In vitro fermentation of prebiotics by Lactobacillus plantarum CFR 2194: selectivity, viability and effect of metabolites on β-glucuronidase activity

Irinotecan-gut microbiota interactions and the capability of probiotics to mitigate Irinotecan-associated toxicity

BACKGROUND

Irinotecan is a chemotherapeutic agent used to treat a variety of tumors, including colorectal cancer (CRC). In the intestine, it is transformed into SN-38 by gut microbial enzymes, which is responsible for its toxicity during excretion.

OBJECTIVE

Our study highlights the impact of Irinotecan on gut microbiota composition and the role of probiotics in limiting Irinotecan-associated diarrhea and suppressing gut bacterial β-glucuronidase enzymes.

MATERIAL AND METHODS

To investigate the effect of Irinotecan on the gut microbiota composition, we applied 16S rRNA gene sequencing in three groups of stool samples from healthy individuals, colon cancer, and Irinotecan treated patients (n = 5/group). Furthermore, three Lactobacillus spp.; Lactiplantibacillus plantarum (L. plantarum), Lactobacillus acidophilus (L. acidophilus), Lacticaseibacillus rhamnosus (L. rhamnosus) were used in a single and mixed form to in-vitro explore the effect of probiotics on the expression of β-glucuronidase gene from E. coli. Also, probiotics were introduced in single and mixed forms in groups of mice before the administration of Irinotecan, and their protective effects were explored by assessing the level of reactive oxidative species (ROS) as well as studying the concomitant intestinal inflammation and apoptosis.

RESULTS

The gut microbiota was disturbed in individuals with colon cancer and after Irinotecan treatment. In the healthy group, Firmicutes were more abundant than Bacteriodetes, which was the opposite in the case of colon-cancer or Irinotecan treated groups. Actinobacteria and Verrucomicrobia were markedly present within the healthy group, while Cyanobacteria were noted in colon-cancer and the Irinotecan-treated groups. Enterobacteriaceae and genus Dialister were more abundant in the colon-cancer group than in other groups. The abundance of Veillonella, Clostridium, Butryicicoccus, and Prevotella were increased in Irinotecan-treated groups compared to other groups. Using Lactobacillus spp. mixture in mice models significantly relieved Irinotecan-induced diarrhea through the reduction of both β-glucuronidase expression and ROS, in addition to guarding gut epithelium against microbial dysbiosis and proliferative crypt injury.

CONCLUSIONS

Irinotecan-based chemotherapy altered intestinal microbiota. The gut microbiota participates greatly in determining both the efficacy and toxicity of chemotherapies, of which the toxicity of Irinotecan is caused by the bacterial ß-glucuronidase enzymes. The gut microbiota can now be aimed and modulated to promote efficacy and decrease the toxicity of chemotherapeutics. The used probiotic regimen in this study lowered mucositis, oxidative stress, cellular inflammation, and apoptotic cascade induction of Irinotecan.

Lactiplantibacillus plantarum CCMA 0743 and Lacticaseibacillus paracasei subsp. paracasei LBC-81 metabolism during the single and mixed fermentation of tropical fruit juices

Fruit juices have shown promising results as new probiotic carriers. This study aimed to evaluate acerola, jelly palm, and passion fruit juices as substrates for fermentation using Lactiplantibacillus plantarum CCMA 0743 and Lacticaseibacillus paracasei LBC-81 in single and mixed cultures. First, the juices were evaluated as substrate and selected based on bacterial growth performance during fermentation. Afterward, the impact of fermentation on sugars, organic acids, and bioactive compounds was also appraised. Phytochemical modification of three different juices fermented by lactic acid bacteria at 37 °C/24 h was evaluated. After 18 h of fermentation, passion fruit juice showed higher cell viable counts of single and mixed L. plantarum CCMA 0743 culture, above 9.00 Log CFU/mL, and pH between 4.07 and 4.10. Sugars consumption and organic acid production were influenced by juice composition and culture used. The mixed culture reduced the total sugars in the passion fruit juice by approximately 53.0% (8.51 g/L). Lactic acid was the main product of the sugars fermentation, with higher concentrations detected in passion fruit juice (8.39-11.23 g/L). Bioactive compounds were analyzed on the selected substrate. The fermentative process reduced antioxidant activity and carotenoid content. However, single L. plantarum CCMA 0743 culture increased the yellow flavonoid content of passion fruit juice by approximately 3.0 µg/mL. L. plantarum CCMA 0743 showed high and suitable cell, viable counts, to claimed probiotic products, increasing bioactive compounds in passion fruit juice. Therefore, this strain and passion fruit substrate showed attractive potential to produce alternative and functional fermented fruit beverages.

The prebiotics (Fructo-oligosaccharides and Xylo-oligosaccharides) modulate the probiotic properties of Lactiplantibacillus and Levilactobacillus strains isolated from traditional fermented olive

This study aimed to examine the influence of two prebiotics, fructo-oligosaccharides (FOS) and xylo-oligosaccharides (XOS), on probiotic properties (resistance to low pH and bile salt, hydrophobicity and auto-aggregation), metabolites production, and antimicrobial activity of probiotic Lactiplantibacillus (L. pentosus S42 and L. plantarum S61) and Levilactobacillus (L. brevis S27) strains isolated from fermented olive. The results demonstrated the ability of strains to ferment XOS more than FOS as a sole carbon source, resulting in pH reduction. The prebiotics (FOS and XOS) significantly increased (p < 0.05) their survival in gastro-intestinal conditions (low pH and 0.3% of bile salts), as well as their hydrophobicity, auto-aggregation and production of proteins, compared to glucose (control). The major organic acids produced by Lactiplantibacillus and Levilactobacillus strains, were oxalic, malic and lactic acids from FOS, XOS and glucose, respectively. No antimicrobial activity was observed from cell-free supernatant (CFS) of Lactiplantibacillus and Levilactobacillus strains obtained from FOS. In the presence of XOS the organic acids, produced by Lactiplantibacillus and Levilactobacillus strains, were more diverse with high contents, and exhibited higher antifungal and antibacterial activities, more than that of FOS and glucose. The combination of L. plantarum S61 and XOS demonstrated the highest inhibition zones ranges of 20.7-22.2 mm against pathogenic bacteria and 29.2-30 mm against yeasts. This combination can be used in production of antifungal preservatives and pharmaceuticals, against pathogenic and spoilage yeasts.

Therapeutic significance of β-glucuronidase activity and its inhibitors: A review

The emergence of disease and dearth of effective pharmacological agents on most therapeutic fronts, constitutes a major threat to global public health and man's existence. Consequently, this has created an exigency in the search for new drugs with improved clinical utility or means of potentiating available ones. To this end, accumulating empirical evidence supports molecular target therapy as a plausible egress and, β-glucuronidase (βGLU) - a lysosomal acid hydrolase responsible for the catalytic deconjugation of β-d-glucuronides has emerged as a viable molecular target for several therapeutic applications. The enzyme's activity level in body fluids is also deemed a potential biomarker for the diagnosis of some pathological conditions. Moreover, due to its role in colon carcinogenesis and certain drug-induced dose-limiting toxicities, the development of potent inhibitors of βGLU in human intestinal microbiota has aroused increased attention over the years. Nevertheless, although our literature survey revealed both natural products and synthetic scaffolds as potential inhibitors of the enzyme, only few of these have found clinical utility, albeit with moderate to poor pharmacokinetic profile. Hence, in this review we present a compendium of exploits in the present millennium directed towards the inhibition of βGLU. The aim is to proffer a platform on which new scaffolds can be modelled for improved βGLU inhibitory potency and the development of new therapeutic agents in consequential.

Inhibitory Effects of Probiotic Lactobacillus on the Growth of Human Colonic Carcinoma Cell Line HT-29

This study was conducted to investigate the inhibitory effect of Lactobacillus cells and supernatants on the growth of the human colon cancer cell line HT-29. Our study results indicated that the PM153 strain exhibits the best adhesion ability and the highest survival in the gastrointestinal tract simulation experiment. Furthermore, after an 8-h co-culture of PM153 and HT-29 cells, the PM153 strain can induce the secretion of nitric oxide from the HT-29 cells. In addition, after the co-culture of the BCRC17010 strain (10⁸ cfu/mL) and HT-29 cells, the Bax/Bcl-2 ratio in the HT-29 cells was 1.19, which showed a significant difference from the other control and LAB groups (p < 0.05), which therefore led to the inference that the BCRC17010 strain exerts a pro-apoptotic effect on the HT-29 cells. Upon co-culture with HT-29 cells for 4, 8 and 12 h, the BCRC14625 strain (10⁸ cfu/mL) demonstrated a significant increase in lactate dehydrogenase (LDH) activity (p < 0.05), causing harm to the HT-29 cell membrane; further, after an 8-h co-culture with the HT-29 cells, it induced the secretion of nitric oxide (NO) from the HT-29 cells. Some lactic acid bacteria (LAB) strains have ability to inhibit the growth of the colorectal cancer cell line HT-29 Bax/Bcl-2 pathway or NO production. In summary, we demonstrated that the BCRC17010 strain, good abilities of adhesion and increased LDH release, was the best probiotic potential for inhibition of HT-29 growth amongst the seven LAB strains tested in vitro.

Preparation, characterization and in vitro antioxidative potential of synbiotic fermented dairy products

The present study, evaluates the antioxidative potential of two synbiotic dairy products viz. synbiotic lassi with honey and whey based synbiotic drink with inulin and orange juice, along with their physicochemical and microbiological activity during storage period. Antioxidative potential of raw ingredients and probiotic cultures used to prepare synbiotic products was also evaluated. Synbiotic lassi with honey was prepared using Streptococcus thermophilus MTCC 5460 (MD2) and Lactobacillus helveticus MTCC 5463 (V3) as probiotics and honey as prebiotic. For preparation of whey based synbiotic drink, Lactobacillus helveticus MTCC 5463 and inulin were used as probiotic and prebiotic, respectively and orange juice was also incorporated. Titratable acidity and pH of both synbiotic products followed a similar pattern of increase or decrease during storage. Furthermore, no major changes were observed in viability of probiotic cultures under storage conditions adapted. The hydroxyl radical scavenging activity of synbiotic lassi with honey was found to significantly decrease from 107.76 to 79.41 % at the end of storage whereas, the activity of whey based synbiotic drink was 100.32 % which declined sharply to 79.21 % on 7th day but further increased to 102.59 % on 14th day. The DPPH (α, α-Diphenyl-β-Picrylhydrazyl) radical scavenging activity of freshly prepared synbiotic lassi with honey was 28.43 % which decreased to 23.03 % on 7th day while for whey based synbiotic drink decreased from 26.85 % (0 day) to 17.12 % (7th day) and continued to decline. Moreover, probiotic strains used for synbiotic preparation also demonstrated good antioxidative activity.

Metabolism of Fructooligosaccharides in Lactobacillus plantarum ST-III via Differential Gene Transcription and Alteration of Cell Membrane Fluidity

Although fructooligosaccharides (FOS) can selectively stimulate the growth and activity of probiotics and beneficially modulate the balance of intestinal microbiota, knowledge of the molecular mechanism for FOS metabolism by probiotics is still limited. Here a combined transcriptomic and physiological approach was used to survey the global alterations that occurred during the logarithmic growth of Lactobacillus plantarum ST-III using FOS or glucose as the sole carbon source. A total of 363 genes were differentially transcribed; in particular, two gene clusters were induced by FOS. Gene inactivation revealed that both of the clusters participated in the metabolism of FOS, which were transported across the membrane by two phosphotransferase systems (PTSs) and were subsequently hydrolyzed by a β-fructofuranosidase (SacA) in the cytoplasm. Combining the measurements of the transcriptome- and membrane-related features, we discovered that the genes involved in the biosynthesis of fatty acids (FAs) were repressed in cells grown on FOS; as a result, the FA profiles were altered by shortening of the carbon chains, after which membrane fluidity increased in response to FOS transport and utilization. Furthermore, incremental production of acetate was observed in both the transcriptomic and the metabolic experiments. Our results provided new insights into gene transcription, the production of metabolites, and membrane alterations that could explain FOS metabolism in L. plantarum.

Three measurable and modifiable enteric microbial biotransformations relevant to cancer prevention and treatment

Interdisciplinary scientific evaluation of the human microbiota has identified three enteric microbial biotransformations of particular relevance for human health and well-being, especially cancer. Two biotransformations are counterproductive; one is productive. First, selective bacteria can reverse beneficial hepatic hydroxylation to produce toxic secondary bile acids, especially deoxycholic acid. Second, numerous bacterial species can reverse hepatic detoxification-in a sense, retoxify hormones and xeonobiotics-by deglucuronidation. Third, numerous enteric bacteria can effect a very positive biotransformation through the production of butyrate, a small chain fatty acid with anti-cancer activity. Each biotransformation is addressed in sequence for its relevance in representative gastrointestinal and extra-intestinal cancers. This is not a complete review of their connection with every type of cancer. The intent is to introduce the reader to clinically relevant microbial biochemistry plus the emerging evidence that links these to both carcinogenesis and treatment. Included is the evidence base to guide counseling for potentially helpful dietary adjustments.

Evaluation and functional characterization of a biosurfactant produced by Lactobacillus plantarum CFR 2194

The study details the investigations on the ability of Lactobacillus plantarum CFR 2194, an isolate from kanjika, a rice-based ayurvedic fermented product, to produce biosurfactant. Surfactant production, as a function of fermentation time, indicates that the maximum production occurred at 72 h under stationary conditions. Isolation, partial purification, and characterization of the biosurfactant produced have been carried out, and Fourier transform infrared spectroscopy (FTIR) spectra demonstrated that biosurfactants were constituted by protein and polysaccharide fractions, i.e., possessed the structure typical of glycoprotein, which is affected by the medium composition and the phase of growth of the biosurfactant-synthesizing strain. Critical micelle concentration (cmc) of the biosurfactant was found to be 6 g l(-1). The emulsification index (EI), emulsification activity (EA), and emulsion stability (ES) values of the biosurfactant have confirmed its emulsification property. Aqueous fractions of the produced biosurfactant exhibited a significant antimicrobial activity against the food-borne pathogenic species: Escherichia coli ATCC 31705, E. coli MTCC 108, Salmonella typhi, Yersinia enterocolitica MTCC 859, and Staphylococcus aureus F 722. More importantly, the biosurfactant from L. plantarum showed antiadhesive property against above food-borne pathogens. The results thus indicate the potential for developing strategies to prevent microbial colonization of food contact surfaces and health-care prosthesis using these biosurfactants.