Bacteria In Media Research Articles

Improved Adhesion of Bacterial Cellulose on Plasma-Treated Cotton Fabric for Development of All-Cellulose Biocomposites

Cellulose produced by bacteria (BC) is considered a promising material for the textile industry, but the fragile and sensitive nature of BC membranes limits their broad applicability. Production of all-cellulose biocomposites, in which the BC is cultivated in situ on a cotton fabric, could solve this problem, but here a new issue arises, namely poor adhesion. To overcome this challenge, cotton fabric was modified with low-pressure oxygen plasma in either afterglow, E-mode, or H-mode. All-cellulose biocomposites were prepared in situ by placing the samples of cotton fabric in BC culture medium and incubating for 7 days to allow BC microfibril networks to form on the fabric. Modification of cotton fabric with oxygen plasma afterglow led to additional functionalization with polar groups, and modification with oxygen plasma in H-mode led also to etching and surface roughening of the cotton fibers, which improved the adhesion within the biocomposite. In addition, these biocomposites showed higher deformation capacities. Modification of the cotton fabric over a longer period in E-mode was found to be unsuitable, as this caused strong etching, which led to the defibrillation of cotton fibers and poor adhesion of BC. This study highlights the potential of low-pressure plasma treatment as an environmentally friendly method to improve the performance of cellulose-based biocomposites.

Butyrate-producing bacteria as probiotic supplement: beneficial effects on metabolism and modulation of behaviour in an obesity mouse model.

Obesity is a risk factor for cardio-metabolic and neurological disease. The contribution of gut microbiota to derangements of the gut-brain axis in the context of obesity has been acknowledged, particularly through physiology modulation by short-chain fatty acids (SCFAs). Thus, probiotic interventions and administration of SCFAs have been employed with the purpose of alleviating symptoms in both metabolic and neurological disease. We investigated the effects of four butyrate-producing bacteria from the Lachnospiraceae family on the development of metabolic syndrome and behavioural alterations in a mouse model of diet-induced obesity. Male mice were fed either a high-fat diet (HFD) or an ingredient-matched control diet for 2 months, and bacteria cultures or culture medium were given by gavage to HFD-fed mice every second day. Mice were assessed through a battery of metabolic and behaviour tests, and fluxes through the gut barrier and blood-brain barrier were determined using Dextran-based tracers. One of the administered bacteria from the Coprococcus genus, which produces butyrate and formate, afforded some degree of protection against the development of obesity and its complications. Results from this study, however, are insufficient to support brain health benefits of the bacteria tested. None of the bacteria modulated permeability through the gut or blood-brain barriers. Our results suggest health benefits of a bacteria from Lachnospiraceae family, and encourage further exploration of its use as probiotic.

Antimicrobial Potential of Brassica oleracea Extracts (White and Broccoli) and Their Resistance Compared to Doxycycline Against Gram-Positive and Gram-Negative Bacteria.

Brassica oleracea L is low in carbohydrates and fiber, making it ideal for low-carb diets. But they are rich in vitamins, minerals, and other essential nutrients. The present article investigated the antimicrobial effect of B. oleracea extract (white and broccoli) (BOE-WB) on Gram-positive and Gram-negative strains and its resistance to doxycycline. BOE-WB was used as the soaking method. It was analyzed by gas chromatography-mass spectroscopy (GC-MS), high-performance liquid chromatography (HPLC), and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) methods. The samples were prepared with three concentrations. It used Mueller Hinton Agar culture medium of fresh bacteria. It was incubated for 24 h in a 37°C incubator. It identified 33 compounds. For BOE-W, 77% of the compounds are oxygenated, while for BOE-B, this percentage is 79%. For BOE-B, 79% had oxygenated compounds. BOE-WB has significant antibacterial effects on Pseudomonas aerogenosa and Bacillus cereus. The lethal impact of BOE-WB on strains is very close to that of doxycycline, and it can be introduced as a new antimicrobial drug to the medical world. The research shows that the percentage of oxygenated compounds in foods containing BOE-B is much higher than that of BOE-W. It has a significant impact on the antioxidant effect. Foods containing BOE-W have a high percentage of azo compounds and sulfur. One of the benefits of sulfur in the body is disinfecting the blood. In addition, sulfur increases the body's resistance to bacteria.

Exploiting Differential Signal Filtering (DSF) and Image Structure Filtering (ISF) Methods for Untargeted Mass Spectrometry Imaging of Bacterial Metabolites.

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) is a label-free technique, producing images where pixels contain mass spectra. The technique allows the visualization of the spatial distribution of (bio)molecules from metabolites to proteins, on surfaces such as tissues sections or bacteria culture media. One particularly exciting example of MALDI-MSI use rests on its potential to localize ionized compounds produced during microbial interactions and chemical communication, offering a molecular snapshot of metabolomes at a given time. The huge size and the complexity of generated MSI data make the processing of the data challenging, which requires the use of computational methods. Despite recent advances, currently available commercial software relies mainly on statistical tools to identify patterns, similarities, and differences within data sets. However, grouping m/z values unique to a given data set according to microbiological contexts, such as coculture experiments, still requires tedious manual analysis. Here we propose a nontargeted method exploiting the differential signals between negative controls and tested experimental conditions, i.e., differential signal filtering (DSF), and a scoring of the ion images using image structure filtering (ISF) coupled with a fold change score between the controls and the conditions of interest. These methods were first applied to coculture experiments involving Escherichia coli and Streptomyces coelicolor, revealing specific MS signals during bacterial interaction. Two case studies were also investigated: (i) cellobiose-mediated induction for the pathogenicity of Streptomyces scabiei, the causative agent of common scab on root and tuber crops, and (ii) iron-repressed production of siderophores of S. scabiei. This report proposes guidelines for MALDI-MSI data treatment applied in the case of microbiology contexts, with enhanced ion peak annotation in specific culture conditions. The strengths and weaknesses of the methods are discussed.

Competitive fitness and stability of ammonium-excreting Azotobacter vinelandii strains in the soil

Non-symbiotic N2-fixation would greatly increase the versatility of N-biofertilizers for sustainable agriculture. Genetic modification of diazotrophic bacteria has successfully enhanced NH4+ release. In this study, we compared the competitive fitness of A. vinelandii mutant strains, which allowed us to analyze the burden of NH4+ release under a broad dynamic range. Long-term competition assays under regular culture conditions confirmed a large burden for NH4+ release, exclusion by the wt strain, phenotypic instability, and loss of the ability to release NH4+. In contrast, co-inoculation in mild autoclaved soil showed a much longer co-existence with the wt strain and a stable NH4+ release phenotype. All genetically modified strains increased the N content and changed its chemical speciation in the soil. This study contributes one step forward towards bridging a knowledge gap between molecular biology laboratory research and the incorporation of N from the air into the soil in a molecular species suitable for plant nutrition, a crucial requirement for developing improved bacterial inoculants for economic and environmentally sustainable agriculture.Key points• Genetic engineering for NH4+ excretion imposes a fitness burden on the culture medium• Large phenotypic instability for NH4+-excreting bacteria in culture medium• Lower fitness burden and phenotypic instability for NH4+-excreting bacteria in soil

Bacillus megaterium: Evaluation of Chemical Nature of Metabolites and Their Antioxidant and Agronomics Properties.

Bacillus megaterium is particularly known for its abundance in soils and its plant growth promotion. To characterize the metabolites excreted by this specie, we performed successive liquid/liquid extractions from bacteria culture medium with different polarity solvents (cyclohexane, dichloromethane, ethyl acetate and butanol) to separate the metabolites in different polarity groups. The extracts were characterized regarding their total phenolic content, the amount of reducing sugar, the concentration of primary amines and proteins, their chromatographic profile by HPLC-DAD-ELSD and their chemical identification by GC-MS. Among the 75 compounds which are produced by the bacteria, 19 identifications were for the first time found as metabolites of B. megaterium and 23 were described for the first time as metabolites in Bacillus genus. The different extracts containing B. megaterium metabolites showed interesting agronomic activity, with a global inhibition of seed germination rates of soya, sunflower, corn and ray grass, but not of corn, compared to culture medium alone. Our results suggest that B. megaterium can produce various metabolites, like butanediol, cyclic dipeptides, fatty acids, and hydrocarbons, with diverse effects and sometimes with opposite effects in order to modulate its response to plant growth and adapt to various environmental effects. These findings provide new insight into bioactive properties of this species for therapeutic uses on plants.

Comparison of the Intensity of Biofilm Production by Oral Microflora and Its Adhesion on the Surface of Zirconia Produced in Additive and Subtractive Technology: An In Vitro Study.

This in vitro study set out to find out how well oral cavity-dwelling bacteria can form biofilms and adhere on the surfaces of zirconium oxide samples created by 3D printing and milling technologies. 5 strains of microorganisms were used for the study, and 40 zirconium oxide samples were prepared, which were divided into two groups (n = 20)-20 samples produced using removal technology comprised the control group, while 20 samples produced by 3D printing technology comprised the test group. The prepared samples were placed in culture media of bacteria and fungi that naturally occur in the oral cavity. Then, the intensity of biofilm build-up on the samples was determined using qualitative and quantitative methods. The results for both materials were compared with each other. No variations in the degree of biofilm deposition on zirconium oxide samples were found for the microorganisms Streptococcus mutans, Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus. For Candida albicans fungi, more intense biofilm deposition was observed on samples made using 3D printing technology, but these differences were not statistically significant. The biofilm accumulation intensity of ceramics produced by additive technology is comparable to that of milled zirconium oxide, which supports the material's broader use in clinical practice from a microbiological perspective. This ceramic has demonstrated its ability to compete with zirconium oxide produced by milling techniques in in vitro experiments, but sadly, no in vivo tests have yet been found to determine how this material will function in a patient's oral cavity.

An In Vitro Study on the Antimicrobial Effect of Fumigation with Jatu-Sarjarasadi Choorna

In the present scenario, shooting incidence of airborne diseases is a major public health challenge. Therefore, disinfecting our immediate surroundings is quite important. In Ayurveda, Dhoopana is a disinfection method by which drugs of herbal, herbo-mineral or animal origin are used for fumigation. It is a safe, natural and cost-effective method for disinfection. But the effectiveness of Dhoopana has to be proved scientifically for the acceptance of the modern society. Therefore, Jatu-sarjarasadi dhoopa yoga mentioned in Ashtanga samgraha sutrasthana is selected for the study to evaluate its antimicrobial activity. Jatu, Sarjarasa, Ushira, Sarshapa, Patra, Valaka, Vella, Arushkara, Pura, Arjuna are the ten ingredients of the yoga, among which Arushkara is replaced in this study with its Abhava dravya Citraka due to safety reasons. The study was conducted in the procedure room of Prasootitantra Department of Government Ayurveda College Hospital, Tripunithura. The room was fumigated for 30 minutes and kept enclosed for 24 hours. Total microbial colonies were estimated by settle plate method. Petridishes containing culture medium of bacteria and fungi were exposed for 60 minutes in the room before fumigation and 24 hours after fumigation. The sample plates were incubated and total microbial colonies before and after fumigation were counted. The data was statistically analysed using Wilcoxon Signed Rank Test. On statistical analysis, the reduction in total colony count of bacteriae and fungi was found to be significant and showed profound anti-bacterial activity when compared to anti-fungal action. The study concluded that fumigation with Jatu-sarjarasadi choorna has anti-microbial effect.

Cultivation of Microorganisms in Media Supplemented with Mucin Glycoproteins.

To examine the mucin-utilizing capacity of bacterial isolates from fecal samples, an in vitro cultivation method using mucins as a carbon source should be considered. This chapter describes a practical method for cultivating bacteria in media containing mucin glycoproteins; for this cultivation method, several factors are considered due to the physical nature of mucin glycoproteins.

Tinjauan Vibrio Vulnificus sebagai Ancaman Emerging Foodborne Disease pada Makanan Laut Segar

Vibrio vulnificus is a crucial foodborne opportunistic pathogen that can cause wound infections, septicemia, and gastroenteritis with a 50% fatality rate. This bacteria occurs in estuaries and coastal waters and is found in large quantities in oysters and other mollusc shells. The increasing number of foodborne diseases worldwide is suspected to have occurred due to the expansion of the international food trade. Consumption of raw seafood, especially oysters containing Vibrio vulnificus bacteria, can result in acute, severe systemic infections and is responsible for 95% of deaths from seafood consumption in the United States. The diagnosis of Vibrio vulnificus infection is confirmed by the growth of the bacteria in culture media from wounds, feces or blood. This article discusses the characteristics of the bacteria, host, environment, transmission, pathogenesis, clinical symptoms, diagnostic techniques and geographical distribution of V. vulnificus.

Optimation of Green Synthesis Biopolymer Cellulose Using Acetobacter xylinum From Whey as Media of Bacteria

Utilizing waste into a more valuable commodity was one of the objectives of that research. Waste which initially became an environmental pollutant factor could be processed into more useful products. Tofu liquid waste was referred to whey was a by-product of tofu production. Whey was waste that still contains organic materials such as protein, fat, carbohydrates and minerals. That whey was used as a growth medium for Acetobacter xylinum bacteria and produces cellulose biopolymer as a result of carbohydrate fermentation. The process of optimizing carbohydrate fermentation by Acetobacter xylinum bacteria was carried out by varying the ratio of the amount of whey to coconut water, the acidity level of the media, and the fermentation time. The research results showed that the biosynthesis of cellulose biopolymer was obtained from a ratio of whey concentration to coconut water of 1:1, variations in acidity levels showed that the optimum fermentation conditions occurred at pH 4, and the optimal amount of cellulose biopolymer was obtained on day 21, namely with the highest percent yield value. The resulting biocellulose was characterized using FTIR, XRD, and SEM. The characterization results show that biocellulose is well formed with a fiber surface shape and particle size in the range of 50-200 nm

Enhanced biodegradation kinetics in the copper-polluted sediment through bioaugmentation with water spinach and peanut husk-derived biochar

Stenotrophomonas maltophilia is a copper-tolerant bacterium that is used for improving the resilience and efficacy of microorganisms engaged in degrading substrate under high copper contamination. Examination of reaction kinetics indicates that the original consortia, Stenotrophomonas maltophilia and the mixed culture, follow a first-order reaction. The Michaelis-Menten model suggests that elevated copper concentrations exert stress on the original bacterial population and Stenotrophomonas maltophilia. However, when a mixed culture is employed during the bioaugmentation process, it brings about an enhancement in microbial resistance and performance. This study demonstrates that the poor performance of indigenous bacteria in media that are highly contaminated with copper can be improved by adding exogenous copper-tolerant bacteria. Furthermore, poor mass transfer in sediments can be improved by adding plants and biochar. This strategic addition serves a dual purpose: it increases the affinity of the substrate for sediments characterized by poor mass transfer and alleviates the inhibitory effects induced by copper. In addition, high percentages of Firmicutes, Bacteroidetes, and Euryarchaeota within the biochar matrix were verified to expedite the substrate biodegradation process even at high copper concentrations. The findings in this work provide an important basis for the future design of in situ bioremediation systems for heavy metal-contaminated sites.

Isolation of Bacteria From Seahorse (Hippocampus barbouri)

Captive breeding of seahorses (Hippocampus barbouri) which is a follow-up of their activities in the exploitation of natural large - scale does not escape from the problems of the disease. Gills and kidneys are the main target of the inspection. Wet mount is one way of checking the disease. This study aims to look at other forms of bacteria isolated from the gills and kidney seahorse (H. barbouri) morphologically. Media used are media Zobell Marine Agar (ZMA) and Thiosulphate Citrate Bile Salts Sucrose Agar (TCBSA) then be isolated bacteria with a pillowcase technique spread to see koloi dominant bacteria. more dominant bacteria grow dimurinikan back with scratch method (streak). The result of five isolates (isolates A, B, C, D and E) were predominantly found growing on media ZMA, two isolates (isolates B and C) not found growing on media TCBSA. Overall bacteria in media and TCBSA ZMA has the form round colonies and smooth-edged. TCBSA media can not be found on the bacterial colonies that fluoresce.

Date Palm (Phoenix dactylifera L.) Flour as an Alternative Culture Media for the Growth of Escherichia coli and Bacillus cereus

The high cost of bacterial growth culture media can result in obstacles in the process of practicum or research in the field of microbiology. Date palm (Phoenix dactylifera L.) is the oldest fruit plant that grows in the Arabian Peninsula, North Africa and the Middle East. Dates are a source of high energy food with sugar content of 72% - 88%. This research was conducted to test the ability of date palm flour to grow Escherichia coli and Bacillus cereus bacteria as an alternative medium to replace NA media. In this study using total number of bacteria/ TPC (Total Plate Count) method to calculated the number of colonies of bacteria. The results of this study the number of colonies of Escherichia coli bacteria was more than the number of colonies of Bacillus cereus, that is 54 x 105CFU/g on concentration media 8 gr. When compared with NA media, date palm flour media can be used as an inexpensive alternative culture medium for bacteria.

Microbial exploration from two different ecosystems in Central Sulawesi, Indonesia

Abstract. Ratnawati, Sudewi S, Jaya K, Saleh AR. 2022. Microbial exploration from two different ecosystems in Central Sulawesi, Indonesia. Biodiversitas 23: 6191-6198. A supportive growing environment and the presence of microbes in the soil are considered good habitats for plant growth. Endophytic microbes live in symbiosis (mutual benefit) with their host plants, both in the stem and root tissues of plants, providing defense services in biotic and abiotic stress situations. This study was aimed to identify various microbes that exist in various agricultural cultivation ecosystems in Central Sulawesi. Microbial sampling was obtained from healthy plant tissues (endophytes) and rhizosphere in lowland rice and shallot plantation ecosystems. The sample obtained was then weighed as much as 5 g and surface sterilized for further isolation by serial dilution method to be spread on NA (Nutrient Agar) media for bacteria, and PDA (Potato Dextrose Agar) for fungi. The microbes that had grown were re-isolated to obtain pure isolate culture of microbes. The results showed that 8 isolates from the rhizosphere and 4 isolates as endophytes in the ecosystem of organic rice fields were recorded. The fungal isolates from the shallot plantation “Lembah Palu” found as many as 12 isolates from rhizosphere and 4 isolates as endophytes. The results of macroscopic and microscopic characteristics on fungal isolates identified as the species of Trichoderma, Fusarium, Penicillium, Gliocladium and Aspergillus.

Disparate Regions of the Human Chemokine CXCL10 Exhibit Broad-Spectrum Antimicrobial Activity against Biodefense and Antibiotic-Resistant Bacterial Pathogens.

CXCL10 is a pro-inflammatory chemokine produced by the host in response to microbial infection. In addition to canonical, receptor-dependent actions affecting immune-cell migration and activation, CXCL10 has also been found to directly kill a broad range of pathogenic bacteria. Prior investigations suggest that the bactericidal effects of CXCL10 occur through two distinct pathways that compromise the cell envelope. These observations raise the intriguing notion that CXCL10 features a separable pair of antimicrobial domains. Herein, we affirm this possibility through peptide-based mapping and structure/function analyses, which demonstrate that discrete peptides derived from the N- and C-terminal regions of CXCL10 mediate bacterial killing. The N-terminal derivative, peptide P1, exhibited marked antimicrobial activity against Bacillus anthracis vegetative bacilli and spores, as well as antibiotic-resistant clinical isolates of Klebsiella pneumoniae, Acinetobacter baumannii, Enterococcus faecium, and Staphylococcus aureus, among others. At bactericidal concentrations, peptide P1 had a minimal degree of chemotactic activity, but did not cause red blood cell hemolysis or cytotoxic effects against primary human cells. The C-terminal derivative, peptide P9, exhibited antimicrobial effects, but only against Gram-negative bacteria in low-salt medium─conditions under which the peptide can adopt an α-helical conformation. The introduction of a hydrocarbon staple induced and stabilized α-helicity; accordingly, stapled peptide P9 displayed significantly improved bactericidal effects against both Gram-positive and Gram-negative bacteria in media containing physiologic levels of salt. Together, our findings identify and characterize the antimicrobial regions of CXCL10 and functionalize these novel determinants as discrete peptides with potential therapeutic utility against difficult-to-treat pathogens.

Study on the use of bovine blood protein hydrolysate as a peptone in microbial culture media

Livestock blood is a protein-rich waste byproduct produced during meat production processes in slaughterhouses. Its utilization through conversion into value-added products is an intriguing management strategy. In this study, bovine blood was used to obtain the protein hydrolysate for use as a peptone for microbial growth medium. Lyophilized bovine blood was heat treated to make it susceptible to enzymic hydrolysis, and then enzymatically treated with trypsin (bovine pancreas protease) to produce protein hydrolysate. Physico-chemical features were determined for protein hydrolysate and compared to commercial Merck peptone from meat. Amino acid compositions of bovine blood and commercial peptones were subjected to multivariate analysis based on Euclidean similarity matrix using software PAST. Strains of Staphylococcus aureus 25,923, Pseudomonas aeruginosa 27,853, Staphylococcus aureus 6538 P, Enterococcus faecalis 11,700, Escherichia coli 8739, Klebsiella pneumoniae 13,883, Salmonella typhimurium 14,028 and Listeria monocytogenes 13,932 were used as test microbial strains. Growth of bacteria in culture media based on the peptone from bovine protein hydrolysate was compared to that in corresponding reference media based on commercial peptone. The results of these growth tests were comparable. Growth data were depicted and statistically analyzed using R packages ggplot2 and growthcurver, respectively, providing data fitting a standard form of logistic equation.

Mineralogy of Bioprecipitate Evolution over Induction Times Mediated by Halophilic Bacteria under Various Mg/Ca Molar Ratios

In microbial mineralization experiments, the induction time of mineral precipitation is ambiguous, and this may lead to difficulties in reproducing and confirming the test results. To explore the link between induction time and microbially mediated carbonate precipitation, we report here the mineralogy and morphology of carbonate precipitates induced by the halophilic Halomonas utahensis WMS2 bacterium in media with various Mg/Ca molar ratios over a range of induction times. The results show that the biominerals are formed in an alkaline environment affected by ammonia secreted by H. utahensis WMS2 bacteria. The content of dissolved inorganic carbon increased as a result of carbonic anhydrase catalyzing the hydration of carbon dioxide to release bicarbonate and carbonate ions. The X-ray diffraction (XRD) results show that the phase of mineral precipitated gradually changes from an unstable Mg-rich calcite to metastable monohydrocalcite and then to stable hydromagnesite with an increase in the Mg2+ ion concentration and induction time. The scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) results show that minerals mostly change from single particles/crystallites to aggregations under the action of the microorganisms at different Mg2+ ion concentrations and induction times. Our experiments demonstrate that the carbonate minerals produced in the presence of microbes change significantly with the induction time, in addition to the influence of the hydrochemical factors; this indicates that the induction time is significant in determining the mineralogy of biominerals.

Bioprocess of Oil Contaminated Water At Gathering Station Through A Consortium Of Endogenous and Exogenous Bacteria

Production activities of petroleum have resulted in extensive environmental pollution, due to accidents, leaks, and oil spills during these activities. Gathering Station is one production facility at the oil field that serves as a gathering place for several liquids produced from production wells to measure the production flow rate. Wastewater at the Gathering Station that still contains oil, so before being discharged into water bodies should be treated to match the existing quality standards. One of the promising methods to remove the oil-polluted at gathering stations is the use of bioprocess technology, which is an eco-friendly, cost-effective, and sustainable approach. A laboratory study was carried out on the Bioprocess of wastewater contaminated oil at the gathering through a consortium of endogenous bacteria and Bacillus cereus and Pseudomonas aeruginosa as consortium exogenous bacteria. The major objective of this research is to determine the effectiveness of consortium endogenous bacteria and consortium exogenous bacteria (Bacillus cereus and Pseudomonas aeruginosa) in degrading oil at the gathering station. Bioprocess was done by using 10% (v/v) inoculum consortium of endogenous bacteria and 10% (v/v) inoculum Bacillus cereus and Pseudomonas aeruginosa as exogenous bacteria and using oil spill dispersant (OSD) 0.2% (v/v) in media. Oil concentrations were determined by the gravimetric method (SNI 6989.10-2011). The result showed that the mixture of Bacillus cereus and Pseudomonas aeruginosa as exogenous bacteria and consortium endogenous bacteria in media produced the highest value of efficiency in degradation oil that up to 64.29% during 21 days (from 1062 mg/l to 379.25 mg/l), with a total population 65 x 106 cfu/ml, this indicated a synergistic relationship between Bacillus cereus and Pseudomonas aeruginosa as exogenous bacteria and consortium endogenous bacteria at room temperature (21±1°C), pH range value 8.34-9.68 and Total Dissolved Solids (TDS) range value from 553-167 mg/l.

Construction of in vitro fermentation model using gut microbiota relating to glucose and lipid metabolism: a supplementary method for initial screening of polysaccharides with hypoglycemic potentials.

Besides in vitro fecal fermentation model, a few supplementary methods have been constructed for high-throughput screening of polysaccharides with hypoglycemic potentials. The purpose of this study was to establish a co-culture fermentation model constructed by gut microbiota relating to glucose and lipid metabolism as a supplementary method for comparatively evaluating the proliferative effects and hypoglycemic potentials of typical plant polysaccharides, e.g. konjac glucomannan, Lycium barbarum L. polysaccharide, oat glucan and alga-derived fucoidan. The results showed that the mixing culture medium of butyrate-producing bacteria, Bacteroides, Bifidobacterium and Lactobacillus at a ratio of 50:40:9:1 was optimal. This testing model in line with quantitative polymerase chain reaction (qPCR) and metabolite analysis multi-dimensionally differentiated four polysaccharides possessing different behaviors on proliferation of total bacteria and specific genus or strain and accumulation of short chain fatty acids. Our study provided crucial data for establishing an initial screening method for proliferative effect/specific structure-oriented extraction of polysaccharide with hypoglycemic potential. © 2022 Society of Chemical Industry.