Influence of Some Antibiotics and Essential Oils Used Alone or in Combination on the Vitality of Presumptive Probiotic Lactic acid Bacteria

Aims: The aim of this study was to assess the in vitro antibacterial activity of selected antibiotics and essential oils alone or in combination, on selected presumptive probiotic lactic acid bacteria. Study Design: Experimental studies. Place and Duration of Study: Department of Microbiology of the University of Yaounde I between August 2017 and December 2017 (5 months). Methodology: The chemical composition of five essential oils was determined by gas chromatography coupled with Solid-phase micro extraction. Then the sensitivity of four lactic acid bacteria to the essential oils and four antibiotics was assessed by the well diffusion and macrodilution method. Subsequently, two essential oils active on these bacteria and broad spectrum antibiotics were combined according to the central composite design plan. Results: In general, the chemical composition of essential oils is very diverse, with the example of carvacrol found only in Origanum compactum at 53.24% and thymol in Thymus vulgaris at 56.19% and in Origanum compactum at 15.28%. The antibacterial activity shows that the majority of antibiotics used are active on the bacteria in the study compared to the essential oils where two were active (Origanum compactum and Cymbopogon winterianus). The evaluation of the combinations of essential oils and antibiotics in terms of kinetics has given us three cases: the first case is the one with no acidity or no growth at all; the second is the one where growth is normal; the third where growth is delayed with a more pronounced latency phase. Conclusion: This study suggest that the effect of essential oils and medicinal plant used alone or in combination to antibiotics on the gut microbiota have to be evaluated for validation as well as their toxicity activities before using them for human therapy.

Fecal Microbiome Modulation of Bacterial Communities Associated With the Administration of Probiotic Lactic Acid Bacteria to Feedlot Cattle

Modulation of animal gut microbiota is a prominent function of probiotics to improve the health and performance of livestock. In this study, a large-scale survey to evaluate the effect of lactic acid bacteria probiotics on shaping the fecal bacterial community structure of 126 feedlot cattle during three experimental periods of the fattening cycle (163 days) was conducted. A feedlot industry located in northwestern Argentina was enrolled with cattle fed mixed rations (forage and increasing grain diet). High-throughput sequencing (HTS) of 16S rDNA amplicons was applied to characterize the fecal microbiota and explore its modulation as affected by the administration of five probiotic groups and experimental administration periods. The microbial diversity of fecal samples was significantly affected (p < 0.05) by the administration period compared with probiotic group supplementation. The fecal microbiome of samples was dominated by the Firmicutes (72-98%) and Actinobacteria (0.8-27%) phyla, while a lower abundance of Bacteroidetes (0.08-4.2%) was present. At the family level, probiotics were able to modulate the fecal microbiota with a convergence of Clostridiaceae, Lachnospiraceae, Ruminococcaceae and Bifidobacteriaceae associated with health and growth benefits as core microbiome members. Metabolic functional prediction comparing experimental administration periods showed an enrichment of metabolic pathways related to complex plant-derived polysaccharide digestion as well as amino acids and derivatives during the first 40 days of probiotic supplementation. Genomic-based knowledge on the benefits of autochthonous probiotics on cattle gastrointestinal tract (GIT) microbiota composition and functions will contribute to their selection as antibiotic alternatives for the feedlot industry.

Pengaruh Probiotik Bakteri Asam Laktat dalam Air Minum Terhadap Konversi Pakan Ayam Broiler

This study aimed to determine the effect of probiotics of lactic acid bacteria in drinking water on feed consumption, weight gain and feed conversion ratio of broiler chickens. This research is an experimental research. The experimental animals used in this study were 28 male broiler chickens strain Cobb 700 aged 20 days. P0 was not given the addition of probiotic lactic acid bacteria, P1 was given the addition of probiotic lactic acid bacteria Lactobacillus acidophilus in 1ml/liter drinking water, P2 was given the addition of probiotic lactic acid bacteria Lactobacillus casei in drinking water 1ml/liter, P3 was given the addition of probiotic lactic acid bacteria Lactobacillus fermentum in drinking water 1ml/liter, P4 was given the addition of probiotic lactic acid bacteria Lactobacillus plantarum in drinking water 1ml/liter, P5 was given the addition of probiotic lactic acid bacteria Pediococcus in drinking water 1ml/liter, P6 was given the addition of probiotic mix lactic acid bacteria in drinking water 1ml /liter. Collecting data for the last 1 week by weighing the remaining consumption of feed given and weight gain of broiler chickens. The data obtained were analyzed using the Analysis of Variant (ANOVA) statistical method and continued with Duncan. Based on the results of the calculation of the amount of feed consumption and weight gain in broiler chickens, it showed that the administration of probiotic lactic acid bacteria 1ml/liter of water in broiler chickens could increase body weight gain, reduce feed conversion rates but did not reduce broiler feed consumption (p<0.05).

Double-Barrel Shotgun: Probiotic Lactic Acid Bacteria with Antiviral Properties Modified to Serve as Vaccines

Contrary to the general belief that the sole function of probiotics is to keep intestinal microbiota in a balanced state and stimulate the host’s immune response, several studies have shown that certain strains of lactic acid bacteria (LAB) have direct and/or indirect antiviral properties. LAB can stimulate the innate antiviral immune defence system in their host, produce antiviral peptides, and release metabolites that prevent either viral replication or adhesion to cell surfaces. The SARS-CoV (COVID-19) pandemic shifted the world’s interest towards the development of vaccines against viral infections. It is hypothesised that the adherence of SARS-CoV spike proteins to the surface of Bifidobacterium breve could elicit an immune response in its host and trigger the production of antibodies. The question now remains as to whether probiotic LAB could be genetically modified to synthesize viral antigens and serve as vaccines—this concept and the role that LAB play in viral infection are explored in this review.

Isolation, identification, preservation and determinations of lactic acid bacteria from chicken’s gut content at 26 days old

Chichens’s gastrointestinal (GI) tract presents a large bacterial diversity and can be a beneficial source in order to the isolation of probiotics candidates. In this study, twentythree strains from Lactobacillus genus (one strain of L. acidophilus biotype 1, eight strains of L. acidophilus biotype 3, one of L. crispatus, five of L. fermentum biotype 1, two of L. brevis biotype 2, five of L. salivarius and one strain of L. delbrueckii subsp. delbrueckii) were isolated, cultured, and conserved from ileum and cecum digesta of sixteen chickens, 26 days old, based on their phenotypic characters. The strains confirmation was done by apiwebTM API 50 CHL V.5.1, BioMerieux (France) software, and ABIS online soft. The Lactobacillus strains (106 -108 CFU/g intestinal content) level in the selective medium were determined. The growth of Lactobacillus strains conserved at 4°C (from 48 days to 7 months) and room temperature (from 48 to 90 days) was evaluated. This study showed that chickens can be a stable source for isolating possibly active probiotic lactic acid bacteria (LAB). From Lactobacillus strains isolated and identified, respectively L. fermentum biotype 1 and L. brevis biotype 2 are theoretically suitable for continual testing of probiotic properties.