Journal of Dairy Research

Research Article

Antioxidant, antihypertensive, and immunomodulatory activities of peptide fractions from fermented skim milk with Lactobacillus delbrueckii ssp. bulgaricus LB340

Bingjun Qiana1a2 c1, Meizi Xinga1, Lei Cuia1, Yun Denga1a2, Yuqun Xua1, Mini Huanga1 and Shaohui Zhanga1a2

a1 Department of Food Science and Engineering, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, P.R. China

a2 SJTU-Bor Luh Food Safety Center, Shanghai Jiao Tong University, Shanghai, 200240, P.R. China

Abstract

The aim of this study was to evaluate the antioxidant, antihypertensive and immunomodulatory characteristics of skim milk fermented with Lactobacillus delbrueckii ssp. bulgaricus LB340. Supernatants obtained from the ferments after centrifugation were subjected to ultrafiltration and yielded four peptidic fractions of 10–5 kDa, 5–3 kDa, 3–1 kDa, and <1·0 kDa. Peptides in 5–3 kDa range exhibited a good antioxidant activity. The peptides (<1·0 k) was applied to Superdex-30 G column fractionation and produced six fractions (F1–6). Fraction F2 presented the highest angiotensin I-converting enzyme inhibition activity with IC50 of 67·71±7·62 mg/ml. Moreover, fraction F6, which displayed a good immunomodulatory activity, had a positive effect on murine spleen lymphocyte proliferation with Stimulation Index of 0·729±0·123. The present data showed the potential of the milk fermented with Lactobacillus delbrueckii ssp. bulgaricus LB340 as a functional food, however, further research is needed to evaluate the biofunctional activity of this fermentation product in vivo using model animal.

(Received March 29 2010)

(Accepted September 15 2010)

(Online publication January 10 2011)

Correspondence:

c1 For correspondence; e-mail: bjqianfd@sjtu.edu.cn

Footnotes

† These authors contribute to this work equally