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ObjectiveTo analyze the dynamic changes of the main chemical components and color characteristics of Polygoni Multiflori Radix（PMR） during the process of ancient classical nine-time repeating steaming and sun-drying， and to explore the correlation between the changes. MethodHigh performance liquid chromatography（HPLC） was used to determine the contents of gallic acid， stilbene glycoside， emodin-8-O-β-D-glucoside， physcion-8-O-β-D-glucoside， emodin and physcion in PMR during the process of nine-time repeating steaming and sun-drying， and electronic eye technology was used to objectively characterize the color of PMR during the process. Partial least squares（PLS） was used to analyze the correlation between the content of main components and the color characteristics. ResultDuring the nine-time repeating steaming and sun-drying process of PMR， the content of gallic acid gradually increased with the increase of steaming and sun-drying times， and the contents of other components showed fluctuating changes， with an overall decreasing trend in the contents of stilbene glycoside， emodin-8-O-β-D-glucoside and physcion-8-O-β-D-glucoside， and an overall increasing trend in the contents of emodin and physcion. The results of electronic eye analysis showed that the color of PMR became dark， red and blue in the process of nine-time repeating steaming and sun-drying. The results of hierarchical cluster analysis（HCA） and principal component analysis（PCA） of the contents of six main components and the colors showed that the samples steamed and sun-dried for one to four times could be grouped into one category， the other five categories of samples could be grouped into another category. Gallic acid and stilbene glycoside were significantly correlated with the color indexes of PMR during the process of nine-time repeating steaming and sun-drying. ConclusionThe general changes of material basis and color characteristics of PMR during the process of ancient classical nine-time repeating steaming and sun-drying have certain rules， and the establishment of the correlation model between color and index components can realize the judgment and quality evaluation of processing degree of PMR decoction pieces.
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Aims: Lovastatin is a cholesterol-lowering drug produced by several filamentous fungi as a secondary metabolite. Its concentration in mushroom can be affected by many post-harvest processes. In this study, fruiting bodies of Pleurotus ostreatus grown on corn cobs were used to evaluate the effect of conservation techniques on their lovastatin concentration. Methodology: acid and blanching treatments combined to different processes of fruiting bodies conservation like sun drying, oven drying and canning by autoclave cooking were tested to evaluate their effect on lovastatin concentration. Results: Sun drying, oven drying at 60°C/70°C and canning using autoclave cooking at 100°C did not significantly affect lovastatin concentration. On the contrary, oven drying at 80°C caused the reduction of this compound up to 45.4% with respect to fresh product irrespective of the precedent use of citric acid or blanching treatments. Also, during canning, the use of autoclave heat treatments at temperatures 110 and 121°C for 15 minute caused a significant reduction of lovastatin concentration of about 52.2% and 48.9% respectively compared to the control. In this regards, it can be concluded that processes that use dry thermal treatments higher than 80°C and autoclave heat treatments higher than 100°C will contribute to the reduction of lovastatin, the cholesterol-lowering compound in Pleurotus ostreatus.
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ObjectiveTo analyze the flavor substances and change rules of Rhei Radix et Rhizoma during the process of nine-time repeating steaming and sun-drying. MethodThe flavor response values of Rhei Radix et Rhizoma samples were obtained by using PEN3 electronic nose system. The data were processed and analyzed by principal component analysis （PCA）， linear discriminant analysis （LDA） and Loadings analysis. ResultRhei Radix et Rhizoma processed with nine-time repeating steaming and sun-drying could be effectively distinguished into two categories as the sixth sample was the turning point. The samples steamed and dried for one to five times could be grouped into one category， the other four samples were obviously distinguished from them. The main flavor components reached the maximum response in the sample processed with six-time repeating steaming and sun-drying， and its response value of inorganic sulfur compounds was about 2.7 times that of the sample processed with one-time repeating steaming and sun-drying. In addition， compared with the raw products， the flavors of Rhei Radix et Rhizoma processed with nine-time repeating steaming and sun-drying and wine stewing changed significantly， and the response value of inorganic sulfur compounds in sample processed with nine-time repeating steaming and sun-drying was about 2.2 times that of raw products. From the perspective of flavor analysis， the response values of inorganic sulfur compounds and nitrogen-oxygen compounds in sample processed with nine-time repeating steaming and sun-drying were higher than those of wine-stewed products， and the two were not completely equivalent. ConclusionElectronic nose technology preliminarily clarifies the dynamic change rules of the flavor of Rhei Radix et Rhizoma during the process of nine-time repeating steaming and sun-drying from the flavor characteristics， and clarifies the difference between products processed with nine-time repeating steaming and sun-drying and wine-stewed products from the odor characteristics， which lays a foundation for revealing the processing principle of Rhei Radix et Rhizoma processed with nine-time repeating steaming and sun-drying.
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The aim of this paper was to compare the influence of freeze-drying and sun-drying on six main nucleosides and nucleobases of Cordyceps sinensis by HPLC. Hypoxanthine,xanthine,uridine,inosine,guanosine and adenosine were reference substances. HPLC analysis was performed on a GL Inertsustain AQ-C_(18) column( 4. 6 mm×250 mm,5 μm),with mobile phase consisting of water( A)-acetonitrile( B) at the flow rate of 1. 0 mL·min~(-1)( 0-10 min,0-1% B; 10-65 min,1%-3% B). The detection wavelength was 260 nm,the column temperature was controlled at 30 ℃,and the injection volume was 5 μL. The linear ranges of hypoxanthine,xanthine,uridine,inosine,guanosine and adenosine were 1. 025-20. 50( r = 0. 999 8),0. 545-10. 90( r = 0. 999 9),4. 051-81. 02( r = 0. 999 8),4. 044-80. 88( r= 0. 999 9),2. 075-41. 50( r= 0. 999 9),4. 032-80. 64( r = 0. 999 9) mg·L~(-1),respectively. The average recoveries of them( n = 6)were as follows: 102. 3%( RSD 2. 1%),101. 1%( RSD 2. 4%),97. 80%( RSD 1. 7%),101. 8%( RSD 1. 8%),98. 90%( RSD2. 0%) and 98. 10%( RSD 1. 4%),respectively. Each sample was processed by freeze-drying and sun-drying so as to compare the difference between the two drying methods. The contents of six index ingredients were significantly different between freeze-drying and sun-drying sample of C. sinensis. The total contents of six index ingredients in sun-drying sample were higher than that in the corresponding freeze-drying sample. This research results provide the scientific basis for the drying methods and quality evaluation of C. sinensis.
Subject(s)
Chromatography, High Pressure Liquid , Cordyceps , Chemistry , Desiccation , Freeze Drying , NucleosidesABSTRACT
This study involved the molecular identification of Chlorella vulgaris microalgae obtained from Kaduna State University Fish Pond for biodiesel production potential. The DNA of Chlorella microalgae was extracted and subjected to PCR. The molecular weight of the PCR product obtained was 1.8kb using 18S rDNA primer sets and BLAST analyses revealed 95% identity with Chlorella vulgaris. The Chlorella vulgaris was cultured in open aquaria tanks at the Department of Biological Sciences, Nigerian Defence Academy. The biomass harvested was subjected to varying timings of sun and oven drying techniques (25-35ºC for 72hours and 60ºC for 12hours respectively) before extraction of oil from the biomass using solvent extraction method. The values for the density (0.854 and 0.867 cm3), specific gravity (0.875 and 0.876), acid value (0.414 and 0.384 mgKOH/g), saponification value (173.3 and 170.1 mgKOH/g), kinematic viscosity (5.200 and 3.870 mm2/g at 40ºC), flash point (114 and 115ºC) and cetane number (54.00 and 47.70) for the sun and oven dried biomass oil respectively were found to be in accordance with the ASTM standard values for biodiesel and fossil diesel. GC-MS analyses of the oil extracted using the two drying methods showed that the fatty acid profiling of the oil obtained from sun dried processed biomass had C14:0, C15:0, C16:0, C18:0, C18:1 cis9 and C22:1ω9 while the oven dried biomass oil had C14:0, C16:0, C19:0, C11:1, C18:1 cis9 and C22:1ω9. Drying methods, therefore, had influenced on the composition of saturated and unsaturated fatty acids. The oven dried biomass oil possesses high monounsaturated fatty acids when compared to sun dried biomass oil though the most important fatty acids (C14:0, C16:0 and C18:1) found in standard biodiesel were present in both. The results suggested that Chlorella vulgaris microalgae can be sustainably harvested for the production of biodiesel, both drying techniques can be employed for effective extraction but oven dried biomass oil was found to be of high quality because of the balanced in saturated and unsaturated fatty acid compositions and have an easy mode of operation but it required instrumentation.