Benzenetriol-Derived Compounds against Citrus Canker

In order to replace the huge amounts of copper salts used in citrus orchards, alternatives have been sought in the form of organic compounds of natural origin with activity against the causative agent of citrus canker, the phytopathogen Xanthomonas citri subsp. Citri. We synthesized a series of 4-alkoxy-1,2-benzene diols (alkyl-BDOs) using 1,2,4-benzenetriol (BTO) as a starting material through a three-step synthesis route and evaluated their suitability as antibacterial compounds. Our results show that alkyl ethers derived from 1,2,4-benzenetriol have bactericidal activity against X. citri, disrupting the bacterial cell membrane within 15 min. Alkyl-BDOs were also shown to remain active against the bacteria while in solution, and presented low toxicity to (human) MRC-5 cells. Therefore, we have demonstrated that 1,2,4-benzenetriol—a molecule that can be obtained from agricultural residues—is an adequate precursor for the synthesis of new compounds with activity against X. citri.     

高效液相色谱法检测食品中多种香料共存时的罂粟壳

 采用高效液相色谱法检测食品中多种香料共存时的罂粟壳。样品经碱化后采用氯仿 乙醇 (体积比为 9∶1)提取 ,在苯基柱上以乙腈 甲醇 水为流动相进行分离 ,外标法定量。罂粟碱 ,吗啡 ,可待因在 1 2mg/L～ 10 0mg/L范围内线性关系良好 ,平均回收率为 79.3%～ 86 .1%。该方法的专属性和准确度较高。     

基于近红外光谱技术与优化光谱预处理的陈皮产地鉴别研究

采集不同产地陈皮内侧和外侧的近红外光谱,采用不同光谱预处理方法进行预处理,筛选得到最佳光谱预处理方法,结合主成分分析法建立了陈皮产地的鉴别模型。实验发现,陈皮原始光谱中存在明显的基线漂移与背景干扰。使用单一光谱预处理可在一定程度上消除干扰的影响。经标准正态变量变换、多元散射校正、一阶导数、二阶导数与连续小波变换预处理后,陈皮内侧光谱数据可获得最优的鉴别结果,鉴别准确率为91.67%;通过最大最小归一化预处理后,陈皮外侧光谱数据可获得最优鉴别结果,鉴别准确率为70.83%;在2种预处理组合的鉴别结果中,有9个组合方式结合陈皮外侧光谱数据实现了对陈皮产地的100%鉴别分析,对于陈皮内侧光谱数据的最佳预处理组合为去趋势校正+最大最小归一化,鉴别准确率为95.83%;而3个预处理组合的鉴别准确率较2个预处理的结果低,表明采用预处理种类过多时可能会扣除有用信息。结果表明:近红外光谱技术结合光谱预处理可以实现不同产地陈皮的无损鉴别分析,其中陈皮外侧光谱数据结合优化光谱预处理方法可实现陈皮产地的100%鉴别分析。     

陈皮中农药残留分析及风险评估研究

通过分析中药陈皮的农药残留问题开展风险评估研究。采用气相色谱-串联质谱(GC-MS/MS)和高效液相色谱-串联质谱(HPLC-MS/MS)对198批陈皮中的117种农药进行检测;采用点评估方式计算陈皮中农药残留的急性和慢性摄入风险;采用英国兽药残留委员会提出的兽药残留风险排序矩阵计算各农药的风险得分;采用危害指数(HI)法计算有机磷农药的慢性累积风险。198批陈皮中共检出30种农药(含13种禁用农药),总检出率为98.5%,农药检出量为0.001~11.7 mg/kg。检出农药的慢性膳食摄入风险(%ADI)为0.003%~3.142%,急性膳食摄入风险(%ARfD)为0.022%~26.667%,风险均远低于100%,表明陈皮中农药的膳食暴露风险处于较低水平。6种有机磷农药的慢性累积暴露危害指数为0.942,略小于1,表明风险虽可控但需要关注。风险排序结果表明,陈皮中有16种为中高风险农药,应在生产和安全监管中重点关注。     

FTIR对不同产地陈皮的鉴别研究

采用傅里叶变换红外光谱法(FTIR)分析鉴别了7个不同产地的陈皮挥发油。结果表明,在红外图谱中,产自广东、广西的陈皮挥发油具有2-甲氨基-苯甲酸甲酯成分的一组相关峰;而两广区域外的陈皮挥发油在红外光谱图上观察不到该成分的特征吸收峰。其中,两广区域内新会陈皮与非新会陈皮在1 690与1 644 cm-1处的峰高比值有明显差异。该指纹特征可作为陈皮道地药材的一种简单、快速的鉴别依据。     

Kinetic features of Gualou-Xiebai-Banxia decoction,a classical traditional Chinese medicine formula,in rat plasma and intestine content based on its metabolic profile

Gualou-Xiebai-Banxia decoction (GXB) is a famous classical traditional Chinese medicine (TCM) formula for the treatment of coronary heart disease (CHD, namely chest stuffiness and pain syndrome in Chinese medicine). Compared with Gualou-Xiebai-Baijiu decoction, which only consists of Trichosanthis Pericarpium (TP), Allii Macrostemonis Bulbus (AMB) and wine, GXB comprises one additional herbal medicine, Pinellinae Rhizoma Praeparatum (PRP). However, due to a lack of kinetic profile studies on GXB, its in vivo components with high exposure remain unknown, making it difficult to interpret bioactive components likely linked to its efficacy, but also fails to provide substance-related evidence for reflecting the compatibility in GXB. The goal of this study was to systematically characterize the kinetic features of GXB in rat plasma and intestine content for revealing its in vivo high-exposure components on the basis of their metabolic fates, and to compare the kinetic differences between GXB and GXB-dePRP (GXB deducted PRP) for describing the chemical contribution of PRP to the compatibility in GXB. Firstly, the metabolic profile of GXB was systematically investigated by UPLC-Q/TOF-MS. Subsequently, quantitative methods for representative xenobiotics in rat plasma and intestine content were respectively validated and developed by UPLC-TQ-MS. Then, the established approaches were successfully applied to characterize the kinetic features of GXB through estimating pharmacokinetic parameters. These results showed that only a few kinds of xenobiotics at low exposure levels were observed in plasma, while various xenobiotics possessed high exposure in intestine content. Among them, steroidal saponins and triterpenoid saponins displayed relatively high exposure in plasma and intestine content, which are likely associated with the therapeutic effects of GXB. Moreover, there were no significant differences between metabolic profiles of GXB and GXB-dePRP, whereas the pharmacokinetic parameters, including area under the concentration–time curve (AUC) and C_max (p < 0.05) for most xenobiotics in GXB were significantly larger than those in GXB-dePRP, implying that the introduction of PRP improved the bioavailability of constituents from TP and AMB. Altogether, this study laid a solid foundation and provided theoretical guidance for further clarification of bioactive components of GXB, as well as the synergistic effect of PRP to the compatibility in GXB.