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Jaewoo Son, J. H. Jang, I. H. Choi et al.
Microbial Cell Factories · 2021
Background trans -cinnamic acid ( t -CA) is a phenylpropanoid with a broad spectrum of biological activities including antioxidant and antibacterial activities, and it also has high potential in food and cosmetic applications. Although significant progress has been made in the production of t -CA using microorganisms, its relatively low product titers still need to be improved. In this study, we engineered Corynebacterium glutamicum as a whole-cell catalyst for the bioconversion of l -phenylalanine ( l -Phe) into t -CA and developed a repeated bioconversion process. Results An expression module based on a phenylalanine ammonia lyase-encoding gene from Streptomyces maritimus (SmPAL), which mediates the conversion of l -Phe into t -CA, was constructed in C. glutamicum . Using the strong promoter P H36 and ribosome binding site (RBS) (in front of gene 10 of the T7 phage), and a high-copy number plasmid, SmPAL could be expressed to levels as high as 39.1% of the total proteins in C. glutamicum . Next, to improve t -CA production at an industrial scale, reaction conditions including temperature and pH were optimized; t -CA production reached up to 6.7 mM/h in a bioreactor under optimal conditions (50 °C and pH 8.5, using NaOH as base solution). Finally, a recycling system was developed by coupling membrane filtration with the bioreactor, and the engineered C. glutamicum successfully produced 13.7 mM of t -CA (24.3 g) from 18.2 mM of l -Phe (36 g) and thus with a yield of 75% (0.75 mol/mol) through repetitive supplementation. Conclusions We developed a highly efficient bioconversion process using C. glutamicum as a biocatalyst and a micromembrane-based cell recycling system. To the best of our knowledge, this is the first report on t -CA production in C. glutamicum , and this robust platform will contribute to the development of an industrially relevant platform for the production of t -CA using microorganisms.
Harish Karthikeyan Ravi, A. Degrou, J. Costil et al.
Processes · 2020
Each year, the food supply chain produces more than 1.3 billion tons of food and agricultural waste, which poses serious environmental problems. The loss of the massive quantity of secondary and primary metabolites retrievable from this resource is a significant concern. What if there is a global solution that caters to the numerous problems arising due to the humongous volume of waste biomass generated in every part of the world? Insects, the tiny creatures that thrive in decaying organic matter, which can concentrate the nutrients present in dilute quantities in a variety of by-products, are an economically viable option. The bioconversion and nutritional upcycling of waste biomass with insects yield high-value products such as protein, lipids, chitin and frass. Insect-derived proteins can replace conventional protein sources in feed formulations. Notably, the ability of the black soldier fly (BSF) or Hermetia illucens to grow on diverse substrates such as agri-food industry side streams and other organic waste proves advantageous. However, the data on industrial-scale extraction, fractionation techniques and biorefinery schemes for screening the nutritional potential of BSF are scarce. This review attempts to break down every facet of insect processing and analyze the processing methods of BSF, and the functional properties of nutrients obtained thereof.
Qihong Lu, Yongyi Liang, Wenwen Fang et al.
Environmental Science & Technology · 2021
Surface sediments of polluted urban rivers can be a reservoir of hydrophobic persistent organic pollutants (POPs). In this study, we comprehensively assessed the contamination of two groups of POPs, that is, polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), in 173 black-odorous urban rivers in China. Spatial distribution of PCBs and PBDEs showed similar patterns but very different contamination levels in surface sediments, that is, average concentrations of 10.73 and 401.16 ng/g dw for the ∑PCBs and ∑PBDEs, respectively. Tetra-/di-CBs and deca-BDE are major PCBs and PBDEs and accounted for 59.11 and 95.11 wt % of the ∑PCBs and ∑PBDEs, respectively. Compared with the persistence of PBDEs, the EF changes of chiral PCBs together with previous cultivation evidence indicated indigenous bioconversion of PCBs in black-odorous urban rivers, particularly the involvement of uncharacterized Dehalococcoidia in PCB dechlorination. Major PCB sources (and their relative contributions) included pigment/painting (25.36%), e-waste (22.92%), metallurgical industry (13.25%), and e-waste/biological degradation process (10.95%). A risk assessment indicated that exposure of resident organisms in urban river sediments to deca-/penta-BDEs could pose a high ecological risk. This study provides the first insight into the contamination, conversion and ecological risk of PCBs and PBDEs in nationwide polluted urban rivers in China.
C. Scieuzo, Antonio Franco, R. Salvia et al.
Insect Science · 2022
Bioconversion is a biological process by which organic materials are converted into products with higher biological and commercial value. During its larval stage the black soldier fly Hermetia illucens is extremely voracious and can feed on a wide variety of organic materials. To study the impact of different fruit byproducts on the insect's growth, final larval biomass, substrate reduction, bioconversion parameters, and larval nutritional composition, 10 000 black soldier fly larvae (BSFL) were reared on 7.0 kg of one of three substrates (strawberry, tangerine, or orange) or on a standard diet as a control. The results highlight that BSFL can successfully feed and grow on each of these diets, though their development time, growth rate, and final biomass were differently impacted by the substrates, with strawberry being the most suitable. The lipid and protein contents of BSFL were similar among larvae fed on different substrates; however, major differences were detected in ash, micronutrient, fiber, fatty acid, and amino acid contents. Overall, the results indicate that fruit waste management through the BSFL bioconversion process represents a commercially promising resource for regional and national agrifood companies. Our study offers new perspectives for sustainable and environmentally friendly industrial development by which fruit byproducts or waste might be disposed of or unconventionally enhanced to create secondary products of high biological and economic value, including BSFL biomass as animal feed or, in perspective, as alternative protein source for human nutrition.
W.W. Clarkson, X. Xiao
Water Science and Technology · 2000
Anaerobic bioconversion of newsprint and waste office paper was performed in bench-scale reactors with three inocula sources: landfill, rumen, and anaerobic digester. Office paper bioconversion was nearly complete within 20 days but continued for about 165 days with methane yield efficiencies ranging from 71–85% of potential chemical oxygen demand (COD) conversion. Average newsprint methane conversion efficiencies ranged from 32–41% of total COD under strictly anaerobic conditions for 300 days. Mass balance calculations revealed that more than 80% of newsprint cellulose was biodegraded. The apparent limiting factor for anaerobic bioconversion of newsprint was the physical association between lignin and cellulose. After proper acclimation, the three inocula tested equally well for methane production under strictly anaerobic conditions. Testing of ground, shredded strips, and whole paper pieces showed no effects of feedstock size on bioconversion rate or extent. Alkali pretreatment with NaOH concentration up to 10% significantly improved newsprint biodegradability. Treatment for longer duration or at elevated temperatures increased the solubilization of lignin, but did not improve bioconversion of newsprint to methane. Neutralizing treated samples with carbon dioxide gave higher methane yields compared to sulfuric or hydrochloric acids, suggesting that digester neutralization could be combined with biogas scrubbing.
Jens Boyen, Patrick Fink, Christoph Mensens et al.
bioRxiv (Cold Spring Harbor Laboratory) · 2019
Abstract By 2100, global warming is predicted to significantly reduce the capacity of marine primary producers for long-chain polyunsaturated fatty acid (LC-PUFA) synthesis. Primary consumers such as harpacticoid copepods (Crustacea) might mitigate the resulting adverse effects on the food web by increased LC-PUFA bioconversion. Here, we present a high-quality de novo transcriptome assembly of the copepod Platychelipus littoralis , exposed to changes in both temperature (+3°C) and dietary LC-PUFA availability. Using this transcriptome, we detected multiple transcripts putatively encoding for LC-PUFA-bioconverting front-end fatty acid desaturases and elongases, and performed phylogenetic analyses to identify their relationship with sequences of other (crustacean) taxa. While temperature affected the absolute fatty acid concentrations in copepods, LC-PUFA levels remained unaltered even when copepods were fed a LC-PUFA-deficient diet. While this suggests plasticity of LC-PUFA bioconversion within P. littoralis , none of the putative front-end desaturase or elongase transcripts were differentially expressed under the applied treatments. Nevertheless, the transcriptome presented here provides a sound basis for future ecophysiological research on harpacticoid copepods.
Ramu Selvam, Paul Olusegun Bankole, PhD et al.
Research Square · 2023
Abstract Vermistabilization of the textile industrial sludge (TS) was carried out on a pilot scale with the help of the earthworm Eudrilus eugeniae . TS was mixed with cow dung (CD) in a ratio of 1:1 and thereafter subjected to vermicomposting for 90 days. Earthworms’ weights increased significantly by 55% in the feed mixture within 45 days of inoculation. Physicochemical parameters significantly reduced during vermicomposting (pH, EC, TDS, TOC, and NH 3 -N) whereas TKN, TP, TK were found to be significantly elevated in the final product. Except for Mn and Zn, the addition of amendments increased earthworm activity, which greatly reduced the content of heavy metals (Al, As, Cd, Cu, Pb, Ni, Cr, Mo, and Hg). Germination index (100%) of Brassica nigra was recorded in the feed mixture. The shoot and root length ranged from 2.26 and 4.36 after 90 days. Genotoxicity analysis revealed a 9.45–10.40% reduction in aberration frequencies of vermistabilized extracts in comparison with control (extracts of TS and CD only). The present study concluded that the deployment of vermistabilized extracts looks promising as a sustainable waste disposal management technology.
Chaichi Devi, Meena Khwairakpam
New Generation of Organic Fertilizers · 2022
Organic fertilizers are alternative to chemicals used in agriculture which enhance soil quality, prevent harmful chemicals entering into food chain, improve health and contribute to sustainable future socially, economically and ecologically. Vermicompost is a nutrient-rich organic fertilizer which promotes plant growth and improves soil quality. Vermicomposting is an economically feasible and environment friendly technology in which organic wastes are bio-converted into value added product and various organic wastes are used in this process. Terrestrial weeds are the plant species which grow on land and invasive in nature. These plants are responsible for various nuisances in the environment, agriculture and society. The weed biomass generated after various management methods are considered as organic waste. The terrestrial weed biomass is a possible option for the production of vermicompost. In this chapter scope of vermicompost for sustainable agriculture, the vemicomposting mechanism and the bioconversion of terrestrial weed biomass into vermicompost have been discussed.
Aneela Taj, Nusrat Jamil
Biomolecules · 2018
The biochemical potential of pathogenic bacteria may cause alteration in the neurophysiological environment; consequently, neuroendocrine and immune responses of the host are modulated by endogenously produced metabolic products of neuropathogenic bacteria. The present study was designed to detect the derived biogenic amines in spent culture media of Bacillus cereus (Bc), Clostridium tetani (Ct), Listeria monocytogenes (Lm), and Neisseria meningitidis (Nm). Overnight grown culture in different culture media i.e., Nutrient broth (NB), Luria basal broth (LB), Brain Heart Infusion broth (BHI), and human serum supplemented RPMI 1640 medium (RPMI) were used to prepare filter-sterilized, cell-free cultural broths (SCFBs) and subjected to high performance liquid chromatography with electrochemical detection (HPLC-EC) along with the control SCFBs. Comparative analysis of biogenic amines in neuropathogenic bacterial SCFBs with their respective control (SCFB) revealed the complete degradation of dopamine (DA) into its metabolic products by Bc, Ct, and Nm, whereas Lm showed negligible degradation of DA. A relatively high concentration of 5-hydroxyindol acetic acid (5HIAA) by Bc in NB and LB indicated the tryptophan metabolism by the serotonin (5HT) pathway. Our study suggests that microbial endocrinology could help unravel new perspectives to the progression of infectious diseases.
R. Pandey, T. Sohail, A. I. Ajibona et al.
57th U.S. Rock Mechanics/Geomechanics Symposium · 2023
ABSTRACT The total annual US consumption of natural gas is expected to surpass 40 trillion cubic feet in the coming years. Microbially enhanced coalbed methane (MECBM) aims to replicate naturally occurring microbial pathways to generate methane from in-situ coal. In a basic gamut of lab-characterization experiments investigating properties of coal as a reservoir, it was revealed microbial treatment of coal results in swelling of the coal matrix. Bio-strains in the matrix result in changes in connected porosity, and its stress-state which governs the flow behavior throughout the life of the producing reservoir. Use of molecular dynamics (MD) enables us to utilize the bio-strain data to understand the dynamic stress-state development in a MECBM reservoir. The Wiser coal molecule was used as the representative molecule, whose reactive potential was minimized using PCFF. The stable MD system enables application of strain, which enables the analysis of internal stresses. Results indicated internal stresses developed during bioconversion exceeded the Von Mises failure criterion for the sample tested in the laboratory under hydrostatic pressure (0.2 MPa). However, the internal stresses for sample under in-situ stress regimes was suppressed, far from the tensile failure conditions. INTRODUCTION AND BACKGROUND There has been a sustained increase in the demand for clean energy sources such as hydrogen and methane, especially as the world works towards meeting sustainable climate goals (Jun et al., 2016). Natural gases like methane have lower carbon footprint, as it generates approximately 50% of the carbon when compared to burning oil and coal for electricity generation (Tollefson, 2012). As such, natural gases are set to go up in production rates to meet environmental demands. Recent data indicates that the world demand for natural gas is expected to increase till 2045, with a significant portion of this demand to be met by increasing production from unconventional resources, such as coalbed methane (CBM) (Birol, 2017; Gonzales, 2021; IEA, 2022). CBM refers to naturally occurring methane extracted from coal and coal seams, which is an unconventional source of natural gas (Haldar, 2018). However, to meet the increasing demand for natural gas, researchers have made efforts to find ways to increase the production of coalbed methane. One such method is to replicate the natural production of methane formed by microbial breakdown of organic components present in coal (Flores et al., 2008; Strapoć et al., 2008; Midgley et al., 2010; Penner et al., 2010). This process of producing microbial methane from coal is referred to as Microbially Enhanced Coalbed Methane (MECBM) (Scott, 1999).
Chen Chang, Bo Liu, Yihong Bao et al.
Research Square · 2020
Abstract Background Phenylpropanoid including raspberry ketone, is a kind of important natural plant product and widely used in pharmaceuticals, chemicals, cosmetics, and healthcare products. Bioproduction of phenylpropanoid in Escherichia coli and other microbial cell factories is an attractable approach considering the low phenylpropanoid contents in plants. However, it is usually difficult to produce high titer phenylpropanoid production when fermentation using glucose as carbon source. Developing novel bioprocess using alternative sources might provide a solution to this problem. In this study, typical phenylpropanoid raspberry ketone was used as the target product to develop a biosynthesis pathway for phenylpropanoid production from fatty acids, a promising alternative low-cost feedstock. Results A raspberry ketone biosynthesis module was developed and optimized by introducing 4-coumarate-CoA ligase (4CL), benzalacetone synthase (BAS), and raspberry ketone reductase (RZS) in Escherichia coli strains CR1-CR4. Then strain CR5 was developed by introducing raspberry ketone biosynthesis module into a fatty acids-utilization chassis FA09 to achieve production of raspberry ketone from fatty acids feedstock. However, the production of raspberry ketone was still limited by the low biomass and unable to substantiate whole-cell bioconversion process. Thus, a process by coordinately using fatty-acids and glycerol was developed. In addition, we systematically screened and optimized fatty acids-response promoters. The optimized promoter Pfrd3 was then successfully used for the efficient expression of key enzymes of raspberry ketone biosynthesis module during bioconversion from fatty acids. The final engineered strain CR8 could efficiently produce raspberry ketone repeatedly using bioconversion from fatty acids feedstock strategy, and about 291.3 mg/L raspberry ketone was produced. Conclusion Metabolically engineered Escherichia coli strains were successfully developed for raspberry ketone production from fatty acids using several strategies, including optimization of bioconversion process and fine-tuning key enzyme expression. This study provides an essential reference to establish the low-cost biological manufacture of phenylpropanoids compounds.
Sergii Shamanskyi, Sergii Boichenko, Lesia Pavliukh
ScienceRise · 2020
The object of research: the process of wastewater treatment using bioconversion for subsequent motor fuel production. Investigated problem: improving the efficiency of bioconversion process for biofuel production with simultaneous wastewater treatment by removing nitrogen and phosphorous compounds. The main scientific results: providing the possibility of biofuel production with energy and economic inefficiency. It is done by combining the process of motor biofuel production with the process of treating wastewater from biogenic elements makes it perspective for commercial use. Traditional technology for the production of motor biofuels from microalgae includes cultivation, harvesting, dehydration and drying of biomass, extraction of oils from them and subsequent production of methyl esters and glycerol. Such technology is often not economically effective. It requires significant amount of energy for carrying out all necessary processes. In addition, it requires significant expenditures of water and nutrients. The use of nutrient-rich wastewater as a culture medium for the cultivation of microalgae allows not only to reduce costs, but also to purify wastewater from nitrogen and phosphorus compounds, which makes this process economically effective. The area of practical use of the research results: Sewage and gray water treatment plants. Industrial and agricultural effluents treatment plants. Different types of enterprises, which have wastewater enriched with nitrogen and phosphorous compounds. Innovative technological product: The technology of microalgae cultivation using wastewater as a culture medium. The technology allows effectively purifying used wastewaters from nitrogen and phosphorous compounds with no waste at the end. Scope of the innovative technological product: Improved technology of motor biofuel production with simultaneous wastewater purification, which is economically effective and environmentally safe.
Alfonso Timoneda, Arian Amirvaresi, Reza Ovissipour
bioRxiv (Cold Spring Harbor Laboratory) · 2024
Abstract Developing low-cost media is one of the major challenges in the cellular agriculture domain. Thus, this study aimed to develop low-cost media for cell-cultivated seafood using gut-microbial community-assisted fermentation. Black soldier fly larvae ( Hermetia illucens ) were used as the substrate and exposed to gut microbial communities isolated from Blue catfish ( Ictalurus furcatus ). In the first step, BSFL slurry was subjected to enzymatic digestion, using pepsin and trypsin to mimic animal digestive processes. The results showed a 2.8% degree of hydrolysis after digestion with pepsin and an additional 5.9% after digestion with trypsin. In the second step, two fermentation approaches were tested, including the direct addition of gut homogenate to the hydrolysates (fermentation A) and the establishment of microbial cultures from the gut homogenate before fermentation (fermentation B). Both fermentations resulted in similar protein content and degree of hydrolysis. Fermentation led to a decrease in species richness, with the loss of important chitinase and protease-producing genera such as Pseudomonas and Clostridiaceae. However, there was an increase in Paraclostridium and members of the Enterobacteriaceae. In addition, the effect of fermented hydrolysates from BSFL on the proliferation of zebrafish embryo fibroblasts was tested in comparison to fetal bovine serum (FBS) in in vitro cell cultivation. Lower concentrations of FBS resulted in decreased cell density and altered cell morphology. The supplementation of hydrolysate B at high peptide concentrations had cytotoxic effects on the cells, while at lower peptide concentrations, it improved cell proliferation only in cultures with 2.5% FBS.
Kamran Malik, Chunjie Li, Adnan Arshad
· 2025
Background: Appropriate bioprocessing of lignocellulosic materials into ethanol could address the world’s insatiable appetite for energy while mitigating greenhouse gases. Bioethanol is an ideal gasoline extender and is widely used in many countries in blended form with gasoline at specific ratios to improve fuel characteristics and engine performance. Finding a suitable microbial agent for the efficient conversion of lignocellulose is still an active field of study. Objective: To enhance the bioethanol production with effective lignin degradation and utilization of pentose and hexose sugars in an economical way. Methods: Ryegrass (Lolium perenne L.) biomass was the substrate. Microbial strains Bacillus mobilis, Bacillus velezensis, and Bacillus cereus, were isolated, identified, determined for their lignin degradation capability, and used as pretreatment agents for the lignin degradation. Various modern spectroscopic analyses, ligninolytic activity, sugar estimation, enzymatic hydrolysis, and liquefaction and fermentation process were conducted. The final data was statistically validated with post-hoc Tukey test, R software and SPSS Statistics 26.Results: The proximate and ultimate analyses of raw biomass showed that it comprised of total solids 96.54%, volatile solids 92.82%, carbon 48.22%, and sulphur 0.28%. After the application of bacterial pretreatments, the lignin content was considerably reduced to 6.78%, and the cellulose share increased to 57.31%. The LiP and MnP like activity was highest in alkaline lignin culture source with an amount of 0.67 ± 0.1 U/mL and 1.03 ± 0.08 U/mL, respectively. The optimum sugar utilization efficiency was reached at 93.46 %, with the highest bioethanol production of 0.51 g/g and 85.78 % bioethanol yield after the anaerobic fermentation.Conclusion: In this study, successful delignification of the ryegrass biomass was achieved by bacterial pretreatments and maximum bioethanol was produced. The integration of bacterial pretreatments and C5 and C6 sugar utilizing microbial strains could enhance the commercial bioethanol production. The ryegrass biomass was selected since it is a common agricultural waste in China. The transformation of this biomass into industrial products like ethanol, would not only utilize waste but also accord to environmental safety. However, to meet global energy demand further studies to develop sustainable and cost-effective approaches are still required.
Nalini Nalini, D. Jeyachitra
INDIAN JOURNAL OF APPLIED RESEARCH · 2025
The present study is aimed with an objective to produce bio ethanol from agrowaste. Paddy straw bio mass is collected from agricultural land and utilized as feed stock for ethanol production after subjecting them to acid, alkali and enzymatic pre treatments. Two bacterial strains (R2 and R3) and one yeast strain (S6) were isolated from soil samples collected from paddy field dumped with straw and from sugarcane bagasse dumped soil. In addition to this, cellulose degrading bacteria strain (C1) is isolated to carry out the enzymatic pre treatment. Based on the fermentation efficiency tested, S6, R2 and R3 strains were inoculated in eight different pretreated biomass filtrate medium for fermentation process. Ethanol concentration were quantified at a period of five days interval up to twenty days. Ethanol concentration increased from 5th day to 20th day and 5th day to 15th day in yeast and bacteria inoculated medium. After recovery through distillation, yeast strain S6 inoculated medium is reported with more concentration of ethanol in alkali pre treated bio mass filtrate medium. There is no significant difference between alkali pre treated biomass and combined alkali & enzyme pre treated bio mass inoculated with yeast strain at 0.001 level of significance. The overall product extracted is in the range of 5-12%. Ethanol extracted from yeast S6 is reported to have disinfectant effect against bacteria. FTIR spectrum analysis reported the presence of similar peaks to that of standard ethanol
Zhina Lian, Xin Zhou
Fermentation · 2024
Lignocellulosic biomass (LCB) offers numerous advantages as a sustainable energy resource, such as its abundance, degradability, environmental compatibility, non-toxic nature, and cost-effectiveness [...]
Kerisha Raghunandan
· 2013
The continual growth of the global biodiesel industry has resulted in a proportional increase in crude glycerol production. The by-production of glycerol waste during the manufacture of biodiesel has, with recent research, proven to hold use as a feedstock for the production of several commodity chemicals. The conversion of glycerol may be carried out by both chemical as well as biological means. The biological conversion of glycerol surpasses chemical conversion with respect to higher yield and selectivity, normal reaction conditions and the use of cheaper biological catalysts. Many microorganisms are known to convert glycerol to different value added products. This study involved the isolation of bacteria from soil and crude glycerol from a local biodiesel plant. Isolates were then used to convert crude glycerol supplemented with salts and a nitrogen source into commercially viable products. Isolates which successfully degraded glycerol were then identified via 16S PCR. A strain of Klebsiella pneumoniae, which is a known producer of 1,3-propanediol (1,3-PDO), was isolated from soil and two strains of Sphingomonas sp., which is a known gellan producer, was isolated from biodiesel waste. Gellan is an exopolysaccharide used in the food, cosmetic and pharmaceutical industries sold commercially as a product known as Gelrite or Gelzan while 1,3-PDO is an important component of fuels and polyesters (used widely in the petroleum industry) and is currently chemically produced. Using crude glycerol for producing 1,3-PDO is a good solution from an economic as well as ecological point of view. K. pneumoniae, Sphingomonas psueudosanguinis and Sphingomonas yabuuchiae were subjected to a series of shake flask fermentations in order to determine optimal growth conditions. This microoganism was able to successfully produce significant amounts of 1,3-PDO and lactic acid using crude glycerol (80 g/l), without pre-treatment (37 and 6.8 g/l respectively). S psueudosanguinis and S. yabuuchiae were both able to produce two of the highest amounts of gellan gum than that reported by other studies using crude glycerol (80 g/l) as a sole carbon source in a minimal medium (50.9 and 52.6 g/l respectively).
Carlos Martín
Agronomy · 2021
Decreasing the dependence on fossil resources as raw materials for the production of fuels, platform chemicals, and commodities is an imperative requirement of today’s industry and society in order to alleviate the threats related to climate change [...]
Z. Benattouche, K. Benamar, H. Belkhodja et al.
Romanian Journal of Infectious Diseases · 2024
Background. The Maillard product was prepared from four model systems (aminoacids-glucose) at pH 10 and 110°C for 120 mn. Aim. This study aims to investigate the antimicrobial potential of different Maillard products and their hemolytic effect. Methods. Maillard products were prepared by four models (Gly-glu), (Val-glu), (Try-glu) and (Asp-glu). The prepared Maillard product antimicrobial activity was tested at concentration of 0.24, 0.48, 0.97, 1.95 and 3.90 mg/ml against Escherichia coli ATCC 25923, Staphylococcus aureus ATCC 25922, Candida albicans and Fusarium graminearum) and hemolytic activity. Results. The inhibition diameter of the test isolate by-products from 4 models of Maillard reaction (Gly-glu), (Val-glu), (Try-glu), and (Asp-glu) ranged from 15±0mm to 28.3±0.4mm. The minimum inhibitory concentration (MIC) ranged from 0.97 mg/ml to 1.95 mg/ml for only two test isolates. Maillard reaction products also showed a similar effect of growth inhibition compared with antibiotics frequently used for treating bacterial infections. An evaluation of the hemolytic activity of the Maillard products on erythrocytes showed a low hemolysis rate of the order of 12.09%. Conclusion. The Maillard products tested had vigorous antimicrobial activity against some pathogenic microorganisms. The Maillard reaction product can be used as a narrow-spectrum antibiotic.
Valeriy Bekmuradov
· 2021
Production of biofuel such as ethanol from lignocellulosic biomass is a beneficial way to meet sustainability, energy security, and environmental goals. Lignocellulosic biomass such as source-separated organic (SSO) waste is particularly attractive since it is widely available, often at a negative cost, reduce the land depletion from using food-based biomass for ethanol production and reduce the amount of generated waste. Therefore, in order to meet the future fuel demands and cope with increasing volume of municipal waste this study was a first attempt to use SSO as a feedstock for ethanol production. The main objectives of the study were: a) to compare standard and modified celluloseorganic- solvent-based lignocellulosic fractionation (COSLIF) pretreatment of SSO waste for ethanol production in terms of enzyme savings, sugar formation and ethanol yields; b) to produce ethanol from SSO by using modified COSLIF pretreatment and fermentation with two different recombinant strains: Z. mobilis 8b and S. cerevisiae DA2416; and c) to develop experimental kinetic model capable of predicting behavior of batch SSCF on SSO waste with different SSO substrate concentrations using Berkeley Madonna program. Based on the obtained results, it was found that SSO is an excellent feedstock material for ethanol conversion. The efficiency of modified COSLIF pretreatment was improved by 20% compared to standard method using ethanol washing of pretreated SSO samples during the experimental procedures instead of acetone. On average, glucose yield from SSO samples pretreated by modified COSLIF was about 90% compared to 10% for untreated samples. S. cerevisiae DA2416 outperformed Z. mobilis 8b on ethanol yields during the fermentation process, with 0.50 g ethanol/g potential sugar fed on SSO in less than 5 days, with a 96% cellulose conversion, totalling in 150 g/L ethanol produced. A kinetic model with newly integrated values of experimentally defined SSO feedstock constants was proven to predict the ethanol yield accurately with substrate concentration ranges of 20 g/L - 50 g/L. Model prediction at higher substrate concentration (e.g. 100 g/L) deviated from the experimental values, suggesting that ethanol inhibition is a major factor in bioethanol conversion.
Ryan Davis, Mary Biddy, Eric C. D. Tan et al.
· 2013
In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates the biological conversion of biomass derived sugars to hydrocarbon biofuels, utilizing data from recent literature references and information consistent with recent pilot scale demonstrations at NREL. Technical barriers and key research needs have been identified that should be pursued for the pathway to become competitive with petroleum-derived gasoline, diesel and jet range hydrocarbon blendstocks.
L. Lynd, G. Beckham, A. Guss et al.
Energy & Environmental Science · 2022
Hybrid processes, featuring biological conversion of lignocellulose to small molecules followed by chemo-catalytic conversion to larger molecules suitable for difficult-to-electrify transport modes, are a promising route to biomass-derived fuels in demand for climate stabilization.
J. Hyeon, S. W. Kim, Chulhwan Park et al.
Chemical Communications · 2015
An enzyme complex for biological conversion of CO to CO2 was anchored on the cell surface of the CO2-utilizing Ralstonia eutropha and successfully resulted in a 3.3-fold increase in conversion efficiency. These results suggest that this complexed system may be a promising strategy for CO2 utilization as a biological tool for the production of bioplastics.
Xiaolu Wang, Yu Wang, Jiao Liu et al.
Bioresources and Bioprocessing · 2017
BackgroundMethanol is regarded as a biorenewable platform feedstock because nearly all bioresources can be converted into methanol through syngas. Biological conversion of methanol using synthetic methylotrophs has thus gained worldwide attention.ResultsHerein, to endow Escherichia coli with the ability to utilize methanol, an artificial linear methanol assimilation pathway was assembled in vivo for the first time. Distinct from native cyclic methanol utilization pathways, such as ribulose monophosphate cycle, the linear pathway requires no formaldehyde acceptor and only consists of two enzymatic reactions: oxidation of methanol into formaldehyde by methanol dehydrogenase and carboligation of formaldehyde into dihydroxyacetone by formolase. After pathway engineering, genome replication engineering assisted continuous evolution was applied to improve methanol utilization. 13C-methanol-labeling experiments showed that the engineered and evolved E. coli assimilated methanol into biomass.ConclusionsThis study demonstrates the usability of the linear methanol assimilation pathway in bioconversion of C1 resources such as methanol and methane.
Jonas A. Ohlsson, A. Harman-Ware, M. Sandgren et al.
BioEnergy Research · 2019
Biomass recalcitrance, the inherent resistance of plants towards deconstruction, negatively affects the viability of biorefineries. This trait is not only dictated by the properties of the biomass but also by the conversion system used and its interactions with specific features of the biomass. Here, biomass recalcitrance to anaerobic digestion (AD) was assessed using a biomethanation potential (BMP) assay. Plant material ( n = 94) was selected from a large population of natural Salix viminalis accessions, previously evaluated for biomass recalcitrance using hydrothermal pretreatment–enzymatic hydrolysis. Correlations between yields from the two biological conversion systems were evaluated, as well as the influence of biomass compositional features, analyzed by pyrolysis-molecular beam mass spectrometry (py-MBMS), and other biomass physical properties on conversion performance. BMP values averaged 198.0 Nml CH 4 /g biomass after 94 days, ranging from 28.6 to 245.9. S lignin and carbohydrate-derived spectral features were positively correlated with performance under both systems, whereas G lignin, p -coumaric acid, and ferulic acid-derived ions were negatively correlated with yields and rates. Most spectral features were more strongly correlated with enzymatic hydrolysis yields compared to methane production. For early-stage methane production and rate, recalcitrance factors were similar compared to enzymatic hydrolysis, with weaker correlations observed at later timepoints. The results suggest that although variation in methane potential was considerably lower than enzymatic hydrolysis yields, a reduced recalcitrance under this system will still be of importance to improve early conversion rates. Spectral features of low methane-producing samples indicate the presence of inhibitory substances, warranting further study.
R. Kumar, S. Bhagia, M. Smith et al.
Green Chemistry · 2018
It has been previously shown that cellulose-lignin droplets’ strong interactions, resulting from lignin coalescence and redisposition on cellulose surface during thermochemical pretreatments, increase cellulose recalcitrance to biological conversion, especially at commercially viable low enzyme loadings. However, information on the impact of cellulose–hemicellulose interactions on cellulose recalcitrance following relevant pretreatment conditions are scarce. Here, to investigate the effects of plausible hemicellulose precipitation and re-association with cellulose on cellulose conversion, different pretreatments were applied to pure Avicel® PH101 cellulose alone and Avicel mixed with model hemicellulose compounds followed by enzymatic hydrolysis of resulting solids at both low and high enzyme loadings. Solids produced by pretreatment of Avicel mixed with hemicelluloses (AMH) were found to contain about 2 to 14.6% of exogenous, precipitated hemicelluloses and showed a remarkably much lower digestibility (up to 60%) than their respective controls. However, the exogenous hemicellulosic residues that associated with Avicel following high temperature pretreatments resulted in greater losses in cellulose conversion than those formed at low temperatures, suggesting that temperature plays a strong role in the strength of cellulose–hemicellulose association. Molecular dynamics simulations of hemicellulosic xylan and cellulose were found to further support this temperature effect as the xylan–cellulose interactions were found to substantially increase at elevated temperatures. Furthermore, exogenous, precipitated hemicelluloses in pretreated AMH solids resulted in a larger drop in cellulose conversion than the delignified lignocellulosic biomass containing comparably much higher natural hemicellulose amounts. Increased cellulase loadings or supplementation of cellulase with xylanases enhanced cellulose conversion for most pretreated AMH solids; however, this approach was less effective for solids containing mannan polysaccharides, suggesting stronger association of cellulose with (hetero) mannans or lack of enzymes in the mixture required to hydrolyze such polysaccharides.
Nawa Raj Baral, Eric Sundstrom, Lalitendu Das et al.
ACS Sustainable Chemistry & Engineering · 2019
The future bioeconomy promises drop-in or performance-advantaged biofuels and bioproducts derived from lignocellulosic biomass, substantial greenhouse gas emissions reductions in sectors with few or no alternatives, and increased domestic energy production in countries with sufficient biomass resources. Despite the slower than anticipated pace of commercializing next-generation biofuels, the research community continues to make dramatic improvements at every stage of production, from feedstock cultivation through conversion to final products. However, the interdisciplinary nature of bioenergy research, and the need for cross-coordination among biologists, chemists, agronomists, and engineers, make coordinating and optimizing these strategies challenging. This Perspective surveys recent advancements in bioenergy crop engineering, lignocellulosic biomass deconstruction and fractionation, catabolism of biomass-derived sugars and aromatics, and biological conversion to fuels and products. We organize major re...
Xu Wei, J. Pandohee, Baojun Xu
Critical Reviews in Food Science and Nutrition · 2023
Abstract This review elaborates on biochemical characteristics, in vivo metabolism, biological conversion through UV irradiation, as well as dietary fortification of vitamin D. Recent innovations in vitamin D utilization, including nanoencapsulation, direct or indirect addition, emulsion, ultrasound, microwave processing, CRISPR-Cas9 genome editing, as well as UV photoconversion, were summarized. Mushrooms, eggs, yeasts, as well as seafood, such as Barramundi and Atlantic salmon, were typical representatives of original natural food materials for vitamin D bioconversion in relevant research. The critical session thereof referred to the 295 nm UV-B irradiation triggering biological fortification of vitamin D2 and vitamin D3, which occurred in ergosterol from mushrooms, and cholesterol from egg yolk, respectively. The schematic biosynthesis of vitamin D precursors in yeasts regulated miscellaneous enzymes were clearly demonstrated. These summarized pathways played a role as a theoretical primer for vitamin D bioconversion when the UV irradiation technique is concerned. Besides, tomatoes had become the latest potential vitamin D sources after genetic modification. The safety consideration for vitamin D fortified functional food was discussed either. Further research is required to fill the gap of investigating optimized factors like types of eggs, meat, and grain, boarder range of wavelength, and dosage in UV irradiation. Vitamin D has a great potential market in the field of functional food development.
Stetson S. Bassett, Eva C. Nieminski, David K. Stevens
AWWA Water Science · 2019
The purpose of this study was to evaluate water quality and operational trends of a side‐by‐side, full‐scale biofiltration conversion. Four filters at a water treatment plant, treating low turbidity and low total organic carbon water, were monitored for one year. One filter was a prechlorinated control, and the other three were biofilters. One was a standard biofilter, one had chlorinated backwash, and the third was supplemented with nutrients. Slightly higher concentrations of adenosine triphosphate (ATP) (175–2,300 ng ATP/cm 3 ) and extracellular polymeric substances (0.00–0.08 mg glucose/g total solids) were found in the biofilters compared with the control. Total trihalomethanes and haloacetic acid were lower in the biofilters relative to the control (60 and 30%, respectively). Conversion to biological filtration resulted in slightly higher (0.019 ntu) and more variable (0.013 ntu) effluent turbidity, but filter run volumes were unaffected. At the conclusion of the study, a decision was made to convert all the filters in the plant to biofilters.
Agampodi Sunil Shanta Mendis, Shashiprabha Punyakantha Dunuweera, Shanta Walpolage et al.
Detritus · 2020
Conversion of the sludge generated in the biological treatment plants of glove dipping industries of Sri Lanka to a valuable organic fertilizer after removing toxic metal ions such as heavy metals and excess Zn and Al present in the sludge to allowable limits is described. In order to do so, the raw materials used were analysed for these species and for their nutritional values. Removal of metal ions by different acids such as HNO3 and acetic acid digestion processes are revealed and the results are compared. Dilution of the metal ion-removed sludge with other raw materials used in organic fertilizer production to enable maintain right C:N ratio and the use of these materials in the fertilizer production process used are presented. Application of the fertilizer to soils of fruit and vegetable plantations and measurement of Zn, Al and heavy metals in the soil and plant parts and their crops as a function of time is also described. The quality of vegetables and fruits produced by applying this new fertilizer is compared with those obtained in the open market.It has been shown that the former contains no or much less than maximum allowable limits of heavy metals or toxic species when compared to those grown using other organic fertilizers. This study is useful for industrial biological treatment plant sludge management by converting it to a useful product.
Jinwoo Yang, Junsoo Lee
The FASEB Journal · 2018
Flavonoids attract much attention due to their various physiological properties and these compounds naturally exist as their glycoside forms. Rutin, one of the most abundant flavonoids in nature, is composed of the aglycone quercetin and the disaccharide rutinose. Although, there is a structural similarity in rutin and quercetin, there are some obvious differences in physical, chemical, and biological characters. It is reported that quercetin has a higher biological activity than other glycosidic quercetin derivatives. Thus, de‐glycosylation of rutin would be an important process for enhanced biological activities. Therefore, in this study, to convert rutin to quercetin, the effects of acid concentrations and solvents were investigated and biological activities were evaluated. As a results, when 80 % ethanol was used, the hydrolysis of rutin was more rapid than water as solvent for reaction. Hydrolysis of rutin was also accelerated as the acid concentration increased from 0.1 to 1.0 M of HCl. Anti‐oxidant, anti‐inflammatory, and anti‐adipogenic activities were increased with the increased conversion rate of rutin to quercetin. These results suggest that the acid treatment can be used as a process to improve the physiological activity of glycoside flavonoids. This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal .
P Timms, IC MacRae
Australian Journal of Biological Sciences · 1982
In a detailed study it was shown that washed cell suspensions of K. pneumoniae reduced the organophosphorus pesticide fensulfothion to fensulfothion sulfide. Temperature and pH optima for this conversion plus sensitivity to sulfydryl-reacting agents strongly suggested enzyme involvement. The reaction was also quite sensitive to molecular oxygen, only proceeding under conditions of low oxygen tension. Once formed, the fensulfothion sulfide was rapidly bound by living and heat-killed cells. A combination of lysozyme treatment and differential centrifugation showed 90 % of the sulfide to be concentrated in the cell membrane fraction of exposed cells.
Anke Wolthoorn, Simon Kuitert, Henk Dijkman et al.
Advanced Materials Research · 2007
In a bench scale trial biological sulfate reduction was applied to convert anglesite (PbSO4) to galena (PbS). Anglesite is a main constituent of waste fractions such as the residue from an indirect leaching process or in lead paste from spent car batteries. The goal of this study was to develop a technology to decrease the lead (Pb) emissions by converting PbSO4 from a waste fraction into PbS, which can be recovered from the waste fraction using a flotation process or an electrochemical process. The conversion of anglesite to galena is based on the biological sulfate reduction process and a metal precipitation process. First sulfate is biologically reduced to sulfide. Secondly, the Pb2+ from the PbSO4 reacts chemically with the sulfide resulting from the first reaction. A bench-scale reactor was started up using sulfate- and sulfur-containing influent. The reactor was seeded with biocatalyst from several full-scale reactors. Anglesite-containing residue was added batch-wise when the formation of sulfide started. The residue contained mainly PbSO4 (51.7%), sulfate (SO4 2-, 19.9%) and elemental sulfur (S0, 15.1%). Galena precipitates in the bioreactor due to the near-neutral pH at which sulfate reduction is carried out. During the experiment a surplus of sulfide relative to Pb was maintained to prevent the formation of PbCO3 and the accompanying pH decrease that would unavoidable result in the inhibition of the biocatalyst. Both sulfate and sulfur present in the residue were biologically reduced. The formation of PbS was confirmed by the increased Pb:O ratio of the sludge (1:0.03) relative to the Pb:O ratio of the residue (1:0.3). A potential large-scale application is proposed.
Po Min Li, Ching Wei Lee, Jhan Shan Lin
Advanced Materials Research · 2011
Lignocellulose is one of the richest biological resources on earth. Yet, due to the robust structure, lignocelluloses are still not effectively utilized. This research adopted the fungi from the nature— Corilus versicolor —to culture and destroy the lignocellusic structure. The object of the research was banana stalks, a common Taiwan agricultural waste. The banana stalks were physically pretreated to banana wood flour before use. Through changes of the grains’ sizes of the banana wood flour, and proportions of the compounded carbons of the banana wood flour in the media, the optimal degradation activity was determined. The result showed that on the 12 th day the 5mm grains used to replace the compounded carbons reached the maximal microbial activity, 70 times of a general medium. On the 14 th day near 18% of celluloses were consumed by white-rot fungi. The result has contribution to lignocellulosic structure breakdown and a great step for energy conversion in subsequent stage.
John M. Woodley
Reaction Chemistry & Engineering · 2020
Reaction engineering needs to embrace biological conversion technologies, on the road to identify more sustainable routes for chemical manufacture.
YANG WANG, SHIJIE LIU
TAPPI Journal · 2012
Woody biomass is an important alternative source for chemicals, materials, and energy. Although different routes of woody biomass conversion have been proposed in various studies, typical biochemical production processes using woody biomass feedstocks consist of four major steps: pretreatment, hydrolysis, fermentation, and separation. Pretreatment remains the most important step in biomass conversion. This paper is a review of available pretreatment technologies for woody biomass bioconversion.
Ryuji Ohue, Kei Hashimoto, Masahiro Nakamoto et al.
Journal of Innate Immunity · 2011
Recent publications report that heat shock proteins (HSPs) can endow regulatory responses to the systemic immune system when administered via the mucosal route, leading to an amelioration of atherosclerosis and allergy. However, it remains poorly understood if HSP antigens exist in the luminal contents of the gastrointestinal tract and which types of HSP induce regulatory responses. Here we addressed these problems, considering that numerous gut microflora and foods are natural sources of HSPs. SDS-PAGE and immunoblotting with the anti-HSP60 antibody demonstrated the intact and degraded forms of HSP60 mainly in appendix and large intestine of the gastrointestinal tract. No reactivity with this antibody was observed for any of the luminal contents derived from germ-free animals, suggesting gut microflora to be a source of the intestinal HSPs because of lack of HSPs in animal chow diet. GroEL, a typical member of bacterial HSP60, showed a tendency to stimulate splenocytes in germ-free mice, compared to that in conventional mice, suggesting that resident commensal bacterial GroEL may stimulate HSP-reactive T cells as regulatory cells in conventional animals. Importantly, GroEL, but not mouse-derived HSP60, caused naïve T cells to differentiate into CD4+ CD25+ Foxp3+ T cells, indicating that the production of regulatory T cells depends on the type of HSP. Thus, HSPs derived from commensal microbes can be utilized to stimulate immunoregulatory pathways for the maintenance of intestinal homeostasis.
A. W. Khan, Duncan Wall, L. van den Berg
Applied and Environmental Microbiology · 1981
A simple procedure that uses a cellulose-enriched culture started from sewage sludge was developed for producing cellulolytic enzymes and converting cellulose to acetic acid rather than CH 4 and CO 2 . In this procedure, the culture which converts cellulose to CH 4 and CO 2 was mixed with a synthetic medium and cellulose and heated to 80°C for 15 min before incubation. The end products formed were acetic acid, propionic acid, CO 2 , and traces of ethanol and H 2 . Supernatants from 6- to 10-day-old cultures contained 16 to 36 mM acetic acid. Cellulolytic enzymes in the supernatant were stable at 2°C under aerobic conditions for up to 4 weeks and had the ability to hydrolyze carboxymethyl cellulose, a microcystalline cellulose, cellobiose, xylan, and filter paper to reducing sugars.
Rahul Saxena, Sona Vasudevan, Digvijay Patil et al.
International Journal of Molecular Sciences · 2015
DnaA oligomerizes when bound to origins of chromosomal replication. Structural analysis of a truncated form of DnaA from Aquifex aeolicus has provided insight into crucial conformational differences within the AAA+ domain that are specific to the ATP- versus ADP- bound form of DnaA. In this study molecular docking of ATP and ADP onto Escherichia coli DnaA, modeled on the crystal structure of Aquifex aeolicus DnaA, reveals changes in the orientation of amino acid residues within or near the vicinity of the nucleotide-binding pocket. Upon limited proteolysis with trypsin or chymotrypsin ADP-DnaA, but not ATP-DnaA generated relatively stable proteolytic fragments of various sizes. Examined sites of limited protease susceptibility that differ between ATP-DnaA and ADP-DnaA largely reside in the amino terminal half of DnaA. The concentration of adenine nucleotide needed to induce conformational changes, as detected by these protease susceptibilities of DnaA, coincides with the conversion of an inactive bacterial origin recognition complex (bORC) to a replication efficient pre-replication complex (pre-RC) at the E. coli chromosomal origin of replication (oriC).
Larisa Lee-Cruz, David P. Edwards, Binu M. Tripathi et al.
Applied and Environmental Microbiology · 2013
ABSTRACT Tropical forests are being rapidly altered by logging and cleared for agriculture. Understanding the effects of these land use changes on soil bacteria, which constitute a large proportion of total biodiversity and perform important ecosystem functions, is a major conservation frontier. Here we studied the effects of logging history and forest conversion to oil palm plantations in Sabah, Borneo, on the soil bacterial community. We used paired-end Illumina sequencing of the 16S rRNA gene, V3 region, to compare the bacterial communities in primary, once-logged, and twice-logged forest and land converted to oil palm plantations. Bacteria were grouped into operational taxonomic units (OTUs) at the 97% similarity level, and OTU richness and local-scale α-diversity showed no difference between the various forest types and oil palm plantations. Focusing on the turnover of bacteria across space, true β-diversity was higher in oil palm plantation soil than in forest soil, whereas community dissimilarity-based metrics of β-diversity were only marginally different between habitats, suggesting that at large scales, oil palm plantation soil could have higher overall γ-diversity than forest soil, driven by a slightly more heterogeneous community across space. Clearance of primary and logged forest for oil palm plantations did, however, significantly impact the composition of soil bacterial communities, reflecting in part the loss of some forest bacteria, whereas primary and logged forests did not differ in composition. Overall, our results suggest that the soil bacteria of tropical forest are to some extent resilient or resistant to logging but that the impacts of forest conversion to oil palm plantations are more severe.