常德市野生马齿苋草粉饲用价值评价

对常德市盛花期野生马齿苋中水分、粗蛋白、粗脂肪、粗灰分、粗纤维、无氮浸出物、矿物元素、氨基酸进行了定量分析,以评定盛花期野生马齿苋草粉的饲用价值. 结果表明:盛花期野生新鲜马齿苋水分含量为90.15%,其草粉干物质中粗蛋白、粗脂肪、粗纤维、粗灰分、无氮浸出物的质量分数分别为22.94%、5.89%、25.18%、15.77%、30.22%;钙、磷、镁、锌、铁、铜、锰每百克的毫克量分别为970.96、570.36、3131.98、5.69、29.14、2.03、4.16;干物质中17种氨基酸总含量为12.96%,其中除色氨酸以外的7种必需氨基酸总含量为5.47%. 与盛花期苜蓿草粉及甘薯叶粉相应营养成分的比较结果表明盛花期野生马齿苋有较高的饲用价值,是一种较好的饲料资源.     

马齿苋挥发油的GC－MS分析

本文采用ＧＣ－ＭＳ法对本地马齿苋的挥发性成分进行了分离鉴定。初步分离出１９种成分，鉴定了１５种，其主要成分为芳樟醇（１８．９６％）和３，７，１１，１５－四甲基－２－十六烯醇（１３．５５％）。     

Pharmacokinetics and metabolism of olerciamide A from Portulaca oleracea L. in rats by UHPLC‐UV and UHPLC‐ESI‐Q‐TOF/MS

The aim of this study was to elucidate the pharmacokinetics of olerciamide A in rats after oral and intravenous administration of Portulaca oleracea L. extract by a simple and rapid ultra high‐performance liquid chromatography method with bergapten as internal standard. The pharmacokinetic results indicated that olerciamide A was rapidly distributed with a time to peak concentration of 30 min after oral administration and presented a low oral absolute bioavailability of 4.57%. The metabolism of olerciamide A in rats was also investigated using ultra‐high‐performance liquid chromatography electrospray coupled with quadrupole–time of flight mass spectrometry to elucidate the reason for the low absolute bioavailability of olerciamide A and seven metabolites of oleraciamide A were found in rat plasma and urine.     

马齿苋多糖的提取与其单糖组成研究

利用苯酚硫酸法对马齿苋多糖含量进行坝测定，设计正交实验确定马齿苋多糖提取的最佳工艺，马齿苋多糖的含量高达9．23％。将其多糖进行分离纯化，分得一种相对分子质量为411KD的多糖，进行理化性质试验测试，并利用纸层析和气相色谱对此马齿苋多糖中的单糖组成作了分析，其单糖组成为葡萄糖和半乳糖，其他单糖没有检出。     

胶束电动毛细管色谱安培检测中药马齿苋中多巴胺和去甲肾上腺素

建立了胶束电动毛细管色谱结合电化学安培检测同时分析中药马齿苋中多巴胺和去甲肾上腺素的方法。考察了缓冲液的浓度、pH值、十二烷基硫酸钠(SDS)浓度以及工作电极电势对分离检测的影响。在优化的条件下,多巴胺和去甲肾上腺素在1.0×10-6～5 0×10-4mol/L范围内有良好线性,浓度检测限(S/N=3)分别为8 7×10-7mol/L和4 2×10-7mol/L,质量检测限分别为1 45fmol和0 41fmol。该方法组分定性可靠,不需要衍生处理,选择性好。将该法应用于中药马齿苋样品的分析,获得了较好的结果。     

产黄酮马齿苋内生真菌的筛选及代谢产物抑菌效果初步研究

从马齿苋植株中分离内生真菌,提取其代谢产物,以黄酮类化合物显色反应和紫外光谱特征对内生真菌代谢产物进行初步鉴定,筛选得到产黄酮内生真菌AG-10,使用ITS1、ITS4通用引物,扩增菌株AG-10的18 S rDNA序列,结合菌落和分生孢子形态特征,对菌株AG-10进行分类鉴定,并采用滤纸片法研究AG-10的代谢产物抑...     

Pharmacokinetic studies of soyalkaloid A from Portulaca oleracea L. using ultra high‐performance liquid chromatography electrospray ionization quadrupole–time of flight mass spectrometry and its antioxidant activity

Soyalkaloid A was isolated from Portulaca oleracea L. for the first time in our laboratory and then a rapid and sensitive ultra‐high‐performance liquid chromatography electrospray ionization quadrupole–time of flight mass spectrometry (UHPLC–ESI–Q–TOF/MS) method with hesperidin as internal standard (IS) was developed and validated to investigate the pharmacokinetics of soyalkaloid A in rats after oral and intravenous administrations. The analysis was achieved on an Agilent Zorbax Eclipse Plus C₁₈ Column (2.1 × 50 mm, 1.8 μm) by elution with acetonitrile and water (containing 0.1% formic acid), at a flow rate of 0.3 mL/min. The MS analysis was performed in the positive ion mode with monitored ion m/z 227.0814 [M + H]⁺ and 611.1971 [M + H]⁺ for soyalkaloid A and IS, respectively. The linear range was established over the concentration range 7.5–6000 ng/mL (r = 0.9951). The intra‐ and inter‐assay accuracy and precision were between ?4.86‐4.49 and 1.93–9.66, respectively. The lower limits of detection and quantitation observed were 2.1 and 7.4 ng/mL, respectively. The rapid, sensitive and specific UHPLC–ESI–Q–TOF/MS method was successfully applied to a pharmacokinetic study of soyalkaloid A. Moreover, its antioxidant was studied via a 1,1‐diphenyl‐2‐picryl‐hydrazyl radical scavenging assay, the IC₅₀ value being 20.73 ± 0.51 μM.     

金荞麦多糖的超声提取及抗氧化作用研究

以多糖得率为指标,对影响多糖提取率的超声时间、温度、料液比进行单因素和正交试验;以清除自由基和抗猪油氧化作用探讨金荞麦多糖的抗氧化能力。结果表明,影响金荞麦多糖提取率的最主要因素是时间,最佳提取工艺条件为超声时间120 min、温度60℃、料液比1：20;金荞麦多糖可清除自由基,降低猪油过氧化值,具有体外抗氧化作用。     

马齿苋提取物对鲜切苹果褐变的影响

酶促褐变是影响鲜切果蔬品质及商业价值的关键问题之一。为探究马齿苋提取物在果蔬保鲜方面的应用价值,以鲜切苹果为研究材料,采用质量分数0.05%马齿苋提取物溶液浸泡鲜切苹果5min,在(4±1)℃存放8d。以鲜切苹果的褐变指数、多酚氧化酶(polyphenol oxidase,PPO)活力、苯丙氨酸解氨酶(phenylalanine ammonia-lyase,PAL)活力、过氧化氢酶(catalase,CAT)活力、过氧化物酶(peroxidase,POD)活力、丙二醛(malondiadehyde,MDA)含量、抗坏血酸含量以及DPPH自由基清除能力为评价指标,分析马齿苋提取物对鲜切苹果褐变及贮藏品质的影响。结果表明:与蒸馏水对照组相比,马齿苋提取物溶液处理能有效抑制鲜切苹果的褐变程度,在降低POD、PPO和PAL活力方面也有明显效果,能够在保证膜完整性的基础上减少细胞膜出现的损伤。相关性分析表明:鲜切苹果的褐变指数与CAT活力、抗坏血酸含量、DPPH自由基清除能力呈现极显著负相关(P<0.01),与MDA含量、PPO活力、POD活力、总酚含量呈极显著正相关(P<0.01)。马齿苋提取物溶液处理的鲜切苹果抗褐变效果较好,同时贮藏后鲜切苹果的抗氧化能力也有一定提高。     

Phytochemical characterization and radical scavenging activity of Portulaca oleraceae L. leaves and stems

The present work aimed to proceed to the phytochemical characterization of purslane (Portulaca oleracea L.) and study of its antioxidant activity. Different samples were analyzed for their moisture and fat content, fatty acids, organic acids and phenolic compound composition and the scavenging effect of DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals was evaluated. Water was the major constituent of purslane stems (average 90.5%) and leaves (average 91.8%), while fat values varied from 0.11% to 0.57%. Twenty seven fatty acids were found in the leaves samples, being linolenic acid the most abundant, ranging from 27.7 to 39.1%, followed by palmitic (19.3–24.3%) and oleic acids (11.6–19.5%). Five different organic acids were detected namely fumaric, aconitic, citric, malic and oxalic acids. Oxalic and citric acids were the most abundant, while aconitic acid was present in the lowest content. Two phenolic acids were identified and quantified: 3-caffeoylquinic and 5-caffeoylquinic acids. Leaves presented higher amounts of phenolic compounds, being 3-caffeoylquinic acid more abundant in leaves and 5-caffeoylquinic acid in stems. The leaves revealed to be the part with highest antioxidant potential.