仙草提取物对小鼠脾淋巴细胞DNA氧化损伤保护作用的研究

目的:观察仙草提取物对原代培养脾淋巴细胞H2O2所致DNA氧化损伤的保护作用。方法:原代培养24 h的脾淋巴细胞悬液,随机分为6组,其中4组细胞用不同浓度的仙草提取物溶液预先处理60 m in,再加入50μm o l/L的H2O2,H2O2染毒组直接加入相同浓度的H2O2,空白对照组加入等量的PBS溶液,6组细胞共同在4℃下染毒20 m in,收获细胞同时进行单细胞凝胶电泳,最后用激光共聚焦显微镜拍摄图像,计算DNA迁移的细胞率和总彗星长度。结果:H2O2可致原代培养脾淋巴细胞DNA的严重损伤,而仙草提取物能不同程度地降低H2O2诱导产生的DNA损伤,在10、50、100μg/m l的浓度下,彗星细胞出现率从阳性对照组的100%分别降低为88%、60%和36%(P分别<0.05、0.01、0.01),总彗星长度也从对照组的(49.56±6.94)μm,逐渐降低为(41.14±5.64)μm、(38.89±9.81)μm、(28.62±4.66)μm(P分别<0.05、0.01、0.01)。结论:仙草提取物具有显著的抗氧化功能,能在一定浓度范围内保护细胞免受氧自由基对DNA的氧化损伤。

Extraction and PTP1B inhibitory activity of bromophenols from the marine red alga Symphyocladia latiuscula

Previously, we had characterized several structurally interesting brominated phenols from the marine red alga Symphyocladia latiuscula collected from various sites. However, Phytochemical investigations on this species collected from the Weihai coastline of Shandong Province remains blank. Therefore, we characterized the chemical constituents of individuals of this species collected from the region. Eight bromophenols were isolated and identified. Using detailed spectroscopic techniques and comparisons with published data, these compounds were identified as 2,3-dibromo-4,5-dihydroxybenzyl methyl ether (1), 3,5-dibromo-4-hydroxybenzoic acid (2), 2,3,6-tribromo-4,5-dihydroxymethylbenzene (3), 2,3,6-tribromo-4,5-dihydroxybenzaldehyde (4), 2,3,6-tribromo-4,5-dihydroxybenzyl methyl ether (5), bis(2,3,6-tribromo-4,5-dihydroxyphenyl)methane (6), 1,2-bis(2,3,6-tribromo-4,5-dihydroxyphenyl)-ethane (7), and 1-(2,3,6-tribromo-4,5-dihydroxybenzyl)-pyrrolidin-2-one (8). Among these compounds, 1 and 2 were isolated for the first time from S. latiuscula. Each compound was evaluated on the ability to inhibit protein tyrosine phosphatase 1B (PTP1B), which is a potential therapeutic target in the treatment of type 2 diabetes. Bromophenols 5, 6, and 7 showed strong activities with IC50 values of 3.9, 4.3, and 3.5 μmol/L, respectively. This study provides further evidence that bromophenols are predominant among the chemical constituents of Symphyocladia, and that some of these compounds may be candidates for the development of anti-diabetes drugs.

Phytochemical Constituents and Allelopathic Effects of Some Medicinal Plants Extract on the Soil Algal Diversity

Phytochemical constituents of the shoots and roots extract of chosen eight medicinal plants （Plantago major, Verbesina encelioides, Glinus lotoides, Helotropium supinum, Mentha microphylla, Euphorbia hirta, Juncus subulatus and Convolvulus arvensis） were estimated using standard qualitative analysis. The extract contained alkaloids, glycosides, saponins, phenols, tannins, f[avonoids and terpenoids in some medicinal plants while others contain some only of these phytochemical components. Allelopathic effect of the various concentrations of the extracts on the soil algal diversity was also investigated. Wollea saccata was the only algal species disappeared from all applied investigated plant extracts. Phormidium richardsii, Monoraphidium braunii, Eunotia verneris and Nitzschia bilobata were the highly sensitive algal species to all applied shoot and root extract from all tested plants, they disappeared from most of the studied plants. On the other hand, Phormidium animale and Chlorella neustonice were highly tolerant algal species to all applied extracts. Counts of Cyanophyceae, Chlorophyceae and Bacillariophyceae were decreased by addition of some investigated medicinal plants extracts such as Juncus subulatus, Convolvulus arvensis and Euphorbia hirta. So the authors can use these plants extracts in biocontrol of the nuisance of algal bloom or any other microorganisms. Also, these plants may be useful to recover eutrophic water which needs further investigation.

Phytochemical Screening and Antimicrobial Evaluation of the Aqueous Extracts of Ammoides verticillata, an Endemic Species

Ammoides verticillata （Desf.） Briq. is an Algerian endemic species; the phytochemical screening （methods of Harborne, 1973） of the aerials parts wealth in polyphenol compounds： flavonoids, saponins, leucoanthocyanes, terpens and steroids and tannins; there is no alkaloids. There is an important quantity of essential oils in the flowers; the interest of this study is that this species remains until then it is not very known. The results of Aromatogram method by incorporation of Mtiller-Hinton on solid medium, showed a significant antimicrobial activity （method of Duraffourd, 1987） of the infusion and the ethanolic extract; the infusion of stems and flowers is indeed much more active on Echerichia coli, Citrobacter, Enterobacter, Staph aureus and Staph epidermidis, such as flowers extracts demonstrate an important antimicrobial activity on Staph aureus, Staph epidermidis, Streptococcus, Pseudomonas and Acinetobacter recognized as antibiotic resistant. This could give opportunities for using this species in the treatment of diverse infections and as a disinfecting additive on nosocomial area. The valorization, preservation and sustainable use ofAmmoides verticillata require the protection of its habitats.

Phytochemicals Analysis, Antioxidant Capacities and Antimicrobial Properties of Ethyl Acetate Extract of Stem Bark of the Garlic Tree Scorodocarpus borneensis Becc.

The objective of this study was to examine the phytochemical components, antioxidant activity and antibacterial property of ethyl acetate extract of the stem bark of garlic tree （Scorodocarpus borneensis）. The dried stem bark of S. borneensis were collected and homogenized after drying at room temperature （32℃） for 30 d. The stem barks were extracted by macerated method using 95% ethanol and then fractionated with ethyl acetate. The dried ethyl acetate extract was subjected to phytoehemical screening to determine the presence of bioactive components using gas chromatography-mass spectrometry （GC-MS）. Antioxidant activity of the extract in vitro was examined by 2,2-diphenyl-l-picryl-hydrazyl （DPPH） radical scavenging assay. The antibacterial activity against gram-positive bacteria Staphylococcus aureus and gram-negative bacteria Escherichia coli was performed by disc diffusion assay. GCMS results revealed the presence of 14 different phytocompounds, viz, tetratriacontyl trifluoroacetate （41.61%）, 2-pentanone （13.65%）, oxacyclotetradecane-2,11-done （7.87%）, cinnamic acid （7.53%）, 10-octadecanoic acid （6.50%）, 1,2-benzeno dicarboxylix acid （4.99%）, octadecanoic acid （4.51%）, hexadecanoic acid （4.16%）, beta tumerone （3.01%）, 9-octadecenoic acid （1.70%）, tricosanol （1.38%）, hexadecano-phenone （1.36%）, 1-nonadecanol （0.93%） and n-nonadecanol （0.82%）. In vitro antioxidant activity （IC50） was found at 55.524 ppm as high powerful. The results of agar diffusion method showed that the ethyl acetate extracts had an antibacterial activity of 6.687 ± 0.800 mm againts S. aureus at 10% （w/v） and 7.500 ± 0.735 mm against E. coli at 10% （w/v） as moderate category. These findings suggest that S. borneensis stem bark is a valuable sources of bioactive compounds with promising as antioxidant and antibacterial sources.

Investigation of Some Possible Mechanisms Involved in the Anticonvulsant Activity of Tulbaghia violacea Harv

Even though Tulbaghia violacea has been used to treat and manage epilepsy in South Africa by traditional medicine practitioners, no evidence in any literature has shown any scientific scrutiny of the effectiveness of the plant species in therapy. This study was intended, therefore, to investigate the anticonvulsant effect of the leaf methanol extract of Tulbaghia violacea by studying its effect against tonic convulsion induced by either PTZ （pentylenetetrazole）, bicuculline, picrotoxin, strychnine or NMDLA （N-methyl-DL-aspartic acid） in mice. Qualitative phytochemical analysis, acute toxicity and HPLC studies were also carried out on the plant species. Leaf methanol extract of Tulbaghia violacea, phenobarbitone, diazepam or muscimol significantly antagonised PTZ, bicuculline or picrotoxin-induced convulsion. Combined treatment of sub-effective doses of T. violacea and muscimol significantly antagonised tonic convulsion induced by PTZ. T. violacea or phenobarbitone significantly antagonised strychnine-induced tonic convulsion. T. violacea or LY233053 significantly antagonised NMDLA-elicited tonic convulsion. Phenytoin or DMSO （dimethylsulfoxide） did not significantly affect the tonic convulsion produced by PTZ, bicuculline, picrotoxin, strychnine or NMDLA. The phytochemical qualitative analysis of the plant species showed the presence of alkaloids, saponins, reducing sugars, flavonoids, cardiac glycosides, triterpene steroids, quinones and tannins. The LD50 value obtained following oral administration of the plant extract was over 4000 mg/kg. The data in the present study indicate that the leaf methanol extract of T. violacea has anticonvulsant activity which is probably underpinned by GABAergic, glutaminergic and glycinergic mechanisms.

In vitro Antimicrobial Activity and Phytochemical Screening of Local Plants

Antimicrobial activity of extracts of local plants was evaluated, with two strain i.e E. coil and S. aurri （gram positive and gram negative） microorganisms. The in vitro anti bacterial activity was performed by agar disc diffusion method. The most active antibacterial plants were S. trifiliatus and A. mexicana. The significant antibacterial activity of active extracts was compared with the standered, antimicrobics, streptomycin （10 μg/disc）. The results obtained in the present study suggest that S. trifoliatus and A. mexicana can be used in treating diseases caused by the test organism.

桑叶中芦丁和总黄酮含量测定相关性研究

目的研究芦丁和总黄酮含量作为指标的相关性,为桑叶产品制备过程中的质量控制提供参考。方法以铝盐络合比色法测定桑叶中总黄酮含量,并与HPLC测得的芦丁含量进行相关分析。结果桑叶中总黄酮含量与芦丁含量的等级相关分析P<0.05,表明2指标间存在直线相关性。结论铝盐络合比色法测定总黄酮含量与HPLC法测定芦丁含量均可单独应用于桑叶提取纯化的过程监测。