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Piotr Gawda, Michał Ginszt, Magdalena Zawadka et al.
Journal of Human Kinetics · 2019
Abstract Patellofemoral pain syndrome (PFPS), the most common source of knee pain among physically active individuals, is defined as anterior knee pain involving the patella and retinaculum that excludes other intraarticular and peri-patellar pathology. Differences in the activation and endurance of the quadriceps components, causing an imbalance in the forces controlling patellar tracking during flexion and extension in the knee joint, appear to be the most commonly reported risk factors for PFPS. The aim of this study was to determine the differences in bioelectric activity of vastus medialis and rectus femoris muscles during half knee bend position in runners with PFPS. The sample comprised 20 recreational runners (15 males, 5 females; aged 27 ± 5 years) reporting knee pain and diagnosed with PFPS. The age- and sex-matched control group consisted of recreational runners who did not report knee pain. The myon electromyographic system was used to determine the changes in the electromyographic median frequency during a half squat position. The decrease in the median frequency of vastus medialis and rectus femoris muscles was significantly greater in runners with PFPS in comparison to the control group (p < 0.01 for right and left vastus medialis and right rectus femoris; p < 0.05 for left rectus femoris). There is a relationship between knee pain related to PFPS and the imbalance of bioelectric activity of vastus medialis and rectus femoris muscles. Achieving the muscular balance within the thigh muscles can be an important factor in the rehabilitation process of PFPS.
Mahtab Roohi-Azizi, L. Azimi, S. Heysieattalab et al.
Medical Journal of the Islamic Republic of Iran · 2017
Background: An electroencephalogram (EEG) is an accepted method in neurophysiology with a wide application. Different types of brain rhythms indicate that simultaneous activity of the brain cortex neurons depend on the person’s mental state. Method: we have focus on reviewing the existing literature pertaining to changes of the brain’s bioelectrical activity that recorded from the scalp in different conditions such as cognition and some mental disorders. Result: The frequency of brain waves may indicate sleep, consciousness, cognition, and some mental disorders. Slow brain waves are seen in some conditions such as sleep, coma, brain death, depression, autism, brain tumors, obsessive–compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), and encephalitis, while rapid waves are generally reported in conditions such as epilepsy, anxiety, posttraumatic stress disorder (PTSD), and drug abuse. Conclusion: Increase in the EEG rhythm is a marker of high brain activity that leads to high degrees of consciousness, while slow waves are suggestive of less brain activity. The pattern of EEG rhythm can be an indicator of some mental disorders, too.
I. V. Zolnikova, S. Milash, A. B. Chernyak et al.
Vestnik oftal'mologii · 2019
PURPOSE To assess the changes in photoreceptor retinal layers and the choroid in comparison with bioelectrical activity of the macula in patients with retinitis pigmentosa (RP). MATERIAL AND METHODS The study included 10 patients (20 phakic eyes) with RP. Mean age was 27±18.5 years; mean best corrected visual acuity was 0.38±0.22. In addition to standard ophthalmological examination and fundus photography, each patient underwent an electrophysiological study on an electroretinograph MBN (Russia) recording general electroretinogram (ERG), maximal ERG (cone-rod response), 30 Hz flicker ERG and macular ERG (mERG). Choroidal thickness (CT) measurement and segmentation of the retina with following calculation of the thickness of different retinal layers was performed on SD-OCT RS-3000 Advance 'Nidek', Japan), it included obtainment of the 6-mm-diameter map in accordance with the Early Treatment Diabetic Retinopathy Study (ETDRS). RESULTS The study revealed a decrease in thickness of the choroid, retina, and the photoreceptor layers: 1) the layer with photoreceptor outer segment (OS) and retinal pigment epithelium (RPE) and 2) the layer with photoreceptor inner segment (IS) and outer nuclear layer. Decreased thickness of these layers is associated with the reduction of bioelectric activity of the macula as seen with mERG. CONCLUSION Decreased thickness of the retina, choroid and photoreceptor layers in all segments of the macula according to EDTRS standards is associated with reduced bioelectric activity of the macula recorded with mERG.
P. Marinescu, Lauren A. Miller, R. Young et al.
Obstetrics & Gynecology · 2019
METHODS: This is an observational cohort study of pregnant women at an urban academic medical center from November 2017 to June 2018. Women with short cervical length (CL) ,2.5 cm were compared to women with normal CL ($3 cm). Primary outcome was pattern of bioelectrical activity in both groups. Secondary outcomes were characteristics of identified signals. All subjects had a singleton pregnancy between 16w0d and 22w6d. Up to 4 proprietary uEMG electrode pads (PreTel, Inc., Chattanooga, TN), 4 commercially available ECG pads, a ground electrode, and a tocometer were placed on the lower abdomen. EMG recordings were obtained for 60 minutes using a Porti amplifier (TMSi, Oldenzaal, Netherlands) and analyzed between 0.15 and 1.2 Hz.
Y. Pigareva, O. Grinchuk, A. Gladkov et al.
Journal of Physics: Conference Series · 2020
Synchronization of neuronal subpopulations and spiking pattern propagation are essential features for bioelectrical activity of the brain. In this study, we proposed an engineering method to grow hierarchically connected networks in vitro through the microchannels and investigated the relations of local spiking propagation through the microchannels with integrated bursting events in the chambers.
Łukasz Oleksy, M. Wojciechowska, A. Mika et al.
Medicine · 2020
Abstract The aim of the study was to evaluate pelvic floor muscle bioelectrical activity in healthy, young, and nulliparous women, and to present normative values for all phases and parameters measured with the Glazer Protocol. In this study, 96 healthy, young, nulliparous women (age 22–27 years; 168.6 ± 5.1 cm; 57.1 ± 11.8 kg) were tested. The bioelectrical activity of the pelvic floor muscles was collected using an endovaginal electrode with the Glazer Protocol, which included the following series of muscles contractions and relaxations: pre-baseline rest, phasic contractions, tonic contractions, isometric contractions for muscle endurance evaluation, and post-baseline rest. The following normative values of the bioelectrical signal for all phases of the Glazer Protocol were calculated: mean, minimal, and maximal values, 95% confidence interval, standard deviation, 95% standard deviation confidence interval, variance, coefficient of variation, and standard error of measurement. Average Mean Amplitude (μV) was as follows: pre-baseline rest (6.26 ± 3.33 μV), phasic contractions (49.76 ± 26.44 μV), tonic contractions (37.05 ± 25.99 μV), endurance contraction (16.10 ± 6.68 μV), and post-baseline rest (6.93 ± 3.99 μV). This study was the first in which normative values for all phases of the Glazer Protocol were reported. This protocol is very often used in electromyography devices as a tool for pelvic floor muscle assessment. Due to the fact that the interpretation of the pelvic floor muscle evaluation is complex and difficult, the authors believe that the normative values proposed in this study allow for comprehensive interpretation of this test (both qualitatively and quantitatively) and provide a reference point for parameters measured in women with different pelvic floor dysfunctions.
Renata Kielnar, A. Mika, D. Bylina et al.
PLOS ONE · 2021
Background Coexistence of temporomandibular joint discomfort along with cervical spine disorders is quite common, and is associated with many limitations and adverse symptoms for the patient. Both diagnostics and treatment of these ailments are difficult, and in many cases, the effects of therapy are not satisfactory. This study assessed the impact of a 3-week neck-only rehabilitation programme without direct intervention in the craniofacial area on the bioelectric activity of both the cervical spine and muscles in the craniofacial area among patients with idiopathic neck pain who do not report TMJ pain. Design A parallel group trial with follow-up; Setting: Rehabilitation Clinic. Methods Twenty five patients experiencing idiopathic neck pain underwent the 3-week rehabilitation programme. Thirty five age-matched subjects with no cervical spine and temporomandibular joint (TMJ) dysfunctions were control group. At baseline and after 3 weeks the cervical and craniofacial area muscles’ bioelectrical activity (sEMG) was evaluated. Results In the experimental group during cervical flexion, a significant decrease of sEMG amplitude was noted in the right (mean 25.1 μV; 95% CI: 21.5–28.6 vs mean 16.8 μV; 95% CI: 13.8–19.7) and left (mean 25.9 μV; 95% CI: 21.7–30.0 vs mean 17.2 μV; 95% CI: 13.6–20.7) Sternocleidomastoid as well as a significant increase in sEMG amplitude of the right (mean 11.1 μV; 95% CI: 7.9–14.2 vs mean 15.7 μV; 95% CI: 12.1–19.2) and left (mean 15.3 μV; 95% CI: 11.9–18.6 vs mean 20.2 μV; 95% CI: 15.7–24.2) Upper Trapezius muscles. In the experimental group, after therapy right and left Sternocleidomastoid, Temporalis Anterior and Masseter muscles presented lower fatigue levels. Conclusions Three weeks of rehabilitation without any therapeutic intervention in temporomandibular joint significantly decreased the bioelectrical activity of the neck and craniofacial muscles while improving the muscle pattern of coactivation in participants with idiopathic neck pain who do not report temporomandibular joint pain. These observations could be helpful in the physiotherapeutic treatment of neck and craniofacial area dysfunctions. Trial registration ID ISRCTN14511735—retrospectively registered.
Grzegorz Zieliński, Michał Baszczowski, M. Râpă et al.
Pain Research and Management · 2022
Objective The present study aimed to evaluate the correlation of eye length and bioelectric activity of temporalis, masseter, digastric, and sternocleidomastoid muscles in women with myopia compared to healthy women. Methods Based on the exclusion and inclusion criteria, 42 women aged 24 years (±2 years) were eligible for the study. Two equally sized groups with myopic (n = 21) and emmetropic healthy subjects (n = 21) were formed. An electromyographic study of the examined muscles was performed in four conditions: at rest, during maximal voluntary clenching in the intercuspal position, during maximal voluntary clenching on dental cotton rollers, and during maximal mouth opening using BioEMG III (BioResearch Associates, Inc. Milwaukee, WI, USA). The IOL Master 500 (Carl Zeiss Meditec, Jena, Germany) was used to examine the eyeball length. Statistical analysis showed significant positive correlations during mouth opening in both groups with open and closed eyes. Results A greater number of correlations between the analyzed variables was observed in emmetropic women. In almost all cases, the longer axial eye length was associated with an increase in the bioelectrical activity of the analyzed muscles. Significant correlations were most often observed within the masseter and digastric muscles during the maximum mouth opening and at rest. Conclusion There is a relationship between the bioelectrical activity of the masticatory muscles and the axial length of the eyeball on the same side.
Grzegorz Zieliński, Anna Matysik-Woźniak, Michał Baszczowski et al.
Scientific Reports · 2022
The study aimed to analyze the changes within the bioelectrical activity of the cervical spine and masticatory muscles during the change of visual stimulus—open and closed eyes test. After applying the inclusion criteria, 50 subjects were included in the study, with visual impairment ranging from −0.5 to −5.75 Diopters. Four muscle pairs were analyzed: the anterior part of the temporalis muscle (TA), the superficial part of the masseter muscle (MM), the anterior belly of the digastric muscle (DA), and the middle part of the sternocleidomastoid muscle (SCM) belly during rest, teeth clenching, teeth clenching on dental cotton rollers, and active mouth opening. Statistical analysis showed a significant decrease in the bioelectrical activity during teeth clenching of all analyzed muscles during the closed eyes test. Significant decreases of electromyographic values were also observed during resting activity within TA muscles, during teeth clenching with dental cotton rollers within SCM and DA muscles, and during active mouth opening within the right masseter. Changing the visual stimulus from open eyes to closed eyes in people with myopia affects the bioelectrical activity of the masticatory and cervical spine muscles.
Grzegorz Zieliński, M. Wójcicki, M. Râpă et al.
CRANIO® · 2023
ABSTRACT Objective The aim of this study was to analyze the correlation between the refractive error, muscle thickness, and the bioelectrical activity of selected masticatory and neck muscles in subjects with myopia. Methods For bioelectrical activity analysis within the masticatory muscles, an 8-channel BioEMG III electromyograph was used. An M-Turbo ultrasound machine was used to analyze the masticatory and neck muscle thickness. Results Statistical analysis showed significant positive correlations between masseter muscle thickness at rest on the right side. Statistical analysis showed negative correlations between the digastric muscle and Activity Index within masticatory muscles at rest on the left side when the eyes were closed. Conclusions As refractive error increases in myopic subjects, the resting tension on the temporal muscles increases, an increase in masseter muscle thickness is noted, and a decrease in bioelectrical activity on the digastric muscle at rest.
Grzegorz Zieliński, Anna Matysik-Woźniak, Michał Baszczowski et al.
International Journal of Environmental Research and Public Health · 2023
Background: Myopia is one of the most common eye disorders involving abnormal focusing of light rays. The studies recognize the association between the stomatognathic and visual systems. This compound may have a neurological basis associated with disorders such as central sensitization. The main aim of this study was to evaluate the influence of central sensitization on the bioelectrical activity of selected muscles of the masticatory organ in subjects with myopia. Methods: Selected masticatory and cervical spine muscles were analyzed using an eight-channel BioEMG III electromyograph. Central sensitization was analyzed using the central sensitization inventory. Results: Statistical analysis revealed significantly higher scores on the central sensitization inventory in subjects with axial myopia compared to subjects without refractive error. Repeated positive correlations were observed in the sternocleidomastoid muscle activity and negative correlations in the digastric muscle activity during open and closed eyes in myopic subjects. Conclusions: Subjects with myopia have an increased score in the central sensitization inventory. The increase in the central sensitization inventory score is connected with the changes within the electromyographic activity of the masticatory and neck muscles. The effect of central sensitization on masticatory muscle activity in myopic subjects requires further study.
K. Tsay, Sara Safari, Abdullah Abu-Samra et al.
Visual Neuroscience · 2023
Abstract To compare the baseline signal between two conditions used to generate the photopic negative response (PhNR) of the full-field electroretinogram (ERG): red flash on a blue background (RoB) and white flash on a white background (LA3). The secondary purpose is to identify how the level of pre-stimulus signal affects obtaining an unambiguous PhNR component. A retrospective chart review was conducted on four cohorts of patients undergoing routine ERG testing. In each group, LA3 was recorded the same way while RoB was generated differently using various luminances of red and blue light. The background bioelectrical activity 30 ms before the flash was extracted, and the root mean square (RMS) of the signal was calculated and compared between RoB and LA3 using Wilcoxon test. Pre-stimulus noise was significantly higher under RoB stimulation versus LA3 in all four conditions for both right and left eyes (ratio RoB/LA3 RMS 1.70 and 1.57 respectively, p < 0.033). There was also no significant difference between the RMS of either LA3 or RoB across protocols, indicating that the baseline noise across cohorts were comparable. Additionally, pre-stimulus noise was higher in signals where PhNR was not clearly identifiable as an ERG component versus signals with the presence of unambiguous PhNR component under RoB in all four groups for both eyes (p < 0.05), whereas the difference under LA3 was less pronounced. Our study suggests that LA3 produces less background bioelectrical activity, likely due to decreased facial muscle activity. As it seems that the pre-stimulus signal level affects PhNR recordability, LA3 may also produce a better-quality signal compared to RoB. Therefore, until conditions for a comparable bioelectrical activity under RoB are established, we believe that LA3 should be considered at least as a supplementary method to evaluate retinal ganglion cell function by ERG.
Olena Popazova, Igor Belenichev, Andrii Abramov et al.
Innovative Biosystems and Bioengineering · 2023
Background. Posthypoxic cardiopathy is one of the risk factors for the development of cardiovascular pathology (rhythm disturbances, vascular dystonia, etc.) in subsequent age periods and requires the development of treatment approaches. Objective. to evaluate the cardioprotective effect of modulators of the NO system by the effect on the ECG of rats after intrauterine hypoxia. Methods. Modeling of prenatal hypoxia (PH) by daily intraperitoneal administration of sodium nitrite solution to pregnant female white rats weighing 220–240 g, aged 4.5 months, from the 16th to the 21st day of pregnancy at a dose of 50 mg/kg. The offspring were administered daily from the 1st to the 30th day of life – tiazotic acid (morpholinium 3-methyl-1,2,4-triazolyl-5-thioacetic acid), 50 mg/kg, angiolin ([S]-2,6-diaminohexane acid 3-methyl-1,2,4-triazolyl-5-thioacecate), 50 mg/kg, L-arginine, 200 mg/kg, meldonium (2-(2-carboxyethyl)-1,1,1-trimethylhydrazinium), 100 mg/kg. Аnd then after 2 months of life, an ECG was recorded using the ECG TUNNEL system (without anesthesia). Results. Postponed PG leads to a decrease in heart rate and significant dominance of parasympathetic innervation in regulation of electrical activity of the heart, which can be caused by sinus blockade and may be a reflection of parasympathetic regulation of the heart instead of sympathetic control of electrical activity in the norm. The effectiveness of drugs can be presented in descending order: angiolin > tiazotic acid > meldonium. Angiolin proved to be more effective than tiazotic acidin normalizing the electrical activity of the heart and restoring the neurogenic regulation of the automatism of the function of the sinus node. Сonclusions. The prospects of further study of modulators of the NO system with different mechanisms of action as means of cardioprotection of posthypoxic disorders of the cardiovascular system in newborns are experimentally substantiated.
Olena Severynovska, Viktoriia Babicheva, Alexey Galinskiiy et al.
International Letters of Natural Sciences · 2015
Evaluation of biopotentials in the region of the amygdala of rats in the combined influence of alcohol and drugs, causing an imbalance of nitric oxide is described in this paper. Chronic alcoholism leads to structural morphological changes in the liver. A study of the amplitude of electrical activity showed that the electrical potential in the amygdala after 8 weeks chronic alcoholism was lower compared with normal rats. The frequency spectrum analysis showed decreased in the 2 times or more absolute spectral powers of all components. The relative spectral powers of its components: δ: θ: α: β was as a 2: 2: 2: 4. The use of sodium nitroprusside (donator of NO) together with the chronic consumption of ethanol reduces the effect of ethanol on low and high-frequence portion the performance of the bioelectrical activities spectrum in the amygdala. The use of non-selective blocker of NO-synthase – nitroarginine aggravated by the braking action of alcohol. The important role of nitric oxide in the development of adaptive-compensatory reactions of the damaged body is described. Our results may be useful to assess the contribution of NO in operation amygdala, conditions of chronic pathologies, and treatment of neuropsychiatric conditions, including diseases caused by alcohol abuse.
Anna Mika, Piotr Mika, Łukasz Oleksy et al.
Journal of Clinical Medicine · 2022
Aim: Intermittent claudication is the most common symptomatic manifestation of peripheral arterial disease (PAD), presenting as ischemic leg muscle pain and gait dysfunction. The aim of this study was to evaluate the changes in bioelectrical activity of the lower limb muscles activity in claudicating patients over a 12-week period of supervised treadmill training and to verify the hypothesis as to which muscles of lower limbs are activated by training treatment—the proximal, as compensatory mechanism, or the distal, which are the most ischemic. Methods: The study comprised 45 patients aged 60–70 years (height 168.8 ± 6.8 cm, weight 78.9 ± 9.2 kg) with PAD and unilateral intermittent claudication (Fontaine stage IIa/IIb), who participated in a 12-week supervised treadmill training program. Surface electromyography (sEMG) of the gastrocnemius lateralis (GaL), gastrocnemius medialis (GaM), tibialis anterior (TA), biceps femoris (BF), rectus femoris (RF) and gluteus medius (GM) muscles in the claudicated leg were continuously measured during the treadmill test. The average mean amplitude and mean amplitude range of the sEMG signal were analyzed. Results: During the treadmill test, after 12 weeks of training, the average mean amplitude of the GM (105 ± 43 vs. 74 ± 38%, p = 0.000008, ES = 0.76), BF (41 ± 22 vs. 33 ± 12%, p = 0.006, ES = 0.45) and GaM (134 ± 50 vs. 114 ± 30%, p = 0.007, ES = 0.48) muscles was significantly lower compared with baseline. The mean amplitude range was significantly decreased after 12 weeks of training in the GM (229 ± 64 vs. 181 ± 62%, p = 0.008, ES = 0.77) and BF (110 ± 69 vs. 84 ± 31%, p = 0.0002, ES = 0.48) muscles. After 12 weeks of training, the mean amplitude range of the TA muscle was significantly higher compared with baseline (104 ± 46 vs. 131 ± 53%, p = 0.001, ES = 0.54), but without significant changes in the average mean amplitude value. The most favorable changes, suggesting the lowest muscle fatigue and the highest walking capacity, were found in patients with the longest walking time. Conclusions: The obtained results may suggest that after 12 weeks of treadmill training, beneficial changes occurred in both the proximal and distal muscles. Therefore, greater foot plantar flexion and stronger push-off as well as greater hip extension may be considered the main mechanisms of observed gait pattern improvement. It may also be suggested that the therapy of gait alterations in patients with PAD should be focused not only on calf muscle pump improvement, but also on proximal hip extensor strengthening.
Oleksandr Kozolkіn, Anton Kuznietsov
Ukrains'kyi Visnyk Psykhonevrolohii · 2020
Aim of the study — to detect electroencephalographic criteria of unfavorable vital outcome of spontaneous supratentorial intracerebral hemorrhage (SSICH). Prospective cohort study of 156 patients (mean age 66,7 ± 0.8 years) in acute period of SSICH on the ground of conservative treatment. Diagnosis was made based on clinical neurological and visualization data. Bioelectrical brain activity was done during first 2 days of the onset. Logistic regressive analysis was used for elaboration of prognostic criteria. It was detected, that risk of lethal SSICH outcome is independently associated with the next spectral EEG‑pattern parameters: relative spectral rhythm of δ-band of intact hemisphere (odds ratio (OR) (95 % confidence interval (CI) is equal to 1.12 (1.08—1.17), p < 0.0001), frontal occipital rhythm gradient of α-band of intact hemisphere (ОR (95 % CI) = 5,96 (1.08—33.04), p = 0.0410) and interhemispheric asymmetry of absolute spectral rhythm power of β2-band (OR (95 % CI) = 0.03 (0.001—0.88), p = 0.0419). These predictors were integrated into the mathematic model for individual prognosis of SSICH lethal outcome (AUC (95 % CI) = 0.95 (0.90—0.98), p < 0.0001, predictive accuracy is equal to 89.7 %). Bilateral predominance of electroencephalographic pattern of δ-band rhythm, inversion of negative frontal occipital rhythm gradients of α-band in both hemispheres, formation of negative interhemispheric asymmetry of absolute spectral rhythm power of δ-band, α2-band in frontal region and θ-, β-bands in parietal occipital regions in first 2 days from the SSICH onset are the EEG criteria for unfavorable vital outcome of SSICH.
Vera I. Potievskaya, F. M. Shvetskiy, M. B. Potievskiy
Annals of Critical Care · 2019
Xenon is an inert gas used like inhalational anesthetic during different surgeries, including high-risk operations and for pain treatment caused by different factors. If concentration of the gas is less than 50 %, or the duration of the procedure is very short, no consciousness depression occurs. 20 healthy persons from 22 to 30 years old were undergone xenon/oxygen inhalation with concentration 70/30 % respectively for 3 minutes. Electroencephalography (EEG) was recorded before, during and 30 minutes later the procedure. For the data processing spectral analysis was used. Statistical analysis was performed by Wilcoxon and Page tests. As a result, significant increase in slow wave activity and reduction in alpha-rhythm activity were observed during and after the procedure as well as repartition of activity zones in brain similar to physiological sleep. This fact may be used in conduction of treatment and diagnostics procedures.
Materials International · 2022
The present work evaluated the inactivation efficiency of atmospheric pressure cold plasma (APCP) against three pathogenic microorganisms. We have successfully developed a plasma device that can generate atmospheric pressure cold argon plasma of low temperature (240 - 270C) downstream using a high-voltage power source (6 kV) operating at a frequency of 19.56 kHz, which can be widely used in biomedicine. Therefore, a cost-effective system of generating cold plasma jets at atmospheric pressure with potential applications in biomedical research has been developed. The discharge has been characterized by an optical method. This research aims to investigate the antimicrobial property shown by the atmospheric pressure cold plasma Jet (APCPJ). Three pathogenic bacterial strains (Shigella flexneri, Escherichia coli, and Klebsiella pneumoniae) were used to test the antimicrobial property. The effects of atmospheric pressure cold plasma (APCP) today have been identified worldwide in disinfection, decontamination, and sterilization, as well as oncology applications. This work aims to demonstrate the effect of APCP irradiated media as a promising anticancer tool. Atmospheric pressure cold plasma technology has the efficacy to show anticancer properties with the treatment of cancer cells. To demonstrate the anticancer properties of APCP generated at a high voltage power supply (12 kV) at an operating frequency of 50 Hz. 10% Dulbecco’s Modified Eagle Medium (DMEM) media were treated with cold plasma using argon as a process gas for various time durations (0.5-4 min). The treated media was transferred to Henrietta Lacks (HeLa) and Human Embryonic Kidneys 293(HEK 293) cells, and the viability of cancer cells was observed using MTT assay.
R. R. Dils
CORROSION 1975 · 1975
The national energy program has focused attention on the desirability of converting plentiful resources of low-grade fossil fuels for power generation. Both in the process of fuel conversion and in the combustion of the converted fuel, the structural components of the manufacturing plant and the power generating equipment using the converted fuel will be subjected to severe attack by oxidation and corrosion. In many of the environments, materials surfaces will be exposed to temperatures, pressures, velocities, or compositions which vary significantly and rapidly with time. The oxidation and hot corrosion of the materials can exhibit a pronounced dependence on the local fluid dynamics in an industrial environment. Surface temperature fluctuations induced either from the unmixedness of the fluid streams or by dynamic variations of the fluid boundary layers are a source of cracking or spallation of protective oxide layers. In addition, the fluid dynamics can cause the deposition of non-equilibrium corrosive agents over a range of conditions far in excess of those expected from equilibrium considerations.
J. P. Engle
CORROSION 1975 · 1975
Carbon steel and many different alloys are exposed to varied environments in equipment designed for power generation. The combustion of fuel may give rise to the formation and release of corrosive compounds in the flue gases. Several examples of corrosion from this source are discussed under the heading of Fireside Corrosion Problems.
Furong Zhu
Research Square · 2024
Abstract The photovoltaic performance and artistic perspectives of the translucent color organic solar cells (OSCs), made with the emerging narrowband nonfullerene organic semiconductors are explored. This work reports the effort to develop high-performance translucent color OSCs comprising a Fabry-Pérot microcavity optical coupling layer, with a power conversion efficiency of >15% and a maximum transparency of >20% for the three primary colors. The performance color relationship of the translucent color OSCs was analyzed using a combination of high-throughput optical computing and experimental optimization, allowing light with desired color to pass through, and yet absorbing enough light to generate electricity. A 10×10 cm2-sized replication of Piet Mondrian's artwork "Composition C (1920)" was demonstrated using the translucent OSCs with a wider palette of colors and a high accuracy of hues. The outcome of the work offers an opportunity for translucent color OSCs to serve as both esthetic art and power generating windowpanes for use in our homes, offices, and even greenhouses.
Salahuddeen M. Tahir, Ali M. Sheriff
SPE Nigeria Annual International Conference and Exhibition · 2019
Abstract About 83% of energy used to generate power in Nigeria is currently derived from gas. This is understandable since the country has huge volumes of gas resources which it intends to take advantage of to grow its economy. Nigeria's gas reserves stands at 199 Tcf as at 01/01/2018 (Department of Petroleum Resources Annual Reserves and Production Report). Gas is the preferred source of energy because of the following; Efficiency in energy generationRelatively low per capita costMeans of eliminating gas flaresIncome generation earner for stakeholderOpportunity for additional job creation Several gas development projects have been embarked upon within the Nigerian Oil and Gas industry to deliver gas to the domestic sector. The Nigerian domestic gas sector is classified into the following three (3) sectors as contained in the Nigerian Gas Master Plan (NGMP); Power – Independent Power Plants (IPPs) e.t.cCommercial – Industries utilizing gas as fuel e.g. Cement PlantsGas Based Industry – Industries utilizing gas as feedstock e.g. Fertilizer Plants Presently, twenty five (25) gas fired plants with a combined installed capacity of about 11,500 MW exist in country. The total gas requirement to run all the plants at full capacity is approximately 3.0Bscfd. Between 2018 and 2037, it is expected that fifty five (55) additional thermal plants will come on stream (Transmission Company of Nigeria Transmission Masterplan). These plants will generate an additional combined power of 19,000 MW and will require gas volumes of approximately 5Bscf/d to generate the power equivalent. As the country's gas reserves are growing, gas production has increased over the years. A current total gas volume of about 8Bscfd is being produced in Nigeria out of which 45% is exported (NLNG), 8.5% is flared, 15% is consumed domestically (Power & Industries) while the balance is either re-injected for pressure maintenance or utilized for operational purposes. The gas to power value chain has been bedeviled by issues which have affected the full generation of power based on installed capacity of existing gas fired power plants. Major among the issues are; Lack of sufficient power transmission capacity from the power generating plantsOff Spec gas volumes supplied to power generating plantsLegacy Debt repayment and payment for gas supplyInadequate gas transportation infrastructureWeak payment structure within the power value chainFunding constraints for development of upstream gas supply sourcesDiffering priorities between upstream gas developersAbsence or ineffective contractual terms between stakeholder parties Steps are being taken to address these issues. Alongside the development of Power Plants, Gas Transportation and Power Transmission Infrastructure are also being developed according to laid down Master Plans. To achieve the ultimate objective of power generation to meet the country's domestic needs, there is a need for alignment on existing master plans within the gas and power sector. This paper attempts to evaluate the Country's gas development plans, the Nigerian Gas Master Plan and the Transmission Master Plan in relation to each other. Gaps (if any) will be identified and solutions proffered to ensure that the Federal Government's objectives are realized.
Wayne Allen, David Anderson, Bert Mayer
2003 International Joint Power Generation Conference · 2003
The Ontario Power Generation (OPG) Pickering B Facility consists of four 540 MW nuclear generating units. Each unit is furnished with a once-through Condenser Cooling Water (CCW) System that uses Lake Ontario water. Zebra mussels (Dreissena polymorpha) are infesting the condenser cooling water intakes at Pickering. The mature mussels and their shells become entrained in the CCW, are deposited in the condenser inlet water boxes, and become lodged in the condenser tube sheets and within the tubes. As a result, the flow through the condenser is reduced, and the existing Condenser Tube Cleaning System (CTCS) performance is degraded. This reduces the Turbine-Generator generating capability that results in a loss of electric generation revenues for OPG, and increased maintenance costs to manually remove the zebra mussels from the condenser. OPG decided to install Debris Filters in the six 72-inch diameter inlets of each of the four Pickering B units to automatically remove the zebra mussels before they enter the condensers and discharge them back into the lake. The Debris Filters for Unit 8 were installed during a scheduled outage in the winter of 2001/2002. The Unit 5 installation was completed at the end of 2002 and the Unit 6 & 7 installations are scheduled for 2003. The installed equipment is performing as expected. The zebra mussels are intercepted by the Debris Filter, and are automatically discharged into the condenser bypass and returned to the lake. The CTCS system can again perform its intended function to prevent bio-fouling buildup inside the condenser tubes. As a result, generation capacity increased and maintenance expenditures decreased with a net result of increased revenues for OPG.
, Thomas Adriaan de Bruin
· 2024
INTRODUCTION In the future, more and more people will live in cities, while the space for renewable energy in urban areas is scarce. As a result, there is a strong need for renewable energy generation technologies that double as a building element to sustainably supply our future cities. A promising technology is the luminescent solar concentrator (LSC), which is a type of transparent solar panel. The LSC can function as a window while at the same time generating renewable electricity. The LSC uses luminescent particles to absorb and emit sunlight, which is guided through the window glass to solar cells attached at the sides. This leads to a trade-off between the transmitted light necessary for functioning as a window and the absorbed light necessary to generate electricity. RESEARCH QUESTIONS The main question research question is: "Is it possible to develop efficient, transparent, and durable luminescent solar concentrators to replace conventional windows?" For LSCs to function as a window, they need to be sufficiently transparent while being efficient enough to generate a significant amount of electricity. Furthermore, they need to be able to maintain this power output for a long period of time in an outdoor environment. In this thesis, these requirements are investigated in six chapters that broadly cover the following three topics. Chapter 2 and 3: The viability of tandem configurations is explored, i.e., the stacking of two different LSCs, and the maximum theoretical efficiency of LSCs is researched. Chapter 4 and 5: A novel algorithm that is much quicker than previous algorithms is introduced. The algorithm calculates the maximum efficiency based on existing LSC data from the scientific literature. Chapter 6 and 7: The performance of LSCs during and after two years in an outdoor environment is presented. The results from chapters two to seven provide the answer to the main research question. RESULTS The results based on the six chapters: Chapters 2 and 3: Tandem configurations are feasible but do not lead to significantly better performances for the tested luminophores. The maximum theoretical power conversion efficiency for a luminescent solar concentrator that functions as a window is around 10%. Chapters 4 and 5: The maximum power conversion efficiency for window-appropriate LSCs based on currently existing luminophores is around 1%. Chapters 6 and 7: LSCs in an outdoor environment perform well over a full day, showing consistent performance for sunny and cloudy days and can remain stable after two years. CONCLUSION AND DISCUSSION Based on chapters two and three and chapters six and seven, the LSC can theoretically have an efficiency of 10%, and it can remain stable for more than two years in an outdoor environment. However, based on chapters four and five, the currently feasible efficiency for an LSC that can function as a window is around 1%. As a result, the answer to the research question is that durable and transparent LSCs are feasible but with a maximum efficiency of 1%. Future research should focus on improved LSCs and alternative applications, e.g., in agriculture.
Elis Nycander, Lennart Söder
· 2021
<pre>Efficient integration of variable renewable energy (VRE) such as wind power into power systems requires methods for power system operation planning that account for VRE uncertainty and variability. This has motivated extensive research into unit commitment (UC) and optimal power flow (OPF) formulations with VRE uncertainty. However, these formulations are often tested using significantly simplified representations of VRE production. We seek to address this issue by providing a model for generating realistic wind power scenarios using real production and forecast data. The scenarios are generated using 5-min production and 30-min forecast data for real wind farms from Australia. The model captures the empirical distribution of the forecast errors and the covariance between different wind farms. The high time resolution of the production data also allows the recreation of the high-frequency (5-min) component of wind power production. The resulting model is openly available, and can be used to generate wind power scenarios for use in formulations for operation planning of power systems (UC/OPF) considering wind uncertainty and intra-hour variability. The scenarios can be tailored according to preferences for, e.g., the number of wind farms and their geographical dispersion.</pre>
Lama Fayad, Rania Amer, Ali Hammoud et al.
BAU Journal - Science and Technology · 2022
Global warming and the accumulation of organic waste constitute a serious environmental problem. Therefore, microbial fuel cells (MFC) are an eco-friendly device that have significant capability for the production of electricity using biodegradable waste as fuel. Microorganisms used as catalysts in the anode compartment, execute a principal function in operating MFCs. The present study was conducted to isolate and to screen potential bioelectricity generating microorganisms from dumpsite soil samples and also to construct a domestic dual-chambered microbial fuel cell (MFC). Streptomyces fimicarius was found to be the best isolate for the degradation of cellulose and the production of bioelectricity. The bacterial isolate was identified based on morphological characteristics, biochemical characteristics and molecular identification using 16S rRNA. Double-chambered MFC was constructed by using two polypropylene plastic containers of 1.4 L volume each. The two chambers were joined by using an agar salt bridge and carbon rods were utilized as electrodes. The generation of electricity by the isolate was compared using glucose and cellulose as sole carbon source in a minimal medium. The maximum voltage was found to be 322 mV in the presence of cellulose used as substrate after 5 days of incubation at room temperature and last for 10 days.
Maarten Goedseels, Chris W. Michiels
Microorganisms · 2023
Hop beta acids (HBAs) are characteristic compounds from the hop plant that are of interest for their strong antimicrobial activity. In this work, we report a resistance mechanism against HBA in the foodborne pathogen Listeria monocytogenes. Using an evolution experiment, we isolated two HBA-resistant mutants with mutations in the mprF gene, which codes for the Multiple Peptide Resistance Factor, an enzyme that confers resistance to cationic peptides and antibiotics in several Gram-positive bacteria by lysinylating membrane phospholipids. Besides the deletion of mprF, the deletion of dltA, which mediates the alanylation of teichoic acids, resulted in increased HBA resistance, suggesting that resistance may be caused by a reduction in positive charges on the cell surface. Additionally, we found that this resistance is maintained at low pH, indicating that the resistance mechanism is not solely based on electrostatic interactions of HBA with the cell surface. Finally, we showed that the HBA-resistant mutants display collateral sensitivity to the cationic antimicrobials polymyxin B and nisin, which may open perspectives for combining antimicrobials to prevent resistance development.
D.D. Stephen
Offshore Technology Conference · 1975
Introduction The commissioning of an electrical installation off-shore on a drilling/ production platform presents very different problems to those experienced with equivalent equipment on-shore. Many factors combine to cause this and among the most important are the restricted number of personnel which can be accommodated, the significance of time delay on a project with such high capital investment, the great importance placed on the maximum safety, security, and reliability throughout the complete operation, the concentration and complexity of the many control, monitoring, safety and alarm systems in combination with the many systems of power generation provided, and not least the adverse environmental conditions suffered by the equipment during erection, storage and transportation in modules, and final erection on the platform with considerable exposure to shock, vibration and severe climatic conditions. To reduce these off-shore problems and ensure minimum off-shore time required to put the electrical system to work it was decided to carry out full-scale on-shore testing programmes on the electrical generation equipment for the first two BP Forties platforms. These involved considerable logistical problems as well as those involved in the purely technical operations but the results obtained from both sets of tests have fully justified the operation. Testing Programme The electrical generation equipment and its layout on the platform has been fully described elsewhere, refs. 1, 2 and 3. Packages 1 and VII contain the main gasturbine generator sets, their control and starting equipment, the 11 kV switchgear, power transformers, 3.3 kV switchgear convert or equipment, diesel-generator ' set,415V switchgear and motor control centres, and items such as switchgear batteries, neutral earthing resistors and items necessary to provide a complete generation system. By placing these two packages close to each other, in the case of the Rotterdam unit on the same barge, interconnection was relatively simple. Although all the separate items of equipment were fully inspected and tested at their place of manufacture many of the control and operation sequences are unique and had not been used previously on such a concentrated and self-contained system. In addition the procedures of packing, transportation, prolonged storage, sometimes under adverse environmental conditions, erection in modules still under fabrication, and intercabling, all combine to introduce a high probability that considerable rechecking would be essential to detect any damage or deficiencies. It was also considered desirable to fully test and prove the coordinated functioning of interconnected systems of power generation, control, protection and instrumentation whose components had never been operated conjointly although this would require considerable expenditure on test equipment and manpower. The testing programme enabled the following aspects to be proved to a very high degree ofcompletion.
Komandur Sunder Raj
ASME 2019 Power Conference · 2019
Abstract Significant research is ongoing on several fronts in smart sensor technologies for optimizing the performance of power generating assets. The initiatives include: 1. Real-time models with advanced computational algorithms, embedded intelligence at sensor and component level for reducing operating costs, improving efficiencies, and lowering emissions. 2. Optical sapphire sensors for monitoring operation and performance of critical components in harsh environments, for improving accuracy of measurements in combustion monitoring, and lowering operating costs. 3. Wireless technologies using (a) microwave acoustic sensors for real-time monitoring of equipment in high temperature/pressure environments (b) integrated gas/temperature acoustic sensors for combustion monitoring in diverse harsh environment locations to improve combustion efficiency, reduce emissions, and lower maintenance costs (c) sensors for sensing temperature, strain and soot accumulation inside coal-fired boilers for detailed condition monitoring, better understanding of combustion and heat exchange processes, improved designs, more efficient operation. 4. Distributed optical fiber sensing system for real-time monitoring and optimization of high temperature profiles for improving efficiency and lowering emissions. 5. Smart parts with embedded sensors for in situ monitoring of multiple parameters in existing and new facilities. 6. Optimizing advanced 3D manufacturing processes for embedded sensors in components for harsh environments to reduce costs and improve efficiency of power generation facilities with carbon capture capabilities. 7. New energy-harvesting materials for powering wireless sensors in harsh environments, improving reliability of wireless sensors in demanding environments, and in-situ monitoring and performance of devices and systems. 8. Real-time, accurate and reliable monitoring of temperature at distributed locations of sensors in harsh environments for improving operations and reducing operating costs. 9. Algorithms and methodologies for designing control systems utilizing distributed intelligence for optimal control of power generation facilities. 10. Gas sensors for monitoring high temperatures in harsh environments for lowering operating costs and better control of operations. 11. Optimizing placement of smart sensors in networks for cognitive behavior and self-learning. This paper provides an overview of the initiatives in smart sensor technologies and their applications in optimizing the performance of power generating facilities.
· 2010
A generating station is an industrial facility built and operated to generate electricity. The map shows the 916 generating stations (power plants) operating in 2007. There were 479 hydroelectric stations, 375 thermal plants (combustion, internal combustion and steam), 7 nuclear plants, 54 wind turbines and 1 tidal power plant.
Chao-Nan Wang, Yoko Masuda, Keishi Senoo
Microorganisms · 2025
Rice paddy fields are sustainable agricultural systems as soil microorganisms help maintain nitrogen fertility through generating ammonium. In these soils, dissimilatory nitrate reduction to ammonium (DNRA), nitrogen fixation, and denitrification are closely linked. DNRA and denitrification share the same initial steps and nitrogen gas, the end product of denitrification, can serve as a substrate for nitrogen fixation. However, the microorganisms responsible for these three reductive nitrogen transformations, particularly those focused on ammonium generation, have not been comprehensively characterized. In this study, we used stable isotope probing with 15NO3−, 15N2O, and 15N2, combined with 16S rRNA high-throughput sequencing and metatranscriptomics, to identify ammonium-generating microbial consortia in paddy soils. Our results revealed that several bacterial families actively contribute to ammonium generation under different nitrogen substrate conditions. Specifically, Geobacteraceae (N2O and +N2), Bacillaceae (+NO3− and +N2), Rhodocyclaceae (+N2O and +N2), Anaeromyxobacteraceae (+NO3− and +N2O), and Clostridiaceae (+NO3− and +N2) were involved. Many of these bacteria participate in key ecological processes typical of paddy environments, including iron or sulfate reduction and rice straw decomposition. This study revealed the ammonium-generating microbial consortia in paddy soil that contain several key bacterial drivers of multiple reductive nitrogen transformations and suggested their diverse functions in paddy soil metabolism.
Patric M Vaelli, K. Theis, Janet E. Williams et al.
eLife · 2020
Rough-skinned newts (Taricha granulosa) use tetrodotoxin (TTX) to block voltage-gated sodium (Nav) channels as a chemical defense against predation. Interestingly, newts exhibit extreme population-level variation in toxicity attributed to a coevolutionary arms race with TTX-resistant predatory snakes, but the source of TTX in newts is unknown. Here, we investigated whether symbiotic bacteria isolated from toxic newts could produce TTX. We characterized the skin-associated microbiota from a toxic and non-toxic population of newts and established pure cultures of isolated bacterial symbionts from toxic newts. We then screened bacterial culture media for TTX using LC-MS/MS and identified TTX-producing bacterial strains from four genera, including Aeromonas, Pseudomonas, Shewanella, and Sphingopyxis. Additionally, we sequenced the Nav channel gene family in toxic newts and found that newts expressed Nav channels with modified TTX binding sites, conferring extreme physiological resistance to TTX. This study highlights the complex interactions among adaptive physiology, animal-bacterial symbiosis, and ecological context.
E.D. Kuzina, I. P. Ivanova, I. Piskarev
Science Intensive Technologies · 2024
The work is devoted to the use of an electric discharge in the geometry of a point electrode – a plane surface for the sterilization of water and surfaces contaminated with bacteria. The relationship between the concentrations of oxidizing impurities and active species generated in an electric discharge is discussed. It is shown that if the concentration of active species is too high, they will interact predominantly with each other and die without producing any effect. Using the example of cyanide decomposition, it is shown that the highest decomposition efficiency is achieved at the maximum voltage on the discharge electrode and the minimum electric discharge current. Therefore, a corona electric discharge was chosen for work. In a corona electric discharge generator in air in the presence of water vapor, an ozone-hydroxyl mixture is formed, in which the lifetime of hydroxyl radicals is ~ 1 sec. This makes it possible to extract hydroxyl radicals from the discharge cavity and ensure their contact with the water flow. After treatment in the generator, the water is purified from impurities within the limits allowed by the release of active species concentration, saturated with ozone and air oxygen to the solubility limit at a given water temperature, and becomes oxygenated. For the experiments, a prototype of the corona electric discharge generator was made. The voltage applied to the discharge electrodes was minus 11 kV, and the total discharge current was 1.7 mA. The choice of parameters of the electrical circuit that forms and maintains the corona discharge is analyzed. The bactericidal effect of the generator was determined for a liquid contaminated with bacteria and for a contaminated surface. The bactericidal effect of the liquid was evaluated after passing it through the reactor of the corona discharge generator. Water flow 150 L/h. The energy costs for reducing CFU (Coli Forming Units) by 10 times for an aqueous solution containing the bacteria Escherichia coli, Enterobacter cloacae, Pseudomonas aeruginosa, Enterococcus faecalis at a concentration of 10–103 CFU per 100 ml of solution are 59±6 J/100 ml of solution for each type of bacteria. Surface sterilization was carried out by spraying the contaminated surface with water after its treatment in the generator reactor. The area of contaminated samples was 25 cm2. To reduce CFU by 10 times on a surface contaminated with gram-negative bacteria Escherichia coli and gram-positive bacteria Staphylococcus aureus at a concentration of 104 CFU/cm2, an energy of 100±11 J/cm2 was expended. High energy costs for surface sterilization are associated with the inefficient use of oxygenated water in this experiment, since the water was drained from the surface without losing its activity. Water retains noticeable activity up to 4 hours. Thus, the water produced by the generator can disinfect large surfaces, which will significantly reduce energy costs. For comparison, the solution was disinfected with UV radiation by irradiation in a Petri dish. A DKB-9 low-pressure mercury lamp emitting 253.7 nm photons was used. The energy spent on reducing CFU by 10 times was 1.6±0.2 and 0.7±0.1 J/cm2 for Staphylococcus aureus and Escherichia coli, respectively. The advantage of decontamination with oxygenated water is that contaminated objects can be washed from all sides, which is not possible using lamp radiation. The results obtained make it possible to calculate the modes of sterilization of a liquid and a contaminated surface using a corona discharge generator and oxygenated water depending on the concentration of microorganisms. Oxygenated water is an environmentally friendly disinfectant, since the active species formed during the generator treatment break down into water and oxygen over time.
Md Fahim Ansari, Fahad Afzal, S. Mehra
Biosciences Biotechnology Research Asia · 2023
ABSTRACT: Ensuring food and water safety has always been a health challenge globally. The present papers underscores HV-PEF (High Voltage Pulsed Electric Field), a novel approach to eliminate five kinds of microbes prevalent in milk and water in fractions of a second. These microorganisms are Enterobaracter aerogenes, Escherichia coli, Listeria monocytogene, Staphylococcus aurous, and Acetobacter. Objective was to find out the impact of HV-PEF on survival of selected species of bacteria, which are often considered as a concern for water and milk safety. A laboratory experimental setup was designed for producing HV-PEF, which was applied on sample of water and milk. The water sample was obtained from tap, and the milk sample was obtained from Bubalus bubalis. The microbial count was measured by plate method for both samples pre and post exposure to the HV-PEF. The effect was measured with combinations of varying field intensity and number of pulses, the intensity of the field having the highest value of 180 kV/cm (kilovolt-per-centimeter), and the pulse count varied between one to one hundred. Results showed, the endurance of few species was extremely low, at 40 kV filed intensity and 40 pulses. Other microbes also demonstrated low survival ratio (SR) at more than 40kV with pulses-count above 40. Complete inactivation of E. coli was achieved at around 80kV. The inactivation of microbe by HV-PEF varies with morphology and shape of the microorganisms. The annihilation of microorganisms is due to the rupturing of cell wall of microbe by the effect of HV-PEF, instead of ohmic heating (resistance induced).
S. Razavi, A. Sarafraz
Medbiotech Journal · 2020
Microbial fuel cells are devices that generate electricity by using the chemical energy which is hidden in the substrates. Bacillus subtilis and Shewanella, connected in series, were used in order to increase the voltage. A bio cathode was used as an oxygen acceptor which was filled by Chlorella vulgaris. An amount of 200 mL molasses was used in the anode, and 200 mL BBM in the cathode. Nafion 115 was used as a PEM at 27˚C under microaerophilic conditions prepared for these experiments. At the same time as producing electricity, the basic protease was generated in the anode chamber containing B.subtilis. This protease was detected by Bradford’s test. The series connection of MFCs increased the voltage, and for the first time, we succeeded in producing biological products like enzymes in MFCs.
S Mahitha, J M Sasi Premila, D Abiya Chelliah
Research Square · 2022
Abstract Plastic pollution need to be resolved as it affects air, water, land. The favourable alternative for plastics would be Polyhydroxybutyrate (PHB) from bacterial origin, which are biodegradable and biocompatible biopolymers. Focus on the PHB producing bacteria is done by collecting garden soil sample. Five colonies of Sudan black blue positive isolates were chosen, extracted, and produced. One of the strains (SM1) - a potent producer as confirmed by crotonic acid assay, was further subjected to large scale production. The PHB thus produced was analysed using Fourier Transform Infra-Red spectroscopy (FTIR) and Gas Chromatography Mass Spectrometry (GCMS) to confirm the presence of functional groups. X-Ray crystallography revealed that it is of crystalline nature and are pictured by Scanning electron microscopy photography. DNA was isolated from the strain SM1, and the gene for 16S rRNA has been sequenced and submitted in GENBANK, (Accession No: MZ363886). The organism was found to be Bacillus cereus as predicted by 16S rRNA and NCBI BLAST. A phylogenetic tree was constructed using MEGA software. Bioplastic preparation was done under laboratory scale and the produced bioplastic was successfully degraded using Pseudomonas species . The prepared bioplastic from bacteria was biodegradable and eco-friendly.
Isma Kurniatanty, Esti Wahyu Widowati
EPiC Series in Biological Sciences · 2021
Protease is an enzyme with high economic value and has been used in industries. Much natural waste can be considered as promising sources protease producing bacteria, such as tofu waste. The objective of the present study was to screen and isolate protease producing bacteria from tofu waste collected from Yogyakarta. Tofu waste samples were serially diluted and 0.1 ml of sample was spread on skim milk agar, at 37oC for 48 hours. Four bacterial colonies showed a clear zone around the colony, indicating protease activity. These isolates (encoded as TWB-1, TWB-2, TWB-3, and TWB-4) were subjected to several biochemical tests and gram staining. Protease activity was determined using the tyrosine standard curve with the casein-Hammarsten substrate. Protease activity of TWB-1, TWB-2, TWB-3, and TWB-4 were 2.85, 5.74, 5.14, and 3.00 respectively. Isolate TWB-2 showed the maximum protease activity with 5.74 U/ml.
Neeksha Naik, Dhanyashree Rai, Shwetha Madival et al.
Research Square · 2023
Abstract Certain microorganisms in nature produce intracellular linear bio-esters called Polyhydroxyalkanoates (PHA), under limited nutrient condition in the presence of excess carbon. PHAs are environment friendly macromolecules exhibit properties similar to petrochemical plastics. In the present study a total of 30 soil samples were collected from different sites and screened for PHA producing bacteria. Among them 30 isolates were showed positive for PHA production by preliminary screening methods. Growing conditions for the synthesis of PHA were optimized. The recovered bacteria were able to produce PHA after 72 hours of incubation at 30°C, pH 7, with 10% inoculum. The positive PHA-producing bacterial strains were identified using 16S rRNA sequencing. The PHA accumulation was up to 59% by PHAD13 isolate, Bacillus subtilis isolated from the petrol bunk soil, NG6 isolate, Klebsiella spp. isolated from garden soil showed 33.5% and the maximum PHA accumulation was about 35.1% by NS1, Bacillus spp. isolated from sewage soil. Intracellular accumulation of PHA for the highest PHA producing isolate PHAD13 was analysed by Transmission electron microscope further characterized using FT-IR. All these diverse sources (Petrol bunk soil, Sewage soil, Garden soil) were shown to be rich sources variety of bacterial species with the ability to produce PHA thereby rendering the biodegradation.
Ciamak Ghazaei
Journal of Clinical Research in Paramedical Sciences · 2022
Background: The emergence of antimicrobial resistance results in morbidities and mortalities associated with many bacterial infections and is a major concerning issue in front of the healthcare system. As a part of a competitive adaptive strategy for its growth, gram-positive bacteria like Bacillus subtilis produce antimicrobial peptides; bacteriocins. These peptides protect other bacterial species. Objectives: To counter antimicrobial resistance, bacteriocins can be considered a potential drug option against drug-resistant microorganisms. Methods: After isolation and characterisation of B. subtilis from the 5 collected soil samples, the bacteriocin was extracted from these bacteria by using the ‘solvent extraction method’, characterised, and then purified to evaluate its antimicrobial activity against pathogenic bacteria like; Streptococcus pyogenes, Salmonella typhi, Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii by using ‘Kirby-Bauer disc diffusion’, method. The bacteriocin stability was also investigated, at different temperatures, pH and incubation times. Results: The bacteriocin of B. subtilis showed great antimicrobial activity against S. pyogenes, followed by S. typhi and P. aeruginosa. However, the lowest antimicrobial activity was against A. baumannii. With the increase in the incubation time and temperature, the antimicrobial activity of bacteriocin was decreased, indicating the protein nature of bacteriocin. Compared to the standard antibiotics, the bacteriocin isolated from B. subtilis demonstrated a significant inhibitory effect against the tested pathogens. Conclusions: From this study, it can be concluded that bacteriocin can become a potential alternative to standard available medicines. They can be used against antimicrobial-resistant pathogenic bacteria because of their significant inhibitory activity against the tested pathogens compared to the standard antibiotics.
, Arora Ragini, Jha Harit
JOURNAL OF CLINICAL AND BIOMEDICAL SCIENCES · 2025
Background: Oxidative stress, caused by an imbalance between reactive oxygen species (ROS) and antioxidant defences, is implicated in numerous degenerative diseases. The search for natural antioxidants has led to the exploration of thermophilic bacteria, known for thriving in extreme environments and potentially producing potent antioxidant compounds. Objective: The purpose of this study was to isolate and characterize thermophilic bacteria collected at Tatapani Hot Spring and evaluate their antioxidant potential. Methods: Water samples were collected from Tatapani Hot Spring and subjected to bacterial isolation using the Spread Plate and Enrichment Culture Method. Isolated strains were characterized morphologically, biochemically, and molecularly via 16S rRNA gene sequencing. Carotenoids and quinones were extracted from the fermentation medium and analyzed for antioxidant activity using UV-Visible spectroscopy. The antioxidant potential of the extracts was assessed through various assays, including DPPH radical scavenging, hydroxyl radical scavenging, nitric oxide radical scavenging, and Ferric ion reducing antioxidant power (FRAP) assays. Results: Two thermophilic bacterial strains, referred to as TR1 and TR2, were successfully isolated. Both strains are Gram-positive, endospore-forming rods. Strain TR1 exhibited 98.70% sequence similarity to Bacillus nakamurai, while strain TR2 showed 99.65% similarity to Bacillus licheniformis. Extracts from these strains revealed significant antioxidant activities, with ethanol extracts demonstrating superior efficacy. Specifically, the ethanol-dissolved extracts exhibited DPPH radical scavenging activity of approximately 80%, hydroxyl radical scavenging activity up to 95.5%, and nitric oxide radical scavenging activity around 87.4%. The FRAP assay confirmed the strong reducing power of the extracts. Conclusion: The thermophiles collected at Tatapani Hot Spring produce potent antioxidant compounds, primarily carotenoids and quinones, with substantial scavenging activities. These findings highlight the potential of these bacteria as sources of natural antioxidants for applications in pharmaceuticals, nutraceuticals, and cosmetics. Future research should focus on optimizing the extraction processes and further characterizing these bioactive compounds to fully exploit their therapeutic potential. Keywords: Thermophilic bacteria; Antioxidant activity; Bacillus species; Bioactive compounds