番木瓜叶片多酚的提取及抗氧化性能研究

以甲醇溶液作为提取试剂,以山奈酚和维生素C为对照,通过DPPH和ABTS自由基清除能力、总还原能力以及铁离子还原/抗氧化能力测定(FRAP)番木瓜叶片提取物的抗氧化能力。结果表明,该种方法提取总酚产率较高,并且番木瓜叶片提取液具有良好抗氧化活性和自由基清除能力,番木瓜叶片提取液的自由基清除能力与溶液中总酚的浓度呈正比关系。     

2009年河北省核桃冻害调查与分析

对河北省不同地区核桃冻害的调查分析结果表明:核桃品种不同抗冻能力不同,辽宁1号、辽宁7号、香玲有较强的抗冻能力,而中林1号、清香等抗冻能力较差;在一定范围内,树龄越小抗冻能力越差;合理的管理措施可有效提高核桃树体的抗冻能力;核桃高接后会降低越冬抗冻能力,必须加强后期管理。     

《试验设计与统计》实验课教学改革的探讨

针对试验设计与统计课程实践性和应用性强的特点,从优化实验教学内容入手,改革实验教学方法,培养学生实践能力和创新能力为主;引入统计软件,改革实验教学方法,培养学生的动手能力;改革考核方式,注重学生实践能力考核。实践证明,对《试验设计与统计》实验课进行教学改革,提高了实验课的教学效果,培养了学生的综合实践能力,提高了学生试验设计能力和统计分析能力。     

黑果枸杞抗氧化能力评价及比较研究

本文以青海黑果枸杞为研究对象,选择宁夏黑果枸杞、宁夏红枸杞、黑醋栗干、蓝莓干、桑葚干和黑加仑葡萄干等其他6种干果作为对照,通过清除羟自由基能力、抑制超氧阴离子能力和总抗氧化能力(T-AOC)等指标的测定,对7种干果的抗氧化能力进行了比较分析和系统评价。结果表明,7种干果中青海黑果枸杞抗羟自由基和总抗氧化能力最强,宁夏黑枸杞则抑制超氧阴离子能力最强,而宁夏红枸杞和桑葚干在全部检测数据中,显示抗氧化能力较弱。从总体上看,黑枸杞表现出了更好的抗氧化能力。     

山楂若干开花结果习性的观察研究

从2014年起对山楂的不同长度和粗度结果母枝的成花能力,自花、单性、自然授粉的结实能力,以及顶、腋花芽的比例和成花能力等开花结果习性进行观察试验研究,从而掌握山楂的若干开花结果习性。结果表明:山楂结果母枝的质量对其成花能力影响很大,长、壮结果母枝成花能力非常明显地强于短弱母枝;山楂具有一定的自花结实和单性结实能力,人工辅助授粉可明显提高坐果率;山楂形成腋花芽的能力很强,腋花芽是主要的结果部位。     

树莓自生繁育能力评价

为了探究树莓自生繁育能力,以15份不同品种的树莓为试验材料,调查其基生枝出土期、落叶期、根蘖数量。结果表明,‘秋福’‘欧洲红’萌蘖能力最强,‘大图’‘哈瑞太兹’萌蘖能力较强,‘威拉米特’和‘努卡’的萌蘖能力最弱,其余品种萌蘖能力一般。     

120份石榴种质果实的抗日灼能力评价及抗日灼指标筛选

【目的】明确不同石榴种质果实日灼发生情况及其抗日灼能力,进而筛选出反映果实抗日灼能力的生理指标。【方法】调查了120份石榴资源的日灼发生率和日灼指数,并对其进行抗日灼能力评价。对15份具不同抗日灼能力的资源进行总抗氧化能力评价,并测定果皮日灼面的几种抗氧化物质含量,最后对日灼指数、总抗氧化能力及相关生理指标进行相关性分析。【结果】不同石榴种质果实的日灼发生率和日灼指数具明显多样性。15份不同资源的总抗氧化能力和抗氧化活性物质含量表现出明显的基因型差异。线性回归和相关性分析表明,日灼指数与总抗氧化能力呈现极显著正相关;相关性分析表明,日灼指数与抗坏血酸、总酚、花青素、谷胱甘肽、总黄酮含量呈极显著正相关(p 0.01),日灼指数与类胡萝卜素含量之间没有明显的相关性。进一步分析发现,总酚、抗坏血酸和谷胱甘肽与总抗氧化能力的相关性最强(p 0.01)。【结论】不同石榴种质果皮的抗日灼能力具有明显的多态性;总抗氧化能力可以反映其抗日灼能力,总酚、抗坏血酸和谷胱甘肽含量可以很大程度上反映其抗氧化能力。     

冬生多孔菌发酵液代谢产物及抗氧化能力

测定冬生多孔菌(Polyporus brumalis)液体培养过程中的菌丝体生物量,发酵液中乙醇沉淀物、多酚、黄酮及抗坏血酸含量,发酵液的超氧化物歧化酶活性、总抗氧化能力、铁离子还原能力、亚铁离子螯合能力以及对DPPH自由基、ABTS自由基、羟自由基、超氧阴离子的清除能力;分析代谢产物与抗氧化指标之间的相关性。结果表明,在14 d的培养过程中,菌丝体生物量以及发酵液中的乙醇沉淀物、多酚、黄酮含量分别在第8、14、10、8天达到最大值(7.14±1.30)g·L~(-1)、(4.03±0.06)μg·mL~(-1)、(59.10±3.80)μg·mL~(-1)、(0.94±0.05)mg·mL~(-1);发酵液不具有铁离子还原能力和亚铁离子螯合能力,但超氧化物歧化酶活性、总抗氧化能力以及对DPPH自由基、ABTS自由基、羟自由基、超氧阴离子的清除能力均较强;多酚含量与总抗氧化能力、羟自由基清除能力之间,黄酮含量与DPPH自由基清除能力之间,抗坏血酸含量与ABTS自由基、超氧阴离子清除能力之间具有较强的相关性。本研究表明冬生多孔菌发酵液具有良好的抗氧化能力,为其开发利用提供参考。     

李属果树果实营养成分及抗氧化活性检测研究进展

李多样性丰富,分布广泛,营养价值和保健价值越来越被人们重视。与其他果实相比,李果实中的维生素C含量、膳食纤维含量、多酚类物质含量和抗氧化活性能力都相对较高。目前对果实抗氧化活性的测定方法主要有清除DPPH自由基能力测定法、清除ABTS自由基能力测定方法、还原Fe3+能力(FRAP)测定方法和清除氧自由基能力(ORAC)测定方法。由于没有统一的标准方法,所以在研究某种物质的抗氧化能力时,一般采取两种或两种以上的方法来共同说明其抗氧化能力。笔者对抗氧化活性的含量及测定方法的国内外研究进展进行了综述。     

毛木耳多糖水提液抗氧化能力研究

院以两种毛木耳子实体粉体为原料,采用常规方法测定毛木耳多糖水提液的DPPH自由基清除能力、超氧阴离子清除能力、羟基自由基清除能力。通过对比研究发现,随着粉碎细度的增加,毛木耳多糖水提液抗氧化能力明显提升。     

Antioxidant Capacity,Phenolic Compounds and Antioxidant Enzymes of Wild Grape Seeds from Different Accessions Grown in Iran

Grape seeds contain high levels of phytochemicals, that have been associated with a reduced risk of chronic diseases. In this study, the polyphenolic content, antioxidant capacity and antioxidant enzymes activity in the seeds of 20 wild grape accessions native to Iran were investigated. The antioxidant capacity of the wild grape seeds was evaluated by DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe²⁺ chelating. Total phenolic (TP), total flavanoid (TF) and total proanthocyanidin (TPA) content ranged from 44.86 to 155.1, 23.21 to 131.91, and 10.11 to 26.10?mg/g seed, respectively. All seed extracts showed remarkable DPPH radical scavenging activity, ferric reducing antioxidant power (FRAP) and Fe²⁺ chelating ranging from 27.34 to 78.57%, 198.83 to 590.86?µmol TE/g and 23.12 to 62.98%, respectively. Grape seed extracts had the greatest antioxidant enzymes activity guaiacol peroxidase (G-POD), superoxide dismutase (SOD), and catalase (CAT). Based on HPLC analyses, catechin was the most abundant compound identified (25.89?mg/g) for all accessions. Additionally, significant correlations among different antioxidant assays were found. With the high amount of total phenolic content, antioxidant capacity and antioxidant enzymes activity, seeds of P6, P7 and P8 accessions might be evaluated as a nutritional supplement.     

白灵菇多糖对力竭运动大鼠抗疲劳及抗氧化作用探析

为探究白灵菇多糖对力竭运动大鼠抗疲劳和抗氧化作用,选取250只Wistar雄性大鼠,采用随机数字表法平均分成5组,使其进行为期30 d跑台运动,观察白灵菇多糖对大鼠抗氧化能力的影响及对大鼠NO-NOS、ATPase活性的影响。在使用白灵菇多糖后,大鼠机体的谷胱甘肽过氧化物酶(GSH-Px)活力、SOD活力与-SH含量明显升高,丙二醛(MDA)水平显著降低;休息12 h后,大鼠机体的一氧化氮合酶(NOS)能力、一氧化氮(NO)水平与运动前水平一致,因此,白灵菇多糖能够增强机体抗氧化能力,并且能够增强机体的恢复能力。     

Moderate hypothermia post hypoxia-ischemia improves the cerebral energy metabolism in the immature rats

AIM: To study the effect of moderate hypothermia on immature rats with hypoxic-ischimic brain damage (HIBD). METHODS: The rats with HIBD were divided into normothermic recovered group (IN) and moderate-hypothermic recovered group (IH). Sham-operated rat pups were normothermic control group (NC) and moderate-hypothermic control group (HC). 0, 2, 6, 24, 48, 72 h after the end of hypoxic-ischemic (HI) insult, the brain was homogenized for measuring glucose and ATP, brain mitochondria was extracted for SDH activity, complex II activity and the capacity of ATP synthesization. RESULTS: In IN group, the brain glucose was significantly lower at 0 h, and recovered as normal at 2 h. The brain ATP and brain-mitochondrial SDH activities were firstly decreased at 2 h, 6 h and then recovered gradually, it was at it's peak value at 72 h. Brain-mitochondrial complex II activity and the capacity of ATP synthesis were recovered at 2 h, but they decreased again at 6 h and came to normal level at 72 h. In moderate-hypothermic group, all the indexes were significantly higher at all the time point than that in IN groups. CONCLUSION: Moderate hypothermia inhibits the decrease in the mitochondrial SDH activity, mitochondrial complex II activity and the capacity of ATP synthesis, increases the brain ATP concentration, improves the energy metabolism, and then protects the brain tissue.     

Establishment and characteristics of hybrid embryonic stem cell lines from blastocysts of the (C57BL/6J×129/J)F1 mouse

AIM: To establish hybrid mouse embryonic stem (ES) cell line from blastocysts of the (C57BL/6J×129/J) F1 mouse. METHODS: 3.5 days post-coitus (d.p.c.) blastocysts were cultured on mouse embryonic fibroblasts (MEFs) in the medium, after 3-4 days, Inner cell mass were picked up and disaggregated, then reseeded. After the ES-like colonies appeared, passaged them to give permanent ES cell lines. The pluripotent properties of ES cells obtained were analyzed by alkaline phosphatase (AKP) activity, expression of SSEA-1 and Oct-4, and their capacity to form teratoma. RESULTS: Two hybrid ES cell lines, SC1001, SC1002 were obtained from blastocysts of the (C57BL/6J×129/J) F1 genotype. Most of these ES cells had a normal karyotype and an XY sex chromosome composition. The pluripotent properties of the cell lines were analyzed on the basis of their alkaline phosphatase activity, expression of SSEA-1 and Oct-4, and their capacity to form teratoma in severe combined immunodeficiency (SCID) mice. CONCLUSION: Two hybrid mouse ES cell lines having pluripotent properties and capacity for long-term self renewal were generated from blastocysts of the (C57BL/6J×129/J) F1 genotype.     

亚硫酸氢钠对白菜叶片硝酸盐还原及光合能力的影响

 对日光温室内栽培的五叶一心白菜分别叶面喷施2、5、10 和15 mmol · L^-1 亚硫酸氢钠（NaHSO3）,以喷施清水为对照,分别在处理后0、4、8、12 和16 d 测定植株生物量、叶片的硝酸盐含量（NO₃^-）和硝酸还原酶（Nitrate reductase,NR）活性,同时测定叶片的光合参数和叶绿素荧光参数。结果表明,10 mmol · L^-1 NaHSO₃ 处理后12 d 时的效应最为显著,与对照相比,叶片NO₃^-含量降低44.85%,NR 活性提高51.26%,且株高和地上部干质量均明显增加;同时显著提高其净光合速率（P_n）、羧化效率（CE）、最大羧化速率（V_cmax）、PSⅡ的原初量子效率（Q）和最大电子传递速率（ETR_max）。由此说明,对白菜叶面喷施NaHSO3,一方面能够在一定程度上提高NR 活性,拉动氮素的还原同化,降低NO3-的累积;另一方面能够通过提高PSⅡ电子传递能力和羧化反应速率,促进光合碳同化效率,可在碳骨架和能量供应上拉动氮代谢的还原同化。     

The immunity effect of B7-H1 blockade on immature dendritic cells

AIM: To investigate the immune stimulation capacity of B7-H1 blockade on immature dendritic cells (DCs) in vitro. METHODS: The human monocyte-derived dendritic cells were induced in the presence of cytokine GM-CSF and IL-4. The expression of B7-H1 was detected by FCM. On blockade of B7-H1, the maturation and endocytic activity, T cells stimulatory proliferation capacity, IL-12 production, T cell differentiation effect of DCs were detected by FCM, MTT assay, ELISA and ELISPOT, respectively. RESULTS: The expression of B7-H1 was increased with the induction of DCs. On day 7, the positive expression was 54.12%, and the TNF-α induced mature DCs had the positive expression rate of 83.64%. The blockade of B7-H1 on immature DCs had sharply increased their T cells stimulatory proliferation capacity and IL-12 production, and efficiently induced the development of Th1/Tc1 cells, but had no effect on their maturation and endocytic activity. CONCLUSION: The blockade of B7-H1 on immature DCs increases its immune stimulation activity. It is valuable to investigate the antitumor immune responses of DCs vaccine with B7-H1 blockade.     

点柄粘盖牛肝菌粗多糖体外抗氧化活性的研究

研究点柄粘盖牛肝菌子实体多糖的抗氧化活性.结果显示,随着多糖浓度的上升,还原能力不断增强,对·O2-和·OH的清除效果也在加强,但多糖浓度更大时,清除率增强效果不明显,点柄粘盖牛肝菌子实体粗多糖对·OH的清除能力较强,多糖浓度为0.2 mg·mL-1时对·OH清除率最大,为98.95％;但对·O2-的清除作用不明显,多糖浓度为10mg·mL-1时清除率为21.68％.提取的点柄粘盖牛肝菌子实体粗多糖具有抗氧化活性,且活性呈现剂量效应.     

干燥方式对树莓总酚、总黄酮含量及其体外抗氧化活性的影响

以树莓为试验材料,采用自然干燥、红外干燥、热风恒温干燥和真空冷冻干燥4种干燥方式处理树莓,超声波辅助提取法提取树莓样品中的总酚和总黄酮含量,体外DPPH·和ABTS^+·的清除能力,拓展树莓加工产品方式,提高树莓干燥效率和品质。结果表明:干燥处理后样品中总酚、总黄酮含量及对ABTS^+·和DPPH·清除能力不同程度降低,其中真空冷冻干燥样品总酚和总黄酮含量损失最少,分别为(2.47±0.29)mg·g^-1和(2.06±0.61)mg·g^-1,ABTS^+·和DPPH·清除能力最大,其IC50分别为(4.53±0.04)mg·mL^-1和(5.17±0.12)mg·mL^-1;真空冷冻干燥方式最适宜于树莓的干燥。     

Phytochemical accumulation and antioxidant capacity at four maturity stages of cranberry fruit

Specific components of cranberry fruit are being associated with human health attributes, such as maintenance of urinary tract health and antioxidant status. Some of the chemical properties and antioxidant capacity of cranberry (Vaccinium macrocarpon Ait. cv. Pilgrim) fruits were investigated at light green, blush, light red and dark red maturation stages. Fruit total phenolics, total monomeric anthocyanins, soluble solids, titratable acidity and individual organic acids were examined. Antioxidant capacity of fruits were determined by both the ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC) assays. The fruit color was measured using a portable chromameter. A converse relationship was found between total phenolics and anthocyanin as fruits mature. Total phenolic concentration was declined from 7990 to 4745 mg GAE/kg fw, while total monomeric anthocyanin content was increased from 0.8 to 111.0 mg/kg fw from green to dark red stage. Brix was increased from 6 to 9.3% as well. The main organic acid was citric acid determined by the HPLC method. The antioxidant capacity of cranberries decreased to light red stage; when a fruit accumulates more anthocyanin the activity increased again in both FRAP and TEAC methods. Averaged antioxidant capacity measured was 12.61 and 17.48 mmol TE/kg fw by FRAP and TEAC methods.     

Bamboo NiR gene is associated with regeneration capacity

It was reported that the activity of NiR (nitrite reductase) enzyme encoded by the NiR gene was correlated with the regeneration ability in rice. To testify the function of NiR gene in bamboo, seven bamboo species whose calli had different differentiation rate were chosen to analyse their NiR enzyme activity. The results showed that bamboo NiR enzymatic activity had a certain correlation with the regeneration capacity. A NiR gene named DhNiR from Dendrocalamus hamiltonii with high regeneration capacity was cloned. Sequence analysis revealed that the ORF of DhNiR was 1779bp encoding 592 amino acids. Overexpression of DhNiR in rice reduced the time of shoot differentiation and increased the transformation rate, suggesting that DhNiR might play an important role in the regeneration ability of bamboo, and can be applied in regeneration and gene transformation of bamboo and other plant species.