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Probiotics research on lactic acid bacteria (LAB) continues to be paramount in the development of nutraceutical or functional foods. In this study, 47 selected Philippine plants having nutritional (edible such as vegetables) and/or medicinal values (therapeutic), were collected, from which selected fruit and leaves were subjected to LAB enumeration. Among these, 46.7% plant leaves reported to have strong antimicrobial property resulted in non-isolation of LAB while edible plant leaves with less or no antimicrobial properties generally gave numerous LAB isolates. Isolates coming from ripened guava (Psidium guajava L.), lobo-lobohan or cape gooseberry (Physalis peruviana L.) fruit, parsley (Petroselinum crispum), pandan (Pandanus amaryllifolius), spinach (Spinacea oleracea), leek (Allium ampeloprasum var. porrum) and niyog-niyogan (Quisqualis indica L.) leaves were identified through partial 16S rRNA analysis and tested for probiotic properties. Overall, Streptococcus luteciae Lb17 from ripe gooseberry fruit exhibited the highest antimicrobial activities against Staphylococcus aureus BIOTECH 1526, Escherichia coli O157: H7 BIOTECH 10311 and Bacillus cereus BIOTECH 1509. On the other hand, Enterococcus hirae (H and S63) from stevia were susceptible to streptomycin at minimum inhibitory concentration or MIC of 128 ug/mL). Lactobacillus plantarum F39 and all the other strains tested, meanwhile, was susceptible to ampicillin at MIC of 2 ug/mL and 0.125 ug/mL. Results were lower or equal to the established cut off value indicating the absence of antibiotic resistance genes among the identified strains, except for Pediococcus (Par5 and NN39) which showed resistance against streptomycin. Further investigation is needed to rule out the possibility of transfer of antibiotic resistance to pathogens present in the gut. All isolates tested were able to survive at artificial gastric juice (pH 2), revived at the simulated intestinal fluid (pH 8), and exhibited minimal titratable acidity and diacetyl production. For genetic screening of plantaricin genes, F39 possesses both plantaricin EF and plantaricin J, while Lactobacillus fermentum F36 has plantaricin EF. Both isolates were subjected to DNA fingerprinting. Such findings on the local isolates’ probiotic properties suggest the possibility of incorporating them into different plant-based probiotic foods. |
