Environmental Factors Affecting the Adhesion of Probiotics to Rice Fiber Fractions

Abstract

The adhesion of pure cultures of probiotics to insoluble dietary fiber (IDF1 and IDF2), soluble dietary fiber (SDF1 and SDF2), and total dietary fiber (TDF1 and TDF2) of two rice varieties (RR1 and RR2) was investigated. Bifidobacteria and Lactobacilli adhered to dietary fiber fractions within 15 to 30 min. A higher percentage of Bifidobacteria (40-70%) adhered to rice fiber than lactobacilli (<40%). Adhesion was not affected by NaCl, or Tween 80 but, was reduced by various sugars and polysaccharides (maltose, moltodextrin, amylopectin, and amylose). The optimal temperature for adhesion was 37°C and live cells are important for adhesion. Adhesion was inhibited by protease and by low pH (pH 3-4). Adhesion was not influenced by proteins or peptides linked with the fiber but involved bacterial cell surface proteins or glycoproteins.

Factors that Affect the Adhesion of Probiotics Bacteria to Resist Rice Starch

“…Our findings may also indicate that the influence of time on the adhesion of bacteria to starch granules seems clear with all samples, for example, Bn1 had the highest percentage of adhesion at the time of 60 m (80%), while we noted a gradual decline with decrease of time (79% at 45m, 71% at 30 m, and 60% at 15 m) , that agreed with previous work by Fernando et al (2011) which; studied attachment of Bifidobacteria and Lactobacilli to dietary fiber fractions within 15 to 60 min., and showed positive relationship between time and attachment percentage of Bifidobacteria and Lactobacilli to rice fiber . Imam and Harry (1991) found the number of Lactobacillus amylovorus cells bound to cornstarch granules increased with time, reaching a maximum of 60 to 75% in 30 min.…”

“…However, the present study did not observe a significant difference in adhesion with an increase in the concentration of starch granules.Our result agreed with Fernando et al (2011), but it Inconsistent with Imam and Harry (1991) who found that; binding of L. amylovorus cells to granules increased proportionally with the concentration of starch present in the incubation mixture.…”

“…High temperatures kill microorganisms, this observation refers that the micro-organisms that live cells are probably to bond with the granular than dead cells. Optimum growth temperature for these microorganisms and body temperature (37 °C) was perfect temperature to adhere (Fernando et al, 2011;Yavuzdurmaz, 2007).…”

“…The adhesion of bacteria depends on numerous factors, including morphological and physiological characteristics, the nature of the substrate and the environment (Fernando et al, 2011).…”

Adhesion of Probiotic Bacteria to Resistant Rice Starch

“…2), that agreed with previous work by Fernando et al (2011) which; studied attachment of Bifidobacteria and Lactobacilli to rice fiber fractions. Hwang et al (2008) have Indicated in their study that adding Tween 80 can increase portability of bacterial adhesion to fiber in animal feed.…”