Study On Quality And Storage Of Guangxi Yam

Objective:Chinese yam is the root tuber of the Dioscorea opposita Thunb. The differences between Guangxi yam and Huai yam were researched in the aspects of pharmacognosy, TLC, Water content, total ash, water-soluble extract amount and the content of allenton, etc. the Harmful substance was determinated and storage methods were researched at the same time.Methods The quality research of Guangxi yam:1.The character identification method was visual observation.2. It was identified by the microscopic method and TLC.3. Water content, total ash and water-soluble extract amount were measured according to the China pharmacopeia (2010).4.Allenton content in Guangxi yam was measured by HPLC.The Chromatographic Column was ODS C18,the mobile phase was Methanol-water(1:9),the velocity was0.8mL/min,the column temperature was30°C.The detection wavelength was224nm.5. Pb, Hg, As, Cd, Cu, and SO2reissued in Guangxi yam were measured according to the appendix of the China pharmacopeia (2010). The research of storage:The influence of the different packaging material (plastic bags, aluminum foil bag) and different stabilizer (5%calcium chloride,5%the silica gel, the5%sodium sulfite deoxidization) to stability was evaluated With the factors of appearance characters, mildew to change, bug eat by moth, Water Content and water extracts.Results:Characters observations:This product was slightly cylindrical, bent and a little flat. The length was15to30cm, diameteris1.5-6cm. The colors on Surface are yellowish-white or light yellow. There were ditches, the marks of the fibrous root, and brown skin occasionally. It was Weight, solid, and hard to break. Section was white, powder. The smell was tenacity, it was tasted fresh and slightly acidic, chewing sticky. Microscopic identification:Guangxi yam’s powder was nearly white, starch grain was single and the shape was like flat ovoid, triangle or circle, the diameter was8-33μm. The sharp of umbilical point was punctuate word shape, patch the shape or short slit shape, visible layer lines; after grain of scarce, by2-3points of grain. Visible edge grain, include hole catheter, thread catheter and ring grain catheter, diameter12-48μm, about to180μm long, thick needle crystal2-4μm. Starch grain size, shape and size and type and catheter were the same as the Huai yam. TLC:Guangxi yam has the same dark blue dot with the dioscin as chemical reference substance, as the same as the reference drug. There were five Corresponding spots in reference drug, four corresponding spots in Guangxi yam, and seven Corresponding spots in Huai yam. Three inspection results:in Guangxi yam self-processing, Guangxi yam sulphur fumigated and Huai yam,Water Content were9.3%,11.8%and10.6%, the difference was significant between the Guangxi yam self-processing and Guangxi yam Sulphur Fumigated(P<0.05); Total ash were1.39%,1.44%,1.32%. The differences were not significant among the three groups (P>0.05).Water-soluble extract amount were14.6%,8.1%,17.8%. There were very significant differences at Guangxi yam self-processing compared with Guangxi yam sulphur fumigated and Huai yam compared with Guangxi yam sulphur fumigated(P<0.01),and significant differences at Guangxi yam self-processing compared with Huai yam(P<0.05). Content determination of Allantoin:in Guangxi yam self-processing, Guangxi yam without sulfur, Guangxi yam Sulphur Fumigated and Huai yam, content of allantoin were0.342%,0.309%,0.267%,0.628%. the difference was very significant between the Guangxi yam and Huai yam (P<0.01). the difference was significant between the Guangxi yam self-processing and Guangxi yam Sulphur Fumigated(P<0.05). Linear relationship is good in0.5-5.0μg. regression equations was Y=11967260X+85637.4, r=0.9996; Precision, stability and repeatability were qualified, average recovery was97.2%, RSD=1.36%. The contents of Pb,Hg, As, Cd, and Cu reissued were1.94,0.47,3.53,0.13,13.04ppm in Huai yam, were2.04,0.56,3.76,0.13,11.77ppm in Guangxi yam sulphur fumigated, were1.37,0.11,1.07,0.11,11.88ppm in Guangxi yam self-processing. The contents of SO2reissued in Huai yam Guangxi yam Sulphur Fumigated, Guangxi yam without sulfur, and Guangxi yam self-processing were580.2mg/kg,661.8mg/kg,59.3mg/kg,51.8mg/kg. Storage experiments:yam storage with aluminum foil bag vacuum packing was good. It is not mould and infesting, with water contents increased in the safe rage(less than16.0%), Extract was not changed.Conclusion:The result of The Guangxi yam was similar to Huai yam in microscopic, TLC, composition, water content, total ash Experiment. Water-soluble extract amount and the content of allenton in Guangxi yam was lower than in Huai yam.Heavy metals and SO2were increased after sulphur fumigated with aluminum foil bag storage vacuum packing was good. The experimental research shows that the Guangxi yam can used as Huai yam, but its quality had to be improved.