Chlorella pyrenoidosa Polysaccharides as a Prebiotic to Modulate Gut Microbiota: Physicochemical Properties and Fermentation Characteristics In Vitro.

Kunling Lv,Yonghong Liu,Qingxia Yuan,Haiqiong Ma,Tingting Li,Longyan Zhao,Hong Li,Chenghai Gao,Siyuan Zhang

doi:10.3390/foods11050725

Abstract

This study was conducted to investigate the prebiotic potential of Chlorella pyrenoidosa polysaccharides to provide useful information for developing C. pyrenoidosa as a green healthy food. C. pyrenoidosa polysaccharides were prepared and their physicochemical characteristics were determined. The digestibility and fermentation characteristics of C. pyrenoidosa polysaccharides were evaluated using in vitro models. The results revealed that C. pyrenoidosa polysaccharides were composed of five non-starch polysaccharide fractions with monosaccharide compositions of Man, Rib, Rha, GlcA, Glc, Gal, Xyl and Ara. C. pyrenoidosa polysaccharides could not be degraded under saliva and the gastrointestinal conditions. However, the molecular weight and contents of residual carbohydrates and reducing sugars of C. pyrenoidosa polysaccharides were significantly reduced after fecal fermentation at a moderate speed. Notably, C. pyrenoidosa polysaccharides could remarkably modulate gut microbiota, including the promotion of beneficial bacteria, inhibition of growth of harmful bacteria, and reduction of the ratio of Firmicutes to Bacteroidetes. Intriguingly, C. pyrenoidosa polysaccharides can promote growth of Parabacteroides distasonis and increase short-chain fatty acid contents, thereby probably contributing to the promotion of intestinal health and prevention of diseases. Thus, these results suggested that C. pyrenoidosa polysaccharides had prebiotic functions with different fermentation characteristics compared with conventional prebiotics such as fructooligosaccharide, and they may be a new prebiotic for improving human health.

Highlights

Microalgae have enormous potential to be a food source and a new crop to resolve the world food problem in the 21st century [1]
The high-performance gel permeation chromatography (HPGPC) profile showed that the CPP mainly consisted of five polysaccharide fractions of different molecular weight in a range from 15.3 to 571.8 kDa (Figure 1A)
The non-starch CPP was prepared by the hot water extraction and amylase treatment, which mainly consisted of five polysaccharide fractions of different molecular weight

Summary

Introduction

Microalgae have enormous potential to be a food source and a new crop to resolve the world food problem in the 21st century [1]. One of the most widely cultivated species of microalgae, has attracted considerable attention. It possesses many attractive features, as most microalgae do, such as easy cultivation, a fast growth rate, resistance to adverse growth conditions, rich nutrient value, and a high content of various biologically active substances. There is considerable evidence that Chlorella has a variety of biological activities, such as anti-tumor, anti-oxidant, immunoregulatory, and anti-diabetic activities [2,3]. There are some improvements that will need to be made before Chlorella can become a regular food source. The metabolism and health effects of some macromolecules, such as polysaccharides and proteins from the Chlorella, following oral administration should be deeply evaluated to further supplement and improve the human diet

Methods

Results

Conclusion