Lactobacillus Group Research Articles

Strategies for enhancing short- and medium-chain fatty acids synthesis from corn stover-based sugar: A new perspective on co-culture

In this study, corn stover-based sugar served as the initial carbon source to investigate the impact of different co-culture strategies on the synthesis of short- and medium-chain fatty acids (SMCFAs) through carbon chain elongation (CCE). The results indicated that the sequential inoculation outperformed simultaneous inoculation in the M. elsdenii and Lactobacillus groups. The inclusion of Lactobacillus significantly enhanced substrate utilization, generating lactate that facilitated the integration of odd carbon carboxylates (such as propionate and valerate) into the CCE products. The caproate concentration in the M. elsdenii+L. pentosus group reached 3.4 g/L, which was 1.3 times that in the control group. Furthermore, the introduction of C. kluyveri effectively boosted the synthesis of butyrate and caproate through CCE using ethanol as an electron donor within the co-culture setup of the M. elsdenii+C. kluyveri group. Moreover, the carbon efficiency of the co-culture group increased by 10–21 % compared to the control group, and the cell protein titer was 1.5–2 times higher than that of the control group. This study has established a method for co-producing SMCFAs and cell proteins utilizing bio-sugars through a co-culture approach, offering implications for lignocellulose utilization and potential high-value applications of SMCFAs in the future.

Protective effects of a lactobacilli mixture against Alzheimer’s disease-like pathology triggered by Porphyromonas gingivalis

Porphyromonas gingivalis (P. gingivalis) is one of the pathogens involved in gingival inflammation, which may trigger neuroinflammatory diseases such as Alzheimer’s disease (AD). This study aimed to investigate the protective (preventive and treatment) effects of a lactobacilli mixture combining Lactobacillus reuteri PTCC1655, Lactobacillus brevis CD0817, Lacticaseibacillus rhamnosus PTCC1637, and Lactobacillus plantarum PTCC1058 against P. gingivalis-induced gingival inflammation and AD-like pathology in rats. These probiotic strains exhibited cognitive enhancement effects, but this study proposed to assess their activity in a mixture. To propose a probable mechanism for P. gingivalis cognitive impairments, the TEs balance were analyzed in hippocampus and cortex tissues. Animals were divided into five groups: the control, lactobacilli, P. gingivalis, lactobacilli + P. gingivalis (prevention), and P. gingivalis + lactobacilli group (treatment) groups. The behavioral and histopathological changes were compared among them. Finally, The Trace elements (TEs) levels in the hippocampus and cortex tissues were analyzed. The palatal tissue sections of the P. gingivalis infected rats showed moderate inflammation with dense infiltration of inflammatory cells, a limited area of tissue edema, and vascular congestion. Additionally, passive avoidance learning and spatial memory were impaired. Histopathological tests revealed the presence of Aβ-positive cells in the P. gingivalis group. While the Aβ-positive cells decreased in the treatment group, their formation was inhibited in the preventive group. Administration of a mixture of lactobacilli (orally) effectively mitigated the gingival inflammation, Aβ production, and improved learning and memory functions. Moreover, Zn, Cu, and Mn levels in the hippocampus were dramatically elevated by P. gingivalis infection, whereas lactobacilli mixture mitigated these disruptive effects. The lactobacilli mixture significantly prevented the disruptive effects of P. gingivalis on gingival and brain tissues in rats. Therefore, new formulated combination of lactobacilli may be a good candidate for inhibiting the P. gingivalis infection and its subsequent cognitive effects. The current study aimed to evaluate the effects of a lactobacilli mixture to manage the disruptive effects of P. gingivalis infection on memory.

Antibacterial potential of queen pineapple (Ananas comosus (L.) Merr Var. Queen) peel extract on the growth of Lactobacillus acidophilus bacteria

Based on the Global Burden of Disease Study in 2017, the prevalence of caries in each country reached 20% to more than 50%. Caries is formed due to the role of several factors including host, agent (microorganisms), substrate, and time. Bacteria involved in the origin of caries formation such as Lactobacillus group bacteria found in the oral cavity which can cause dental caries, one of which is Lactobacillus acidophilus. The use of natural cleansers is highly recommended to remove residual bacteria as an effort to prevent caries. Queen Pineapple (Ananas comosus (L.) Merr Var. Queen) is a fruit that contains very complex compounds that can act as anticarcinogenic and antibacterial. This study aims to determine the Minimum Bactericidal Concentration (MBC) and Minimum Inhibitory Concentration (MIC) against the growth of Lactobacillus acidophilus bacteria. This type of research was a laboratory experimental type with posttest only control group design. This study used the dilution method of the number of samples, namely concentrations of 0.781%, 1.56%, 3.125%, 6.25%, 12.5%, 25%, 50%, 100%, positive controls and negative controls. This study was conducted 3 times repetition. Manual calculation of the number of bacterial colonies that grow on nutrient agar media and expressed in colony forming units (CFU) which will determine the MBC and MIC. The Shapiro-Wilk test showed a p value> 0.05 at all concentrations and normally distributed data, but when tested for homogeneity the data was not homogeneous so that the non-parametric statistical test continued using the Kruskal Wallis test showing a value of p < 0.05. Conclusion: Colony count results showed that the concentration of 3.12% can inhibit the visible growth of Lactobacillus acidophilus bacteria which is stated as the Minimum Inhibitory Concentration (MIC) and can prevent growth after subculture to antibiotic-free medium at a concentration of 6.25% which is stated as the Minimum Bactericidal Concentration (MBC).

Protective Effects of Lactobacillus Strains Against Oxidative Stress and Immune Suppression in Mice Receiving Aflatoxin-Contaminated Diet.

Mycotoxins like aflatoxins pose a significant threat to the health of both people and animals because of their deadly effects. This study aimed to investigate the potential of Lactobacillus strains in reducing the toxicity caused by aflatoxins in mice receiving a diet contaminated with aflatoxins. The mice were split up into various treatment groups, including a control group, an aflatoxin-treated group, and groups treated with the aflatoxin-contaminated diet along with Lactobacillus strains. Various parameters, including liver enzymes, blood parameters, malondialdehyde (MDA) levels, morphometric analysis of ileum, and gene expression, were analyzed to assess the effectiveness of the Lactobacillus strains in mitigating aflatoxins toxicity. Results showed that mice in the aflatoxin-treated group had increased MDA levels, indicating oxidative stress. Alternatively, the Lactobacillus cocktail treatment group showed a decreasing trend in MDA levels, suggesting a reduction in lipid peroxidation. The morphometric analysis of ileum tissue demonstrated that the Lactobacillus-treated group exhibited improved structural integrity compared to the aflatoxin-treated group. Additionally, gene expression analysis revealed that the Lactobacillus treatment attenuated the downregulation of SOD gene expression and mitigated the upregulation of iNOS gene expression induced by aflatoxins. These findings suggest that Lactobacillus strains have the potential to reduce aflatoxin-induced toxicity by alleviating oxidative stress, preserving intestinal tissue integrity, and modulating gene expression associated with antioxidant defense and inflammation. This study provides evidence for the beneficial effects of Lactobacillus strains in reducing aflatoxin toxicity in mice. The findings obtained may contribute to the development of preventive or therapeutic strategies against mycotoxin-induced toxicity.

Isolation and Characterization of Bacteriocin Producing Levilactobacillus brevis Strain ABRIINW-K from Buffalo Dung

Bacteriocins are proteins secreted by many species of bacteria to inhibit other bacteria, thus eliminating competitors to gain resources. Bacteria from the Lactobacillus group are known for their applications as probiotics and food preservatives. They have earned a reputation for producing substances that inhibit the growth of other microorganisms, which include organic acids, diacetyl, and bacteriocins. Produced by the ribosomes, bacteriocins are cationic proteins that inhibit other bacteria coexisting within a shared ecological habitat. Due to their potential uses in a variety of applications large-scale production of Bacteriocins would be necessary. The study aimed to identify and characterize Lactobacillus bacteria that produce potent bacteriocins and to analyze the antimicrobial activity and stability of the isolated bacteriocin under various physical and biochemical conditions. A total of 50 samples including buffalo dung, cheese, and rhizospheric region of plants were screened to isolate 8 Lactobacillus Li-1, Li-2, Li-3, Li-4, Li-5, Li-6, Li-7, and Li-8, confirmed by gram staining and other biochemical tests. The cell free supernatant from the Li-3 strain showed higher inhibition of Escherichia coli and Staphylococcus aureus, as compared to the other isolated strains. Li-3 strain was further identified as Levilactobacillus brevis strain ABRIINW-K by 16S rRNA gene sequencing. The bacteriocin isolated from this strain is a thermostable peptide (~6kDa), which is characteristic of class II bacteriocins, with potent antibacterial activity against Lactobacillus rhamnosus, Escherichia coli, and Salmonella enterica.

A potential therapeutic strategy of an innovative probiotic formulation toward topical treatment of diabetic ulcer: an in vivo study

BackgroundThe probiotic potential of Lacticacid bacteria has been studied in various medical complications, from gastrointestinal diseases to antibiotic resistance infections recently. Moreover, diabetic ulcer (DU) is known as one of the most significant global healthcare concerns, which comprehensively impacts the quality of life for these patients. Given that the conventional treatments of DUs have failed to prevent later complications completely, developing alternative therapies seems to be crucial.MethodsWe designed the stable oleogel-based formulation of viable probiotic cells, including Lactobacillus rhamnosus (L. rhamnosus), Lactobacillus casei (L. casei), Lactobacillus fermentum (L. fermentum), and Lactobacillus acidophilus (L. acidophilus) individually to investigate their effect on wound healing process as an in vivo study. The wound repair process was closely monitored regarding morphology, biochemical, and histopathological changes over two weeks and compared it with the effects of topical tetracycline as an antibiotic approach. Furthermore, the antibiofilm activity of probiotic bacteria was assessed against some common pathogens.ResultsThe findings indicated that all tested lactobacillus groups (excluded L. casei) included in the oleogel-based formulation revealed a high potential for repairing damaged skin due to the considerably more levels of hydroxyproline content of tissue samples along with the higher numerical density of mature fibroblasts cell and volume density of hair follicles, collagen fibrils, and neovascularization in comparison with antibiotic and control groups. L. acidophilus and L. rhamnosus showed the best potential of wound healing among all lactobacillus species, groups treated by tetracycline and control groups. Besides, L. rhamnosus showed a significant biofilm inhibition activity against tested pathogens.ConclusionsThis experiment demonstrated that the designed formulations containing probiotics, particularly L. acidophilus and L. rhamnosus, play a central role in manipulating diabetic wound healing. It could be suggested as an encouraging nominee for diabetic wound-healing alternative approaches, though further studies in detailed clinical trials are needed.

Revealing the spoilage characteristics of refrigerated prepared beef steak by advanced bioinformatics tools.

Although microorganisms are the main cause of spoilage in prepared beef steaks, very few deep spoilage mechanisms have been reported so far. Aiming to unravel the mechanisms during 12 days of storage at 4 °C affecting the quality of prepared beef steak, the present study investigated the changes in microbial dynamic community using a combined high-throughput sequencing combined and bioinformatics. In addition, gas chromatography-mass spectrometry combined with multivariate statistical analysis was utilized to identify marker candidates for prepared steaks. Furthermore, cloud platform analysis was applied to determine prepared beef steak spoilage, including the relationship between microbiological and physicochemical indicators and volatile compounds. The results showed that the dominant groups of Pseudomonas, Brochothrix thermosphacta, Lactobacillus and Lactococcus caused the spoilage of prepared beef steak, which are strongly associated with significant changes in physicochemical properties and volatile organic compounds (furan-2-pentyl-, pentanal, 1-octanol, 1-nonanol and dimethyl sulfide). Metabolic pathways were proposed, among which lipid metabolism and amino acid metabolism were most abundant. The present study is helpful with respect to further understanding the relationship between spoilage microorganisms and the quality of prepared beef steak, and provides a reference for investigating the spoilage mechanism of dominant spoilage bacteria and how to extend the shelf life of meat products. © 2024 Society of Chemical Industry.

Effects of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets on the Structure and Function of the Intestinal Flora in Rabbits Undergoing Hepatic Artery Infusion Chemotherapy.

Few studies have explored the biological mechanism by which probiotics alleviate adverse reactions to chemotherapy drugs after local hepatic chemotherapy perfusion by regulating the intestinal flora. This study investigates the effects of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets on the intestinal microbial structure and intestinal barrier function, as well as the potential mechanism in rabbits after local hepatic chemotherapy infusion. Eighteen New Zealand White rabbits were randomly divided into a control group, a hepatic local chemotherapy perfusion group, and a hepatic local chemotherapy perfusion + Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets group to assess the effects of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets on the adverse reactions. The administration of Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets alleviated the intestinal flora disorder caused by local hepatic perfusion chemotherapy, promoted the growth of beneficial bacteria, and inhibited the growth of harmful bacteria. The Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets also reduced the levels of serum pro-inflammatory cytokines and liver injury factors induced by local hepatic perfusion chemotherapy. Our findings indicate that Combined Live Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus Cereus Tablets can ameliorate the toxicity and side effects of chemotherapy by regulating intestinal flora, blocking pro-inflammatory cytokines, reducing liver injury factors, and repairing the intestinal barrier. Probiotics may be used as a potential alternative therapeutic strategy to prevent the adverse reactions caused by chemotherapy with local hepatic perfusion.

Effect of probiotic feed supplementation on skin ulceration syndrome in Apostichopus japonicus

Skin ulceration syndrome is among the most harmful diseases in sea cucumber (Apostichopus japonicus). The annual loss due to this disease is more than 1 billion dollars, which seriously affected the healthy and sustainable development of A. japonicus. In this paper, animals were divided into 4 experimental groups: a control group given basic feed, experimental groups with 1% Lactobacillus, 1% Bacillus, 1% mixture with 0.5% Lactobacillus and 0.5% Bacillus added to the basic feed. After feeding for 60 days, the samples were taken to analyze the growth performance, digestive enzyme activity, and immune indexes of A. japonicus. Furthermore, the resistance to the skin ulceration syndrome of A. japonicus was analyzed. The results showed that the probiotics promoted the growth performance of A. japonicus, the weight gain rate of the control group was 120.08±12.07%, the weight gain rate of the Lactobacillus group was 152.11±10.06%, the weight gain rate of the Bacillus group was 148.03±9.88%, and the weight gain rate of the mixed bacteria group was as high as 210.11±19.41%. The digestive enzyme activities in the intestinal tract of A. japonicus increased significantly in the probiotic-added groups, and the mixed bacteria were more effective in enhancing the digestive enzyme activities than single Bacillus and Lactobacillus. In addition, the probiotics could significantly increase the phagocytosis rate of the body cavity cells of A. japonicus. The phagocytic rate of Lactobacillus and Bacillus subtilis was comparable; the mixed probiotics were significantly higher than those of single probiotics, and this phagocytic rate gradually increased over time. After Vibrio splendidus and Pseudoalteromonas infection, the mortality rate of A. japonicus in the probiotic-added group was reduced, which indicated that probiotics could improve the immunity of A. japonicus, and the ability to resist the infection of Vibrio splendidus and Pseudoalteromonas was enhanced. Bacillus exhibits superior antimicrobial ability compared to Lactobacillus, and the mixed strain displays the most effective antimicrobial properties. This study provided a scientific basis for effectively preventing and controlling skin ulceration syndrome in the aquaculture of A. japonicus.

Microbial interventions in yak colibacillosis: Lactobacillus-mediated regulation of intestinal barrier.

The etiology of Escherichia coli in yaks, along with its drug resistance, results in economic losses within the yak breeding industry. The utilization of lactic acid bacteria treatment has emerged as a viable alternative to antibiotics in managing colibacillosis. To elucidate the therapeutic mechanisms of Lactobacillus against Escherichia coli-induced intestinal barrier damage in yaks, we employed yak epithelial cells as the experimental model and established a monolayer epithelial barrier using Transwell. The study encompassed four groups: a control group, a model group (exposed to E. coli O78), a low-dose Lactobacillus group (E. coli O78 + 1 × 105CFU LAB), and a high-dose Lactobacillus group (E. coli O78 + 1 × 107CFU LAB). Various techniques, including transmembrane resistance measurement, CFU counting, RT-qPCR, and Western Blot, were employed to assess indicators related to cell barrier permeability and tight junction integrity. In the Model group, Escherichia coli O78 significantly compromised the permeability and tight junction integrity of the yak epithelial barrier. It resulted in decreased transmembrane resistance, elevated FD4 flux, and bacterial translocation. Furthermore, it downregulated the mRNA and protein expression of MUC2, Occludin, and ZO-1, while upregulating the mRNA expression and protein expression of FABP2 and Zonulin, thereby impairing intestinal barrier function. Contrastingly, Lactobacillus exhibited a remarkable protective effect. It substantially increased transmembrane resistance, mitigated FD4 flux, and reduced bacterial translocation. Moreover, it significantly upregulated the mRNA and protein expression of MUC2, Occludin, and ZO-1, while downregulating the mRNA and protein expression of FABP2 and Zonulin. Notably, high-dose LAB demonstrated superior regulatory effects compared to the low-dose LAB group. In conclusion, our findings suggest that Lactobacillus holds promise in treating yak colibacillosis by enhancing mucin and tight junction protein expression. Furthermore, we propose that Lactobacillus achieves these effects through the regulation of Zonulin.

Short term antibiotic effects on gut microbiome in Indian preschoolers: A 16S rRNA analysis

Objectives: Antibiotic use is associated with dysbiosis of the gut microbiome. The objective of this study is to investigate the effect of antibiotics on gut composition in children aged 3–5 years receiving antibiotics compared to children who did not receive antibiotics. Materials and Methods: A total of 54 participants aged 3–5 years were included in this multi-centric cohort study. Participants were divided into two equal groups, that is the treatment-experienced group (Group 1, n = 27, antibiotic) and the treatment-not-experienced group (Group 2, n = 27, non-antibiotic). Stool samples of study participants were collected on days 0 and 5 (± 1 day) and analyzed using 16Svedberg ribosomal ribonucleic acid (16S rRNA) gene sequencing. Statistical Analysis: The Kruskal-Wallis H-test and Benjamini-Hochberg FDR correction were applied to determine the differentially abundant pathways across the zones using Statistical Analysis of Metagenomic Profiles (STAMP) (v2.1.3). Results: A non-significant increase in the mean abundance of the Phyla Bacteroidota, Proteobacteria, Actinobacteria, and Verrucomicrobiota was observed in both groups from day 0 to day 5. An alteration in the Firmicutes/Bacteroidetes ratio was observed. A significant (P < 0.05) abundance of genus Enterobacteriaceae, Enterococcaceae, and Lactobacillaceae was observed in the participants with antibiotic treatment. The relative abundance of families Enterococcus, Lactobacillus, Sellimonas, Ruminococcus, Torques, and Eggerthella groups was observed to be significantly higher (P < 0.05) in participants with antibiotic treatment. Beta-diversity indices revealed significant differences at group and subgroup levels regarding the bacterial counts. Conclusions: It was observed that a short-term course of 5 days of antibiotic usage is associated with altered microbial abundance and diversity.

Utilization of diverse oligosaccharides for growth by Bifidobacterium and Lactobacillus species and their in vitro co-cultivation characteristics

Various approaches have been used to study the relationship between prebiotics and probiotics. The utilization of different carbohydrates by probiotics depends on the biochemical properties of the enzymes and substrates required by the microbial strain. However, few studies have systematically analyzed the ability of probiotics to utilize different prebiotics. Here, we investigated the effects of prebiotics from different manufacturers on the proliferation of 13 strains of the Lactobacillus group and the genus Bifidobacterium co-cultured in vitro. Inulin, fructose-oligosaccharide (FOS), and galactose-oligosaccharide (GOS) had broad growth-promoting effects. FOS significantly promoted the proliferation of B. longum. When strains from Lactobacillus group and Bifidobacterium were co-cultured, FOS caused each strain to proliferate cooperatively. GOS was effectively used by L. rhamnosus and L. reuteri for energy and growth promotion. L. casei and L. paracasei fully metabolized inulin; these strains performed better than other strains from Lactobacillus group and Bifidobacterium. Media containing a mixture of oligosaccharides had stronger effects on the growth of B. animalis subsp. lactis, L. acidophilus, and L. rhamnosus than media containing single oligosaccharides. Thus, different oligosaccharides had different effects on the growth of probiotics, providing a scientific basis for the use of synbiotics in health and related fields.

Impact of fermented lactobacilli acidophilus and antibiotics topically during the phase of re-epithelization in wound repair of rats.

Objective: To compare the topical effects of lactobacillus acidophilus strain and topical antibiotics during the phase of re-epithelization in wound repair. Study Design: Experimental Longitudinal study. Setting: Al-Tibri Medical College, Isra University Karachi. Period: June to November 2022. Material & Methods: This longitudinal study took place in in which 45 Wistar rats were acquired and divided into three groups, Group A the control group in which normal saline was applied, Group B in which topical Lactobacillus acidophilus was applied, and Group C in which topical neomycin was applied on the 3rd, 7th, and 14th day of the study. A subcutaneous incision was given on all the rats of equal proportion, and on the 3rd, 7th, and 14th day of sampling a histological section was acquired. A micrometer was used to measure the thickness of the dermis and epidermis. Data was analyzed using SPSS, with the p-value set at <0.05. Results: Significant difference was seen in the mean thickness of epidermis when Lactobacillus acidophilus groups was compared with both Group A and C on the 3rd, 7th, and 14th day of the study. Significant difference was also seen in the mean thickness of the dermis when Lactobacillus acidophilus was compared with both Group A and C on the 3rd, 7th, and 14th day of the study. Conclusion: Lactobacillus acidophilus plays a potent rote in repairing dermal tissue as it increased the thickness of dermis and epidermis.

Effects of intake of Lactococcus cremoris subsp. cremoris FC on constipation symptoms and immune system in healthy participants with mild constipation: a double-blind, placebo-controlled study

This study evaluated the effect of Lactococcus cremoris subsp. cremoris FC (FC) on constipation symptoms and the immune system in healthy participants with mild constipation. Eighty-three participants were randomised into four groups with different doses: 50, 75, and 100 mg of freeze-dried FC (test) or corn starch (placebo). Defaecation frequency significantly increased in all test groups compared to the placebo group. Stool appearance and volume were improved considerably within the groups administered 50 mg and 75 mg of FC. The abundances of total bacteria, Bifidobacterium spp., and Lactobacillus group in the faeces showed increasing trends in the test groups. Regarding immunological parameters, the naive T cell counts in the blood were significantly higher at a dose of 75 mg of FC in the test group than in the placebo group. These results suggest that FC intake improves defaecation and some immunological parameters, especially naive T cell counts, in healthy adults.

Resistant starches from dietary pulses modulate the gut metabolome in association with microbiome in a humanized murine model of ageing

Emerging evidence suggests that plant-based fiber-rich diets improve ageing-associated health by fostering a healthier gut microbiome and microbial metabolites. However, such effects and mechanisms of resistant starches from dietary pulses remain underexplored. Herein, we examine the prebiotic effects of dietary pulses-derived resistant starch (RS) on gut metabolome in older (60-week old) mice carrying a human microbiome. Gut metabolome and its association with microbiome are examined after 20-weeks feeding of a western-style diet (control; CTL) fortified (5% w/w) with RS from pinto beans (PTB), black-eyed-peas (BEP), lentils (LEN), chickpeas (CKP), or inulin (INU; reference control). NMR spectroscopy-based untargeted metabolomic analysis yield differential abundance linking phenotypic differences in specific metabolites among different RS groups. LEN and CKP increase butyrate, while INU promotes propionate. Conversely, bile acids and cholesterol are reduced in prebiotic groups along with suppressed choline-to-trimethylamine conversion by LEN and CKP, whereas amino acid metabolism is positively altered. Multi-omics microbiome-metabolome interactions reveal an association of beneficial metabolites with the Lactobacilli group, Bacteroides, Dubosiella, Parasutterella, and Parabacteroides, while harmful metabolites correlate with Butyricimonas, Faecalibaculum, Colidextribacter, Enterococcus, Akkermansia, Odoribacter, and Bilophila. These findings demonstrate the functional effects of pulses-derived RS on gut microbial metabolism and their beneficial physiologic responses in an aged host.

Natural emulsifiers lecithins preserve gut microbiota diversity in relation with specific faecal lipids in high fat-fed mice

Synthetic emulsifiers promote metabolic syndrome and considerably alter gut microbiota. Data is lacking regarding natural emulsifiers like plant lecithins, a polar lipid-rich source of 18:3n-3 PUFA (ALA). For 13 weeks, male Swiss mice were fed ALA-replete semi-synthetic high-fat diet (HFD) including lecithin from rapeseed (RL) or soy, vs 2 HFD-controls devoid of lecithin (ALA-replete; low-ALA), vs Chow. Lecithins did not enhance HFD-induced adiposity nor increased inflammation, did not alter gut barrier markers and caecal bile acids, and contributed to n-3 PUFA status. Lecithins improved gut microbiota diversity. RL (10% in fat) even restored α-diversity similar to Chow, increased Lachnospiraceae NK4A136, Lactobacillus and Ruminococcaceae UCG-014 groups, and decreased Blautia genus bacteria. The abundance of most beneficial lecithin-enhanced bacteria was positively correlated to the amount of faecal polar lipid-bound ALA. These findings show that lecithins can beneficially affect the gut microbiota in association with changes in lipid residues in the distal gut.

Lactic Acid Bacteria from Mangrove Sediment Produce Bacteriocins Active Against Gram-Positive and Negative Bacteria

Mangrove is a unique ecosystem. Only a few studies have explored the presence of lactic acid bacteria and their roles in mangrove ecosystems. From mangrove sediments at Logending Beach in Jawa Tengah (Indonesia), the Lactic Acid Bacteria (LAB) isolates LG-50, LG-107, and LG-114 were discovered. They produce bacteriocins. This study aimed to determine the characteristics of LAB isolates, antimicrobial activity, and physicochemical properties of bacteriocins. LAB isolates were characterized by morphology, physiology, and biochemistry. The production of bacteriocin was performed by salting-out method, followed by testing its antimicrobial activity against pathogenic bacteria. Isolates LG-50, LG-107, and LG-114 are thought to be in the Lactobacillus group. The crude bacteriocin can inhibit the growth of Gram-positive and negative bacteria. The average inhibition zones against Escherichia coli and Staphylococcus aureus were 16.67 mm and 22.17 mm, respectively. The crude bacteriocin tested positive for ninhydrin. It confirmed the crude bacteriocin was a protein and sensitive to the proteolytic enzyme. SDS-PAGE analysis presented the molecular weight of crude bacteriocin was 38 kDa. This present study supports the potential use of bacteriocin in the pharmaceutical and food industries.

Understanding the Effect of Compound Probiotics on the Health of Rabbits and Its Mechanisms Through Metagenomics.

In this study, we investigated the effects of probiotics on growth performance, immunity, intestinal flora, and antioxidant capacity of rabbits. Three hundred New Zealand white rabbits were randomly divided into four groups. Groups A, B, C, and D were the lactobacillus group, compound probiotic group, control group, and antibiotic group, respectively. The results showed compared with the control group, the average weight of groups A, B, and D increased by 14.88%, 12.33%, and 11.97%, respectively. Moreover, the index of immune organs and the IgG and IgM in serum of group B were significantly increased (P < 0.05). Meanwhile, the activities of superoxide dismutase (SOD) in group B and catalase (CAT) in group A were significantly increased (P < 0.05). At week 5, the contents of rabbit cecum were taken for metagenome sequencing, and the results showed probiotics increased the relative abundance of Akkermansia, and decreased the relative abundance of Bacteroides. According to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, we found probiotics could enrich metabolic pathways such as carbohydrates, amino acids, and lipids. According to the Comprehensive Antibiotic Resistance Database (CARD), we found antibiotic resistance ontology (ARO) in cecum mainly included β-lactamases, macrolide 2'-phosphotransferase II, and plasmid-mediated quinolone resistance protein. Among them, there were 1964, 2105, and 1982 types of ARO in group B, group D, and groups A and C, respectively. These results showed probiotics played a beneficial role in maintaining or enhancing the health and growth of rabbits and could replace antibiotics under certain feeding conditions.

Gut Microbiota and Acylcarnitine Metabolites Connect the Beneficial Association between Estrogen and Lipid Metabolism Disorders in Ovariectomized Mice.

Decreased estrogen level is one of the main causes of lipid metabolism disorders and coronary heart disease in women after menopause. Exogenous estradiol benzoate is effective to some extent in alleviating lipid metabolism disorders caused by estrogen deficiency. However, the role of gut microbes in the regulation process is not yet appreciated. The objective of this study was to investigate the effects of estradiol benzoate supplementation on lipid metabolism, gut microbiota, and metabolites in ovariectomized (OVX) mice and to reveal the importance of gut microbes and metabolites in the regulation of lipid metabolism disorders. This study found that high doses of estradiol benzoate supplementation effectively attenuated fat accumulation in OVX mice. There was a significant increase in the expression of genes enriched in hepatic cholesterol metabolism and a concomitant decrease in the expression of genes enriched in unsaturated fatty acid metabolism pathways. Further screening of the gut for characteristic metabolites associated with improved lipid metabolism revealed that estradiol benzoate supplementation influenced major subsets of acylcarnitine metabolites. Ovariectomy significantly increased the abundance of characteristic microbes that are significantly negatively associated with acylcarnitine synthesis, such as Lactobacillus and Eubacterium ruminantium group bacteria, while estradiol benzoate supplementation significantly increased the abundance of characteristic microbes that are significantly positively associated with acylcarnitine synthesis, such as Ileibacterium and Bifidobacterium spp. The use of pseudosterile mice with gut microbial deficiency greatly facilitated the synthesis of acylcarnitine due to estradiol benzoate supplementation and also alleviated lipid metabolism disorders to a greater extent in OVX mice. IMPORTANCE Our findings establish a role for gut microbes in the progression of estrogen deficiency-induced lipid metabolism disorders and reveal key target bacteria that may have the potential to regulate acylcarnitine synthesis. These findings suggest a possible route for the use of microbes or acylcarnitine to regulate disorders of lipid metabolism induced by estrogen deficiency.

Promotion of hair growth by Lactobacillus and fermented traditional Korean berry in C57BL/6 mice

Hair loss is the state of losing hair from the scalp or entire body when new hair does not replace the hair that has fallen out. Currently, remedies such as oral finasteride and topical minoxidil are commonly used. However, these drugs may have temporary effects and cause side effects such as depression, irregular heartbeat and weight gain when used long term. Therefore, an alternative hair growth promoting agent is needed. The hair follicle undergoes anagen, catagen, and telogen phase which affect hair growth, and this hair-growth cycle is regulated by growth factors, cytokines, and hormones. Some studies reported that the gut microbiome (GM) regulates the transition between the hair growth cycle by producing hair growth-related factors and nutrients. Also, inflammation by GM affects the cascade of the inflammation in the hair follicle, which may lead to hair growth arrest. Previous studies showed strains of Lactobacillus (LAB) have anti-oxidative and anti-inflammatory effects in an HT-29 human colon epithelial cell model and an HaCaT human keratinocyte cell model. Also, traditional Korean berry has anti-inflammatory effects in an HT-29 model. Thus, LAB and fermented traditional Korean berry by LAB (FB) may promote hair growth by regulating gut microbiome. This study investigated the effect of LAB and FB on hair growth in vivo. Six-week-old male C57BL/6 mice were used for evaluating the hair growth-promoting effects of the LAB and FB. The dorsal hair of mice was depilated, and they were orally treated with LAB at 1010 CFU/kg and FB at 250mg/kg daily for 22 days. As a result, the hair re-growth rate was significantly increased in LAB and FB groups compared with the control group. In the histological analysis of skin, FB increased the number of hair follicle and subcutaneous fat layer thickness. The mRNA expression levels of hair growth-related growth factors such as VEGF and IGF-1 are significantly increased in colon and skin. Moreover, Treatment of LAB and FB changed the composition of the microbiome and short chain fatty acids in mice. Altogether, LAB and FB supplementation may promote hair growth by regulating growth factors and altering gut microbiota compositions. In conclusion, strain of LAB and FB are potential novel approaches for hair growth promotion. This work was supported by Korea Testing Laboratory This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.