Beneficial Lactic Acid Bacteria Research Articles

Traditional Bulgarian Fermented Foods as a Source of Beneficial Lactic Acid Bacteria.

Traditional Bulgarian fermented foods are prominent for their uniqueness of local ingredients, production methods, and endemic microbial species. The present research investigated the diversity and beneficial biological potential of lactic acid bacteria (LAB) isolated from various types of unique Bulgarian fermented foods. Species identification was performed via 16S rDNA sequencing. Biological activity was evaluated by determining antibacterial activity (via agar well diffusion assay), H2O2 production, spectrophotometrically determined auto- and co-aggregation, microbial adhesion to hydrocarbon, and biofilm formation. The biosafety of the isolated lactic acid bacteria was established based on hemolytic activity and phenotypic and genotypic antibiotic susceptibility. Forty-five strains were isolated from fermented foods (sauerkraut, fermented green tomatoes, fermented cucumbers, kefir, white cheese, and Izvara (curdled milk)). Five species were detected: Lactiplantibacillus plantarum, Levilactobacillus koreensis, Levilactobacillus brevis, Lactobacillus helveticus, and Levilactobacillus yonginensis. The most prominent species was L. plantarum, at 47%. For the first time, L. koreensis and L. yonginensis, isolated from unique Bulgarian fermented foods, are reported in this study. The antibacterial effect of the cell-free supernatants was evaluated. An antagonistic effect was observed against Escherichia coli (57%) and Salmonella enterica subsp. enterica serotype Enteritidis (19%) for several L. plantarum strains. Only one L. brevis (Sauerkraut, S15) strain showed activity against E. coli. The best autoaggregation ability at hour 4 was observed for L. koreensis (fermented cucumbers, FC4) (48%) and L. brevis S2 (44%). The highest percentage of co-aggregation with Candida albicans, at hou 4 in the experiments, was observed for strains L. koreensis (fermented green tomato, FGT1) (70%), L. plantarum strains S2 (54%), S13 (51%), and S6 (50%), while at hour 24 for strains L. koreensis FGT1 (95%), L. brevis (Kefir, K7) (89%), L. plantarum S2 (72%), and L. koreensis FC2 (70%). Seven of the isolated LAB strains showed hydrophobicity above 40%. Our results showed that the ability of biofilm formation is strain-dependent. No hemolytic activity was detected. The antibiotic resistance to 10 antibiotics from different groups was tested phenotypically and genotypically. No amplification products were observed in any strains, confirming that the isolates did not carry antibiotic-resistance genes. Traditional fermented Bulgarian foods can be considered functional foods and beneficial LAB sources.

Effects of the diet enrichment with β-glucan, sodium salt of butyric acid and vitamins on growth parameters and the profile of the gut microbiome of juvenile African catfish (Clarias gariepinus)

This study assessed the effect of the addition of active substances, i.e., β-glucan, sodium butyrate and vitamins (C, A, D3, E, K) to the diet of juvenile African catfish (Clarias gariepinus) on growth parameters and the intestinal microbiome. For this purpose, a four-week rearing of juveniles African catfish in a recirculating aquaculture system (RAS) under controlled conditions at 25°C was conducted. The fish were fed commercial feed (control group - C), which was enriched with various levels of sodium butyrate and β-glucan (FQV1 – FQV4). After the experiment, growth parameters such as weight gain (WG; g), length gain (LG; cm), specific growth rate (SGR; % d−1), condition factor (K) survival rate (SR; %) and cannibalism factor (CF; %) were determined. The profile of the intestinal microbiome was also determined using Next-Generation Sequencing (NGS) based on the analysis of the 16 S rRNA subunit. The obtained results indicated that feed supplementation with active substances in appropriate doses had a positive effect on the growth parameters of tested fish. Compared to the control group, statistically significant differences were obtained in WG (C - 7.62 g; FQV3 - FQV1 respectively 12.2–16.65 g), in WL (C - 6.23 cm; FQV3 - FQV1 respectively 7.59–8.74 cm), in SGR (C - 4.7%/d; FQV3 – V1 respectively 12.20 – 16.65 g), in K (C – 0.76; V3 – FQV4 respectively 0.80 – 0.84) (P <0.05). In addition, the control group had the highest value of CF (8.0%) compared to the research groups (P <0.05). The values of α-diversity metrics did not show statistically significant differences. However, the number of unique amplicon sequence variants (ASVs) in research groups confirmed that enriching the diet with the active substances increases the biodiversity of intestinal microbiome (C - 203; FQV4 - 373). In research groups and the control group, Firmicutes and Proteobacteria dominated, additionally, an increased number of beneficial lactic acid bacteria (LAB) of the Lactococcus and Bacillus genus was observed, while the number of potentially pathogenic bacteria of the Candidatus genus was reduced (P <0.05). Principal coordinate analysis (PCoA) determining β-diversity showed that the FQV3 was characterized by varied species composition compared to the other groups. The obtained results showed that a carefully selected composition of active ingredients used in the diet of juvenile African catfish has a beneficial effect on the profile and biodiversity of the intestinal microbiome, which indirectly improves resistance to infections and increases breeding indicators.

The impact of faecal diversion on the gut microbiome: a systematic review

Abstract Diversion of the faecal stream is associated with diversion colitis (DC). Preliminary studies indicate that microbiome dysbiosis contributes to its development and potentially treatment. This review aims to characterise these changes in the context of faecal diversion and identify their clinical impact. A systematic search was conducted using MEDLINE, EMBASE and CENTRAL databases using a predefined search strategy identifying studies investigating changes in microbiome following diversion. Findings reported according to PRISMA guidelines. Of 743 results, 6 met inclusion criteria. Five reported significantly decreased microbiome diversity in the diverted colon. At phylum level, decreases in Bacillota with a concomitant increase in Pseudomonadota were observed, consistent with dysbiosis. At genus level, studies reported decreases in beneficial lactic acid bacteria which produce short-chain fatty acid (SCFA), which inversely correlated with disease severity. Significant losses in commensals were also noted. These changes were seen to be partially reversible with restoration of bowel continuity. Changes within the microbiome were reflected by histopathological findings suggestive of intestinal dysfunction. Faecal diversion is associated with dysbiosis in the diverted colon which may have clinical implications. This is reflected in loss of microbiome diversity, increases in potentially pathogenic-associated phyla and reduction in SCFA-producing and commensal bacteria.

Complete genome sequences of Lactococcus lactis D1_2, a bacterium with antimicrobial properties isolated from peat soil.

Lactococcus lactis is a beneficial lactic acid bacterium commonly studied for its probiotic properties and role in dairy production. Here, we present a complete genome of Lactococcus lactis D1_2, isolated from peat swamp forests. To discover the potential antimicrobial properties, the complete genome of the strain was sequenced and analyzed.

Identification of novel lactic acid bacteria with enhanced protective effects against influenza virus.

Lactic acid bacteria (LAB) exert health-beneficial effects by regulating innate immunity in the intestinal tract. Due to growing health awareness, the demand for LAB and studies have focused on identifying beneficial LAB strains is increasing, especially those that stimulate innate immunity. In this study, the LAB strain D279 (NITE_BP-03645, Latilactobacillus sakei) was isolated from among 741 LAB strains that were analyzed for their ability to induce interleukin 12 (IL-12) production and was subsequently characterized. D279 induced the highest expression of IL-12 among the screened LABs. Furthermore, D279 significantly activated antiviral genes and preferentially induced interferon (IFN)λ expression in vitro, which plays a critical role in the epithelial tissue, thereby conferring strong anti-influenza potency without inflammation. However, it decreased the IFNα levels. The administration of pasteurized D279 to mice resulted in strong anti-influenza potency, with higher natural killer (NK) cell activity and a lower viral load in the lung than in the control. Importantly, none of the D279-administered mice were sacrificed during the viral infection tests. These results suggest that D279 administration confers beneficial effects by regulating innate immunity and that it may be relevant for commercial use in the future.

Application of Bibliometric Visualization and Mind Mapping for Dadih Development

Beneficial lactic acid bacteria (LAB) are used to produce dadih, contributing to its health benefits. Dadih is fermented with lactic acid bacteria that convert lactose into glucose and galactose, enhancing digestibility. Despite its potential, dadih has limited appeal due to its traditional production methods and restricted market availability. To address this issue, the article suggests employing methodical concept development techniques, such as Mind Mapping, to generate innovative ideas for dadih product development. In addition, bibliometric analysis is used to obtain insight into the research trends and prospects in the field of food technology as they pertain to local fermented dadih products. The findings from the VOSviewer analysis reveal various aspects of dadih research, including mutagenicity, food safety, and fermented dairy products. Using these insights and mind-mapping techniques, this study advances dadih product development knowledge and is a foundation for future research.&#x0D;

ANTIPATHOGENIC ACTION AND ANTIBIOTIC SENSITIVITY PATTERN OF THE “BORHANI”-ASSOCIATED LACTIC ACID BACTERIUM WEISSELLA CONFUSA LAB-11

Assessment of the beneficial and safety properties of food-associated microbes is inevitable since they engage in direct interactions with their host via the digestive system. In this view, we have studied the pathogen inhibitory activity and antibiotic susceptibility pattern of a newly isolated lactic acid bacterium obtained from the traditional beneficial beverage borhani. 16S rRNA gene based taxonomic and phylogenetic analysis combined with sugar fermentation tests identified the isolate as Weissella confusa; strain LAB-11. Antimicrobial activity of the lactic acid bacterium was examined using its culture supernatant against ten bacterial pathogens by agar diffusion technique. The isolate inhibited species of Acinetobacter, Bacillus, Escherichia, Klebsiella, Pseudomonas, Salmonella, Shigella and Staphylococcus which indicated a broad spectrum of its antimicrobial activity. Further investigation by coincubation assay revealed a prolonged effect of the antibacterial activity against the above pathogens. The inhibitory activity was found highly effective on the fungal pathogen Candida albicans as well. Antibiotic susceptibility assay revealed that the isolate was sensitive to most of the tested antibiotics while resistant against four antibiotics including ciprofloxacin, cloxacillin, ofloxacin, and vancomycin that might be ascribed to intrinsic resistance. The ability to inhibit a wide range of pathogens while itself being relatively safe concerning the transfer of antibiotic resistance suggests that dairy beverages like borhani which carry such beneficial lactic acid bacteria can be of particular benefits to the consumers exerting preventive effects on associated diseases.

Yeast-extracted nucleotides and nucleic acids as promising feed additives for European sea bass (Dicentrarchus labrax) juveniles

Nowadays functional ingredients have a significant potential for improving current low fish meal (FM) aquafeed formulation in sustaining growth and enhancing animal robustness for Mediterranean aquaculture. Among them, nucleotides (NT) and nucleic acids (NA) drew attention for their application in the last two decades. NT are organic molecules involved in many life-supporting pathways, and are the building blocks of NA, which stand as genetic repositories. NT are naturally present in organic ingredients, and among them FM is known to be one of the highest NT sources. When this NT source is seriously limited, fish might be under the minimum NT requirements, especially in fast growing life stages of carnivorous species. Hence, a trial on European sea bass juveniles was carried out, testing two dietary FM levels (FM10, FM20 as 10% and 20% FM, respectively) supplemented with 500 mg kg-1 yeast-originate NT or NA dose over 80 days. Thereafter, fish were exposed to one week of sub-optimal thermal and dissolved oxygen condition (30°C and 4.0 mg/L O2) to further explore the effect of NT and NA inclusion on immune response and gut microbiome alteration. At the end of the growth period NT increased feed intake at both FM dietary levels. FM20 combined with NA and NT further improved growth performance, enhancing lipid efficiency and increased anti-inflammatory TGF-β. After sub-optimal environmental conditions both NT and NA exerted prebiotic functions on gut microbiome by promoting beneficial lactic acid bacteria such as Weissella and Leuconostoc. At the same time NT in 10% FM diet increased the abundance of Bacillus taxon. In conclusion, the combination of NT/NA included at 500 mg kg-1 was able to promote growth when included in 20% FM level, assuming higher nutritional NT requirement when combined with 10% FM. On the other hand, NT/NA added in 10% FM upregulate proinflammatory IL-1β and favor beneficial gut bacterial taxa.

Draft Genome Sequence of a Putative Raw Milk-Associated Probiotic Bacterium, Pediococcus acidilactici ISO17.

Pediococcus acidilactici is a beneficial lactic acid bacterium frequently studied for its probiotic potential. Here, we present a 2.32-Mb draft genome sequence of strain ISO17, with a G+C content of 42%. The genome was predicted to harbor 4 rRNA genes, 47 tRNA genes, and 2,297 protein-coding sequences.

Probiotic Properties, Safety Assessment, and Aroma-Generating Attributes of Some Lactic Acid Bacteria Isolated from Iranian Traditional Cheese

Artisanal cheeses are known as the source of beneficial lactic acid bacteria (LAB). Therefore, this study aimed to isolate and characterize LAB with different proteolytic activities from Iranian artisanal white cheeses. The isolates were classified into low, medium, and high proteolytic activity clusters via K-means clustering and identified as Lactiplantibacillus (Lpb.) pentosus L11, Lpb. plantarum L33, and Enterococcus faecium L13, respectively. Some safety tests (such as resistance to antibiotics, hemolytic activity, and biogenic amine production), probiotic properties (including cell surface hydrophobicity, auto/co-aggregation, and antibacterial activity), and production of volatile compounds were evaluated. These were non-hemolytic and non-biogenic amine producers, and showed no irregular antibiotic resistance. Lpb. plantarum L33 had the highest hydrophobicity (30.55%) and auto-aggregation (49.56%), and the highest co-aggregation was observed for Lpb. pentosus L11 with Staphylococcus aureus (61.51%). The isolates also showed a remarkable antibacterial effect against pathogenic bacteria. Moreover, Lpb. pentosus L11 and Lpb. plantarum L33 with low and medium proteolytic activity produced a wider range of volatile compounds in milk compared to the strain with a high proteolytic effect. The results showed that a probiotic strain with low or medium proteolytic activity could improve the flavor characteristics of fermented milk.

Corn distiller’s dried grains with solubles as a target for fermentation to improve bioactive functionality for animal feed and as a source for a novel microorganism with antibacterial activity

Plant-based bioenergy by-products such as corn distillers’ dried grains with solubles (DDGS) are widely utilized as animal feed sources and feed ingredients due to their balanced nutritional profile and animal health protective functional qualities. Bioprocessing of this bioenergy by-product using beneficial lactic acid bacteria (LAB)-based fermentation strategy to improve animal-health targeted functional qualities has wider relevance for animal feed applications. In this study, liquid extracts of corn DDGS were fermented with Lactiplantibacillus plantarum and Lactobacillus helveticus. The unfermented and fermented extracts were then analyzed (at 0, 24, 48 and 72-h) for their total soluble phenolic content (TSP), phenolic profile, antioxidant activity via ABTS and DPPH radical scavenging activity, and antimicrobial activity against the gut pathogen Helicobacter pylori using in vitro assay models. Statistical differences in antioxidant activity and phenolic content were observed among the unfermented and fermented extracts. The major phenolic compounds detected in corn DDGS were gallic, dihydroxybenzoic, p-coumaric, caffeic and ferulic acid, and catechin. Antimicrobial activity against H. pylori was observed for the unfermented extracts and the antimicrobial activity was attributed to the growth of a corn DDGS-endemic culture. The culture was isolated, sequenced, and identified as Bacillus amyloliquefaciens. Results of this study indicated that processing strategies of by-products such as LAB- based fermentation of corn DDGS could affect its bioactive-linked functional qualities due to microbial interaction with the phytochemicals. Furthermore, plant by-products can serve as novel sources of beneficial microflora that have relevance in wider agriculture, food safety, and therapeutic applications.

Low-cost culture media designed for biomass production of beneficial lactic acid bacteria for their inclusion in a formula to treat bovine reproductive infections.

As a first step for the use of probiotics in a formula for cattle, it is required to have available low-cost culture medium(s) and efficient production conditions for the growth of probiotic bacteria and high production of cell biomass. De Man-Rogosa-Sharpe (MRS) medium, used frequently for Lactic acid bacteria (LAB) contains adequate ingredients for their growth, but is very expensive for industrial application. The nutrients required for LAB growth are strain-dependent. In this work, traditional culture media were evaluated omitting and/or modifying ingredients in their composition, as carbon or nitrogen source, on the basis of their low-cost industrial waste, to select those supporting the most efficient growth. The results showed that the formulation of culture media containing fructose (0.5%) and molasses (1.0%) was better for the growth and production of cell biomass for all the strains assayed, except Lactobacillus gasseri CRL1421 growing in 1.5% corn syrup. FM902 yeast extract at concentrations between 1.5%-2.5% was the most adequate for most of the strains. The LAB grown in the designed media maintained the beneficial properties for which they selected. The use of the culture media designed to produce biomass decrease production costs, which is an important step for the feasible industrial production of probiotic pharmaceuticals.

Protective effect of crop by-products on Lactobacillus gasseri H87 during freeze-drying and storage

Appropriate cryoprotectants are critical components of effective probiotic preparations. Beneficial lactic acid bacteria can prevent or treat genitourinary tract infections. Here, we aimed to determine a suitable cryoprotectant combined with crop by-products to ensure the viability and pathogen suppression activity of Lactobacillus gasseri H87 for vaginal capsules that can help maintain the balance of vaginal microecology. Among the five selected cryoprotectants, 15% skim milk (SM) makes L. gasseri H87 survival rate of reaches 56.5%, effectively guaranteeing maximum bacteriocin production by minimizing bacterial cell damage. On the basis of 15% SM, further addition of 1% pomegranate peel extract (PPE) optimized the production of bacteriocin, resulting in the best bacteriostatic effect. After six months of lyophilized storage, L. gasseri H87 from vaginal capsules preserved with 15% SM + 1% PPE had an inhibitory zone of 16.45 mm against the indicator strain Lactobacillus iners. Both lyophilization and storage reduced the adhesion of L. gasseri H87, but the first subculture after 6 months fully restored adhesion under all conditions. These results suggest that skim milk combined with PPE can serve as a suitable cryoprotectant. Lyophilized L. gasseri H87 vaginal capsules have the potential for use in the pharmaceutical industry.

Inhibition of Pathogenic Microbes by the Lactic Acid Bacteria Limosilactobacillus Fermentum Strain LAB-1 and Levilactobacillus Brevis Strain LAB-5 Isolated from the Dairy Beverage Borhani

Lactic acid bacteria (LAB) with prominent antimicrobial effects against pathogens have been reported in several milk-based and plant-based foods. Borhani is a popular beverage prepared from the ingredients of both dairy and plant origins and is believed to be highly beneficial for health. Herein, we report the pathogen-inhibitory activity of two borhani-associated lactic acid bacteria (LAB), Limosilactobacillus fermentum strain LAB-1 and Levilactobacillus brevis strain LAB-5. Their antimicrobial activity was primarily assessed using the cell free supernatant (CFS) by agar diffusion technique in which both strains showed strong antimicrobial effects against several pathogenic and spoilage microorganisms including Acinetobacter baumannii, Bacillus cereus, Bacillus subtilis, Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa, Salmonella abony, Salmonella typhi, Shigella flexneri, and Staphylococcus aureus. The L. fermentum strain with its ability to inhibit all the target pathogens appeared to be more effective with larger inhibition-zone formation as compared to the L. brevis strain which also successfully inhibited all pathogens but had relatively little effects on A. baumannii. The extent of their inhibitory effect was further assessed by co-culture inhibition assay in which growth of the test microbes was monitored for 24 hours in presence of the CFS. The CFS of both lactic acid bacteria could effectively inhibit growth of the pathogenic microbes for a significant period of time. While the L. fermentum strain could almost completely stop growth of all test organisms, the L. brevis strain was particularly effective against Shigella flexneri and the Salmonella species. Our study, therefore, suggests the presence of beneficial lactic acid bacteria in borhani which can be of important use as antimicrobial agents in functional foods and therapeutics to help acquire protection against drug resistant pathogens.

Molecular Identification of Lactic Acid Bacteria Isolated from Fermented Rice

Background: Fermented rice is known to possess probiotic capability. Probiotics are live microorganisms that confers consumer with enormous health benefits. This research was determined on isolation and molecularly identifies beneficial lactic acid bacteria from fermented rice water. Methods: Locally cultivated Osuemegbe Rice grains were steeped and fermented to isolate lactic acid bacteria strains. De Man Rogosa Sharpe (MRS) media was used for the isolation of lactic acid bacteria. The fermented rice water was serially diluted, plated and incubated at 37 °C for 48 hours under anaerobic conditions. Single colonies were subjected to biochemical analysis and gram-staining. Subsequently, 16s rRNA Identification of bacterial isolates was conducted. Results: The strains of LAB isolated were lactiplantibacillus plantarum CIP 103151and Limosilactobacillus fermentum CIP 102980 which are both beneficial and highly recommended as alternatives to antibiotics since their various mechanisms of growth inhibition against pathogenic bacteria have been extensively documented. Conclusion: The findings in this study confirmed rice to possess strains of probiotic Lactic acid bacteria (LAB) which can be exploited to achieving quality advancement in one health: integrated and unify approach aim at sustainably balance and optimize the health of people, animals, and ecosystem.

Genus and species-specific PCR revealed the presence of beneficial lactic acid bacteria in traditional Bangladeshi fermented milk products Dahi

Genus and species-specific PCR revealed the presence of beneficial lactic acid bacteria in traditional Bangladeshi fermented milk products Dahi

Dietary Supplementation of a Commercial Prebiotic, Probiotic and Their Combination Affected Growth Performance and Transient Intestinal Microbiota of Red Drum (Sciaenops ocellatus L.).

In the present study, the potential synergism between beneficial lactic acid bacteria (Pediococcus acidilactici) contained in a probiotic and a mixture of fermentable complex carbohydrates and autolyzed brewer's yeast (or prebiotic) were explored in red drum. Four experimental diets were formulated from practical ingredients, and the basal diet was supplemented with either probiotic, prebiotic, or both supplements. Red drum juveniles (~5.5 g) were offered the four experimental diets for 56 days, and at the end of the feeding trial fish fed diets supplemented with probiotic had significantly better weight gain than those fed the non-supplemented diets, and higher protein content in their whole-body composition. Transient intestinal microbiome alpha and beta diversity were significantly affected by the dietary treatments. Interestingly, a higher relative abundance of the lactic acid genus Pediococcus was observed for fish fed diets supplemented with the prebiotic. A higher relative abundance was also observed for the predicted functions of the microbial metagenome, and many of these pathways involved the biosynthesis of essential amino acids, vitamins, and nucleotides. Even though no potential synergistic effect was observed, the individual inclusion of these prebiotic and probiotic supplements positively affected the intestinal health and growth performance of red drum, respectively.

Growth, carcass, digestive enzymes, intestinal microbiota and economics in growing Egyptian geese as affected by dietary fiber and fat levels

The present study aimed to investigate the effect of dietary crude fiber and fat levels on growth, carcass, digestive enzymes, intestinal microbiota and economics in growing Egyptian geese. A total number of 150 Egyptian goslings, 4 weeks old, with nearly the same body weights were randomly distributed in to six groups in a 3 × 2 factorial arrangement included. Three levels of fiber (8, 10, and 12%) and two levels of fat (5 and 6%) were used. Results showed that the highest (p = 0.029) body weight (BW) value was found in the experimental group fed 8% fiber diet compared to the other groups. The same trend was observed with increasing the dietary fat level from 5 to 6%. The best feed conversion ratio was associated with feeding geese on the lowest fat level (5%) comparing with the highest one (6%). The highest values (p ˂ 0.05 or 0.01) of the cecal length and weight were recorded in birds fed the high-fiber diet (12%) compared to the other levels. Increasing the level of dietary fat positively affected the concentrations of lipase enzymes. Feeding geese on the high-fiber diet (12%) accompanied with the highest (p ˂ 0.01) counts of beneficial lactic acid bacteria and the lowest (p ˂ 0.01) counts of E. coli and Salmonella compared to the other fiber levels. From an economic point of view, the diet contained 12% crude fiber and 5% crude fat was more suitable for the geese kept from 4 to 12 wks of age without any adverse effects on growth performance.

Insights into the Gut Microbial Communities of Broiler Chicken Fed Black Soldier Fly Larvae-Desmodium-Based Meal as a Dietary Protein Source.

The utilization of insect-based diets to improve gastrointestinal function and gut health in poultry is gaining global attention as a promising feed additive. The objective of this study was to determine the optimal inclusion level of the full-fat black soldier fly larvae (BSFL) and Desmodium intortum (DI) in broiler chicken diets and to evaluate their impact on the microbial community in the gut. The bacterial communities were characterized using Oxford nanopore sequencing of the full-length bacterial 16S rRNA gene. Four dietary treatments, T1 (25% DI + 75% BSFL), T2 (50% DI + 50% BSFL), T3 (75% DI + 25% BSFL) and T4 (100% fishmeal + 0% DI + BSFL), were fed to the broiler chickens for a period of 42 days. Out of the 395,034 classified reads analyzed, the most predominant phyla identified across all the four dietary treatments were Firmicutes (94%), Bacteroidetes (3%), and Proteobacteria (2%). The T1 diet showed the highest alpha diversity and richness according to the Chao1 and Shannon indices. Beta diversity assessment revealed a significant influence of diet on the abundance of the microbiome. There was an increase in beneficial lactic acid bacteria with increasing inclusion of BSFL in the diets. Our findings strongly support the inclusion of BSFL into poultry diet as a promising protein source to reshape the gut microbiota for improved gut health, immune response, and food safety.

In Vitro Examination of the Effect of Honey in the Gastrointestinal Tract

ObjectivesHoney has shown beneficial antibacterial properties in wound healing, but little is known about the effects of honey consumption on human gut health. Herein, we investigate the effects of honey gastric digest on the growth of the common food-borne pathogen Enterotoxigenic E. coli (ETEC) and beneficial lactic acid bacteria within the gastric environment and a small intestine microbial community, respectively.Methods In Vitro Gastric Digestion: An in vitro digestion of both honey and a simple sugar control (42% fructose, 35% glucose, 23% water) was performed in a simulated gastric electrolyte solution containing pepsin and hydrochloric acid (HCl). Each solution was adjusted to a pH of 2.5, and placed in an incubating shaker at 37°C, 200rpm for 120 minutes. For ETEC survival experiments, 800,000 CFU/mL of ETEC in brain heart infusion (BHI) broth was added to each solution before pH adjustment. Samples were collected every 20 minutes, plated on BHI, and colonies counted the following morning. In Vitro Fermentation: Digested honey or control was added at 1% w/v to a small intestine microbial mock community, containing 100,000 cells each of 8 common small intestinal commensal bacteria, and fermented anaerobically for 40 hours at 37°C and an initial pH of 5.5. Samples were collected for 16S rRNA analysis; optical density and pH were measured to determine bacterial growth and estimate the relative production of acids in the culture media, respectively. 16S Analysis: For individual CFU, full length amplicons were analyzed by Sanger sequencing and NCBI BLAST. For fermentations, the V4 region was amplified and sequenced on Illumina MiSeq at UC Davis Tech Core. Sequences were analyzed in Qiime 2. Statistical analyses were performed via DESeq2 in R.ResultsOur preliminary data shows that under in vitro gastric digestion conditions, ETEC survival decreased more quickly in honey than a simple sugar control. Total CFU were similar between the two conditions at 120 minutes, but Sanger sequencing identified a majority of colonies plated from the honey condition as genus Bacillus. During in vitro fermentation, differences in the relative abundance of specific taxa between honey and control did not reach statistical significance.ConclusionsOur pilot experiments suggest honey may affect the survival of gastric pathogens within the stomach. Research is ongoing to confirm these results.Funding SourcesThe National Honey Board, USDA, and the Dean's Distinguished Graduate Fellowship, UC Davis.