EFFECT OF DIFFERENT CARBON SOURCES ON GROWTH AND FERULOYL ESTERASE ACTIVITY OF PROBIOTIC LACTOBACILLI

ABEIJON MUKDSI, C., RUSSO, M., GAUFFIN CANO, P., PEREZ CHAIA, A. MEDINA R.

Campinas, San Pablo

Simposio; 12 Simposio Latinoamericano de Ciencias de los alimentos; 2017

Feruloyl esterases (FE) areenzymes that hydrolyze hydroxycinnamate esters naturally present in vegetable foods, releasing hydroxycinnamic acids (HA) that can be absorbed at the gut.HA, such as ferulic acid (FA), have antioxidant properties in vitro and invivo. Thus, the use of lactic acid bacteria with FE activity represents aninnovative proposal in the field of functional foods and dietary supplements.Our aim was to evaluate the effect of different carbon sources on growth and FEactivity of probiotic lactobacilli strains. Three FE producing-strains of foodand intestinal origin were used: Lactobacillus fermentum (Lf) CRL1446, L.johnsonii (Lj) CRL1231 and L. acidophilus (La) CRL1014. Cell growth (O.D. 560nm) in a minimal culture medium supplemented with different carbon sources(0.5% w/v glucose, xylose, arabinose, fructose, ethyl ferulate, chlorogenicacid) was evaluated. Minimal medium without supplementation was used ascontrol. FE activity was determined by incubation of cell suspensions (obtainedfrom 6 h cultures) in PBS pH 7 containing 1 mM methyl ferulate as substrate.Released FA was quantified by HPLC. All strains grew in the different mediaassayed, remaining in exponential phase until 6 h. In general, the highestgrowth rates were observed in media containing glucose and fructose. Comparedto control, no differences were detected in presence of hydroxycinnamates(ethyl ferulate or chlorogenic acid). FE activity of Lf and Lj was induced byethyl ferulate (10% and 80%, respectively), whereas in La it was stimulated bychlorogenic acid (37%). Regarding the effect of monosaccharides on FE activity,induction by glucose in Lf and by xylose in La was observed (19% and 15%,respectively). Results show that FE activity is mainly induced byhydroxycinnamates, indicating that the evaluated strains could be used infunctional foods naturally rich in these compounds, contributing to anincreased bioavailability of HA.