红雪茶混合物对小鼠辐射损伤的保护作用

目的 对云南生物资源进行抗辐射保健食品的开发性研究。方法 对云南多种生物资源配方成分进行抗辐射损伤的筛选实验,对其中有作用的红雪茶混合物再进行剂量-效果的观察实验。通过照射前后给予受试物,检测各剂量组受照小鼠的白细胞数、骨髓嗜多染红细胞微核数,观察照射后30 d的平均存活天数。结果 筛选实验表明:红雪茶混合物及螺旋藻混合物具有一定的抗辐射作用。进一步的红雪茶剂量-效应观察试验表明:红雪茶混合物的低、中、高三个剂量均组可降低5 Gy γ射线诱发小鼠骨髓嗜多染红细胞微核发生率;对小鼠白细胞具不同程度的提升作用,对8 Gy受照小鼠30 d存活率在高剂量组有明显保护作用。结论 红雪茶混合物对接受γ射线全身照射小鼠的辐射损伤有一定的保护作用。     

苹果提取物抗辐射效应的研究

目的 :　研究苹果提取物的组成成分及其抗辐射效应。方法 :　利用分光光度法及HPLC法分析苹果提取物中酚类物质 ,并采用灌胃方式给予实验小鼠 ,连续灌胃 30 d后接受 7Gy60 Co-γ射线一次性辐照 ,照射后一半动物取血进行白细胞计数 ,另一半动物观察平均存活时间和 30d存活率。结果 :　 (1 )苹果提取物中主要的酚类成分为原花青素低聚体 ,儿茶素单体 ,酚酸 ,黄酮等酚类物质。 (2 )灌胃高剂量苹果提取物 30 d的小鼠经 7Gy一次性辐射后 ,第 7d小鼠白细胞数量比辐射对照组提高了 1 1 2 % (P<0 .0 1 ) ,第 1 4 d小鼠白细胞数量提高了 52 % (P<0 .0 5) ;且苹果提取物高剂量组小鼠的 30 d存活率明显高于辐射对照组 (P<0 .0 5)。 (3)服用中、高剂量的小鼠比辐射对照组平均存活天数分别提高了 72 % (P<0 .0 1 )和 69% (P<0 .0 1 )。结论 :　苹果提取物对 7Gy剂量一次性照射具有拮抗作用。其主要成分可能为原花青素低聚体 ,儿茶素等酚类物质。     

β-胡萝卜素的抗辐射作用

目的 研究β-胡萝卜素的抗辐射作用。方法 采用30、60、90mg／kg β-胡萝卜素的剂量对昆明种小鼠进行30d灌胃,然后用4和8 Gy的^60Co-射线照射小鼠,照射后仍给以原剂量灌胃,并进行动物平均生存时间、存活率、白细胞计数、骨髓细胞微核、睾丸染色体畸变、免疫功能、组织中超氧化物歧化酶(SOD)活力等的检测。结果 各剂量组β-胡萝卜素均能在一定程度上阻止由辐射引起的白细胞下降,提高被辐射小鼠的免疫功能,升高组织中SOD活力,并有抑制微核产生的作用,同时在一定程度上减少由^60Co-1射线而引起的小鼠睾丸染色体畸变,而且可延长动物的生存时间,提高动物的30d存活率。结论 β-胡萝卜素具有抗辐射作用。     

生姜提取物对X射线损伤小鼠白细胞的保护作用

目的：研究生姜提取物对X射线损伤小鼠白细胞的保护作用。方法：分别选择3种剂量（9．3ml／kgwt、4．7ml／kgwt、2．3ml/kgwt）的生姜提取物，给小鼠灌胃后，以剂量为2Gy的X射线照射，间隔24h后，以相同剂量的生姜提取物再灌胃、照射。末次照射结束后48h，将小鼠断头处死，抗凝取血，测定外周血液中WBC、LYM、MID、GRAN的变化。结果：X射线可使外周血中WBC数量明显下降，淋巴细胞比例明显降低，中间细胞及粒细胞的比例明显上升。各剂量生姜提取物对雌性小鼠WIN；数下降无明显影响，高剂量生姜提取物组LYM比例明显高于单纯照射组（P〈0．05）；中剂量生姜提取物组雄性小鼠血中WBC数与未照射组无明显差异，高剂量生姜提取物组的LYM比例与未照射组无明显差异（P〉0．05）。结论：适当剂量的生姜提取物对一定剂量X射线引起的小鼠外周血白细胞损伤具有保护作用。     

葡萄籽提取物对辐射所致小鼠氧化损伤的影响

为探讨葡萄籽提取物对小鼠的抗辐射保护作用,将50只昆明雄性小鼠随机分为辐射模型组、溶剂对照组、低(0.083 g/kg)、中（0.167 g/kg）、高（0.500 g/kg）剂量葡萄籽提取物组,用葡萄籽提取物灌胃25,25 d后除溶剂对照组外以7Gy60CoΥ射线对小鼠进行一次性全身照射,继续给予葡萄籽提取物灌胃7d...     

莲房原花青素对~(60)Co-γ射线致亚急性辐射损伤防护的研究

目的:研究莲房原花青素(LSPC)的抗辐射作用。方法:80只小鼠分4组,实验组分别连续灌胃不同剂量(50、100、200mg/kgbw)的LSPC15d后,接受60Co-γ射线8.0Gy照射后,一半动物观察平均存活时间和30d存活率。另一半动物于照射后不同时间检测外周血白细胞、红细胞、血小板、血红蛋白含量。结果:小鼠经8.0Gy60Co-γ一次全身辐照后,100、200mg/kgbwLSPC组能使小鼠平均存活时间分别提高49.2%和58.3%,存活率明显高于对照组,且各组小鼠的保护指数均大于1.0;外周血像于照后21d基本恢复正常,且以200mg/kgbwLSPC组效果最佳。结论:LSPC对8.0Gy60Co-γ射线亚急性辐射损伤有一定的保护作用。     

银杏叶黄酮抗辐射效应研究

目的:研究银杏叶中黄酮的抗辐射作用。方法:以碱性水提取法从银杏叶中分离出总黄酮(GBF),调配成低剂量(10 mg/100 ml)、中剂量(20 mg/100 ml)、高剂量(100 mg/100 ml)水溶液,分别给小鼠灌胃,10 d后,以总剂量8.5 Gy 60Co-γ射线整体辐射,再灌胃10 d,观察30 d存活率。另取小鼠,分六组(低、中、高GBF剂量组,辐射对照组,正常对照组,及环磷酰胺组),分别灌胃低、中、高剂量GBF水溶液,另三组灌胃蒸馏水,连续11 d后,低、中、高剂量GBF组及辐射对照组以总剂量1.0 Gy γ射线照射,再灌胃7 d,灌胃停止后D21 测小鼠骨髓微核率及精子畸变率及淋巴细胞测转化率。结果:低、中、高剂量GBF水溶液可分别提高辐射小鼠存活率31.7 %,25.3 %和26.5 %( P<0.05),低剂量GBF使淋巴细胞转化率显著提高(P<0.01),骨髓微核率及精子畸变率有一定程度降低。结论:低剂量银杏叶黄酮具有较强的抗辐射作用,其作用机制与提高小鼠免疫力有关。     

茶多酚对~(60)Coγ射线诱发小鼠外周血淋巴细胞Hprt基因突变的影响

目的探讨茶多酚(tea polyphenols,TP)对~(60)Coγ射线诱发小鼠外周血淋巴细胞Hprt基因突变的影响。方法小鼠分为正常对照组、照射组(1、2、4、8 Gy照射),TP保护组(高、中、低剂量组分别于8 Gy照射后TP灌胃725 mg/kg、145 mg/kg、29 mg/kg),每组6只,照射后当日给药,14天后心脏取血,应用多核细胞法检测Hprt基因位点突变频率。结果 0~8 Gy~(60)Coγ射线可诱发小鼠淋巴细胞Hprt基因发生突变,且随照射剂量增加突变频率随之增加,突变频率Y(10-3)与照射剂量D(Gy)间可拟合为Y=1.1795+0.6135D。TP保护组Hprt基因突变率与照射组细胞Hprt基因突变率相比明显下降(P0.01)。结论茶多酚对~(60)Coγ射线所诱发的小鼠外周血淋巴细胞Hprt基因突变具有保护效应。     

富勒醇对小鼠γ射线辐射损伤的防护作用

目的研究C60衍生物富勒醇对小鼠~(60)Coγ射线辐射损伤的防护效果。方法ICR小鼠于照射前5d至照后7d连续腹腔注射富勒醇,~(60)Coγ射线全身均匀照射,照射剂量分别为5Gy和8Gy,照射剂量率1.0Gy/min,测定5Gyγ射线照射下小鼠体重变化,照后7d胸腺、脾脏指数外周血白细胞;8Gyγ射线照射下30d存活率和平均生存时间。结果富勒醇能减轻~(60)Coγ射线辐射所引起的外周血白细胞、血小板降低,胸腺和脾脏萎缩;提高小鼠生存率,延长存活时间。结论富勒醇对~(60)Coγ射线照射的小鼠具有一定的防护作用。     

低剂量12C6+离子辐射诱导的小鼠骨髓细胞适应性反应实验研究

目的研究低剂量重离子辐射(LDR)对小鼠造血系统的适应性反应特征。方法对小鼠给予大剂量(2.0 Gy)12C+6射线照射前预先采用0.050,0.075 Gy 12C+6离子束全身照射,其中一批小鼠24 h处死,测定外周血指标、脏器系数、骨髓细胞微核率、骨髓DNA含量;第二批小鼠接受大剂量(2.0 Gy)全身辐照后观察其30 d存活情况。结果与大剂量直接照射组相比,0.050Gy低剂量照射组小鼠外周血白细胞明显升高,骨髓DNA含量升高,小鼠骨髓细胞的微核率降低(均P<0.05~0.01),其余指标无统计学差异。0.075 Gy低剂量照射后小鼠外周血白细胞与照射对照组比较有一定下降,其余指标无明显差异。结论低剂量碳离子束照射能拮抗大剂量照射后引起的骨髓细胞损伤,对造血组织产生适应性反应,对重离子治疗肿瘤及放射防护具有一定参考意义。     

石榴皮抗氧化物质提取及其体外抗氧化作用研究

目的: 研究石榴皮提取物体外清除自由基的作用及对低密度脂蛋白(LDL)氧化的影响。方法: 采用 -2O、·OH、ROO·等自由基的生成体系,研究石榴皮提取物清除自由基的活性,并进一步采用LDL体外氧化模型,研究对LDL氧化的抑制作用,并与石榴果汁提取物相比较。结果: 两种提取物均可以有效清除 -2O、稯H、ROO纷杂苫种芁DL氧化,其活性具有剂量效应关系;果皮提取物的各种活性均强于果汁提取物。结论: 石榴皮所含天然抗氧化物质能有效清除 -2O、稯H、ROO返茸杂苫种芁DL氧化,因而可能具有抑制动脉粥样硬化(AS)的作用。     

石榴籽提取物体外抗氧化活性研究

目的研究石榴籽提取物的体外抗氧化作用。方法采用普鲁士蓝法、邻二氮菲-Fe2+氧化法和邻苯三酚自氧化法分别测定石榴籽提取物的总抗氧化能力、石榴籽提取物对羟自由基(.OH)和超氧阴离子(.O2-)的清除作用,并与维生素C抗氧化活性相比较。结果石榴籽提取物对.OH和.O2-具有很强的清除作用,其IC50分别为0.157和0.027mg/ml,与维生素C抗氧化作用相似。结论石榴籽提取物具有较强的清除自由基能力,是一种天然有效的抗氧化剂。     

Study on the antioxidant activity of tea flowers (Camellia sinensis)

Major chemical compounds in different extracts from tea flowers (Camellia sinensis) were analyzed. Distilled water or 70% ethanol extracts were then fractionated with chloroform, ethyl acetate and n-butanol, respectively. Each extract fraction was tested its scavenging activities on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl free radicals. The results showed that ethyl acetate fraction of ethanol-extract of tea flower (EEA) exhibited the highest quenching activity to hydroxyl radicals (SC50 11.6 mug/ml), followed by ethanol-extract (EE) of tea flower (SC50 19.7 microg/ml). Same tea flower extract showed big different scavenging activities on different free radicals. EEA quenched 80% of hydroxyl radicals generated by Fenton's reaction, however, only 40% of DPPH radical was scavenged in the Fe (II)-H2O2 -luminol system. The contents of flavones, polyphenols and catechins in EE and EEA fractions were higher than those in other fractions. We suggest that the stronger scavenging abilities to free radicals might be due to polyphenols, EGCG, ECG and flavones. However, the water extracts of tea flower and their fractions showed lower antioxidant activity for their inhibitory effect on hydroxyl radicals and DPPH radicals.     

Evaluation of in vitro antioxidant activity of Sida rhombifolia (L.) ssp. retusa (L.)

Sida rhombifolia (L.) ssp. retusa (L.) is widely used in Ayurvedic medicine for the treatment of fever as well as a diuretic. The comparative antioxidant potentials of ethanol extract of roots, stems, leaves, and whole plant were studied. Estimation of total polyphenolic content and high-performance thin-layer chromatography profile were determined. Further inhibition of oxygen-derived free radicals, viz., assays for free radical scavenging, reducing power, superoxide anion scavenging, nitric oxide scavenging, and anti-lipid peroxidation, were performed. All the antioxidant activities were compared with standard antioxidants such as butylated hydroxyanisole and alpha-tocopherol acetate. Extracts were found to be good scavengers of the 1,1-diphenyl-2-picrylhydrazyl radical in the order root > leaves > whole plant > stem with 50% inhibitory concentrations of 546.1, 852.8, 983.8, and 1,222.5 microg/mL, respectively. All extracts of this plant showed effective free radical scavenging activity, reducing power, and superoxide scavenging activity. Only root extract inhibited lipid peroxidation in rat liver and brain homogenate. All these antioxidant properties were concentration dependent. In addition, total polyphenolic contents of all the extracts were determined as gallic acid equivalents. The highest antioxidant activity was observed in root extract. The results obtained from the current study indicate that S. rhombifolia ssp. retusa is a potential source of natural antioxidants.     

Antioxidant properties of extracts from a white mutant of the mushroom Hypsizigus marmoreus

A white mutant of Hypsizigus marmoreus (Peck) Bigelow (Tricholomataceae) is a new edible mushroom currently available in Taiwan. The ethanolic and hot water extracts were prepared from fruit bodies and mycelia and their antioxidant properties studied. In addition to EC₅₀ values in scavenging abilities on hydroxyl radicals, almost EC₅₀ values were less than 10 mg/mL indicating that these extracts were effective in antioxidant properties assayed. The major antioxidant components found in hot water extracts were total phenols (10.01–13.14 mg/g) and those in ethanolic extracts were total tocopherols (33.33–10.92 mg/g). Correlations of contents of total antioxidant components and total tocopherols (plus β-carotene) with EC₅₀ values of antioxidant activity, reducing power, scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals and chelating ability on ferrous ions were established (r=0.445–0.940), whereas the correlation of total phenol content was established only with that of scavenging ability on hydroxyl radicals (r=0.882).     

The food additives inulin and stevioside counteract oxidative stress

Prebiotics such as inulin (Inu)-type fructans and alternative natural sweeteners such as stevioside (Ste) become more popular as food ingredients. Evidence is accumulating that carbohydrates and carbohydrate-containing biomolecules can be considered true antioxidants, capable of scavenging reactive oxygen species (ROS). Here, we report on the ROS scavenging abilities of Inu and Ste in comparison with other sugars, sugar derivatives and arbutin. It is found that Inu and Ste are superior scavengers of both hydroxyl and superoxide radicals, more effective than mannitol and sucrose. Other compounds, such as 1-kestotriose, trehalose, raffinose and L-malic acid, also showed good reactivity to at least one of the two oxygen free radicals. The strong antioxidant properties of Inu and Ste are discussed. Within the plant vacuole, these compounds could play a crucial role in antioxidant defense mechanisms to help survive stresses. Addition to food assists in natural sweetening, food stabilization and maximizes health impact.     

紫甘薯花青素的稳定性及抗氧化性研究

目的探明紫甘薯花青素的稳定性和抗氧化性,为紫甘薯花青素在食品中的加工利用提供理论依据。方法采用HPLC和LC-MSn对ZA1紫甘薯花青素成分进行了分析。比较花青素在室内自然光,紫外光,沸水浴高压灭菌和不同pH值条件下的稳定性。研究了其清除超氧阴离子自由基、羟基自由基和DPPH.自由基等抗氧化性能力。结果紫甘薯花青素成分包括有矢车菊素、飞燕草素、锦葵色素、牵牛花色素和甲基花青素。自然光和紫外光照对花青素稳定性影响较小,高温对花青素稳定性影响较大。pH值对花青素稳定性影响非常大,低pH有利于花青素保留。pH为7.0时,花青素具备较好的清除超氧阴离子、羟基自由基和DPPH.自由基能力。结论紫甘薯花青素稳定性受光照、温度、pH值影响。紫甘薯花青素具有较强的抗氧化能力。     

Antioxidant activity of methanolic extract of emblica fruit (Phyllanthus emblica L.) from six regions in China

The phenolic contents of methanolic extracts of emblica (Phyllanthus emblica L.) fruit from six regions in China were measured in this work. The antioxidant activities of these extracts were also evaluated. Total phenolic content was ranged from 81.5 to 120.9 mg gallic acid equivalents (GAE)/g and the flavonoid content was varied from 20.3 to 38.7 mg quecetin equivalents (QE)/g, while proanthocyanidin content was ranged from 3.7 to 18.7 mg catechin equivalents (CE)/g. Among all the methanolic extracts analyzed, the Huizhou sample exhibited a significantly higher phenolic content than other samples (P<0.05). The antioxidant activities were evaluated by in vitro experiments using scavenging assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, and superoxide anion radicals, chelating ability of ferrous ion, reducing power, and inhibition capability of Fe (II)-induced lipid peroxidation, respectively. The Huizhou sample was found to have the strongest antioxidant activities in scavenging DPPH radicals, superoxide anion radicals, and had the highest reducing power, while the Chuxiong sample showed the best performance in chelating iron and inhibiting lipid peroxidation. Furthermore, the Chuxiong sample exhibited a stronger inhibition activity of the hydroxyl radicals compared with other samples. The high correlation coefficient was existed between the phenolic content and superoxide anion radical scavenging activity, but no significant correlation was found between the former and hydroxyl radical scavenging activity. Methanolic extracts of emblica fruit from some selected regions exhibited stronger antioxidant activities compared to those of the commercial compounds (quercetin and BHA). It might be considered as a potential plant source of antioxidants.     

Radical scavenging, antibacterial, and antiproliferative activities of Melissa officinalis L. extracts

The aromatic herb Melissa officinalis L. can be used as an easily accessible source of natural antioxidants and as a possible food supplement and as a phytochemical. Radical scavenging, antibacterial, and antiproliferative activities of petroleum ether, chloroform, ethyl acetate, n-butanol, and water extracts of M. officinalis L. extracts were investigated. The results of antioxidative activity, obtained by electron spin resonance spectroscopy, confirmed that investigated extracts suppressed the formation of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and lipid peroxyl radicals in all investigated systems in a dose-dependent manner. The maximum DPPH and hydroxyl radical scavenging activities (SA(DPPH) = SA(OH) = 100%) were achieved in the presence of n-butanol extract at concentrations of 0.4 mg/mL and 0.5 mg/mL, respectively. The highest lipid peroxyl scavenging activity (93.20%) was observed at a higher concentration (5 mg/mL) of n-butanol extract in the lipid peroxidation system. The most effective antibacterial activities were expressed by petroleum ether and ethyl acetate extracts on Sarcina lutea. Chloroform extract showed the strongest antiproliferative effect with 50% inhibitory concentration values of 0.09 mg/mL and 0.10 mg/mL for HeLa and MCF-7 cell lines, respectively. The present study demonstrated the high phenolic content and radical scavenging, antibacterial, and antiproliferative activities of extracts of M. officinalis L. originating from Serbia.     

富硒螺旋藻清除氧自由基的初步研究

目的与方法:采用化学发光法研究富硒螺旋藻提取液、硒藻蓝蛋白、硒藻多糖、亚硒酸钠对超氧阴离子(_O2?)和羟自由基(·OH)的清除作用。结果:当体系中提取液浓度达400μg/ml时,富硒比未富硒螺旋藻提取液对_O2?的清除率提高30%,对·OH的清除率提高20%;硒藻蓝蛋白_比藻蓝蛋白对_O2?和·OH的清除作用有所提高,并呈现明显的剂量相关性,O2?50%清除率蛋白浓度为500μg/ml,·OH50%清除率蛋白浓度为125μg/ml;硒藻多糖对氧自由基具有极强的清除效率,_O2?和·OH50%清除率时的浓度分别为12μg/ml和60μg/ml;另外,在实验浓度范围,未检测到亚硒酸钠对超_O2?和·OH具有清除作用。结论:富硒螺旋藻可能因硒的代谢而产生活性有机硒态如硒藻蓝蛋白、硒多糖等,从而提高其清除自由基活性。