Bifidobacteria belongs to the so-called beneficial intestinal flora. Before attempting to raise their intestinal levels to improve the health status of the host, it is importance to know about physiological variations in the Bifidobacterial colonization of the human intestine. Birth process influenced the diversity of Bifidobacteria in infant feces. This research was intended to isolate and characterize Bifidobacterium spp. as well to evaluate their presence in the feces of infants who were born by mode of normal, caesarean and premature. The research was conducted by survey method and data were analyzed with descriptive analysis. Bifidobacterium character was observed include colony and cell morphology. The biochemical test included catalase, oxidase, indole, Voges-Proskauer, different pH growth, and resistance to lysozyme. Bifidobacterium metabolites obtained tested its bacterial activity to Salmonella typhimurium and Escherichia coli. The result of this research showed that 35 isolates are suspected Bifidobacterium group and after API 20 A test showed 17 isolates are rally genera of Bifidobacterium spp.and all isolates come from infant feces with caesar and premature delivery. These isolates inhibited the growth of S. typhimurium and E. coli with different inhibitory capabilities. This finding is very important for science and medical point of view and could be developed with further research.

Abstract. Kusharyati DF, Pramono H, Ryandini D, Manshur TA, Dewi MA, Khatimah K, Rovik A. 2020. Bifidobacterium from infant stool: the diversity and potential screening. Biodiversitas 21: 2506-2513. Bifidobacteria spp. are a group of Lactic Acid Bacteria commonly found in the gastrointestinal tract of adults and infants. LAB are known as probiotics and have many health benefits. This research aimed to isolate Bifidobacteria from infant stool, identify, explore their diversity, and screen their potential as probiotics. Stool samples were collected from 3 healthy infants in Banyumas Regency. The potential screening included lysozyme resistance, antimicrobial activity, and exopolysaccharide production. A total of 7 Bifidobacterium species were isolated from infant stool: B. catenulatum, B. minimum, B. indicum, B. dentium, B. asteroides, B. galicum, and B. coerinum. B. indicum isolates (Bb3F and Bb1B) had the greatest inhibition activity against Escherichia coli and Candida albicans with 10.80 and 9.70 mm, respectively. Bifidobacteria isolates were resistant to lysozyme from egg whites up to 200 µg.mL-1. B. catenulatum Bb1A isolate had the highest yield of exopolysaccharide production with 74 mg.L-1. Among them, three Bifidobacterium strains (Bb1B, Bb2A, and Bb2E) were considered potentially as probiotics.

Isolation of actinomycetes has been done from mangrove soil sample of Segara Anakan Cilacap. This research aimed to know the potency of actinomycetes as an antifungal producer, and to measure antifungal activity produced by actinomycetes based on diameter zone inhibition and to know the characteristic of the bioactive compound with Thin Layer Chromatography method. The result of the study has been isolated 24 actinomycetes isolates, 15 of them had potential as an antifungal producer, which inhibited the growth of Candida albicans. Period of fermentation significantly affected to the activity of the antifungal compound. The highest inhibitory zone was formed by an antifungal extract from actinomycetes C with a range zone 19.7 mm in length at 14th days fermentation, which was extracted with ethyl acetate solvent (1: 1 v / v). The characteristic of a bioactive compound of the actinomycetes C ha s a Rf value 0.5 in the solvent n-butanol, acetic acid and water (3: 2: 1 v / v / v).

Lactic acid bacteria (LAB) are used in the making of soyghurt such Lactobacillus bulgaricus, Streptococcus thermophillus, and Bifidobacterium sp. with optimum growth temperature at 36° -37° C and the incubation time ranges from 1-2 days. LAB is known able to produce bacteriocins that can inhibit pathogenic bacteria in the digestive tract such as Bacillus cereus. The purpose of this study was to determine the ratio of LAB on soyghurt on inhibition of B. cereus, determine the length of incubation soyghurt with the addition of Bifidobacterium sp. on the growth of B. cereus, and determine the effect of LAB concentrations and longer incubation at soyghurt on the growth of B. cereus. The results show a comparison of LAB (L. bulgaricus : S. thermophillus : Bifidobacterium sp.) 1: 1: 1 (K1) on soyghurt able to inhibit B. cereus. Long incubation soyghurt with the addition of Bifidobacterium sp. optimal at 24 hour on the growth of B. cereus. LAB concentration with a long incubation at soyghurt not able to increase the growth inhibitory B.cereus.

The meat and fisheries products have high nutritional content which is highly ideal for bacterial growth. Lactic Acid Bacteria (LAB) have several potential advantages as a bio-preservative agent in the food industry because they produce antimicrobial substances against pathogenic bacteria e.g. bacteriocin. Our previous study has succeeded in isolating and characterizing LAB from the mangrove sediments of Logending Beach, Kebumen. This present study aimed to determine the activity of bacteriocinogenic-LAB against food-borne pathogens and their potential for fisheries product preservation. The study consisted of five serial stages, as follows: screening of LAB isolates, cell-free supernatant production and its inhibition activity, extraction of partially purified bacteriocin, bacteriocin confirmation against proteolytic enzymes, and in-vitro test of partially-purified bacteriocin against Listeria monocytogenes, Shigella flexneri, and Salmonella typhi. A total of 25 out of 99 isolates were able to grow on MRSA+1% CaCO3 medium. Initial screening showed that the cell-free supernatant of 14 LAB isolates was able to inhibit the growth of S. thypi, S. flexneri, and L. monocytogenes. There was an increased inhibitory activity of partially purified bacteriocin when compared with the cell-free supernatant which was statistically different (p<0.01). It indicated that the purification was successfully performed. Bacteriocin expressed a lower inhibition against S. typhi than L. monocytogenes and S. flexneri. The ANOVA test showed that each indicator pathogenic-bacterium expresses a very significant sensitivity to the partially purified bacteriocin.