摘要：
The present study describes a rapid and sensitive HPLC method for the quantification of huperzine A (HupA) in Huperzia crispata (Huperziaceae). The sample extraction and preparation involved a simple, time-saving, single-solvent extraction, with each sample being analyzed within 12 min. The mobile phase was ammonium acetate (0.1 M, pH 6.0)-methanol (64 + 36, v/v) at a flow rate of 1.0 mL/min. Detection was at 308 nm. The calibration curve was linear from 0.049 to 7.84 μg (R<sup>2</sup> = 0.9997), with intraday and interday precision RSD of less than 2%. The extraction recovery rate was over 98.49%. Quantification of HupA was performed using this modified method, and the content of HupA was 1.86 times higher in the whole plant of H. crispata (218.17 ±1.55 μg/g) than in that of H. serrata (117.03 ±2.97 μg/g). In the whole plant of H. crispata, HupA mainly accumulated in the actively growing shoot tips, the apical bud, and the 10 youngest leaves, reaching 455.23 ±2.97 μg/g. The content of HupA in the samples from sunshine-sheltered sites was 3.45 times higher than in that from sunshine-abundant sites. The satisfactory results indicate that this modified method can be applied in the quality control of large-scale Huperziaceae plant extracts and that changes should be made in the cultivation of H. crispata so as to maximize the production of HupA.
作者机构：
[吴永尧; 雷红灵] College of Bioscience and Biotechnology, Hunan Agriculture University, Changsha 410128, China;[胡雪雷] School of Life Science and Technology, Jinan University, Guangzhou 510632, China;[雷红灵] Key Laboratory of Biological Resources Protection and Utilization of Hubei Province, Hubei University for Nationalities, Enshi 445000, Hubei, China
通讯机构：
College of Bioscience and Biotechnology, Hunan Agriculture University, China
作者机构：
[屠小菊; 唐冬英; 汪启明; 刘选明; 赵小英] State Key Laboratory for Chemical Biosensing and Chemometrics, Hunan Univ, Changsha, Hunan 410082, China;[汪启明] School of Biological Science and Technology, Hunan Agricultural Univ, Changsha, Hunan 410128, China
通讯机构：
State Key Laboratory for Chemical Biosensing and Chemometrics, Hunan Univ, China
作者机构：
[Xu, Xiaona; Liang, Yizeng] Cent S Univ, Coll Chem & Chem Engn, Res Ctr Modernizat Chinese Tradit & Herbal Drug M, Changsha 410083, Hunan, Peoples R China.;[Xu, Xiaona] Univ S China, Coll Chem & Chem Engn, Hengyang, Hunan, Peoples R China.;[Tang, Zhonghai] Hunan Agr Univ, Biosci & Biotechnol Coll, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Liang, Yizeng] C;Cent S Univ, Coll Chem & Chem Engn, Res Ctr Modernizat Chinese Tradit & Herbal Drug M, Changsha 410083, Hunan, Peoples R China.
作者机构：
[谢方平; 任述光; 汤楚宙] College of Engineering, Hunan Agricultural University, Changsha 410128, China;[卢向阳; 孙松林] College of Bioscience and Technology, Hunan Agricultural University, Changsha 410128, China;[罗锡文] College of Engineering, South China Agricultural University, Guangzhou 510642, China
通讯机构：
College of Engineering, South China Agricultural University, China
作者机构：
[武深树] College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128, China;[黄璜] College of Agronomy, Hunan Agricultural University, Changsha 410128, China;[龙岳林; 甘德欣] College of Horticulture and Landscape, Hunan Agricultural University, Changsha 410128, China;[谭美英] Hunan Quality Quarantine and Examination Center for Livestock, Poultry and Aquaculture Products, Changsha 410006, China;[武深树; 朱好] Hunan Animal Husbandry and Aquaculture Bureau, Changsha 410006, China
通讯机构：
College of Agronomy, Hunan Agricultural University, China
摘要：
Comparison of the volatile constituents of different parts of Cortex magnolia officinalis by GC-MS combined with chemometric resolution method Volatile compositions of different parts (stem, branch and root barks) of Cortex magnolia officinalis, cultivated in China, were investigated for the first time by GC-MS with the help of heuristic evolving latent projection (HELP). Identification of components was conducted by similarity matching to NIST mass library but also assisted by comparison of temperature-programmed retention indices (PTRIs) with the data web available. A total of 90, 82 and 76 volatile compounds in the essential oils of the three samples taken from the same batch aforementioned were qualitatively and quantitatively determined, representing 84.03, 83.68 and 83.10% of the total content, respectively. Among the constituents determined, there were 50 components coexisting. Eudesmol and its isomers were shown to be the principal compounds in the studied samples, accounting for 47.66, 36.74 and 36.31%, respectively. The three kinds of isomers (a-, band c-eudesmol) in houpo volatile oils have been tentatively qualified and quantified simultaneously for the first time. By comparative analysis, significant qualitative and semi-quantitative differences and similarities were observed among the three samples. The results achieved provide a scientific evidence for further exploitation of Magnolia bark and clinical medication.
作者机构：
[He, Feifei; Chen, Qing; Zhang, Fusuo; Su, Fang; Jiang, Rongfeng] Key Laboratory of Plant-soil Interactions of Ministry of Education, Key Laboratory of Plant Nutrition of Minstry of Agriculture, College of Resources and Environmental Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing 100193, China;[He, Feifei] College of Bioscience and Biotechnology, Hunan Agricultural University, Furong District, Changsha 410128, China
通讯机构：
[Su, F.] K;Key Laboratory of Plant-soil Interactions of Ministry of Education, Key Laboratory of Plant Nutrition of Minstry of Agriculture, College of Resources and Environmental Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, China
摘要：
Laboratory batch experiments were conducted to study arsenic （As） removal from a naturally contaminated soil using phosphoric acid （H_3PO_4） and potassium dihydrogen phosphate （KHEPO_4）. Both H_3PO_4 and KHEPO_4 proved to reduce toxicity of the soil in terms of soil As content, attaining more than 20% As removal at a concentration of 200 mmol/L. At the same time, acidification of soil and dissolution of soil components （Ca, Mg, and Si） resulted from using these two extractants, especially H_3PO_4. The effectiveness of these two extractants could be attributed to the replacement of As by phosphate ions （PO~(3-)_4）. The function of H_3PO_4 as an acid to dissolve soil components had little effects on As removal. KH_2PO_4 almost removed as much As as H_3PO_4, but it did not result in serious damage to soils, indicating that it was a more promising extractant. The results of a kinetic study showed that As removal reached equilibrium after incubation for 360 rain, but dissolution of soil components, especially Mg and Ca, was very rapid. Therefore dissolution of soil components would be inevitable if As was further removed. Elovich model best described the kinetic data of As removal among the four models used in the kinetic study.
作者机构：
[Hao, Xiao-Jiang] Kunming Inst Bot, State Key Lab Phytochem Plant Resource W China, Kunming 650204, Yunnan, Peoples R China.;Hunan Agr Univ, Coll Living Creature Sci & Technol, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Coll Hort & Landscape, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Hao, Xiao-Jiang] K;Kunming Inst Bot, State Key Lab Phytochem Plant Resource W China, Kunming 650204, Yunnan, Peoples R China.
关键词：
Cipadessa cinerascens;Tetranortriterpenoids;Triterpenoids;Cipadesin D and E
摘要：
Two new tetranortriterpenoids, cipadesin D (1) and E (2), were isolated from the stems of Cipadessa cinerascens. Their structures were elucidated by analysis of their spectroscopic data.
摘要：
The water-soluble antioxidant, chlorogenic acid, was successfully encapsulated in the low cost-high volume yeast cells for the first time, as characterized by FT-IR spectra and fluorescence micrograph of the yeast cells, chlorogenic acid and microcapsule. The encapsulation efficiency (EE) of yeast cells could be enhanced significantly (P < 0.001) by the treatment of yeast cells with plasmolyser before encapsulation. Also, the release characteristics of the obtained yeast-encapsulated chlorogenic acid were evaluated, and its storage stability as a powder were investigated at 25 degrees C/75% relative humidity (RH), 25 degrees C/90% RH and 60 degrees C. It could be clearly demonstrated that no chemical changes had taken place during the encapsulation, and the yeast-encapsulated chlorogenic acid exhibited a good stability. This study would be helpful to promote the application of chlorogenic acid. The new yeast-cell-based encapsulation protocol may have some general interests for maintaining the stability of other water-soluble substances. (c) 2006 Elsevier Ltd. All rights reserved.
摘要：
The piezoelectric bulk acoustic wave (BAW) impedance analysis method was employed to monitor in situ the proteinase-catalyzed hydrolyzation of casein and the effect of pesticide D-allethrin on the proteinase activity in the midgut of the spider Pardosa pseudoannulata, and the results obtained were verified by ultraviolet spectroscopy. The hydrolyzation was significantly increased in the presence of low-dose D-allethrin, whereas significantly inhibited in the presence of high-dose D-allethrin, and a correlation was found precisely between the enzyme activity reflected by the final frequency shift after the hydrolyzation and the concentration of D-allethrin, with a significant frequency response observed even at a 1.5 × 10-5 volume ratio of D-allethrin to distilled water. The present work may have presented a novel method feasible for study on the mechanism of excitability of spiders under low-dose D-allethrin pesticide and quick detection of proteinase activity.
