Bamboo shoots may offer prebiotic potential

Newly identified polysaccharides from bamboo shoots have the potential to be used as functional ingredients by industry, say researchers.

New research from China has identified two new water-soluble polysaccharide fractions in bamboo shoots that may have prebiotic properties.

“Recently, great attentions have been paid to develop functional foods from the bamboo shoots based on its edibility and application in traditional Chinese and Japanese medicine,” noted the research team – led by Shudong He from Hefei University of Technology in China. 

Writing in Carbohydrate Polymers, the study reports on the isolation and characterization of two novel polysaccharides, which were then tested for their potential probiotic activity – finding that they both aided the growth of probiotic bacterial strains.

Compared to a blank control and a reference of fructooligosaccharide, the Chinese team found that the two water-soluble polysaccharides from bamboo shoots (referred to as WBP-1 and WBP-2) “significantly increased the numbers of Bifidobacterium adolescentis and Bifidobacterium bifidum (…) which contributed to the production of organic acids, suggesting that the polysaccharides have potential prebiotic properties.”

“Therefore, the novel polysaccharides from bamboo shoots might represent the natural functional components to be employed in the food industry,” the authors wrote – adding that further research in humans is now needed to test the relationship between the structure of the polysaccharides and the functional mechanism.

Bamboo research

The Chinese team noted that the bamboo shoots used in the current study (Phyllostachys praecox) is a relatively rare bamboo species in China, that is mainly cultivated in the Anhui, Jiangsu and Zhejiang provinces.

Commonly called ‘early bamboo’, because its fresh shoots are always the first ones to appear in spring, P. praecox plantations in China have increased by around thousand-fold in the last few decades, said the team – who noted that the popular taste of the shoots has attracted significant economic attention.

“Nevertheless, there is no specific reports on the extraction and activities of polysaccharides from P. praecoxshoots,” they said.

Prebiotic potential

The new study set out to identify and optimize the parameters of extraction for the water-soluble polysaccharides based on the single-factor experiments, before the structural features and prebiotic potential of WBP1 and WBP2 were determined.

The team extracted the two polysaccharides from the bamboo shoots using hot-water extraction followed by anion exchange chromatography and size exclusion chromatography. 

“Both the polysaccharides fractions were identified as heteropolysaccharides-protein complexes composed of 15 kinds of common amino acids in protein part and rhamnose, arabinose, xylose, mannose, glucose and galactose in different molar ratios in polysaccharide part,” wrote the authors  - who also revealed a dose-dependent relationship between the bamboo polymers and the growth of two probiotic strains.

Indeed, WBP-1 and WBP-2 were found to significantly, and dose-dependently, increase the numbers of B. adolescentis and B. bifidum after 48 hours incubation.

Source: Carbohydrate Polymers

Volume 151, Pages 295–304, doi: 10.1016/j.carbpol.2016.05.072

“Isolation and prebiotic activity of water-soluble polysaccharides fractions from the bamboo shoots (Phyllostachys praecox)”

Authors: Shudong He, et al