八月瓜提取物对四氯化碳诱导小鼠肝损伤的保护作用

探讨八月瓜提取物不同极性部位对四氯化碳(CCl₄)所致小鼠肝损伤的保护作用。采用不同有机溶剂萃取,将八月瓜提取物分为石油醚相、乙酸乙酯相、正丁醇相和水相4个不同极性部位。给予0.3% CCl₄灌胃,建立小鼠肝损伤模型,检测各组小鼠血清中谷丙转氨酶(ALT)和谷草转氨酶(AST)活性,肝匀浆中超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量,并对肝组织进行病理学检查。八月瓜正丁醇提取物和水提取物能够明显降低模型小鼠血清ALT和AST活性,增强肝组织SOD活力,降低肝组织MDA含量,显著改善肝组织病变,减少肝细胞坏死。以上结果表明,八月瓜正丁醇提取物和水提取物对CCl₄致小鼠肝损伤有一定的保护作用。     

四氯化碳急性肝损伤敏感指标的研究

为研究四氯化碳急性肝损伤后各项生化指标及病理损伤的时间－反应关系,选用Ｗｉｓｔａｒ种雄性大鼠,随机分为５组,每组１０只。试验组动物给予２％ＣＣＬ４,灌胃１６０ｍｇ／ｋｇ ＢＷ,阴性对照组给予植物油。分别于染毒后１２、２４、４８、７２ｈ（对照组给油后２４ｈ）处死动物取静脉血测定血清ＧＰＴ、ＧＯＴ、ＴＧ含量,大鼠染毒后血清ＧＰＴ、ＧＯＴ含量显性升高,２４ｈ达到峰值后逐渐下降,７２ｈ接近正常;１２ｈ肝     

甘草、诃子提取物复合抗氧化剂对葵花籽油抗氧化作用的研究

目的研究甘草、诃子提取物复合抗氧化剂对葵花籽油抗氧化作用的影响。方法采用Schaal烘箱法和ABTS法,评价复合抗氧化剂对葵花籽油的抗氧化作用。结果 Schaal烘箱加速氧化实验中,甘草提取物比诃子提取物对葵花籽油的抗氧化作用更强,复合抗氧化剂均表现出协同抗氧化作用,其中,0.007%甘草提取物=0.013%α-生育酚、0.015%甘草提取物+0.005%抗坏血酸、0.007%诃子提取物+0.013%α-生育酚和0.003%诃子提取物+0.017%抗坏血酸对葵花籽油的抗氧化作用较强,均优于其单一抗氧化剂和人工合成抗氧化剂丁基羟基茴香醚(BHA)、2,6-二叔丁基-4-甲基苯酚(BHT),弱于2-叔丁基对苯二酚(TBHQ)。ABTS法中,多数复合抗氧化剂间表现出协同作用,其中,诃子提取物与抗坏血酸复配比例为5:1和3:1时清除ABTS自由基能力最强。结论复合抗氧化剂对葵花籽油具有协同抗氧化作用。     

西青果提取物对a-葡萄糖苷酶抑制活性的研究（III）

研究西青果提取物对小肠α - 葡萄糖苷酶的抑制作用。西青果提取物在体外和小肠模型人类结肠Caco-2 细胞中,显示很强的麦芽糖酶抑制活性,而对蔗糖酶的抑制作用不显著。在体内实验中,西青果提取物能降低SD雄性大鼠进食麦芽糖30min 后的血糖,而对进食蔗糖后的血糖浓度没有影响。实验结果表明西青果提取物可以预防Ⅱ型糖尿病。     

Hepatoprotective effects of almond oil against carbon tetrachloride induced liver injury in rats

This research aimed at evaluating the protective effects of almond oil against acute hepatic injury induced by carbon tetrachloride in rats. The study results showed that animals received almond oil prior to the administration of CCl₄ significantly decreased serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) activities, and total cholesterol (TC), triglyceride (TG) and low density lipoprotein (LDL) content, and increased serum high density lipoprotein (HDL) content. Whereas, pre-treatment with almond oil markedly increased rat hepatic superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) levels, and decreased the malondialdehyde (MDA) level. These results combined with liver histopathology demonstrated that almond oil has potent hepatoprotective effects, and could be developed as a functional food for the therapy and prevention of liver damage.     

Extracts of oyster mushroom (Pleurotus ostreatus) grown on wheat ameliorate hepatotoxicity induced by carbon tetrachloride in rats

Pleurotus ostreatus (PO), which is also called the oyster mushroom, is the secondly most popular cultivated mushroom in the world and has been shown to display antioxidant activity. In this study, the hepatic protective effects of extracts of PO cultured in wheat (POW) on carbon tetrachloride (CCl₄)-induced liver injury in rats were evaluated by analyzing blood markers of liver injury. Sprague-Dawley rats were pretreated with POW extracts (0, 0.5, and 1.0 g/kg) orally for 14 days prior to the administration of CCl₄ for 3 days. Marked evaluation of alanine and aspartate aminotransferases, lactate dehydrogenase, alkaline phosphatase, and γ-glutamyltransferase were observed in the plasma from control rats after CCl₄ treatment. This increased liver injury markers were significantly reduced in a dose-dependent manner by pretreatment with the POW extract, suggesting that POW prevented acute liver damage in CCl₄-intoxicated rats by suppressing cellular leakage and loss of the functional integrity of cell membranes in the liver. POW extracts could also improve lipid profiles damaged caused by CCl₄ in liver through a reducing plasma triglyceride and total cholesterol and a recovering plasma HDL-cholesterol. These results suggest that the extracts of POW ameliorate hepatotoxicity induced by CCl₄ in the rat model.     

营养型调和油配方及甘草、诃子提取物复合抗氧化剂对其抗氧化作用的研究

目的研究甘草提取物(Glycyrrhiza uralensis extract,GUE)、诃子提取物(Terminalia chebula extract,TCE)复合抗氧化剂对营养型调和油氧化程度的影响。方法采用气质联用(gas chromatography-mass spectrometer,GC-MS)方法测定原料油中各类脂肪酸的含量,根据数学模型制备营养型调和油;然后采用Schaal烘箱法,评价复合抗氧化剂对营养型调和油的抗氧化作用,筛选出抗氧化作用较强的复合抗氧化剂。结果调和油的最佳配比花生油68.68%、葵花籽油19.23%、亚麻籽油12.08%。复合抗氧化剂对调和油的抗氧化作用顺序为:0.003%GUE+0.017%Vc0.005%TCE+0.015%Vc0.017%TCE+0.003%Ve0.017%GUE+0.003%Ve,0.003%GUE+0.017%Vc对调和油的抗氧化作用最强,它优于丁基羟基茴香醚(Butyl hydroxyl anisole,BHA),与2,6-二叔丁基-4-甲基苯酚(2,6-Di-tert-butyl-P-cresol,BHT)相当。结论对于含有多不饱和脂肪酸多的贮存的油脂,甘草与诃子提取物复合抗氧化剂具有代替人工合成抗氧化剂的潜能。     

Hepatoprotective effects of sea buckthorn (Hippophae rhamnoides L.) against carbon tetrachloride induced liver injury in rats

BACKGROUND: Liver injuries induced by carbon tetrachloride are the best‐characterized system of xenobiotic‐induced hepatotoxicity and commonly used model for the screening of hepatoprotective activities of drugs. The present study evaluates the hepatoprotective activity of sea buckthorn (Hippophae rhamnoides L.), family Elaeagnaceae, on carbon tetrachloride (CCl₄)‐induced liver injury in male albino rats. The study was performed on Sprague–Dawley male albino rats weighing about 180–200 g. The animals were pretreated with three different doses of leaf extract (50, 100 and 200 mg kg^?1 body weight) for 5 days. Hepatotoxicity was induced by single oral administration of 1.5 mL CCl₄ kg^?1 body weight on the fifth day. The animals were then sacrificed and assessed for various biochemical parameters. RESULTS: Administration of CCl₄ significantly enhanced glutamate oxaloacetate transferase (GOT), glutamate pyruvate transferase (GPT), alkaline phosphatase (ALP) and bilirubin, and decreased total protein levels in the serum. Treatment with CCl₄ also significantly decreased reduced glutathione (GSH), and decreased glutathione peroxidase and superoxide dismutase activity. CCl₄ treatment also caused a significant increase in hepatic lipid peroxidation as assessed by malondialdehyde (MDA) levels in the tissue. Pretreatment of leaf extract at a concentration of 100 and 200 mg kg^?1 body weight significantly (P < 0.05) protected the animals from CCl₄‐induced liver injury. The extract significantly restricted the CCl₄‐induced increase of GOT, GPT, ALP and bilirubin and better maintained protein levels in the serum. Further, it also enhanced GSH and decreased MDA levels. CONCLUSION: The results show that sea buckthorn leaf extract has significant hepatoprotective effects which might be due to its antioxidant activity and can be developed as a nutraceutical or food supplement against liver diseases. Copyright © 2008 Society of Chemical Industry     

Antioxidant and antihepatotoxic effect of Spirulina laxissima against carbon tetrachloride induced hepatotoxicity in rats

The vast biodiversity of nature provides bioactive compounds that may be useful in the fight against chronic diseases. This study was designed to investigate the protective effects of the ethanol extract of Spirulina laxissima West (Pseudanabaenaceae) (EESL) against carbon tetrachloride (CCl(4)) induced hepatotoxicities in rats. Male albino rats of Sprague-Dawley strain were treated orally with the ethanol extract of S. laxissima (50, 100 mg kg(-1) body wt.) 1 h before each CCl(4) administration. The ethanol extract of S. laxissima showed the maximum antioxidant property in vitro. There were statistically significant losses in the activities of antioxidant enzymes and an increase in TBARS and liver function marker enzymes in the serum of the CCl(4)-treated group compared with the control group. However, all the tested groups were able to counteract these effects. The antioxidant activity of the extracts might be attributable to its proton-donating ability, as evidenced by DPPH. In the present study, the decline in the level of antioxidant observed in CCl(4)-treated rats is a clear manifestation of excessive formation of radicals and activation of the lipid peroxidation system resulting in tissue damage. The significant increases in the concentration of antioxidant enzymes in tissues of animals treated with CCl(4) + EESL indicate the antioxidant effect of EESL. This study suggests that EESL can protect the liver against CCl(4)-induced oxidative damage in rats, and the hepatoprotective effect might be correlated with its antioxidant and radical-scavenging effects.     

香辛料对二甲基亚硝胺形成的抑制作用

在体外条件下模拟二甲基亚硝胺(NDMA)的生成反应,对八角、丁香、洋葱、香菜、小茴香、大蒜这6种香辛料提取液的抑制NDMA生成的作用和加入剂量的关系进行研究.结果表明:在加入量逐渐加大的情况下,八角和丁香的抑制效果随之增强,最高可达到90%以上,大蒜和洋葱的抑制效果不明显,芫荽和小茴香的作用则是先强后弱,最终稳定在一定水平.     

冷压初榨椰子油对四氯化碳致小鼠 急性肝损伤的保护作用

研究了冷压初榨椰子油对四氯化碳（CCl4）诱导昆明小鼠急性肝损伤的保护作用。将72只昆明小鼠随机分成6组,包括正常组、四氯化碳肝损伤模型组、联苯双酯组（150 mg/kg）、椰子油低剂量组（5 mL/kg）、椰子油中剂量组（10 mL/kg）、椰子油高剂量组（20 mL/kg）,通过测定小鼠血清中丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）、乳酸脱氢酶（LDH）、甘油三酯（TG）和总胆固醇（TC）指标,肝组织中超氧化物歧化酶（SOD）活力、谷胱甘肽过氧化物酶（GSH-Px）活力及丙二醛（MDA）含量,采用HE染色切片对小鼠肝脏组织进行病理学检查,考察冷压初榨椰子油对四氯化碳致小鼠急性肝损伤的保护作用。结果表明：与模型组相比,不同剂量组的冷压初榨椰子油（5、10 mL/kg和20 mL/kg）可以不同程度地降低小鼠血清中ALT、AST、LDH、TG、TC水平以及肝组织中MDA含量,提高肝组织中SOD活力与GSH-Px活力;同时,肝脏组织病理学观察与生化指标检测结果一致。其中,高剂量的冷压初榨椰子油(20 mL/kg)作用效果优于阳性对照联苯双酯。研究表明冷压初榨椰子油对肝脏具有较好的保护作用,作用机制可能与其含有较多的抗氧化物质以及功能性物质有关。     

虫草素对脂多糖诱导巨噬细胞过度活化的抑制作用研究

目的:研究虫草素对脂多糖（LPS）诱导巨噬细胞过度活化的抑制作用。方法:培养RAW264.7小鼠巨噬细胞,采用LPS（1μg/m L）激活巨噬细胞,同时给予0.1¹0μmol/L的虫草素处理细胞,采用四甲基偶氮唑盐（MTT）法测定细胞存活率,Griess法检测细胞一氧化氮（NO）释放量,酶联免疫吸附分析实验（ELISA）分别检测三种细胞炎症因子肿瘤坏死因子α（TNF-α）、白介素-1β（IL-1β）和白介素-6（IL-6）的释放水平,采用Fluo-3/AM染色法以流式细胞仪测定胞浆游离钙离子浓度([Ca²⁺]i)的变化,采用水杨酸法考察虫草素对羟自由基（·OH）清除作用,L-酪氨酸法检测其对过氧亚硝酸根离子自由基（ONOO-）清除作用,邻苯三酚自氧化法检测其对超氧阴离子自由基（O₂^-·）清除作用。结果:虫草素在0.1¹0μmol/L浓度范围内可显著抑制LPS激活的RAW264.7巨噬细胞释放NO及3种炎症因子（IL-1β、IL-6和TNF-α）,同时对细胞存活率无显著影响;虫草素（10μmol/L）可显著抑制LPS诱导的巨噬细胞内[Ca²⁺]i水平异常升高;此外,虫草素对·OH、ONOO-和O₂^-·自由基具有显著清除作用。结论:虫草素可抑制LPS激活的RAW264.7巨噬细胞释放NO及炎症因子TNF-α、IL-1β和IL-6,这可能与其抑制了细胞内[Ca²⁺]i的增高及清除·OH、ONOO-和O₂^-·自由基有关。虫草素可能对巨噬细胞过度激活引起的炎症相关疾病具有一定的防治作用。      

Synergistic effect of copper ion on the reductive dechlorination of carbon tetrachloride by surface-bound Fe(II) associated with goethite

The dechlorination of carbon tetrachloride (CT) by Fe(II) associated with goethite in the presence of transition metal ions was investigated. X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRPD) were used to characterize the chemical states and crystal phases of transition metals on solid phases, respectively. CT was dechlorinated to chloroform (CF) by 3 mM Fe(II) in 10 mM goethite (25.6 m2 L(-1)) suspensions. The dechlorination followed pseudo-first-order kinetics, and a rate constant (k(obs)) of 0.036 h(-1) was observed. Transition metal ions have different effects on CT dechlorination. The addition of Ni(II), Co(II), and Zn(II) lowered the k(obs) for CT dechlorination, whereas the amendment of 0.5 mM Cu(II) into the Fe(II)-Fe(III) system significantly enhanced the efficiency and the rate of CT dechlorination. The k(obs) for CT dechlorination with 0.5 mM Cu(II) was 1.175 h(-1), which was 33 times greater than that without Cu(II). Also, the dechlorination of CT by surface-bound iron species is pH-dependent, and the rate constants increased from 0.008 h(-1) at pH 4.0 to 1.175 h(-1) at pH 7.0. When the solution contained Cu(II) and Fe(II) without goethite, a reddish-yellow precipitate was formed, and the concentration of Fe(ll) decreased with the increase in Cu(II) concentration. XPS and XRPD analyses suggested the possible presence of Cu2O and ferrihydrite in the precipitate. Small amounts of aqueous Cu(I) were also detected, reflecting the fact that Cu(II) was reduced to Cu(I) by Fe(II). A linear relationship between k(obs) for CT dechlorination and the concentration of Cu(II) was observed when the amended Cu(II) concentration was lower than 0.5 mM. Moreover, the k(obs) for CT dechlorination was dependent on the Fe(II) concentration in the 0.5 mM Cu(II)-amended goethite system and followed a Langmuir-Hinshelwood relationship. These results clearly indicate that Fe(II) serves as the bulk reductant to reduce both CT and Cu(II). The resulting Cull) can further act as a catalyst to enhance the dechlorination rate of chlorinated hydrocarbons in iron-reducing environments.     

诃子超微粉的工艺优化及其对黄嘌呤氧化酶活性的影响

目的制备诃子超微粉进行粉体学性质检测,对其制备工艺进行优化。方法:以黄嘌呤氧化酶(Xanthine oxidase,XOD)抑制率为评价指标,以球料比、冷冻时间、转速、球磨时间为影响因素进行单因素试验;在此基础上,正交实验试验优化诃子超微粉碎工艺。建立优化后的诃子超微粉的高效液相色谱(High Performance Liquid Chromatography,HPLC)指纹图谱,并与诃子超微粉进行对比。结果: 采用球磨法制备了诃子超微粉,诃子超微粉可显著改善普通粉的粉体学性质,降低药粉粒径;诃子超微粉最优制备条件为：球料比5:1、冷冻时间40 min、转速400 r/min、球磨时间1 h,优化后的超微粉粒径为22.4μm,5 mg/mL黄嘌呤氧化酶抑制率为69.10%。经HPLC分析,优化前后的二种诃子超微粉末指纹图谱主要成分基本一致,超微粉碎工艺未破坏诃子成分。结论:优化后的诃子超微粉抗黄嘌呤氧化酶活性更佳,为诃子超微粉在高尿酸血症中的应用提供了基础。     

紫娟茶提取物对酪氨酸酶活性的抑制作用

首先对从蘑菇中提取的酪氨酸酶的反应条件进行了探讨。采用单因素和正交实验确定了酪氨酸酶单酚酶和二酚酶活性的最适反应条件。结果显示单酚酶最适反应条件为:底物L-酪氨酸为10.0mmol/L,酪氨酸酶为0.30g/mL,反应时间为15min,反应温度为30℃;二酚酶最适反应条件为:底物邻苯二酚为7.5mmol/L,酪氨酸酶为0.035g/mL,反应时间为15min,反应温度为15℃。然后对紫娟茶的3种提取物的酪氨酸酶活性的抑制作用进行了探讨。结果表明,3种提取物对酪氨酸酶单酚酶和二酚酶活性均有较好的抑制作用,特别是含有花青素和茶多酚混合物的提取物I的抑制作用最强;3种提取物对单酚酶和二酚酶的半抑制浓度IC50分别为6.85×10-4、8.21×10-4、16.29×10-4g/mL和6.37×10-4、7.62×10-4、13.53×10-4g/mL。