Studies On Skin-care Factor In Bamboo Bark

Skin is an important barrier to keep human body from environmental injury. Along with the global tendency of "Back to Nature", more and more attentions have focused on the R&D of "cosmeceuticals",i e., cosmetic functional factors with multiple bioactivities such as anti-free radical, anti-oxidation, anti-irradiation and skin- whiting; moisture-holding; wrinkle-shrinking. Bamboo bark, also called Zhuru, usually refers to the out-layer and next-layer of Bambusa tuldoides Munro, Sinocalamus beecheyana var. pubescens P.F. Li or Phyllostachys nigra (Lodd.) Munrom Var. henonis (Mitf.) Stapf ex Rendle, and all of them belong to the Bambusoideae of Gramineae family. Zhuru is not only a kind of traditional Chinese medicine, but also natural goods that can be used as the raw material of health food approved by the Health Ministry of China. However, the research and investigation on the effective compounds and their pharmacologic activities about Zhuru is rather seldom. The unique works have been conducted by our group including a triterpenoids-rich standard preparation made of Zhuru using by SFE (supercritical CO2 fluid extraction) technology and first created in 2002, so named as EZR2002;, and some publications on its functionality and safety. As SFE method mainly extracted the Zhuru's low-polar position at lower yield, and followed by a staple side-product residue. As we known, the traditional processing course of Zhuru is as follows, dipped in wine, fried drying, and then water decoction. The main medicinal ingredients should be due to polar position in Zhuru. It could be expected that there are abundant effective compounds still remain in the side-product. Therefore, we got another polyphenols-rich standard preparation from the SFE residue, named as EZR2005. This present study is figured out to research the chemistry, functionality and safety of EZR2005 at the view of novel cosmeceuticals. Critical investigating results were summarized as follows:a) EZR2005 consists of 42.1% total polyphenols (including 15.9% total flavonoids), 29.0% total sugar 9.0%(including 9.4% polysaccharides),29.0% triterpenoids, 9.40% protein,9.1% ash and 5.0% moisture; EZR2005 is a potassium-rich preparation (2.6%); The highest content of microelements was manganese, up to 808 mg/kg, followed by zinc and iron, respectively,81.6 and 80.7 mg/kg. It also contains a certain amount of copper and selenium.b) The two compounds were isolated and purified by preparative HPLC and were quantified by HPLC and identified by UV, MS, NMR. The two compounds were p-coumaric acid and tricin. Quality of bamboo leaf extract reference results, the contents of homoorientin, orientin, isovitexin, vitexin, chlorogenic acid,p-coumaric acid, caffeic acid and ferulic acid were quantified by HPLC, in different polar fractions, respectively. At the same time, adenosine has been discovered and quantified in EZR2005, using analytical HPLC.c) Considering the extraction rate and content of adenosine, The optimal extraction condition were confirmed as follows:water extraction (the concentration of ethanol is 0%), ration of solvent to material is 15:1, the extract temperature is 50℃the extract time is 45min. On best experimental conditions, the extraction of adenosine was 96.97±0.25%, the content of adenosine 1.42±0.11 mg/g.d) The antioxidant activities of EZR2005, DE, EA, BU, WT, homoorientin, orientin, isovitexin, vitexin, chlorogenic acid, p-coumaric acid, caffeic acid and ferulic acid were in different antioxidant system has shown excellent anti-free radical activity and reducing power. It has been proved that EZR2005 is a kind of powerful bio-antioxidant.e) EZR2005 skin care functional tests showed that it had significant moisturizing effect, which slightly lower than the positive control, hyaluronic acid, and the significant effect of maintaining flexibility, higher than hyaluronic acid. Melanin was significantly inhibited by EZR2005 on B16 melanoma cells, which was close to the positive control arbutin. EZR2005, DE, EA, BU, WT, and p- coumaric acid in vitro mushroom tyrosinase inhibition were shown and was concentration- dependent manner; The study also shows that EZR2005 on mushrooms inhibitory type of mixed-type inhibition.f) Toxicological evaluation of the EZR2005 showed that the animals skin and eye irritation test results were negative; oral MTD of mice were greater than 20 g/kg body weight, which can be regarded as virtually non-toxic; Mouse micronucleus test, Mouse sperm abnormality test, Ames test results were negative, and no mutagenic effects; 30 d feeding study in rats showed no obvious toxicity of the indicator reaction, the anatomy of the high dose group, and also no abnormal histological pathology changes in rat body weight, food intake, food utilization, blood and blood biochemistry were not affected. The experiment showed no effect on the maximum dose of 10 g/kg body weight. That EZR2005 has a good food security.Research showed that bamboo essence, EZR2005, is a novel cosmeceuticals with multiple bioactivities such as anti-free radical, anti-oxidation, anti-irradiation and skin- whiting; moisture-holding; wrinkle-shrinking. It could be widely used as skin-care factor in cosmetics.