Effect of traditional leafy vegetables on the growth of lactobacilli and bifidobacteria

Abstract

Traditional leafy vegetables, apart from being a staple in the diet of most of sub-Saharan Africa, are an essential part of traditional medicine and are used daily by traditional healers in the region to treat a wide variety of ailments. In this study, a batch culture technique was used to investigate whether 25 infusions from 22 traditional leafy vegetables stimulated the growth of Lactobacillus bulgaricus, Lactobacillus lactis, Lactobacillus reuteri and Bifidobacterium longum in pure culture. High performance liquid chromatography was used to determine the inulin content of the infusions. Sonchus oleraceus stimulated all four strains and Taraxacum officinale stimulated three strains. In total, 18 plants stimulated at least one of the four probiotic strains. The inulin content of the infusions varied between 2.5% and 3.6%, with Asparagus sprengeri containing the highest percentage. These results indicate that traditional leafy vegetables do stimulate the growth of the selected lactobacilli and bifidobacteria in pure culture and contain inulin. These infusions can now be tested for prebiotic potential using mixed culture systems or human hosts.

• Bifidobacteria
• inulin
• lactobacilli
• Sonchus oleraceus
• Taraxacum officinale

Acknowledgements

We would like to thank the National Research Foundation (NRF) and the South Africa Netherlands research Programme on Alternatives in Development (SANPAD) for funding this project. We would like to thank Dr. Viresh Mohanlall for his assistance with HPLC, and, Mr. Kevin Slaney and Mr. Ntutu Letseka for their assistance with the preparation of this article.