Probiotic Properties of Lactobacilli Isolated from Thai Traditional Food

Abstract

Certain properties relevant to probiotic action, e.g. resistance to acid, bile tolerance, adhesive properties, antibacterial activity, and antibiotic susceptibility were investigated of lactobacilli isolated from four kinds of Thai traditional fermented foods. Media of pH = 2.0-7.0 and bile salt concentrations of 0.3-1.0%were used as stress conditions. The adhesive properties were assessed by determination of bacterial hydrophobicity. Antibacterial activity of the probiotic lactobacilli was determined by means of the spot-on-lawn method. Among 563 isolates, only 3 strains (two from fermented pork and one from fermented tea leaves) showed extremely high survival rates under stress caused by acid or bile salts. The identification by PCR techniques revealed that these three strains were Lactobacillus fermentum. The strains from fermented pork showed higher adhesive potential than those from fermented tea leaves. The three strains inhibited test pathogenic bacteria to different extents. They were sensitive to chloramphenicol, quinupristin, erythromycin, kanamycin linezolid, rifampicin, streptomycin, and tetracycline but resistant to ciprofloxacin and vancomycin.

Isolation and Characterization of Lactic Acid Bacteria Strains from Raw Camel Milk for Potential Use in the Production of Yogurt

“…The strain SCC1-24 presents no inhibition against Micrococcus luteus. The difference in inhibition potential among the selected strains was considered to be due to the different intrinsic factors induced by different food origins [53]. The inhibitory action of LAB bacteria is mainly due to the accumulation of main primary metabolites such as lactic and acetic acids, ethanol and carbon dioxide.…”

Obtención, caracterización y evaluación de dos preparados candidatos a probióticos desarrollados con residuos agroindustriales

“…Los cultivos mixtos desarrollados en subproductos de la agroindustria y su capacidad antagónica a los microorganismos patógenos (Tabla 4), fue debido a la acción de las bacterias ácido lácticas, mediante la producción de ácidos orgánicos débiles principalmente el ácido láctico, competen por los nutrientes, capacidad de sobrevivir en condiciones anaerobias ambiente inhostil para las bacterias aeróbicas (27). Al mismo tiempo, son capaces de producir ácido láctico, peróxido de hidrógeno, posiblemente bacteriocinas, las cuales son características del metabolismo de las bacterias acido lácticas (13,24).…”

“…Mixed cultures developed in agroindustry waste and their antagonistic capacity to the pathogen microorganisms (Table 4), was owed to the action of the lactic-acid bacteria, through the production of weak acids of small chain, mainly the lactic acid, competing for the nutrients, their capacity to survive in anaerobic conditions, non-hostile environment for aerobic bacteria (27). At the same time, there are capable of produce lactic acid, hydrogen peroxide, possibly bacteriocins, which are characteristics of the metabolism of lactic-acid bacteria (13,24).…”

“…Lo anterior permite predecir que al uso de cultivos mixtos desarrollados a partir de bacterias ácido lácticas y levaduras seleccionadas en esta investigación, sería recomendable realizar estudios "in vivo" para evidenciar su uso como alternativa a antibióticos de uso veterinario (8,13). La sensibilidad de las cepas podría depender de la resistencia a ciertas concentraciones de antibióticos debido a la presencia de algunos plásmidos, o a propiedades particulares de la pared y membrana de estos microorganismos, por un mecanismo inespecífico que actúa frente a diferentes antibióticos y por las modificaciones en el gen que codifica, haciéndolos impermeables (10,21,27).…”

Evaluation of Probitoic Potential of Lactobacillus Strains From Fermented Foods and Feaces of Infants

“…The antibiotic resistance of pathogenic bacteria is an increasing medical problem [8], and raises the question of antibiotic resistance among desired probiotic strains. Therefore, the antibiotic susceptibility test should be incorporated for the safety assessment of the desired property of the promising probiotic Lactobacillus [9]. Although Lactobacillus shows a high impact on effective protection to human health, there is obvious evidence that Lactobacillus from different origins possess probiotic properties at different levels [10].…”