Variation Of Nutrients And Antioxidant Activity Of Oil-Tea Camellia(Camellia Oleifera Abel.) Seed In Maturation

To guide the harvest time of Camellia oleofera fruit and evaluate the quality of Camellia oleofera oil, Camellia oleofera seeds in Jiande from September7to October26of2012were selected as the study samples. Oil fat synthesis process and nutrients variation of camellia seed in maturation as well as the process of scavenging activity of reactive oxygen of endogenous antioxidants in camellia seed were studied. Results were as follows:(1) In maturation process of camellia seed, acid value(AV) and peroxide value(PV) were under an overall downward trend, and the correlation coefficient between AV and PV was0.805; dry seed rate and dry kernel oil rate were rising while fresh seed moisture content decreased rapidly; fresh seed kernel rate increased slightly, but change of fresh seed rate was not obvient; the rate of dry kernel oil with fresh seed ratio, dry seed rate and fresh seed moisture contents were correlated significantly, the coefficients were0.597,0.930and-0.930, respectively.(2) Fat was accumulating and content of unsaturated fatty acid was increasing up to82.86%with maturation of camellia seed; oleic acid was negatively correlated with contents of palmitic acid, palmitic acid, linoleic acid, linolenic acid and arachidonic acid significantly, while positively correlated with stearic acid content significantly; soluble starch and soluble protein content showed a rising trend; total soluble sugar content increased in the early growth, and declined rapidly in late maturation; fat accumulation of camellia seed was negatively correlated with total soluble sugar with the correlation coefficient of-0.289, positively correlated with soluble starch and soluble protein with the correlation coefficients of0.836and0.703, respectively.(3) A-tocopherol content was growing up to0.15mg·g-1and then kept stable; contents of squalene and β-sitosterol increased first and then declined in maturation period; polyphenol content was in an upward trend up to14.225mg·g-1. In camellia seed maturation process, superoxide anion radicals increased, its content changes correlated with antioxidant enzymes including SOD, POD and CAT significantly with the correlation coefficients of0.529,0.621and0.477; APX content changed related to SOD, POD and CAT significantly with the correlation coefficients of0.480,0.496and0.702; acid value and peroxide value were associated with content of antioxidant enzymes CAT and APX significantly, correlated with antioxidant VE and polyphenols negatively.(4) By comparison of soxhlet extraction and ultrasonic extraction of tea saponin, conclusions were as follows:using ultrasonic extraction method to extract tea saponin was better under laboratory conditions. Contents of camellia tea saponin was highest in tea seed kernels, second in fruit shell the and the least in seed shell. Tea saponin content in various parts of camellia fruit increased first then declined in maturation, reaching a peak then stayed stable. Saponin content of camellia seed kernels, fruit shell and seed shell was up to15.85%,9.66%and4.32%, respectively.