Mixed Lactic Acid Bacteria Research Articles

Process Optimization and Analysis of Product Quality of Blueberry and Corn Peptide Fermented by Mixed Lactic Acid Bacteria

To study the mixed fermentation technology of blueberry and corn peptide by Lacticaseibacillus rhamnosus ZYN-0417 and Lactiplantibacillus plantarum ZYN-0221 and its effect on fermentation quality, fermentation conditions were optimized using a single-factor test and a Plackett–Burman design combined with a Box–Behnken response surface methodology, with blueberry juice and corn peptide as raw materials and L. rhamnosus ZYN-0417 and Lp. plantarum ZYN-0221 as the starter. The results showed that the optimum fermentation conditions were as follows: the volume ratio of ZYN-0417 and ZYN-0221 was 1:1, the amount of blueberry juice was 20%, the amount of corn peptide was 22%, the amount of glucose was 2%, the amount of inoculation was 5%, the fermentation time was 40 h, and the fermentation temperature was 37 °C. Under optimum conditions, the viable count of lactic acid bacteria in fermented blueberry and corn peptide was 16.28 log CFU/mL, the pH value was 4.86, the total acid content was 14.00 g/L, the total sugar content was 39.98 g/100 g, the protein content was 48.34 g/100 g, the scavenging ability of the DPPH, ABTS+ and ·OH− radicals increased by 10.14%, 10.98% and 25.02%, respectively, the chelating ability of Fe2+ increased by 14.92%, the content of total phenol increased by 1.43 mg/L, the content of total flavonoids increased by 150.87 g/L, the activity of superoxide dismutase increased by 122.10 U/mL, and the activation rate of alcohol dehydrogenase increased by 5.74%. The results showed that mixed lactic acid bacteria could be used as a starter of blueberry and corn peptide and effectively improve the nutritional value of the product.

Effect of fermentation with single and co-culture of lactic acid bacteria on Chinese Elaeagnus angustifolia juice: Evaluation of bioactive compounds and volatile profiles

Chinese Elaeagnus angustifolia (EA) is a homologous food and medicine that is rich in bioactive substances, and most EA is currently treated as an abandoned resource. In this study, various lactic acid bacteria (LAB) were used to ferment EA juice to improve its content of bioactive compounds and the aroma profile to develop a nutritious and acceptable EA beverage. The growth characteristics, total phenolic content, total flavonoid content, antioxidant activity, and aroma profiles of the EA juice after fermentation by pure and mixed LAB were measured. The results of pure LAB fermentation showed that Lactobacillus rhamnosus (BL) had strong adaptability in EA juice, and Lactobacillus fermentium (BF) had the greatest ability to improve its probiotic function. 1-nonanol, 3-buten-1-ol, 3-methyl-, 2-tridecanone, pentanoic acid, and 10-octadecenal could be the typical aroma substances of coculture-fermented EA juice. This is the first study in which EA processing by LAB fermentation has been investigated. The results proved that the fermentation of EA by mixed BL and BF could be a promising method for the high-value utilization of EA.

Optimizing Lactic Acid Bacteria Proportions in Sourdough to Enhance Antifungal Activity and Quality of Partially and Fully Baked Bread.

The organic acids produced by lactic acid bacteria (LAB) during the fermentation of sourdoughs have the ability to reduce the growth of different molds. However, this ability depends on the LAB used. For this reason, in this study, the proportions of different LAB were optimized to obtain aqueous extracts (AEs) from sourdough to reduce fungal growth in vitro, control the acetic acid concentration, and obtain a specific lactic to acetic acid ratio. In addition, the optimized mixtures were used to formulate partially baked bread (PBB) and evaluate the mold growth and bread quality during refrigerated storage. Using a simplex-lattice mixture design, various combinations of Lactiplantibacillus plantarum, Lacticaseibacillus casei, and Lactobacillus acidophilus were evaluated for their ability to produce organic acids and inhibit mold growth. The mixture containing only Lpb. plantarum significantly reduced the growth rates and extended the lag time of Penicillium chrysogenum and P. corylophilum compared with the control. The AEs' pH values ranged from 3.50 to 3.04. Organic acid analysis revealed that using Lpb. plantarum yielded higher acetic acid concentrations than when using mixed LAB. This suggests that LAB-specific interactions significantly influence organic acid production during fermentation. The reduced radial growth rates and extended lag times for both molds compared to the control confirmed the antifungal properties of the AEs from the sourdoughs. Statistical analyses of the mixture design using polynomial models demonstrated a good fit for the analyzed responses. Two optimized LAB mixtures were identified that maximized mold lag time, targeted the desired acetic acid concentration, and balanced the lactic to acetic acid ratio. The addition of sourdough with optimized LAB mixtures to PBB resulted in a longer shelf life (21 days) and adequately maintained product quality characteristics during storage. PBB was subjected to complete baking and sensory evaluation. The overall acceptability was slightly higher in the control without sourdough (7.50), followed by bread formulated with the optimized sourdoughs (ranging from 6.78 to 7.10), but the difference was not statistically significant (p > 0.05). The sensory analysis results indicated that the optimization was used to successfully formulate a sourdough bread with a sensory profile closely resembling that of a nonsupplemented one. The designed LAB mixtures can effectively enhance sourdough bread's antifungal properties and quality, providing a promising approach for extending bread shelf life while maintaining desirable sensory attributes.

Dynamic changes in aromas and precursors of edible fungi juice: mixed lactic acid bacteria fermentation enhances flavor characteristics.

Lactic acid bacteria (LAB) fermentation technology has been increasingly used in the deep processing of edible fungi. However, the flavor profiles of edible fungi products after mixed LAB fermentation have received less attention and how aromas changes during the mixed LAB fermentation are still open questions. In the present study, fermented Hericium erinaceus and Tremella fuciformis compound juice (FHTJ) was prepared by mixed LAB strains. We aimed to systematically monitor the dynamic changes of aromas and precursors throughout the fermentation process and a data-driven association network analysis was used to tentatively illustrate the mechanisms of formation between aromas and their precursors. Mixed LAB fermentation could enrich the aroma profile of FHTJ, reducing the unpleasant flavors such as nonanal and 1-octen-3-ol, as well as increasing the floral flavors such as ethyl acetate and α-pinene. Partial least squares-discriminant analysis and relative odor activity values revealed that 11 volatile chemicals were recognized as aroma-active markers. Volcano plot analysis showed that 3-octen-2-one (green flavor) was the key aroma-active marker in each stage, which was down-regulated in fermentation stages I, II and IV, whereas it was up-regulated in stage III. 3-Octen-2-one was significantly negatively correlated with organic acids, particularly pyruvate (r2 = -0.89). Ethyl caprylate (floral flavor) was up-regulated in the late fermentation stage, and showed a negative correlation with sugar alcohols and a positive correlation with organic acids, especially tartaric acid (r2 = 0.96). The present study demonstrates the beneficial effect of mixed LAB fermentation on flavor characteristics, providing guidance for fermented edible fungi juice flavor quality monitoring and control. © 2024 Society of Chemical Industry.

Enrichment and Characterization of Sheep Caecum Mixed Lactic Acid Bacteria as Potential Direct-fed Microbials (DFMs) in Livestock

Abstract Lactic Acid Bacteria (LAB) have been widely used as feed supplements in the form of live bacteria or Direct-fed microbials (DFMs) which are expected to have a positive impact on livestock productivity. However, each LAB strain has different characteristics so its ability to influence its host livestock will also be different. This research aims to characterize the LAB enrichment process obtained from the caecum of sheep. The sheep caecum LAB underwent re-inoculated while being enriched in MRS broth medium. After obtaining the LAB isolates, characterization was carried out in the form of pH measurements, total plate count, bacteriocin production, and bacterial kinetic growth. The results showed that LAB could be grown from the digesta of sheep caecum as seen from the decrease in the average pH of the growth medium reaching pH 4.14 with a bacterial colony count of 6,01 log CFU/ml. The grown LAB had a Ks value of 0.24 μM glucose and a μmax value of 2.69 OD. Apart from that, the clear zone test showed a positive result. In conclusion, Enrichment of mixed LAB cultures from sheep caecum has decreased environmental pH by 33%. Sheep caecum mixed LAB culture has easy growth characteristics and antimicrobial activity so it can be a suitable alternative DMF candidate. Further research focusing on the application of this LAB strain is needed to be able to determine the effect of bacteria on livestock.

Optimization of the fermentation process and antioxidant activity of mixed lactic acid bacteria for honeysuckle beverage.

The aim of the research was to obtain a high healthcare honeysuckle beverage with strong antioxidant activity. Honeysuckle (Lonicera japonica Thunb) was used as the raw material in this experiment. The effects of fermentation temperature, fermentation time, lactic acid bacteria inoculation amount, and sugar addition amount on the sensory quality of honeysuckle beverage were investigated by single factor test and orthogonal test, and the best process was obtained. The physicochemical indexes and antioxidant activity of honeysuckle beverages fermented with lactic acid bacteria were studied. The results showed that the fermentation temperature of the beverage was 37 °C, the fermentation time was 24 h, the inoculation amount of Lactiplantibacillus plantarum and Lactobacillus acidophilus mixed starter (1:1) was 3%, and 8% white granulated sugar was added. The highest sensory score was 87.30 ± 0.17, which was the optimal process. The honeysuckle liquid mixed inoculation with Lactiplantibacillus plantarum and Lactobacillus acidophilus was fermented for 24 h. The number of viable bacteria reached 9.84 ± 0.02 lg cfu/mL, the pH value was 3.10 ± 0.01, and the total polyphenol content was 7.53 ± 0.03 mg GAE/g. The number of lactic acid bacteria, pH, total polyphenol content, and free radical scavenging rate were significantly increased (p < 0.05) compared with the non-inoculated and single-inoculated lactic acid bacteria. To sum up, it was concluded that a better quality beverage could be obtained by fermenting a solution of honeysuckle with Lactiplantibacillus plantarum and Lactobacillus acidophilus mixed fermentation agent, providing a new approach and new ideas for the development of deep processing and fermented beverages using honeysuckle.

Phenotypic, Technological, Safety, and Genomic Profiles of Gamma-Aminobutyric Acid-Producing Lactococcus lactis and Streptococcus thermophilus Strains Isolated from Cow's Milk.

Gamma-aminobutyric acid (GABA)-producing lactic acid bacteria (LAB) can be used as starters in the development of GABA-enriched functional fermented foods. In this work, four GABA-producing strains each of Lactococcus lactis and Streptococcus thermophilus species were isolated from cow's milk, and their phenotypic, technological, and safety profiles determined. Genome analysis provided genetic support for the majority of the analyzed traits, namely, GABA production, growth in milk, and the absence of genes of concern. The operon harboring the glutamate decarboxylase gene (gadB) was chromosomally encoded in all strains and showed the same gene content and gene order as those reported, respectively, for L. lactis and S. thermophilus. In the latter species, the operon was flanked (as in most strains of this species) by complete or truncated copies of insertion sequences (IS), suggesting recent acquisition through horizontal gene transfer. The genomes of three L. lactis and two S. thermophilus strains showed a gene encoding a caseinolytic proteinase (PrtP in L. lactis and PrtS in S. thermophilus). Of these, all but one grew in milk, forming a coagulum of good appearance and an appealing acidic flavor and taste. They also produced GABA in milk supplemented with monosodium glutamate. Two L. lactis strains were identified as belonging to the biovar. diacetylactis, utilized citrate from milk, and produced significant amounts of acetoin. None of the strains showed any noticeable antibiotic resistance, nor did their genomes harbor transferable antibiotic resistance genes or genes involved in toxicity, virulence, or pathogenicity. Altogether these results suggest that all eight strains may be considered candidates for use as starters or components of mixed LAB cultures for the manufacture of GABA-enriched fermented dairy products.

Effects of Different Lactic Acid Bacteria in Single or Mixed Form on the Fermentative Parameters and Nutrient Contents of Early Heading Triticale Silage for Livestock.

Lactic acid bacteria (LAB) are excellent anaerobic fermenters that produce highly valuable grass-based animal feed containing essential nutrients. In the present study, an ensiling process was used to improve anaerobic fermentation in triticale silage under different moisture conditions with LAB. The triticale was treated with either a single bacterium or combined LAB and then vacuum-sealed. After 180 and 360 days of storage, the silage's fermentation characteristics, microbial changes and nutrient contents were analyzed. The pH of the silage was significantly lower than the control silage. There was a significant difference in the pH values between the silages treated with single or mixed LAB. The LAB treatment led to a substantial increase in lactic acid (LA), a decrease in butyric acid (BA), and marginal levels of acetic acid (AA). The LA content after the mixed LAB treatment was significantly higher than that after the single culture LAB treatment. After single or combined inoculant treatments, the LAB population in the silage increased, while the yeast and mold levels decreased. These findings suggest that the addition of LAB to silage during ensiling could enhance the nutritional quality and reduce unwanted microbial growth. The mixed LAB treatments produced silage with a significantly higher nutritional value than the single LAB treatments.

Preliminary Investigations on the Therapeutic Efficacy and Safety of Mixed Probiotic Lactic Acid Bacteria on Albino Rats Challenged with Shigella dysenteriae

This study investigates the potential of lactic acid bacteria (LAB) from the Nigerian beverage “kunun zaki” as alternative therapeutic agents against Shigella dysenteriae infections. In light of rising antibiotic resistance, the decline in probiotic usage prompted interest in LAB’s role in countering bacterial dysentery. Shigella dysenteriae, a significant cause of dysentery in developing nations, prompted this research which aims to carry out a preliminary investigation on the therapeutic efficacy and safety of mixed probiotic lactic acid bacteria on albino rats challenged with Shigella dysenteriae. Lactic acid bacteria, known for treating infections, were isolated from the beverage and tested against Shigella dysenteriae. The study employed 15 albino rats for in vivo trials, inducing diarrhea and treating with Lactococcus lactis and Lactobacillus brevis separately (T1 and T2) and combined in a 1 : 1 ratio (T3). Clinical parameters were observed before and after treatment. This revealed that L. lactis and L. brevis administration lowered rectal temperature from an average of 42°C caused by infection to 36.5°C. Stool consistency improved from light brown loose to dark brown semisolid, signifying reduced diarrhea. Bacteriological analysis displayed significant reduction ( p &lt; 0.05 ) in Shigella counts in rat intestines across all treatments— 220 ± 2.88 C F U / g to 19.00 ± 1.77 C F U / g , 8.33 ± 0.88 C F U / g , and 65.00 ± 2.88 C F U / g for T1, T2, and T3, respectively. The mixed LAB treatment was notably effective. Lactic acid bacteria counts increased significantly in Shigella-treated rats versus the positive control. Hematology and liver function parameters showed no significant differences between treatments and untreated controls. Lactic acid bacteria from “kunun zaki” exhibited curative potential, individually or combined, against Shigella dysenteriae. These lactic acid bacteria also positively influenced gut microbiota in Shigella-infected albino rats.

Effect of fermentation of Danisco mixed lactic acid bacteria and single Bifidobacterium lactis HCS04-001 on metabolites of soy yogurt

Abstract In this study, the effects of Danisco mixed lactic acid bacteria and single Bifidobacterium lactis HCS04-001 fermentation on metabolites in soy yogurt were investigated. The main volatile metabolites in sample D fermented by Danisco mixed lactic acid bacteria were aldehydes, followed by alcohols and ketones. In contrast, the main flavor substances in sample SQ fermented by single Bifidobacterium lactis HCS04-001 were alcohols followed by aldehydes. L-Arginine, S-Adenosylhomocysteine, Glutamyltyrosine, Gly-Trp, Ser-Trp, Ile-Ser-Leu, Pro-Val-Leu etc. and D-Ornithine, Citrulline, Glutamylproline, organic acid were the main non-volatile differential metabolites that distinguished the soy yogurt samples. Arginine biosynthesis and glutathione metabolism were important pathways leading to differences in metabolic profiles. This study provides detailed insight into the metabolic properties of commercial Danisco mixed lactic acid bacteria and single Bifidobacterium lactis HCS04-001 fermentations, which will contribute to the development of soy yogurt with good nutritional and sensory qualities.

Improvement of blood lipid metabolism and obesity through the administration of mixed lactic acid bacteria including Lactobacillus plantarum K-1 in mice fed a high-fat diet

Improvement of blood lipid metabolism and obesity through the administration of mixed lactic acid bacteria including <i>Lactobacillus plantarum</i> K-1 in mice fed a high-fat diet

Adapted tissue assay for the assessment of ileal granulocyte degranulation following in ovo inoculation with select bacteria or coccidial challenge in chickens.

A previously described heterophil degranulation assay was adapted for use with ileal mucosal tissue via quantification of β-D-glucuronidase and assay end product 4-methylumbelliferone (4-MU). Three initial experiments evaluated the effect of in ovo inoculations of Citrobacter freundii (CF) or mixed lactic acid bacteria (LAB) on ileal granulocyte degranulation. Inoculations were administered on embryonic d18, body weights (BW) were recorded on day of hatch (DOH) and d10 to calculate body weight gain (BWG), and ileal mucosal scrapings were collected on DOH or d10 for the 4-MU assay. In all experiments, treatments were statistically analyzed relative to control groups. Treatments minimally affected BWG in all in ovo experiments (p > 0.05) relative to respective control groups. Similarly, ileal degranulation in in ovo treatments did not statistically differ (p > 0.05). Based on BWG, in ovo treatments may have induced low-level inflammation unable to elicit detectable changes via the 4-MU assay. Four subsequent experiments were conducted to evaluate effects of Eimeria maxima (EM) on ileal degranulation. Treatments included non-inoculated controls and low, medium, or high EM infection. Across all four experiments, final BW or BWG over the inoculation period were suppressed (p < 0.05) in EM groups relative to respective controls with the exception of EM-low (p = 0.094) and EM-medium (p = 0.096) in one trial. Ileal mucosal scrapings for the 4-MU assay were collected on day of peak lesions. Resulting values were reduced (p < 0.05) for EM treated birds in three experiments with the exception of EM-medium (p = 0.247). No differences were observed in one experiment (p = 0.351), which may have been attributed to a variation in strain of infecting Eimeria. Although refinement for low level inflammation is warranted, results indicate successful adaptation of the 4-MU assay for use with intestinal tissue during significant gastrointestinal inflammation.

Optimised fermentation of bamboo waste using three types lactic acid bacteria and forming mechanism of binderless particleboard

In this study, to improve the performance of bamboo binderless particleboard, the fermentation process of bamboo waste using three kinds of lactic acid bacteria was optimised. The effects of the ratio of mixed lactic acid bacteria and fermentation time on the performance of bamboo particles were investigated. The basic physical and mechanical properties of bamboo binderless particleboards was tested. The forming mechanism of the bamboo binderless particleboard was investigated. The results indicate that lactic acid bacterial fermentation caused in the degradation of bamboo components and the increase of lignin content. With the extension of fermentation time, pH of bamboo particles first decreased and then increased, and reached the lowest on the eight day of fermentation; the aerobic stability was greatly improved. Fermentation can also improve the strength and waterproofing performance of bamboo binderless particleboard. Lactobacillus buchneri has relatively good fermentation efficiency. Mixed lactic acid bacterial fermentation has a higher decomposition rate than single lactic acid bacterial fermentation. Improved physical and mechanical properties of bamboo binderless particleboard was obtained when the mixing ratio of Lactobacillus paracasei, Lactobacillus buchneri, and Lactobacillus plantarum was 1:2:1 and fermentation was carried out for eight days. Fermentation with lactic acid bacterial caused the degradation of bamboo components and the production of short-chain sugars, and promoted the formation of hydrogen bond and furfural during hot pressing, which contributed to the bonding of bamboo binderless particleboard.

Lychee pulp phenolics fermented by mixed lactic acid bacteria strains promote the metabolism of human gut microbiota fermentation in vitro.

Lychee pulp phenolics possess excellent biological activities, however, changes in phenolic substances after microbial treatments are unknown. Herein, lychee pulp was fermented by Lactobacillus plantarum, Lactobacillus rhamnosus, and a mixed strain of the two, followed by an investigation of the products' colonic fermentation. In comparison to single-strain fermentation, mixed-strain fermentation significantly increased catechin and quercetin. In addition, lychee phenolics fermented by mixed strains were more conducive to the growth of gut microbiota. The results of HPLC-DAD showed that colonic fermentation further promoted the release of lychee phenolics. There was a notable increase in the content of gallic acid and quercetin, while multiple phenolics were degraded. Quercetin-3-O-rutinose-7-O-α-L-rhamnoside (QRR) and rutin were catabolized into quercetin by gut microbiota, and 4-hydroxybenzoic acid was produced from the metabolism of QRR and procyanidin B2. Lychee phenolics fermented by mixed lactic acid bacteria were easily metabolized and transformed by gut microbiota. These findings indicate that lychee pulp fermented by mixed lactic acid bacteria possesses probiotic potential, which is of great significance for the development of functional probiotic products.

Enhanced silage pretreatment improving the biochemical methane potential of Miscanthus sinensis.

The choice of silage additives is an important factor for the storage of silage. One standard ensiling method and two enhanced ensiling methods (using natural silage, silage with mixed lactic acid bacteria, and silage with acetic acid, respectively) were carried out on Miscanthus sinensis. To determine the effects of these different methods, the biochemical methane potential (BMP) was determined. The results revealed that ensiling with acetic acid was the best method among the three ensiling methods. Acetic acid could quickly reduce the pH of the system to inhibit the growth of harmful bacteria. The rate of loss of dry matter was 0.92% when acetic acid was added, and the cumulative methane production was 149.6mL·g-1 volatile solids. From an analysis of correlations between the properties and BMP of silage, the contents of acetic acid and total volatile fatty acids were significantly correlated with the BMP. This study provides a theoretical basis for improving the BMP of M. sinensis and achieving better effects of silage.

Anti-inflammation and gut microbiota regulation properties of fatty acids derived from fermented milk in mice with dextran sulfate sodium-induced colitis.

The by-products of milk fermentation by lactic acid bacteria provide potential health benefits to the balance of host intestinal microflora. In this study, the anti-inflammatory properties of fatty acids from monoculture-strain (Lactiplantibacillusplantarum A3) and multiple-strain (Streptococcus thermophilus, Lactobacillus bulgaricus, and L. plantarum A3 1:1:2) fermented milk were evaluated in a mouse model of dextran sulfate sodium-induced colitis, and the gut microbiota regulation properties of the fatty acids were also investigated. Results showed that fatty acids can attenuate the inflammatory response by inhibiting the expression of inflammatory factors IL-6 and tumor necrosis factor-α, and blocking the phosphorylation of the JNK in MAPK signal pathway. In addition, the relative abundance of the taxa Akkermansia and Lactobacillus were both enriched after the fatty acid intervention. This finding suggests that fatty acids from the milk fermentation with mixed lactic acid bacteria starters can reduce the severity of dextran sulfate sodium-induced colitis and enhance the abundance of the probiotics in the mice intestinal tract.

Structural, Physicochemical, and Functional Properties of Wheat Bran Insoluble Dietary Fiber Modified With Probiotic Fermentation.

Insoluble dietary fiber (IDF) were isolated from wheat bran (WB) after microbial fermentation with single or mixed strain [Lactobacillus plantarum, Lactobacillus acidophilus, Bacillus subtilis or mixed lactic acid bacteria (L. plantarum and L. acidophilus with ration of 1:1)]. Structure, physicochemical, functional properties, and antioxidant activity of the wheat bran insoluble dietary fiber (W-IDF) modified by fermentation were studied. Fourier transformed infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) analysis suggested the successful modification of W-IDF. After fermentation with L. plantarum and mixed lactic acid bacteria, the water retention capacity (WRC), oil retention capacity (ORC), and water swelling capacity (WSC) of W-IDF were improved. The sodium cholate adsorption capacity (SCAC), and cation exchange capacity (CEC) of W-IDF modified with L. acidophilus fermentation were significantly increased. Although the cholesterol adsorption capacity (CAC) of W-IDF decreased after modification with probiotic fermentation, nitrite ion adsorption capacity (NIAC), and total phenolic content (TPC) were enhanced. Additionally, W-IDF modified by fermentation with B. subtilis or mixed lactic acid bacteria exhibited superior antioxidant capacity verified by DPPH, ABTS and total reducing power assays. Results manifested that microbial fermentation is a promising methods to modify the W-IDF to provide high-quality functional IDF for food processing and human health management.

Formulation, Processing and Characterization of Fermented Probiotic Mango Juice Using Selected Starter Cultures

Probiotics are live microorganisms added to food products to confer health benefits such as gut health, cancer protection and improved immunity when consumed. Fruits juices are considered as potential channels for delivering probiotics as they contain essential nutrients and low pH suitable for the growth of probiotics. The study was undertaken to formulate, process and characterize fermented probiotic mango fruit juice using three different mixed lactic acid bacteria cultures: Abt-5® culture (Streptococcus thermophillus, Bifidobacterium and Lactobacillus acidophilus); Fiti® culture (Lactobacillus rhamnosus GR-1) and Yo-mix® culture (Streptoc.occus thermophillus and Lactobacillus delbruikii ssp bulgaricus). The viability of the cultures was also assessed. The mango juice was formulated using mango pulp to water ratios of 100:0, 25:75, 50:50 and 75:25 (v/v) and adjusted to 17° brix by adding cane sugar. The formulated mango juices were pasteurized at 90 °C for 1 minute and cooled to 10 °C. Sensory evaluation was carried out to determine the most preferred formulation of the fruit juice before fermentation. The preferred mango juice samples were cooled to 402 °C and incubated with the three different mixed bacteria cultures (1 g/l) for 0, 12, 16, 24, 36, 48 and 72 hours. The final product stored at 4 °C. Analysis for sensory evaluation, culture viability, pH, total soluble solids (TSS) and total titratable acidity (TTA) was done. The 50:50 ([mango pulp: water) mango fruit juice formulation was significantly different (p&lt;0.05) from the other samples in consistency and was rated the best in overall acceptability. There was general increase in cell count in all cultures with mango juice fermented with Lactobacillus rhamnosus GR-1 for 48 hours recording the highest viable cell count of log10 9.14 CFU/ml. Highest pH decrease was observed in 50:50 formulation with significant (p&lt;0.05) increase in TTA from 0.15% to 0.69% using Lactobacillus rhamnosus GR-1 within 72 hours. Subsequently, the TSS decreased from 17° brix to 14.47° brix. The study showed that the three mixed were able to utilize nutrients present in the formulated mango juice during fermentation as demonstrated by decrease in pH and TSS. The study therefore recommends that further research should be done on the probiotic fermented mango juice to determine the change in physco-chemical characteristics and culture viability during storage.

Lactic Acid Bacteria Mixture Isolated From Wild Pig Alleviated the Gut Inflammation of Mice Challenged by Escherichia coli.

Wild pigs usually showed high tolerance and resistance to several diseases in the wild environment, suggesting that the gut bacteria of wild pigs could be a good source for discovering potential probiotic strains. In our study, wild pig feces were sequenced and showed a higher relative abundance of the genus Lactobacillus (43.61% vs. 2.01%) than that in the domestic pig. A total of 11 lactic acid bacteria (LAB) strains including two L. rhamnosus, six L. mucosae, one L. fermentum, one L. delbrueckii, and one Enterococcus faecalis species were isolated. To investigate the synergistic effects of mixed probiotics strains, the mixture of 11 LAB strains from an intestinal ecology system was orally administrated in mice for 3 weeks, then the mice were challenged with Escherichia coli ATCC 25922 (2 × 109 CFU) and euthanized after challenge. Mice administrated with LAB strains showed higher (p < 0.05) LAB counts in feces and ileum. Moreover, alterations of specific bacterial genera occurred, including the higher (p < 0.05) relative abundance of Butyricicoccus and Clostridium IV and the lower (p < 0.05) abundance of Enterorhabdus in mice fed with mixed LAB strains. Mice challenged with Escherichia coli showed vacuolization of the liver, lower GSH in serum, and lower villus to the crypt proportion and Claudin-3 level in the gut. In contrast, administration of mixed LAB strains attenuated inflammation of the liver and gut, especially the lowered IL-6 and IL-1β levels (p < 0.05) in the gut. Our study highlighted the importance of gut bacterial diversity and the immunomodulation effects of LAB strains mixture from wild pig in gut health.

Screening of mixed lactic acid bacteria starter and its effects on the quality and flavor compounds of fermented Lentinus edodes

The lactic acid bacteria (LAB) with excellent fermented performance were screened for Lentinus edodes fermentation by measuring the growth status and acid producing capacity of different LAB in L. edodes, and the optimal mixed ratio of LAB was selected for the L. edodes fermentation through the mixed fermented test. Factors affecting the quality of fermented L. edodes were optimized by single factor experiment and response surface experiment. The results showed that when the mixed ratio of LAB was Lactobacillus delbrueckii subsp. bulgaricus: Lactiplantibacillus plantarum: Lacticaseibacillus rhamnous = 3:1:2, fermented L. edodes had the best fermented quality. The optimized process parameters of mixed LAB fermented L. edodes were as follows: fermentation temperature of 37 °C, salt content of 1%, and inoculation amount of 2.7%. Under this process, the total acid and sensory score of fermented L. edodes were 0.88 g/100 g and 81.7 points, respectively. Compared with the unfermented L. edodes, the contents of acids and ketones in the fermented L. edodes increased by 2.16% and 17.8%, while the contents of alcohols, aldehydes and phenols were relatively reduced by 3.66%, 7.42%, and 3.87%, respectively. This study provides a theoretical basis for the development of LAB fermented food of L. edodes.