Non-traditional sources for isolation of lactic acid bacteria

Abstract

In recent years there has been increasing interest in lactic acid bacteria isolated from non-dairy products, due to their diverse metabolic profile, unique flavorforming activities, and potential for use as starters or starter adjuncts for the dairy industry. Screening of 400 microbial isolates obtained from the herbs Geranium sanguineum L., Hypericum perforatum L., and Panax ginseng C.A. Meyer was performed, and 64 isolates were selected based on milk coagulation and gas formation ability and non-specific odour. Using tests involving multiple transfer and growth in selective and differential media, 258 single colonies were isolated, of which 98 were affiliated with the lactic acid bacteria group. These bacteria are homofermentative cocci and rods with a wide pH (5.0-9.6) and temperature range (15-45°C), high salt tolerance (3.0-10.0 % NaCl), and high acid-producing activity (3.50-12.00 g/L). With the use of genotypebased methods, the plant isolates were identified at the species level as Enterococcus faecium, Streptococcus thermophilus and Lactobacillus rhamnosus.

Traditional Balkan fermented milk products

“…In recent years, in order to increase dairy products value, the interest in alternative sources for isolation of LAB is raising up, because they are carriers of greater metabolic activities and a variety of flavor-forming substances [89]. There are evidences that LAB, isolated from nondairy products have better biochemical and physiological characteristics (production of lactic acid, temperature and pH growth range, and halotolerance) compared with the LAB of milk origin [90][91][92][93][94][95][96]. This is a prerequisite for including them in the future in starter communities or as adjunct cultures for the production of new fermented dairy products, with improved nutrition and health effects.…”

Culture Dependent and Independent Analysis of Potential Probiotic Bacterial Genera and Species Present in the Phyllosphere of Raw Eaten Produce

“…From the cultivated isolates, one L. plantarum and one Leuconostoc lactis isolate were present, both being recognized as probiotic bacteria [55,57,58,72,85]. Enterococci are LAB that are naturally associated with the gastrointestinal tract of humans and animals, but plant-associated E. faecium isolates have been found previously [64,86]. Several E. faecium strains possess strong probiotic activity [65,67], and since two of the five investigated phyllospheres harbored this species, a possible influence on the intestinal flora of the consumer is assumable.…”

Biosorption of silver cations onto Lactococcus lactis and Lactobacillus casei isolated from dairy products

“…Other sources of lactobacteria are fecal samples, soil and plants [25, 26]. In particular, samples of human and animal milk are habitats rich in nutrients and they are often used for isolation of a diverse spectrum of LAB [27–29].…”