Antioxidant,anti-lipidemic,hypoglycemic and antiproliferative effects of phenolics from Cortex Mori Radicis

Cortex Mori Radicis (CMR) is enriched in various phenolics, this study aimed to estimate the antioxidant effect, enzyme (lipase, α-amylase, α-glucosidase and acetyl-cholinesterase) inhibition and the anti-proliferative effect of the phenolic compounds in CMR. However, the amount of these compounds obtained from CMR is highly dependent on the processing conditions. In this study, the processing parameters of extracting the phenolics from CMR using ultrasonic technique pooled with high-speed shearing extraction (UTPHSE) were optimized. Subsequently, the phenolics from Cortex Mori Radicis (PCMR) were purified using AB-8 macroporous resin, and their chemical analysis, antioxidant, enzyme inhibition, and antiproliferative activities were studied. Based on our findings, the optimal parameters of UTPHSE were: L/S ratio 25.8:1 (mL/g), voltage 81.0 V, ultrasonic temperature 51.8 ℃ and ultrasonic time 289 s. And under the optimal extraction conditions, the extraction rate of the PCMR was 0.531 ± 0.004%. Compared with PCMR, the contents of “total phenolics, flavonoids, flavonols, flavanols and phenolic acids” increased 2.30, 2.67, 2.59, 3.63 and 2.72 times in the purified phenolics from Cortex Mori Radicis (PPCMR), respectively. In addition, PPCMR depicted significant DPPH, ABTS⁺ and superoxide anion radicals’ scavenging capability, reducing power, ferric ion reducing antioxidant power (FRAP) and remarkable inhibitory activities on “lipase, alpha-amylase, alpha-glucosidase, and the proliferation of HeLa, HepG2 and NCI-H460”. At the same time, the morphological changes of HeLa, HepG2 and NCI-H460 cells suggested that PPCMR could effectively inhibit the proliferation of tumor cells in vitro. Therefore, PPCMR have good potential as natural antioxidants, antilipidemic, hypoglycemic, and antineoplastic agents in functional foods and pharmaceuticals.     

GC-MS联用技术结合化学计量学方法分析厚朴叶挥发油成分

利用水蒸气蒸馏法提取湖南产厚朴叶的挥发油成分,采用GC-MS联用技术结合化学计量学方法(直观推导式演进特征投影法和选择性离子法)进行分析,同时结合程序升温保留指数辅助定性。结果共鉴定出54种化合物,占挥发油总量的84.95%。主要化学成分为α-、β-和γ-桉油醇,含量分别为13.10%、28.21%和14.67%。此外,含量较高的化合物还有α-蒎烯(2.96%)、芳樟醇(1.71%)、丹皮酚(1.88%)、石竹烯(2.04%)、佛术烯(3.60%)、α-瑟林烯(3.84%)和[1AR-(1Aα,4α,4Aβ,7Bα)]-1A,2,3,4,4A,5,6,7B-八氢化-1,1,4,7-四甲基-1H-环丙烯并[E]奥(1.34%)。研究表明,将化学计量学方法用于中药挥发油成分的分析可提高定性分析的准确性。所得结果可为厚朴药植物资源的开发利用提供依据。     

Qualitative and Quantitative Analysis of Alkaloids in Cortex Phellodendri by HPLC-ESI-MS/MS and HPLC-DAD

A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was applied to the qualitative and quantitative analyses of alkaloids in Cortex Phellodendri(CP) samples, and to the differentiation of two species of CP, Cortex Phellodendri Chinensis(CPC) and Cortex Phellodendri Amurensis(CPA). Twenty-two peaks appeared in the HPLC-MS base peak chromatogram of CP detec...     

单扫描示波极谱法连续测定羊乳、黄芪、白鲜皮、蕨菜中铜和锌

研究了在HCl-KSCN底液中用单扫描示波极谱法连续测定羊乳、黄芪、白鲜皮、蕨菜中铜和锌含量的方法。在此底液中,铜和锌分别在-0．42和-1．03 V(vs．SCE)处产生一敏锐的二阶导数波,检出限分别为0．005和0．01 mg·L-1,线性范围分别为0．01～8．00和0．01-10．00 mg·L-1。应用此法测定羊乳、黄芪、白鲜皮、蕨菜中铜和锌含量,回收率在97．0％～101．7％。     

高效液相色谱法测定黄柏中盐酸小檗碱含量的不确定度评估

介绍一种高效液相色谱法测定含量的不确定度计算方法.通过黄柏中盐酸小檗碱含量测定结果,对产生不确定度的各分量进行计算,研究测量不确定度的主要分量,以控制检验环节的质量,保证结果准确度.     

Preparation of a stationary phase with quaternary ammonium embedded group for selective separation of alkaloids based on ion‐exclusion interaction

A stationary phase (named QA C10) with quaternary ammonium embedded between a propyl and a decyl chain was synthesized by immobilization of N,N‐dimethyldecylamine on chloropropyl–silica surface. A set of representative neutral, basic, and acidic compounds was employed to evaluate its chromatographic properties. The results illustrated that QA C10 was a mixed‐mode stationary phase possessing both hydrophobic and ionic characteristics. The QA C10 stationary phase was further used for selective separation of alkaloids from Cortex phellodendri. Under acidic condition, alkaloids could be eluted in first 8 min, while other neutral and acidic fractions were retained better on QA C10 column. Then, obtained alkaloid fraction was analyzed by LC‐MS/MS and 22 alkaloids were identified. Our study confirmed the advantages and application potential of the QA C10 stationary phase for alkaloids separation.     

不同产地杜仲的紫外光谱鉴别研究

利用不同溶剂在微波条件下对于3种不同产地杜仲进行提取,应用紫外分光光度计对相同溶剂的提取物进行研究,发现其紫外光谱有差异,可用于不同产地杜仲的鉴别.     

Assay of 44 compounds in the cortex and xylem from roots and branches of Ginkgo biloba L. by ultra high performance liquid chromatography coupled with tandem mass spectrometry and chemometric analysis

The leaves of Ginkgo biloba L. have received much attention, whereas there has been little systematic analysis of the cortex and xylem from roots and branches. A comprehensive evaluation of the 44 compounds in the cortex and xylem would thus be of value to fully understand the potential medicinal properties of roots and branches. An assay of amino acids, terpene lactones, flavones, and phenolic acids was accomplished using ultra high performance liquid chromatography with tandem mass spectrometry. All of the calibration curves showed good linear regression (R² > 0.9902) within the tested ranges. The intra‐ and interday precision was less than 4.9% and the accuracy was within ±6.8%. The amount of terpene lactones in the cortex was 1.75–2.07‐fold higher than that in the leaves. The amount of glutamine (360 μg/g) in the taproot xylem was 2.64‐fold higher than that in the leaves (136 μg/g). Principal component analysis decreased in the order leaves > taproot cortex > rootlet > laterals cortex > branch cortex > stem cortex > taproot xylem > branch xylem > laterals xylem > stem xylem. The taproot of G. biloba might provide a supplementary source of terpene lactones, especially ginkgolide A and C, and of glutamine.     

Development and validation of an LC-MS-MS method for determination of methyl kulonate in rat plasma

A sensitive, rapid and specific LC‐MS‐MS method was established and validated for determination of methyl kulonate, a major bioactive constituent isolated from Meliae Cortex, in rat plasma. Plasma samples were treated by precipitating protein with methanol and were chromatographed using a Capcell Pak C₁₈ column (100 × 4.6 mm, 5 µm) with the mobile phase comprising a mixture of methanol, 10 m m ammonium formate and formic acid (95:5:0.1, v/v/v). Detection and quantification were performed by mass spectrometry in the multiple reaction monitoring mode with positive atmospheric ionization at m/z 467 → 311 for methyl kulonate, and m/z 469 → 451 for dubione B (internal standard), respectively. A good linear response was observed over the concentration range 1.00–500 ng/mL with the lower limit of quantification 1.00 ng/mL in rat plasma. The method also afforded satisfactory results base on sensitivity, specificity, precision, accuracy, recovery, freeze–thaw and long‐time stability. The validated method was successfully applied to determine the pharmacokinetic properties of methyl kulonate in rats after oral administration at dose of 100 mg/kg. This pharmacokinetic study of methyl kulonate is reported here for the first time. Copyright © 2011 John Wiley & Sons, Ltd.     

定量测定秦皮中秦皮甲素的二阶导数示差脉冲极谱法

建立了中草药秦皮中秦皮甲素的二阶导数示差脉冲极谱定量分析方法。秦皮甲素在乙醇－2mol/L氯化锂－水（体积比2：1：5）的底液中,于－1．703V（vs Ag/AgCl)处出现一良好的二阶导数示差脉冲极谱峰,其峰幅值与秦皮甲素在0．2－1．6mmol/L范围内呈非常显著的线性关系（P＜0．01）,检测下限脒50mmol/L。该法简便、快速、灵敏,结果准确。