Effects of tea polysaccharides in tea

Effects of tea polysaccharides in tea

1. What are tea polysaccharides? Sugars, also known as carbohydrates, are the primary products of plant photosynthesis and are the storage nutrients and skeletons of plants. The sugar substances in fresh tea leaves include monosaccharides, oligosaccharides, polysaccharides and a small amount of other sugars. Tea polysaccharides TPS (Tea polysaccharides) are a class of biologically active complex polysaccharides combined with proteins and polyphenols. They can be obtained from various parts of the tea tree, such as leaves, flowers, and fruits, and vary greatly due to different tea varieties and processing techniques. Generally speaking, the coarser and older the raw materials of the tea, the higher the content of tea polysaccharides. Among different types of tea, oolong tea 2-3%> green tea 1-1.5%> black tea 0.5-0.1% (the percentage content refers to the proportion of the weight of the dry tea).

2. Functions of Tea Polysaccharides

(I) Antioxidant function. As a natural polysaccharide, tea polysaccharides have been proven to have good antioxidant activity in scavenging free radicals, resisting reactive oxygen species, protecting cells from oxidative stress damage, and reducing lipid peroxidation. In vitro antioxidant experiments of tea polysaccharides have shown a significant ability to scavenge DPPH free radicals, hydroxyl free radicals, and superoxide free radicals. In animal in vivo experiments, tea polysaccharides can significantly increase the activity of antioxidant enzymes to protect the body from oxidative stress damage.

(II) Hypoglycemic function. The hypoglycemic activity of tea polysaccharides is its most important and most studied function. Tea polysaccharides can inhibit the hydrolysis of starch into glucose and delay the absorption and transport of glucose, thereby achieving the effect of lowering blood sugar. Tea polysaccharides can also reduce insulin resistance and improve insulin secretion and sensitivity. In addition, tea polysaccharides can not only play a role as a drug component, but also as a drug carrier to play a hypoglycemic role. In existing studies, tea polysaccharides can be used as an effective small molecule interfering RNA (siRNA) delivery carrier to regulate the overexpression of key enzymes of sugar metabolism in the liver of diabetic patients, thereby lowering blood sugar levels.

(III) Anti-tumor function. The results of in vitro and animal experiments show that tea polysaccharides have the effect of inhibiting breast cancer, gastric cancer, liver cancer, prostate cancer, colon cancer, cervical cancer and other diseases. This shows that TPS has a universal and extensive anti-cancer effect and anti-tumor activity. The potential mechanism of TPS anti-tumor may be: on the one hand, it can directly inhibit the growth of cancer cells and promote cancer cell apoptosis; on the other hand, it can achieve the purpose of anti-tumor by improving the body's immune ability.

(IV) Regulate the function of intestinal flora. Intestinal flora is not a simple bacterial community. Many studies have confirmed that high-incidence diseases such as obesity and diabetes are closely related to intestinal flora imbalance. Due to the complexity of its structure, tea polysaccharides will not be decomposed by saliva, stomach, and small intestine digestive system, but will reach the large intestine and be used by the intestinal flora in the large intestine, stimulating their growth and synthesizing compounds that are beneficial to the human body. Tea polysaccharides can regulate the composition and abundance of intestinal flora, increase short-chain fatty acids, promote the body's immune response and maintain the normal function of the intestine.

(V) Function of reducing fat and losing weight. Tea polysaccharides also have good lipid-lowering and weight-loss effects. Mice fed a high-fat diet were treated with crude tea polysaccharides. The results showed that tea polysaccharides can effectively reduce the increase of adipose tissue and liver lipid accumulation in mice, and will not suppress the appetite of mice. This shows that tea polysaccharides not only do not suppress appetite, but also can accelerate the excretion of dietary lipids in feces, inhibit lipid accumulation in the liver, and achieve the effect of reducing fat and losing weight.

As a natural active substance, tea polysaccharides have a wide range of application prospects in the field of functional foods and pharmaceuticals due to their excellent biological activity, low toxicity and few side effects. And because the content of tea polysaccharides is higher in coarse and old tea leaves, this also provides an excellent comprehensive utilization method for tea resources such as discarded pruning leaves of tea trees. Tea polysaccharides, as an important functional component of tea trees besides catechins and amino acids, also have great utilization potential.