Journal of Food Processing & Technology

Oxidative related metabolism in Lactobacillus johnsonii and Lactobacillus gasseri species

International Conference on Food Microbiology

August 08-10, 2016 Birmingham, UK

Diamante Maresca, Teresa Zotta and Gianluigi Mauriello

University of Naples Federico II, Italy
Institute of Food Science, Italy

Posters & Accepted Abstracts: J Food Process Technol

Abstract:

Oxygen is considered one of the main factors affecting probiotic bacteria survival due to the induction of lethal oxidative damages. It has been shown that oxidative stress resistance in lactic acid bacteria is strongly dependent on the type of cell metabolism. The shift from fermentative to respiration metabolism (through the addition of heme and menaquinone and in presence of oxygen) was associated with increase in biomass, long term survival and production of antioxidant enzymes. The aim of this work is to investigate the effect of aerobic (AE; presence of oxygen) and respiratory (RS; presence of oxygen, heme end menaquinone) cultivation on the growth kinetic, catalase production and consequent oxygen uptake and oxidative stress response of L. johnsonii and L. gasseri strains isolated from breast-fed babies stools. Moreover, their probiotic features were assessed. For many strains, the AE and RS growth increased pH and biomass production compared to anaerobic cultivation (control). However, only six of them showed to consume oxygen under AE and RS conditions, allowing the selection of oxygen tolerant or respiratory strains. Surprisingly, one strain showed a catalase activity in all growth conditions, while another one showed this activity only in RS condition. Nevertheless, for both strains only RS condition improved their tolerance to oxidative stresses and they showed also proper probiotic features, in term of antimicrobial activity and ability to survive oral-gastrointestinal simulated environment. The exploration of respiratory competent phenotypes may be extremely useful for the development of competitive starter or probiotic cultures.

Biography :

Email: diamante.maresca@unina.it