Culture Fermentation Research Articles

13C-Labelled Glucose Reveals Shifts in Fermentation Pathway During Cathodic Electro-Fermentation with Mixed Microbial Culture.

Cathodic Electro-Fermentation (CEF) is an innovative approach to manage the spectrum of products deriving from anaerobic fermentation. Herein, mixed microbial culture fermentation using a ternary mixture containing labelled 13C glucose and non-labelled acetate and ethanol was studied to identify the role of polarization on the metabolic pathways of glucose fermentation. CEF at an applied potential of -700 mV (vs. SHE, Standard Hydrogen Electrode) enhanced the production yield of acetate, propionate, and butyrate (0.90±0.10, 0.22±0.03, and 0.34±0.05 mol/mol; respectively) compared to control tests performed at open circuit potential (OCP) (0.54±0.09, 0.15±0.04, and 0.20±0.001 mol/mol, respectively). Results indicate that CEF affected the 13C labelled fermented product levels and their fractional 13C enrichments, allowing to establish metabolic pathway models. This work demonstrates that, under cathodic polarization, the abundance of both fully 13C labelled propionate and butyrate isotopomers increased compared to control tests. The effect of CEF is mainly due to intermediates initially produced from the glucose metabolic transformation in the presence of non-labelled acetate and ethanol as external substrates. These findings represent a significant advancement in current knowledge of CEF, which offers a promising tool to control mixed cultures bioprocesses.

Proximate Analysis and Digestibility of Modified Corn Flour

Abstract: The quality of corn flour can improve through a modification process. The modification method that can be done to improve the characteristics of corn flour is through a controlled fermentation process accompanied by pregelatinization. This study aims to determine the effect modification of corn flour by spontaneous fermentation, controlled fermentation using Lactobacillus fabifermentans or Aspergillus sp culture and mixed culture of L. fabifermentans and Aspergillus sp (1:3) followed by pregelatinization at 80ºC for 15 minutes. The treatment variables in this study were spontaneous fermentation, controlled fermentation using single cultures of L. fabifermentans or Aspergillus sp., and mixed cultures of these microbes with a ratio of 1:3. This study consisted of 4 treatments with three groups each. This research is an experimental study using Randomized Block Design (RBD). Observation variables in this study were proximates tests (moisture content, ash, protein, fat, and carbohydrates) and starch digestibility. The data were processed using the SPSS version 22 program, with the method analysis of variance (ANOVA), and continued with Duncan’s Multiple Range Test (DMRT). The results of variance analysis from spontaneous fermentation treatments, single culture fermentation of L. fabifermentans or Aspergillus sp, and mixed cultures of L. fabifermentans and Aspergillus sp (1:3) gave significant effect on moisture content, fat, carbohydrates, and starch digestibility of modified corn flour. The best-modified corn flour was obtained by controlled fermentation treatment using L. fabifermentans followed by pregelatinization with characteristics of moisture content 14.46%, ash 0.13%, protein 7.41%, fat 0.65%, carbohydrates 80.06%, and starch digestibility 87.15%.

PENGARUH LAMA WAKTU FERMENTASI DAUN KELOR (Moringa oleifera) DENGAN BAKTERI ASAM LAKTAT TERHADAP KONSENTRASI ASAM AMINO

Moringa (Moringa oleifera) is a nutrient-densed food that can be used as a food source and possess pharmacological properties. Fermented Moringa has a better amino acid profiles and potentially has a greater digestibility. Nevertheless, the effect of lactic acid bacteria as fermentation culture on Moringa’s amino acid profiles is warrant for investigation. The purpose of this study was to determine the effect of the Moringa’s fermentation with lactic acid bacteria on its nutritional value, especially amino acid. In this study, Moringa leaves were fermented with lactic acid bacteria for 0, 24, and 48 hours. Amino acid concentrations with fermentation 0, 24, and 48 hours respectively were 1007.94 mg/kg, 1304.13 mg/kg, and 521.12 mg/kg, where the highest concentration of amino acids was in Moringa leaves which were fermented for 24 hours. The concentrations of various amino acids in Moringa leaves were measured by High Performance Liquid Chromatography. The best treatment was 24 hours of fermentation, where the total amino acid (TAA) was 1304.13 mg/kg.

Growth and metabolism of halophilic Candida versatilis and Tetragenococcus halophilus in simultaneous and sequential fermentation of salted soy whey

This study investigated various strategies: mono-, simultaneous and sequential fermentation of halophilic Candida versatilis and Tetragenococcus halophilus to valorize salted whey, a side stream of salted tofu (pressed beancurd) production, with an ultimate goal of creating a soy sauce-like condiment. Growth, glucose, organic acids were monitored throughout fermentation, while free amino acids and volatile compounds were analyzed on the final days. In monoculture fermentation, both C. versatilis and T. halophilus thrived in salted soy whey. However, in co-culture fermentation, an antagonistic relationship was observed, wherein C. versatilis growth was slightly suppressed and T. halophilus was significantly inhibited. In C. versatilis-involved fermentations, no significant (p > 0.05) differences in key volatile and non-volatile chemical components were found among various fermentation modes. Key soy sauce-like volatile compounds, such as 4-ethylguaiacol and 4-ethylphenol, were detected in all C. versatilis-fermented salted soy whey, while T. halophilus primarily functioned as a lactic and acetic acids producer. This study highlights the potential of mixed culture fermentation involving soy sauce yeast and lactic acid bacteria for eventually developing a soy sauce-like condiment from salted soy whey, with C. versatilis playing a crucial role in flavour development. The findings suggest that fermenting of a single culture of C. versatilis in lactic acid-adjusted salted soy whey could be a viable and efficient choice for future production of soy sauce-like condiment.

Elevated levels of branched chain fatty acids in low-salt fish sauce by co-fermentation: flavor improvement and metabolism analysis.

Traditional fish sauce products rely on relatively long fermentation time and high salt concentration, resulting in inconsistent quality and health risks. Branched-chain fatty acids (BCFAs) are associated with nutritional benefits and health-care effects, mainly derived from food fermentation. This study aimed to screen BCFAs-producing bacteria with high protease and aminotransferase activity as starter cultures for fish sauce fermentation. The low-salt fish sauce products were obtained by co-fermentation with three chosen strains. Trichloroacetic acid (TCA)-soluble peptides and amino acid nitrogen concentrations were higher in the co-fermentation group (FH group). The organoleptic evaluation showed co-fermentation optimized flavor composition and endured with rich taste. The levels of BCFAs and branched-chain amino acids (BCAAs) significantly increased by co-fermentation. Volatile metabolomics analysis indicated that BCFAs, branched-chain esters, and pyrazines were the key flavor compounds in the co-fermented group. The co-fermentation system with selected strains to ferment low-salt fish sauce has the potential to increase BCFA content and improve flavor and nutrition. © 2024 Society of Chemical Industry.

Bacteriocins from lactic acid bacteria: strategies for the bioprotection of dairy foods

Lactic acid bacteria (LAB), essential in fermenting milk, produce an array of antimicrobial compounds, notably bacteriocins, which contribute to the extended shelf life of dairy goods. Bacteriocins, ribosomally synthesized peptides, display broad or narrow-spectrum antimicrobial activity, thus holding promise in food preservation. The classification of LAB bacteriocins is intricate, reflecting evolving genomic insights and biosynthesis mechanisms. Strategies for integrating bacteriocins into dairy products include purified forms, bacteriocin-producing LAB, and bacteriocin-containing fermentates, each with distinct advantages and considerations. Optimization of fermentation conditions, encompassing time, temperature, pH, and culture medium, is essential for maximizing bacteriocin production. This optimization facilitates enhanced quality and safety of fermented dairy items, aligning with the growing consumer preference for natural, minimally processed foods. Furthermore, the incorporation of bacteriocins into a hurdle approach alongside thermal and non-thermal treatments holds promise for augmenting food bioprotection while reducing reliance on chemical preservatives. This comprehensive overview underscores the potential of LAB bacteriocins as a natural, effective alternative to conventional food preservatives, offering insights into their application and optimization in dairy product preservation.

Agitated and temporary immersion bioreactor cultures of Reynoutria japonica Houtt. as a rich source of phenolic compounds

Reynoutria japonica Houtt. (Japanese knotweed) is an invasive plant belonging to the Polygonaceae family. However, being native to East Asia, it has been used in natural medicine for ages because of its broad range of biological activity. Although R. japonica is known as a rich source of phenolic compounds, plant biomass collected from the field may be contaminated with toxic elements like heavy metals, and the level of metabolite accumulation depends on environmental conditions. Therefore, the aim of this study was to derive Japanese knotweed tissue cultures and investigate biomass production and phenolic compound synthesis in in vitro conditions. Plants were cultivated in a traditional agar-solidified medium, in a liquid medium with rotary shaking (agitated culture), and in a temporary immersion bioreactors Plantform™, as well as in soil (ex vitro conditions). Analyses of the growth index and dry weight accumulation were performed on the collected material. In the extracts obtained from examined plants, qualitative and quantitative analysis of phenolic derivatives using DAD-HPLC was conducted to determine the sum of phenolic compounds, as well as the quantity of selected phenolic acids, catechins, and other flavonoids. Results have shown that agitated cultures and temporary immersion bioreactors increased biomass accumulation compared to solid medium cultures. Tissue cultures of R. japonica had increased synthesis of phenolic compounds compared to plants from ex vitro conditions. Shoots and roots from agitated cultures were 2.8- and 3.3-fold richer in catechins, respectively, compared to plants cultivated in soil. Based on the obtained results it can be concluded that agitated and bioreactor cultures are the best source of Japanese knotweed biomass rich in valuable secondary metabolites.

Inhibiting methanogenesis by targeting thermodynamics and enzymatic reactions in mixed cultures of rumen microbes in vitro.

Mitigation of enteric methane (CH4) emissions from ruminant livestock represents an opportunity to improve the sustainability, productivity, and profitability of beef and dairy production. Ruminal methanogenesis can be mitigated via two primary strategies: (1) alternative electron acceptors and (2) enzymatic inhibition of methanogenic pathways. The former utilizes the thermodynamic favorability of certain reactions such as nitrate/nitrite reduction to ammonia (NH3) while the latter targets specific enzymes using structural analogs of CH4 and methanogenic cofactors such as bromochloromethane (BCM). In this study, we investigated the effects of four additives and their combinations on CH4 production by rumen microbes in batch culture. Sodium nitrate (NaNO3), sodium sulfate (Na2SO4), and 3-nitro-1-propionate (3NPA) were included as thermodynamic inhibitors, whereas BCM was included as a enzymatic inhibitor. Individual additives were evaluated at three levels of inclusion in experiments 1 and 2. Highest level of each additive was used to determine the combined effect of NaNO3 + Na2SO4 (NS), NS + 3NPA (NSP), and NSP + BCM (NSPB) in experiments 3 and 4. Experimental diets were high, medium, and low forage diets (HF, MF, and LF, respectively) and consisted of alfalfa hay and a concentrate mix formulated to obtain the following forage to concentrate ratios: 70:30, 50:50, and 30:70, respectively. Diets with additives were placed in fermentation culture bottles and incubated in a water bath (39°C) for 6, 12, or 24h. Microbial DNA was extracted for 16S rRNA and ITS gene amplicon sequencing. In experiments 1 and 2, CH4 concentrations in control cultures decreased in the order of LF, MF, and HF diets, whereas in experiments 3 and 4, CH4 was highest in MF diet followed by HF and LF diets. Culture pH and NH3 in the control decreased in the order of HF, MF, to LF as expected. NaNO3 decreased (p < 0.001) CH4 and butyrate and increased acetate and propionate (p < 0.03 and 0.003, respectively). Cultures receiving NaNO3 had an enrichment of microorganisms capable of nitrate and nitrite reduction. 3NPA also decreased CH4 at 6h with no further decrease at 24 h (p < 0.001). BCM significantly inhibited methanogenesis regardless of inclusion levels as well as in the presence of the thermodynamic inhibitors (p < 0.001) while enriching succinate producers and assimilators as well as propionate producers (p adj < 0.05). However, individual inclusion of BCM decreased total short chain fatty acid (SCFA) concentrations (p < 0.002). Inhibition of methanogenesis with BCM individually and in combination with the other additives increased gaseous H2 concentrations (p < 0.001 individually and 0.028 in combination) while decreasing acetate to propionate ratio (p < 0.001). Only the cultures treated with BCM in combination with other additives significantly (padj < 0.05) decreased the abundance of Methanobrevibacter expressed as log fold change. Overall, the combination of thermodynamic and enzymatic inhibitors presented a promising effect on ruminal fermentation in-vitro, inhibiting methanogenesis while optimizing the other fermentation parameters such as pH, NH3, and SCFAs. Here, we provide a proof of concept that the combination of an electron acceptor and a methane analog may be exploited to improve microbial efficiency via methanogenesis inhibition.

Effects of Caffeine Doses on Rumen Fermentation Profile and Nutrient Digestibility Using a Lactating Cow Diet under Continuous Cultures Conditions

Caffeine is a plant secondary metabolite, commonly known for its bioactivity properties. This molecule increases microbial activity during anaerobic digestion. The aim of this study was to determine the effects of caffeine doses on the rumen fermentation profile and nutrient digestibility when continuous culture fermenters were fed a lactating cow’s diet. We hypothesize that adding caffeine doses into continuous culture fermenters with a rumen fluid inoculum will not affect anaerobic fermentation or nutrient utilization. Fermenters were fed twice a day (at 0800 and 2000 h) with an experimental diet of high-producing dairy cows (53.55 g/DM day; Forage:Concentrate ratio, F:C of 40:60). Four levels of caffeine (0 ppm, 50 ppm, 100 ppm, and 150 ppm) were added to the diets as a treatment. The experiment was arranged in a randomized complete block design. Two blocks of four fermenters were run in two replicated periods of ten days. Statistical analyses were conducted in SAS version 9.4 for Windows (SAS Institute Inc., Cary, NC) using the GLIMMIX procedure. The addition of caffeine at a 50 ppm dose on continuous culture fermentation decreased the protozoal counts (Diplodinium spp.) (p = 0.03) and ammonia concentrations (p &lt; 0.05). A treatment of 50 ppm of caffeine increased the DM, OM, and starch digestibility (p &lt; 0.05). When caffeine doses increased further than 50 ppm, the OM, DM, and starch digestibility decreased linearly (p = 0.01). The total volatile fatty acids and fatty acid proportions were unaffected. However, the acetate-to-propionate ratio (A:P) tended to decrease linearly among treatments (p = 0.07). The means of pH measurements and maximum pH had a significantly linear decrease effect (p &lt; 0.01). Caffeine may represent a potential rumen fermentation modifier for use in lactating cow diets.

Exploring strain-level diversity in the gut microbiome through mucin particle adhesion.

Metabolism of mucin glycans by gut bacteria represents a crucial strategy for accessing nutrient reservoirs. The efficacy of mucin glycan utilization among gut bacteria hinges on the metabolic capabilities of individual strains, necessitating meticulous strain-level characterization. In this investigation, we used glass beads chemically immobilized with mucins to selectively enrich bacteria from fecal fermentation cultures, based on their superior adhesion to and metabolism of mucin glycoproteins. These findings lend support to the hypothesis that the physical interactions between bacteria and mucin glycoprotein components directly correlate with their capacity to utilize mucins as nutrient sources. Furthermore, our study implies that physical proximity may significantly influence bacterial nutrient acquisition within the ecosystem, facilitating gut bacteria's access to carbohydrate components.

Mixed culture fermentation using Lactobacillus delbrueckii and novel Lactiplantibacillus plantarum strains isolated from traditional chhurpi from Sikkim Himalayan region for potential probiotic and improved functional properties

The aim of the study was to isolate potential probiotic lactic acid bacteria (LAB) strains from the traditional fermented milk products, Chhurpi of the Sikkim Himalayan region and to prepare curd using mixed culture fermentation. A preliminary probiotic assessment of 110 LAB isolates including antimicrobial activity, bile and acid tolerance, surface hydrophobicity, auto-aggregation and co-aggregation, and adhesion to Caco-2 cells, was performed. Lactiplantibacillus plantarum strains N4, CHDE2, CHDE4, and SS22 demonstrated better viability in bile (0.3%) and acid (pH 2.5), adherence with hydrophobicity (13.93–92.85%), auto-aggregation (72.44–89.74%), adhesion to Caco-2 cells (45–73.61%) and antimicrobial activity against food borne pathogens. These strains were used for mixed culture fermentation with a previously screened curd forming strain Lactobacillus delbrueckii WS4. Curd produced using mixed culture fermentation of Lb. delbrueckii WS4 and the selected Lp. plantarum strains had a relatively higher acid production (pH 3.97–4.01), protein hydrolysis, and antioxidant activity. Further, mixed culture fermentation also resulted in the increase of HOCl scavenging activity (12.22–32.96%), myeloperoxidase (MPO) inhibition activity (22.38–42.94%) and angiotensin converting enzyme (ACE) inhibition (15.61–33.03%) as compared to that of WS4 fermentation (P < 0.05). This is the first report on identification of potential probiotic strains from the traditional fermented milk products of Sikkim and application in mixed culture fermentation with enhanced multifunctional potential.

The Diversity of Yeasts in Beekeeping Environments and the Selection of a Culture Starter for the Development of a Mead

The biodiversity of several beekeeping environments and honey samples was studied. The bacterial and yeast counts ranged from 0.00 to 5.19 Log CFU/g and from 0.00 to 3.33 Log CFU/g, respectively, presenting significant differences between the values. Of the honey samples, two of them exceeded the legislative limit established for total aerobic bacteria (5.19 Log CFU/g and 5.03 Log CFU/g). A total of ninety-eight yeast strains were isolated, with eight different species: Candida albicans, Dekkera anomala, Zygosaccharomyces rouxii, Z. mellis, Kazachstania unispora, Meyerozyma guillermondii, Saccharomyces cerevisiae, and S. unisporus. This implies a low microbial biodiversity and a low genetic variability index (D = 0.116 and 6–19%, respectively) due to the large number of genetically identical individuals found in each species. To select the most adequate strains for mead elaboration (with pure and mixed cultures), the fermentation capacity and organoleptic characteristics were studied. The best yeasts were chosen for the “pure culture fermentation” of honey (Saccharomyces spp. M11A2) and for mixed sequential inoculation (K. unispora M17A2). Both of the yeasts were isolated from honey and selected for their high fermentative capacity and resistance to ethanol. The results of the sensory analysis of the meads that were produced, in addition to one commercial product, were compared and indicated that the one inoculated with the pure culture had the best overall impression.

Optimizing the production of dsRNA biocontrols in microbial systems using multiple transcriptional terminators.

Crop pests and pathogens annually cause over $220 billion in global crop damage, with insects consuming 5%-20%of major grain crops. Current crop pest and disease control strategies rely on insecticidal and fungicidal sprays, plant genetic resistance, transgenes, and agricultural practices. Double-stranded RNA(dsRNA) is emerging as a novel sustainable method of plant protection as an alternative to traditional chemical pesticides. Successful commercialization of dsRNA-based biocontrols requires the economical production of large quantities of dsRNA combined with suitable delivery methods to ensure RNAi efficacy against the target pest. In this study, we have optimized the design of plasmid DNA constructs to produce dsRNA biocontrols in Escherichia coli, by employing a wide range of alternative synthetic transcriptional terminators before measurement of dsRNA yield. We demonstrate that a 7.8-fold increase of dsRNA was achieved using triple synthetic transcriptional terminators within a dual T7 dsRNA production system compared to the absence of transcriptional terminators. Moreover, our data demonstratethat batch fermentation production dsRNA using multiple transcriptional terminators is scalable and generates significantly higher yields of dsRNA generated in the absence of transcriptional terminators at both small-scale batch culture and large-scale fermentation. In addition, we show that application of these dsRNA biocontrols expressed in E. coli cells results in increased insect mortality. Finally, novel mass spectrometry analysis was performed to determine the precise sites of transcriptional termination at the different transcriptional terminators providing important further mechanistic insight.

Optimising butyric and lactic acid yield from xylose by adjusting pH

This work studies the pH effect in xylose mixed culture fermentation, focusing on lactic and butyric acid production. Batch tests showed a complete substrate consumption at slightly acidic (pH 6) and alkaline conditions (pH 8), but a great inhibition of xylose conversion was observed at pH 4. Acetic acid was the only product at pH 8, while at pH 6, butyric and propionic acids were quantified as well with a large proportion of unidentified compounds. Continuous reactor operation showed that changes within the acidic pH range (pH 4.5 to pH 6) affect the acidification degree but not the product distribution, reaching the maximum butyric acid yield (0.38 Cmol/Cmol-s) at pH 5, while lactic acid was only detected when xylose conversion or butyric acid concentration dropped. Batch tests demonstrated that butyric acid was not inhibitory for xylose or lactic acid conversion and that the main product of lactic acid fermentation was butyric acid. Although pH is an essential variable steering the fermentation yield and selectivity, this study demonstrates that it must be combined with other operational conditions in order to obtain a stable production of lactic and butyric acids.

Polygonati rhizoma fermentation by Monascus ruber and evaluation of fermentation products in vitro

This study investigated the conditions for polygonati rhizoma (PR) fermentation by Monascus ruber and the lipid-lowering activity of the resulting product. Monascus ruber was used for the solid-state fermentation of PR, and the response surface method was used to optimize the fermentation culture medium parameters. The optimal fermentation system yielded a maximum monacolin K concentration of 21.82 ± 0.34 mg/g. The fermentation conditions were as follows: 12.5 mmol/kg of L-glutamic acid, 0.64 mmol/kg of cyclic adenosine monophosphate, 3.0 wt% of yeast extract powder, a fermentation period of 15 days, and a fermentation temperature of 30 ℃. The binding capacities of unfermented PR, “Nine-Steam-Nine-Bask” processed Polygonati rhizoma (NPR), and Monascus ruber solid-state fermented polygonati rhizoma (MPR) to sodium cholate, sodium taurocholate, and sodium glycolate were determined. MPR showed a stronger bile acid-binding capacity than unfermented PR. In addition, MPR exhibited the highest cholesterol inhibitory capacity of 51.43±1.41 %. Thus, MPR can be used as a potential antilipemic agent with potent hypolipidemic effects.

Comprehensive in vitro and in silico Evaluation of Safety and Probiotic Potential of Lactiplantibacillus plantarum strain LFN10

ABSTRACT The study aimed to assess the safety and probiotic potential of strain Lactiplantibacillus plantarum LFN10, isolated from Algerian fermented milk “Lben,” using genome-sequencing and in vitro approaches. Safety assessments revealed LFN10 as negative for virulence and antibiotic resistance. With favorable physiological and biochemical traits, a versatile carbohydrate metabolism and good exopolysaccharide production abilities, it qualifies as nonstarter culture for food fermentation. The strain displayed resilience to acidic and bile salt stress and exhibited strong cholesterol-lowering capabilities. The moderate interaction with pathogens suggests its potential ability to inhibit them. The strain also demonstrated inhibitory effects on foodborne pathogens. Whole genome sequencing and bioinformatics analyses facilitated taxogenomic classification and confirmed the presence of stable chromosomal marker genes associated with probiotic and technological functional qualities. Overall, LFN10 appears as a promising candidate for application as probiotics, which requires further in vivo studies to confirm its safety and efficacy as well as to optimize its application in food and as nutraceuticals.

Exploring volatile compounds and microbial dynamics: Kluyveromyces marxianus and Hanseniaspora opuntiae reduce Forastero cocoa fermentation time

Traditional cocoa bean fermentation is a spontaneous process and can result in heterogeneous sensory quality. For this reason, yeast-integrated starter cultures may be an option for creating consistent organoleptic profiles. This study proposes the mixture of Hanseniaspora opuntiae and Kluyveromyces marxianus (from non-cocoa fermentation) as starter culture candidates. The microorganisms and volatile compounds were analyzed during the cocoa fermentation process, and the most abundant were correlated with predominant microorganisms. Results showed that Kluyveromyces marxianus, isolated from mezcal fermentation, was identified as the dominant yeast by high-throughput DNA sequencing. A total of 63 volatile compounds identified by HS-SPME-GC–MS were correlated with the more abundant bacteria and yeast using Principal Component Analysis and Agglomerative Hierarchical Clustering. This study demonstrates that yeasts from other fermentative processes can be used as starter cultures in cocoa fermentation and lead to the formation of more aromatic esters, decrease the acetic acid content.

Treatment of dual-flow continuous culture fermenters with an organic essential oil product minimally influenced prokaryotic microbiome

Treatment of dual-flow continuous culture fermenters with an organic essential oil product minimally influenced prokaryotic microbiome

ETHNIC STUDY OF ADUWA KO JAANR, A LESSER-KNOWN FERMENTED GINGER MILD ALCOHOLIC BEVERAGE OF EASTERN HIMALAYAS

Consumption of fermented foods and beverages is a part of the dietary cultures of the Himalayan community and is prevalent amongst various ethnic groups in this region. Native of the Himalayan range ferment food and beverages using 'ethno-microbiological' knowledge acquired and practiced since ages, which lacks documentation. This knowledge is transmitted through practice and verbally to new generations. Women folk are engaged in this traditional fermentation culture with cultural and ethnic significance. In addition to its distinctive tastes, fermented foods and beverages provide health advantages to indigenous people. It becomes essential to highlight their scientific value due to their health benefits and ethnic relevance. The diverse nature of fermented foods and beverages, the fermentation process, and the traditional knowledge behind fermentation are a heritage of the eastern Himalayas. Traditional fermentation, in which raw materials are organic and natural starter culture is used, is part of the people's socio-economic lifestyle. Their preservation highlights organic and conventional practices as an excellent alternative to a healthy lifestyle. The present study documents a lesser-known mild-alcoholic fermented beverage, 'Aduwa ko Jaanr,' from the Eastern Himalayan region. A steady decline in traditional fermentation practices has recently been observed due to changes in food habits and culinary practices.

Optimizing Biogas Production: Comparative Analysis Of Organic Substrates For Enhanced Gas Yield

Study’s Novelty/Excerpt This study uniquely evaluates the biogas optimization potential of various locally sourced substrates, including cow dung, poultry dung, human, and pig manure, through a comparative analysis over a 15-day period using custom-made biodigesters. The research reveals that poultry dung yields the highest gas production, significantly outperforming other substrates with a gas production ratio of 0.20 on day 15, indicating its superior effectiveness. These findings contribute valuable insights into substrate efficiency for biogas production, suggesting poultry dung as a highly effective substrate and proposing co-digestion strategies to further enhance biogas yields. Full Abstract This research aimed to investigate the utilization of various locally sourced substrates in the biogas optimization process and compare the gas yield to determine the most efficient domestic substrate. The samples tested included cow dung, poultry dung, human, and pig manure. A comparative analysis of gas production over a 15-day period was carried out at 3-day intervals using four custom-made biodigesters with batch culture fermentation. The findings revealed that digester 4, utilizing poultry dung, exhibited the highest gas output. The gas production ratios for human, cow, pig, and poultry dung on day 15 were 0.10:0.11:0.12:0.20, equating to percentages of 18.86%, 20.78%, 22.64%, and 37.73% respectively. The notably higher percentage for poultry dung suggests its superior effectiveness as a substrate for biogas production. Alternatively, the co-digestion of cow and/or poultry dung could be considered as a strategy to enhance biogas production.