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食用菌复合多糖的抗氧化活性研究 总被引：2，自引：0，他引：2
摘要：通过采用化学法，分别测定了猴头菇多糖、香菇多糖、银耳多糖、鸡腿菇多糖、灰树花多糖及香菇复合多糖、灰树花复合多糖体外抗氧化活性。结果表明，0．5mg·mL-1的猴头菇多糖、香菇多糖、银耳多糖、鸡腿菇多糖、灰树花多糖与复合多糖能够不同程度地清除DPPH·自由基、羟自由基（·OH）和超氧阴离子自由基．（02-·）能力，具有较好的抗氧化活性，而香菇复合多糖和灰树花复合多糖的总体抗氧化活性优于其组成单糖，其中以灰树花复合多糖对自由基的清除能力最强，其清除率分别为（89．5±1-3）％、（62．4±0．6）％、（47．9±1．0）％。 相似文献
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丁宁 《柑桔与亚热带果树信息》2013,(1):57-57
据《果树学报》2012年第6期《秸秆腐熟物覆盖对板栗园土壤微生物、养分含量和产量的影响》（作者张桂玲等）报道，以玉米秸、水稻秸、小麦秸和棉花秸为覆盖材料，覆盖质量均为5．0kg·m2，以不覆盖为对照，利用田间试验研究了不同秸秆腐解物覆盖对板栗园土壤微生物数量、土壤养分含量及板栗产量影响的差异。结果表明，与对照相比， 相似文献
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以L135、香66、808、日大4株香菇菌株为试材,采用苯酚-硫酸法、滤纸片扩散法及分光光度计法,研究了香菇胞外多糖含量、抑菌活性和抗氧化活性的差异,以期为香菇药食资源开发提供参考依据.结果表明:L135、808、香66、日大4株香菇的胞外多糖含量分别为(2.82±0.02)(1.61±0.04)(1.85±0.03)(2.22±0.06)mg·mL-1.当多糖质量浓度达到1.0mg·mL-1时,菌株香66的还原能力最强,菌株日大的ABTS+自由基清除率最高,其清除率为39.97％;菌株L135的DPPH自由基清除率最高,其EC50 值为3.53 mg·mL-1;菌株808的对羟自由基清除能力和抑菌活性最强. 相似文献
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洛巴伊大口蘑对栽培基质的降解及其相关胞外酶活性变化 总被引：1，自引：0，他引：1
以洛巴伊大口蘑为试材,采用袋栽方法,测定了洛巴伊大口蘑在棉籽壳培养基上生长期间栽培基质的降解及其相关胞外酶活性变化,以了解洛巴伊大口蘑对碳源的降解利用特点。结果表明:洛巴伊大口蘑具有完整的胞外纤维素酶系;淀粉酶在菌丝生长阶段活性较高;羧甲纤维素酶、滤纸纤维素酶和半纤维素酶的活性与纤维素和半纤维素的降解速率呈正相关,但β?葡萄糖苷酶活性与纤维素的降解速率没有相关性,漆酶和过氧化物酶活性与木质素的降解速率没有相关性;洛巴伊大口蘑具有很强的木质素降解能力,属于白腐菌;非木质纤维素主要在菌丝生长阶段被利用,木质纤维素是子实体生长发育阶段的主要碳源;在107d的栽培过程中,培养基失重52.40%,其中呼吸消耗43.98%,子实体转化率为8.42%。 相似文献
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本文测定了温度对香菇胞外纤维素酶和半纤维素酶活性的影响。木屑基质培养90天的香菇胞外游纸纤维素酶（C_1酶）、羧甲基纤维素酶（C_X酶）和半纤维素酶（H_C酶）的最适作用温度分别是55℃、55～60℃和50℃。在50～55℃条件下保温1小时后,C_1酶和H_C酶活性大幅度下降,而C_x酶活性下降较为缓慢,具有较高的热稳定性。本文提出相对活力系数（Relative activity coefficient,RAC）作为表示香菇菌丝生长温度与酶最适作用温度之间关系的一个参数。 相似文献
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白腐菌混合培养在胞外漆酶分泌上的种属互惠性 总被引：8，自引：0，他引：8
香菇、平菇、灵芝既是著名的食用菌 ,也是研究得相当广泛的白腐菌。香菇A3、平菇B2、灵芝KG菌株间两两混合培养 ,在胞外漆酶分泌状况上表现了较好的种属互惠性。研究结果显示 :A3 B2、B2 KG的混合培养体系表现了漆酶峰值提高、峰面积增大的优势 ,其中峰值情况为A3第 12d达 2 0 0单位 /g ,B2第 6d达 6 0 6单位 /g、KG第 10d达 5 76单位 /g ,A3 B2第 8d达 72 8单位 /g、B2 KG第 12d达 2 16 5单位 /g ;A3 KG的混合培养也在后、末期表现优于相应单株纯培养的漆酶状况。实验表明 ,不同种属白腐菌株混合培养对体系的漆酶分泌存在重要影响。 相似文献
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茯苓木腐特点的研究 总被引：1，自引：0，他引：1
测定了茯苓在松木屑-麦麸基物上生长期间,基物失重及木质纤维素的降解和有关酶活性的变化规律。实验结果表明: 1.茯苓菌分解木屑的能力较强。培养100天时,呼吸作用消耗掉的有机质达38～39％,基物中纤维素降解了46.32％,半纤维素降解了58.41％,但木素降解量极低。由此可见,茯苓菌主要是利用植物体中的纤维素和半纤维素,是一种褐腐型木材腐朽菌。 2.茯苓降解松木屑具有一定的阶段性。0—45天期间呼吸消耗的基物有机质和纤维素,半纤维素的降解量较多,在基物中茯苓菌核类物质开始产生时(45天左右),纤维素和半纤维素降解速率明显下降,呼吸强度也明显降低。 3.茯苓在生长发育过程中能向基物中释放胞外CMC酶、FP酶、木聚糖酶和淀粉酶。初期酶活性较低,在菌丝体向胞外释放菌核类物质时,4种酶活性明显上升,直到培养100天酶活性仍处于高峰水平。 相似文献
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利用废菌筒栽培双孢蘑菇高产技术初报 总被引：1，自引：0，他引：1
德化县常年栽培香菇、平菇等木腐菌类600万袋以上，栽培后留下大量的废菌筒，这些废菌筒的木质纤维经木生菌分解后得到降解，含有丰富的氮、磷、钾等营养元素，是极好的草生菌栽培原料。笔者组织菇农以废菌筒、稻草和牛粪为主要材料，栽培双孢蘑菇560m^2，平均产鲜菇9．6kg／m^2，比我县常规栽培平均产量增产1．4kg／m^2，节省成本1．2元/m^2，取得良好的经济效益和社会效益。现将该技术总结如下。 相似文献
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AIM: Although endovascular radiotherapy inhibits neointimal hyperplasia, the exact alterations induced by β-particles irradiation remain to be elucidated. The objective of this study was to investigate the ability and the cellular mechanism of local β-particles emission from 188Re to inhibit vascular smooth muscle cells (SMCs). METHODS: The SMCs in vitro were irradiated by 188Re with single doses of 2.6 Gy-25.8 Gy. The effects of β-particles on SMCs, such as effective irradiate doses, the period of inhibition for SMCs proliferation, the changes of cell proliferation rate and DNA synthesis rate, cell cycle progression and related gene expression, were investigated by cell count, [3H]-TdR incorporation, cell cycle progression analysis, cell viability and immunocytochemistry, respectivecy. RESULTS: β-particles irradiation with dose of 5.2 Gy could inhibit significantly SMCs proliferation. At dose of 20.6 Gy DNA synthesis inhibitory rate was 92%, SMCs proliferation rate was only 3%. Renoval of 188Re did not abolish the inhibitory effects of β-particles on SMCs proliferation. The expression of P53 was up regulation and PCNA was down regulation after irradiation. CONCLUSION: β-particles from 188 Re was significantly effective and permanent in inhibiting SMCs proliferation, and inhibitory effect was in dose-dependet manner ED50was 5 Gy, the best dose to inhibit SMCs proliferation was 20 Gy. β-particles irradiation induced SMCs to occur G0/G1 arrest, damaged the ability of SMCs reproliferation and led to cell clonogenic death. P53 and PCNA had regulatiory effects on SMCs proliferation after β-particles irradiation. 相似文献
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AIM:To study the effect of L-Arg on plasma content of endothelin (ET) and the expression of proto-oncogene c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy. METHODS: The level of c-fos mRNA were measured by in situ hybridization. The ET in plasma were measured by radioimmunoassay. RESULTS:After eight weeks of treatment with L-Arg, the expression of c-fos decreased markedly (P＜0.01). The ET content in plasma also decreased significantly by L-Arg(P＜0.01).CONCLUSION: Plasma ET content and the expression of c-fos in the left ventricle of rats with renovascular hypertensive hypertrophy could be decreased by L-Arg administration. 相似文献
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《International Journal of Fruit Science》2013,13(3):101-120
Abstract Saskatoon berry (Amelanchier alnifolia Nutt., Rosaceae) and blueberry (Vaccinium corymbosum L., Ericaceae) are substantially equivalent in all characteristics that are important to the consumer, including fruit color, shape, size, nutrition, texture, and uses. In addition, both fruits are native to North America and they have practically identical historical uses and known health benefits. Their composition, processing, nutritional value and metabolism, intended uses, and levels of undesirable substances are compared. 相似文献
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多效唑对猕猴桃离体试管苗生长及内源激素的影响 总被引：18，自引：0，他引：18
多效唑（ＰＰ３３３）处理猕猴桃试管苗，降低了其生长强度；植株体内的ＧＡ３、ＩＡＡ和ＺＴ含量下降，ＡＢＡ的含量上升，乙烯释放率增加；并且能降低外源的ＧＡ３和ＩＡＡ促进生长的作用，而外源的ＧＡ３和ＩＡＡ又能不同程度地逆转多效唑的抑制作用，使植株恢复生长。 相似文献
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HU Zhi-cheng ZHU Jia-yuan ZHU Bin GUO Dong CHEN Bin ZHANG Kai HU Kun-hua LI Ming-tao TANG Bing 《园艺学报》2011,27(9):1802-1806
AIM: To investigate and screen the sensitive proteins in the formation mechanism of pathological scars by comparing the results of differential proteomic analysis between pathological scars and normal skin.METHODS: Two-dimensional gel electrophoresis was used to detect the protein expression profiles in 8 keloid patients, 8 hypertrophic scar patients and 3 matched normal skin patients.The proteins that showed differential expression of over 4-fold change were cut and analyzed by MALDI-TOF/TOF mass spectrometry.RESULTS: A two-dimensional protein profiling comparison between pathological scars and normal skin was successfully established.On average, 2 978 spots in keloid, 2 975 spots in hypertrophic scar and 3 053 spots in normal skin were identified using gel analysis software.Compared with normal skin, there were totally 36 differentially-expressed proteins in keloid and hypertrophic scar identified from the spots of over 4-fold change, including 16 proteins in both keloid and hypertrophic scar (8 up-regulated and 8 down-regulated), 11 only in keloid (9 up-regulated and 2 down-regulated) and 9 only in hypertrophic scar (4 up-regulated and 5 down-regulated).CONCLUSION: Proteomic analysis can identify the proteins with variance of pathological scars versus normal skin, thus providing probable new clues to reveal the formation mechanism of pathological scars. 相似文献
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The objective of this study was to establish a cryopreservation protocol for hawthorn shoot apices (Crataegus pinnatifida Bge.). Cryopreservation was carried out via encapsulation–dehydration, vitrification, and encapsulation–vitrification on shoot apices excised from in vitro cultures. We began by showing that cold-acclimation enhanced the regrowth of cryopreserved apices from 10.0 to 65.5% in encapsulation–dehydration. We then decided that the encapsulation–dehydration method was an optimal cryopreservation method for hawthorn shoot apices in terms of its high recovery after cryopreservation as well as its ease of use compared with vitrification and encapsulation–vitrification. In encapsulation–dehydration, the protocol leading to optimal regrowth was as follows: after cold-acclimation at 5 °C in the dark for 2 weeks, excised shoot tips were pretreated for 24 h at 25 °C on hormone-free Murashige and Skoog [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue culture. Physiol. Plant. 15, 473–497] (MS) basal medium with 0.4 mol/L sucrose, then encapsulated and precultured in liquid MS medium with 0.8 mol/L sucrose for 16 h at 25 °C. Precultured beads were dehydrated for 6 h at 25 °C in the dessicator containing 50 g silica gel to a moisture content of 15.3% (fresh-weight basis) before cryostorage for 1 h. In addition, we examined the effect of adding glycerol to both the alginate beads and loading solution to enhance regrowth after cryopreservation in encapsulation–dehydration. In the present study, it was shown that adding 0.5 mol/L glycerol resulted in high regrowth percentages (82.5–90.0%) in four Crataegus species. 相似文献
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AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [3-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10-6-10-4 mmol/L) stimulated [3-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [3-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10-6-10-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl2 for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation. 相似文献
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Duncan Brean W. Boyle Shannon Breininger David R. Schmalzer Paul A. 《Landscape Ecology》1999,14(3):291-309
Historic landcover dynamics in a scrubby flatwoods (Tel-4) and scrub landscape (Happy Creek) on John F. Kennedy Space Center were measured using aerial images from 1943, 1951, 1958, 1969, 1979, and 1989. Landcover categories were mapped, digitized, geometrically registered, and overlaid in ARC/INFO. Both study sites have been influenced by various land use histories, including periods of range management, fire suppression, and fire management. Several analyses were performed to help understand the effects of past land management on the amount and spatial distribution of landcover within the study sites. A chi-squared analysis showed a significant difference between the frequency of landcover occurrence and management period. Markov chain models were used to project observed changes over a 100-year period; these showed current management practices being effective at Tel-4 (restoring historic landscape structure) and much less effective at Happy Creek. Documenting impacts of past management regimes on landcover has provided important insight into current landscape composition and will provide the basis for improving land management on Kennedy Space Center and elsewhere. 相似文献
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AIM: Previous studies performed with XBP-01 in vitro indicated that XBP-01 could inhibit vascular smooth muscle cells from being transformed into foam cell and could eliminate the atherosclerotic plaque in C57BL/6J mouse. This experiment is to investigate its mechanism of eliminating plaques in vitro. METHODS: The cultured porcine artery smooth muscle cells incubated with XBP-01 of 0.1 mg/L for 24 h after preincubated with oxidized low density lipoprotein of 15 mg/L for 72 h in vitro. The samples were analyzed by fluorescence microscope, confocal microscope system and flow cytometry. RESULTS: Apoptosis was triggered by being incubated with oxidized low density lipoprotein and this process was accelerated additionally by being incubated with XBP-01. CONCLUSION: XBP-01 can be effective in eliminating atherosclerotic plaque by accelerating the process in which oxidized low density lipoprotein induced smooth muscle cell apoptosis. 相似文献
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Species distribution models (SDMs) often use elevation as a surrogate for temperature or utilise elevation sensitive interpolations
from weather stations. These methods may be unsuitable at the landscape scale, especially where there are sparse weather stations,
dramatic variations in exposure or low elevational ranges. The goal of this study was to determine whether radiation, moisture
or a novel estimate of exposure could improve temperature estimates and SDMs for vegetation on the Illawarra Escarpment, near
Sydney, Australia. Forty temperature sensors were placed on the soil surface of an approximately 12,000 ha study site between
November 2004 and August 2006. Linear regression was used to determine the relationship with environmental factors. Elevation
was correlated more with moderate temperatures (winter maximums, summer minimums, spring and autumn averages) than extreme
temperatures (summer maximums, winter minimums). The correlation (r
2) between temperature and environmental factors was improved by up to 0.38 by incorporating exposure, moisture and radiation
in the regressions. Summer maximums and winter minimums were predominately determined by exposure to the NW and coastal influences
respectively, while exposure to the NE and SW was important during other seasons. These directions correspond with the winds
that are most influential in the study area. The improved temperature estimates were used in Generalised Additive Models for
37 plant species. The deviance explained by most models was increased relative to elevation, especially for moist rainforest
species. It was concluded that improving the accuracy of seasonal temperature estimates could improve our ability to explain
the patchy distribution of many species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献