草菇培养物中粗三萜和黄酮含量及抗氧化抗肿瘤活性研究

采用液体摇瓶法培养草菇菌丝体,并用不同有机溶剂对培养液及菌丝体中的代谢成分分别进行分离提取,获得了不同来源的次生代谢提取物。对各提取物的成分分析表明,石油醚相、乙酸乙酯相和乙醇相提取物中均含有粗三萜和黄酮类物质,但菌丝体提取物中粗三萜和黄酮含量明显高于培养液提取物中的含量。石油醚抽提菌丝体获得的提取物中粗三萜含量最高,达17%,而乙酸乙酯抽提菌丝体获得的提取物中黄酮含量最高,达9.31%。抗氧化活性检测结果显示,石油醚相、乙酸乙酯相、乙醇相中的代谢提取物均有较高的抗氧化活性,但乙酸乙酯相提取物的抗氧化活性明显高于石油醚相提取物,具最高抗氧化活性的提取物分别来自乙酸乙酯、乙醇对菌丝体的抽提物。MTT法检测各提取物对胃癌细胞增殖的抑制作用,结果显示各组分均有较高的抗肿瘤活性,且抗肿瘤活性与提取物浓度存在明显的量效关系。     

药用真菌桑黄液体培养过程中的抗氧化活性研究

桑黄Sanghuangporus sanghuang是一种珍稀的药用真菌,具有较大的应用潜力。本研究主要以菌丝体生物量、多酚含量、黄酮含量、抗坏血酸(Ascorbic acid,AA)含量、总抗氧化能力(Total antioxidant capacity,T-AOC)、抑制羟自由基能力(Restraining ability to hydroxyl free radicals,RAHFR)、超氧阴离子清除能力、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除能力、2,2’-连氮-双(3-乙基苯并噻唑-6-磺酸)[2,2’-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid),ABTS]自由基清除能力、铁离子还原能力(Ferric reducing antioxidant power,FRAP)和亚铁离子螯合能力为测定指标,对桑黄液体培养过程中的抗氧化活性进行了评价。结果显示,菌丝体生物量在2–10d内增长迅速,第10天达到最大值,在此过程中AA含量和T-AOC也出现了峰值,且多酚含量、黄酮含量和FRAP均呈上升趋势,说明菌株的抗氧化活性与其自身的生长状况、次级代谢产物分泌及还原能力等密切相关。此外,该菌株对羟自由基、超氧阴离子、DPPH自由基和ABTS自由基的清除能力也较强,于第12天、第10天、第2天和第14天分别达到73.06U/m L、46.78%、86.47%和94.16%,显示了较强的抗氧化活性。较高的亚铁离子螯合能力也说明桑黄在氧化胁迫下可启动自身的抗氧化系统以阻断自由基链反应。研究结果为更好地研究、开发和利用药用真菌桑黄提供了基础资料。     

祁连山东段高寒草甸植物总酚和黄酮含量及抗氧化活性研究

采用Folin-Ciocalteu法和铝盐显色法对祁连山东段12种高寒植物(灌木嫩枝和草本植物叶片)进行总酚、黄酮含量的测定,并用FRAP法和ABTS法测定其总抗氧化能力。结果表明:(1)金露梅、山生柳、高山绣线菊、西藏沙棘、珠芽蓼的总酚和总黄酮含量较高且总抗氧化能力较强,其中山生柳的总酚含量最高为19.58%,高山绣线菊的黄酮含量最高为13.23%。(2)采用FRAP法测得西藏沙棘的抗氧化能力最强为49.58mmol/L,而用ABTS法测得金露梅的抗氧化能力最强为32.46mmol/L。(3)总酚、总黄酮与总抗氧化能力(FRAP法)具有极显著的相关性(相关系数分别为0.887 1和0.915 7)。分析认为,12种高寒植物的植株体内总酚和总黄酮含量越高,其抗氧化能力越强。     

灵芝子实体和孢子粉三萜含量的测定及体外抗肿瘤活性的评价

目的测定灵芝子实体和破壁灵芝孢子粉中的三萜含量,并评价其醇提物的体外抗肿瘤活性。方法采用高氯酸显色法测定灵芝子实体和破壁灵芝孢子粉中的三萜含量,采用磺酰罗丹明B蛋白染色法(sulforhodamine B,SRB)评价灵芝子实体和破壁灵芝孢子粉醇提物对宫颈癌He La细胞、结肠癌HCT-116细胞和乳腺癌MCF-7-ADM细胞的体外抗肿瘤活性。结果研究的灵芝子实体中三萜质量分数为0.92%,破壁灵芝孢子粉供试品中三萜质量分数实测值为2.95%,但是灵芝孢子粉中脂肪油对高氯酸显色法有极大的干扰,因此破壁灵芝孢子粉三萜的实测值可能远高于实际值。活性评价结果显示,灵芝子实体的醇提物在100μg/m L时,其对人宫颈癌He La细胞和乳腺癌MCF-7-ADM细胞表现出了较强的抑制作用,抑制率分别为94.54%和71.30%;对结肠癌HCT-116细胞表现出较弱的抑制作用,抑制率为20.68%。破壁灵芝孢子粉的醇提物在100μg/m L和10μg/m L时,其对宫颈癌He La细胞表现出了弱的抑制作用,对另外2种细胞系仅在100μg/m L时表现出较弱的抑制作用。结论灵芝子实体的醇提物含有三萜并具有较好的抗肿瘤活性,可以将其开发为辅助治疗癌症的药物或保健品。含有脂肪油的灵芝孢子粉直接采用高氯酸比色法测定会高估其三萜的含量,需要进一步开发准确、可行的测定方法。     

粗柄鸡菌菌丝体培养和无性繁殖过程研究初报

鸡菌属菌物是一类具有商业前景的食物蕈菌。对Ｔｅｒｍｉｔｏｍｙｃｅｓａｌｂｕｍｉｎｏｓｕｓ（Ｂｅｒｋ）Ｈｅｉｍ进行了广泛研究,其它种类的研究仅见于Ｔ．ｆｕｌｇｉｎｏｓｕｓ（Ｂｅｒｋ．）Ｈｅｉｍ。笔者首次对Ｔ．ｒｏｂｕｓｔｕｓ（Ｂｅｅｌｉ）Ｈｅｉｍ粗柄鸡菌进行了纯培养研究,其菌丝体生长所需的碳源以麦芽糖为佳,葡萄糖、蔗糖次之;氮源以蛋白胨、酵母粉较好;天然材料的热水提取物,如松针、蚁巢圃、马铃薯、平菇出菇废料、蚕豆的混合物能促进菌丝生长;培养基在ｐＨ４．５左右最佳,可用０．０５％的柠檬酸调节。菌丝体纯培养很容易形成大量分生孢子和小白球菌,表明小白球菌是粗柄鸡菌菌丝体无性繁殖过程的一个阶段。     

川芎粗多糖抗氧化和细胞毒活性研究

通过川芎粗多糖(LCP)对DPPH离子、超氧阴离子、.OH、总抗氧化能力、螯合能力、还原性和脂质过氧化能力的抗氧化效果和对肝癌细胞HepG2的抑制作用研究。结果显示:LCP具有较强的还原力,对超氧阴离子自由基、脂质过氧化产物有良好的抑制作用,其对肝癌细胞HepG2也具有一定的抑制作用。LCP有望作为天然抗氧化剂及功能性食品得到开发与应用。     

天山雪莲不同器官中黄酮、总酚含量和抗氧化活性分析

研究了天山雪莲不同部位的总黄酮、总酚含量及抗氧化活性。以天山雪莲根、茎、叶、花、花苞片为材料,测定其80%乙醇提取物的总黄酮含量、总酚含量、Fe3+还原力和对DPPH自由基的清除率。结果表明,天山雪莲中总黄酮和总酚的含量高低依次为叶花苞片≈花根茎;对Fe3+还原能力大小次序是叶花苞片花根茎;对DPPH的清除能力依次为叶≈花苞片花根茎。实验结果表明叶片可以作为天山雪莲采摘和药用的主要部位;天山雪莲花苞片中可能含有黄酮和酚类之外的抗氧化物质。     

4种地衣提取物抗氧化和抗肿瘤活性研究

本研究初步评估了4种药用地衣(太白茶、金刷把、黑石耳、红石耳)不同溶剂提取物的抗氧化活性及其粗多糖的抗肿瘤活性。通过测定清除DPPH自由基、羟基自由基和还原能力,对4种地衣不同溶剂提取物进行体外抗氧化活性评价,结果表明,金刷把和黑石耳的甲醇提取相清除DPPH自由基能力高于其它溶剂提取相,其IC50值(半抑制浓度)分别为0.7847 mg/mL和0.5595 mg/mL;黑石耳甲醇提取相(IC50=0.5747 mg/mL)清除羟基自由基能力优于阳性对照物Vc(IC50=0.6126 mg/mL);黑石耳氯仿提取相、金刷把乙酸乙酯提取相和太白茶甲醇提取相清除羟基自由基能力与Vc相当;4种地衣甲醇提取相还原能力均较强,且与其浓度呈较好的量效关系。利用MTT法分析4种地衣多糖对HeLa、A375和Hep G2细胞体外生长增殖的抑制作用,结果显示黑石耳粗多糖对Hep G2细胞的抑制作用较为突出(IC50=0.2567 mg/mL),而金刷把抑制HeLa细胞的生长增殖作用最强,其IC50值为0.4332 mg/mL。     

肿瘤坏死因子(TNF)的制备、纯化及其抗肿瘤活性的实验研究

 本文报道用卡介苗(BCG)和内毒素(LPS)诱导兎产生瘤肿坏死因子(TNF),获得含TNF血清(TNS)。TNS序顺通过DEAE-sephadex、SephadexG-200、Sephadex G-75和con-A-Agarose柱层析纯化,可获得单一电泳纯的TNF(SDS-PAGE和IEF),其分子量为67kD,等电点为pH5.2。抗肿瘤效应的结果表明,人胃癌细胞株:FGC-85和MGC-803对TNS/TNF敏感,SGC-7901不敏感;TNS/TNF可使小鼠移植性实体瘤(S_(180)、S_(37)、L_(Ⅱ)、U_(14)和黑色素瘤)发生出血性坏死,其中S_(180)对TNF最敏感。     

中药桑寄生凝集素的分离及体外抗肿瘤活性的研究

采用硫酸铵分级沉淀和酸化的Sepharose-4B亲和层析分离得到桑寄生凝集素;通过A-PAGE和SDS-PAGE电泳分析,确定所得凝集素组分和亚基情况;通过MTT法对所得到的凝集素进行体外抗肿瘤活性研究。研究结果表明,桑寄生凝集素包含两种组分,共含有四个亚基,亚基分子量分别为36.8 kDa、33.4 kDa,31.3 kDa和29.3 kDa;凝集素具有抗肿瘤效果,对肝癌BEL-7402细胞和胃癌MGC-823细胞的IC50分别为24.2μg/mL和20.9μg/mL。     

色钉菇子实体化学成分及其生物活性初探

从色钉菇Chroogomphus rutilus子实体中分离纯化出11种化合物,经核磁等方法鉴定为：（1）麦角甾-7,22-二烯-3-酮;（2）麦角甾-4,6,8(14), 22-四烯-3-酮;（3）邻苯二甲酸二丁酯;（4）顺式-3-己烯醇;（5）3β,5α,6β-三羟基麦角甾-7,22-二烯;（6）α-甜没药醇;（7）2-甲氧基腺嘌呤核苷;（8）(4E,8E)-2-N-(2-羟基棕榈酰)-1-O-B-D-吡喃葡萄糖基-9-甲基-4, 8-sphingadienine;（9）5-羟基尿嘧啶核苷;（10）2-氨基-3-醛基-6-甲氧基吡啶;（11）Polyozellin。对分离化合物的体外抗氧化、抗肿瘤活性的初步测定结果显示,2-甲氧基腺嘌呤核苷、顺式-3-己烯醇表现出较强的清除DPPH自由基活性,EC50值分别为0.06128mg/mL和0.08253mg/mL。5-羟基尿嘧啶核苷对人胃癌细胞株BGC的增殖有较强的抑制作用,IC50值为7.92μg/mL。研究结果为进一步开发利用色钉菇提供了科学依据。     

Five new quassinoids and cytotoxic constituents from the roots of Eurycoma longifolia

Eurycoma longifolia has been widely used for various traditional medicinal purposes in South-East Asia. In this study, five new quassinoids, eurylactone E (1), eurylactone F (2), eurylactone G (3), eurycomalide D (4), and eurycomalide E (5), along with ten known quassinoids (6–15) were isolated from the roots of E. longifolia. Their structures were determined by extensive spectroscopic methods, including 1D and 2D NMR, and MS spectra data. Among the isolated compounds, 13β-methyl,21-dihydroeurycomanone (6) has been reported as a synthetic derivative. However, it was isolated from the natural product for the first time in this study. The cytotoxic activities of fifteen compounds were evaluated against human lung cancer cell line, A549 and human cervical cancer cell line, HeLa.     

单叶蔓荆果实中多甲氧基黄酮类成分的分离、鉴定及细胞毒活性分析

Six polymethoxylated flavonoids were isolated from ethyl acetate fraction of ethanol extracts from Vitex rotundifolia Linn. f. fruit, and their structures were identified by NMR and MS methods, and cyt...     

Isolation, culture and immortalisation of hepatic oval cells from adult mice fed a choline-deficient, ethionine-supplemented diet

Oval cells have great potential for use in cell therapy to treat liver disease, however this cannot be achieved until the factors which govern their proliferation and differentiation are better understood. We describe a method to establish primary cultures of murine oval cells, and the derivation of two novel lines from these. Primary cultures from the livers of wildtype or TAT-GRE lacZ transgenic mice subjected to a choline-deficient, ethionine-supplemented diet comprised up to 80% oval cells at day 7 based on A6 or CK19 staining. Cell lines were clonally derived, which underwent spontaneous immortalisation following prolonged maintenance in culture. Immunostaining and RT-PCR demonstrated they express hepatocytic and biliary markers and they were therefore termed “bipotential murine oval liver” (BMOL) cells. Under proliferating culture conditions, BMOL or BMOL-TAT cells abundantly expressed oval cell and biliary markers, whereas mature hepatocytic markers were upregulated when the growth conditions were changed to facilitate differentiation. Hepatic differentiation of BMOL-TAT cells could be traced by measuring the expression of their lacZ transgene, which is driven by a promoter element from tyrosine aminotransferase (TAT), a marker of adult hepatocytes. Interestingly, haematopoietic markers were upregulated in superconfluent cultures, indicating a possible multipotentiality. None of the cell lines grew in semi-solid agar, nor did they form tumours in nude mice, suggesting they are non-tumourigenic.

These novel murine oval cell lines, together with a reliable method for isolation and culture of primary oval cells, will provide a useful tool for investigating the contribution of oval cells to liver regeneration.     

Extracellular and transmembrane region of a podocalyxin-like protein 1 fragment identified from colon cancer cell lines

Regulated intramembrane proteolysis of membrane proteins has been shown to play an important role in cell differentiation and in the pathogenesis of diseases. The aim of the present study was to identify novel peptides generated by intramembrane proteolysis. The peptides were identified in serum-free cultured (SFC) media from various cell lines by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). A 2315-Da peptide found only in medium from SFC colon cancer cell lines was identified and shown to consist of a portion of both the extracellular and transmembrane regions of human podocalyxin-like 1. This protein fragment was not found in lung or pancreatic cancer cell lines by immunoprecipitation-SELDI tests using an antibody specific to this fragment, suggesting that this human podocalyxin-like protein 1 fragment may be unique to colon cancer cell lines.     

Ursolic acid derivatives from Bangladeshi medicinal plant, Saurauja roxburghii: Isolation and cytotoxic activity against A431 and C6 glioma cell lines

Ursene-type pentacyclic triterpenes, including the ursolic acid, corosolic acid, and a new ursene-type pentacyclic triterpene, 7,24-dihydroxy ursolic acid, were isolated from the methanolic extract of the leaves of the Bangladeshi medicinal plant, Saurauja roxburghii, a higher plant indigenous to South East Asia and some part of North America. They were tested for the cytotoxicity against C6 rat glioma and A431 human epidermoid carcinoma cell lines. Although they have the same ursene-type pentacyclic triterpene core structure, the position and numbers of hydroxyl groups on the terpene structure significantly affected the activity and the selectivity to the cell lines.     

A bioassay for the simultaneous measurement of metabolic activity, membrane integrity, and lysosomal activity in cell cultures

The aim of this study was the development of an in vitro bioassay that combines several endpoints of general cytotoxicity for the screening of compounds or mixtures of compounds with potential bioactivity. The Alamar Blue assay was employed to assess metabolic activity, the Neutral Red assay was used for the assessment of membrane function and lysosomal activity, and the lactate dehydrogenase leakage assay was employed for the assessment of membrane integrity. Each assay was performed separately and in combination using a human fibroblast cell line (MRC-5). Three fungal secondary metabolites of different chemistry that affect different cellular targets were tested as model compounds: deoxynivalenol, enniatin B1, and 2-amino-14,16-dimethyloctadecan-3-ol. The obtained inhibitive compound concentrations for the assays performed separately and in combination were not significantly different (P < 0.05, n = 9). The combination of several cytotoxicity endpoints in a single assay increases the chance that potential bioactive/cytotoxic compounds are discovered during the screening of mixtures of natural compounds (e.g., extracts from fungal cultures or plants) when one endpoint fails and, at the same time, might give some basic information on the cellular target.     

The efflux of l-carnitine from cells in culture (CCL 27)

The efflux of l-[³H]carnitine was studied in cells from an established cell line from human heart (Girardi human heart cells, CCL 27). The cells were loaded with 4 μmol/l l-[³H]carnitine for 1 or 24 h, and the efflux of radioactivity into the medium was measured. The amount of intracellular l-[³H]carnitine retained was expressed as a function of time. The results were fitted to an exponential equation, from which efflux rate constants were computed.Increasing the extracellular concentration of butyrobetaine, l-carnitine, d-carnitine, betaine, dl-norcarnitine or 3-dimethylamino-2-hydroxypropionic acid each increased the observed efflux. This is most likely due to accelerated exchange diffusion. The substrate specificity of this accelerated exchange diffusion is different from what previously has been found in competitive uptake studies of l-carnitine. l-Carnitine was preferentially released to l-acetylcarnitine, and blocking the sulfhydryl groups with 5,5-dithiobis(2-nitrobenzoic acid) increased the efflux.     

Establishment and optimization of epithelial cell cultures from human ectocervix,transformation zone,and endocervix optimization of epithelial cell cultures

Cervical cancer is a major public health problem and research using cell culture models has improved understanding of this disease. The human cervix contains three anatomic regions; ectocervix with stratified squamous epithelium, endocervix with secretory epithelium, and transformation zone (TZ) with metaplastic cells. Most cervical cancers originate within the TZ. However, little is known about the biology of TZ cells or why they are highly susceptible to carcinogenesis. The goal of this study was to develop and optimize methods to compare growth and differentiation of cells cultured from ectocervix, TZ or endocervix. We examined the effects of different serum-free media on cell attachment, cell growth and differentiation, and cell population doublings in monolayer culture. We also optimized conditions for organotypic culture of cervical epithelial cells using collagen rafts with human cervical stromal cells. Finally, we present a step-by-step protocol for culturing cells from each region of human cervix.