Plant extracts use plants as raw materials, through physical and chemical extraction and separation processes, to obtain and concentrate one or more active ingredients in plants. Plant extracts can be widely used as materials in the health food industry. There are kinds of plant extracts, and there are more than 300 kinds of industrial extracts, which are classified into glycosides, acids, polyphenols, polysaccharides, terpenoids, flavonoids, alkaloids and so on.
Applications
- Antioxidants: Plant extracts can be applied as antioxidants. For example, the green tea extract is an active ingredient extracted from green tea leaves, and mainly contains tea polyphenols (catechins), caffeine, and aromatic oils. Tea polyphenols in green tea extracts can directly scavenge reactive oxygen free radicals. Tea polyphenols are rich in phenolic hydroxyl groups, which can provide active hydrogen to scavenge free radicals. Therefore, tea polyphenols are free radical inhibitors that supply hydrogen. Tea polyphenols also can inhibit lipid peroxidation, and chelation of metal ions.
- Immunomodulators: Plant extracts can also be used as immunomodulators in health foods. For example, the gynostemma extract is a water extract or an alcohol extract of gynostemma, and the main active ingredient is gypenoside. Gynostemma extract can increase the weight of mice spleen. Gynostemma can also increase the number of white blood cells in peripheral blood and enhance the phagocytic ability of leukocytes, which has an elevated effect on leukopenia caused by CTX. In addition, gynostemma polysaccharides significantly enhance the phagocytosis of peritoneal macrophages.
- Prevention of diseases: Health foods for prevention of some diseases may also contain plant extracts. Ginkgo biloba extract is an active substance extracted from Ginkgo biloba leaves, in which active ingredients are ginkgo flavonoids and ginkgolides. Ginkgo biloba extract is one of the most widely used plant extracts that can prevent cardiovascular and cerebrovascular diseases with multiple targets, and has the functions of scavenging free radicals, anti-oxidation, anti-inflammatory, anti-apoptosis, regulating blood lipids, preventing atherosclerosis, and protecting mitochondria. At the same time, ginkgo biloba extract has few adverse reactions, so it has a good prospect for health food application.
Figure 1. Gynostemma extract.
Figure 2. Ginkgo biloba extract.
References
- WANG W,KANG Q,LIU N,et al. Enhanced dissolution rate andoral bioavailability of Ginkgo biloba extract by preparing solid dis-persion via hot-melt extrusion[J]. Fitoterapia,2015(102):189 - 197.
- HAO PP, JIANG F,CHEN YG,et al. Traditional Chinese med-ication for cardiovascular disease[J]. Nat Rev Cardiol,2015,12(2):115 - 122.
