香菇子实体多糖分步酶解法提取研究

首先采用正交试验优化纤维素酶﹑果胶酶和木瓜蛋白酶对香菇(Lentinula edodes)子实体多糖酶解提取的工艺参数,然后在优化酶解条件下,依次采用纤维素酶﹑果胶酶和木瓜蛋白酶分步处理香菇子实体以提取香菇多糖,并与单一酶解提取法和传统热水浸提法进行对比.结果表明,纤维素酶﹑果胶酶﹑木瓜蛋白酶的最佳提取工艺参数依次为加酶量0.8%、温度45 ℃、pH 4.5、提取时间1 h,加酶量1.0%、温度45 ℃、pH 3.5、提取时间2.0 h和加酶量1.0%、温度45 ℃、pH 4.0、提取时间1.5 h;在优化提取条件下,分步酶解法提取香菇粗多糖的提取率可达14.17%,比传统热水浸提法提高128.2%,比单独采用纤维素酶﹑果胶酶﹑木瓜蛋白酶酶解提取分别提高了43.71%、46.99%和23.11%.紫外光谱分析表明,分步酶解法提取的香菇多糖纯度明显高于热水浸提法提取的香菇多糖.-     

枸骨叶抑菌物质的提取及抑菌作用研究

采用正交试验法探讨枸骨叶抑菌物质的最佳提取条件,以杯碟法对枸骨叶提取物进行体外抗菌作用以及pH、温度、时间因素对其抗菌活性的影响。结果表明:枸骨叶抑菌物质的最佳提取条件为:以乙酸乙酯为溶剂,提取温度为40℃,料液比为1∶10,浸提时间为2.5 h;枸骨叶提取物对金色葡萄球菌、枯草杆菌、大肠杆菌都有明显的抑菌效果,最低抑菌浓度分别为0.0625、0.50、.5 mg/mL;最小杀菌浓度为0.1251、0、.5 mg/mL。该物质抑菌pH范围为7~9,热稳定性较差,最佳抑菌时间为24 h。     

混合酶提法提取铁皮石斛中石斛多糖的优化工艺研究

以铁皮石斛为试材,采用纤维素酶与果胶酶的等量混合提取法,通过单因素试验与正交实验,研究了pH值、酶浓度、酶解时间、酶解温度等因素对石斛多糖提取效率的影响。结果表明:铁皮石斛多糖提取最佳工艺为pH 6.5、1%浓度的纤维素酶和果胶酶1∶1等量混合、50℃下提取135min,在此条件下石斛多糖提取率为41.33%;说明该工艺是可行的,且具有较高的提取率。     

纤维素酶果胶酶辅助提取西瓜番茄红素工艺优化

本试验以质量比为4:1的纤维素酶、果胶酶组成的复合酶辅助提取西瓜番茄红素,分析了纤维素酶、果胶酶的最佳提取条件,分析了纤维素酶、果胶酶的最佳作用条件,采用正交试验优化了纤维素酶、果胶酶辅助提取西瓜番茄红素的工艺。结果得出,提取西瓜番茄红素最佳工艺为添加复合酶(维素酶:果胶酶=4:1)至西瓜糊(0.60%,w/w),调节体系pH值为4.5,55℃下酶解2.0 h;采用乙酸乙酯-丙酮混合溶剂(7:1,V/V)提取,提取率91%,提取效果较好。     

籽瓜总皂苷的提取工艺研究

以籽瓜为试材,通过乙醇回流法、超声法、超声纤维素酶法、超声果胶酶法提取籽瓜总皂苷,并采用4因素3水平正交实验设计对超声纤维素酶法提取工艺进行优选,以籽瓜提取液中总皂苷的含量和提取物得率为指标,优选最佳提取工艺。结果表明:纤维素酶用量为10U/g,pH 4.5,酶解温度为45℃,酶反应时间为120min为籽瓜总皂苷提取的最佳工艺条件。籽瓜提取物得率为61.32%,籽瓜总皂苷的含量为5.03%,该试验操作简单,工艺条件稳定。     

纤维素酶解复合碱提酸沉法提取杏鲍菇蛋白质

为提高杏鲍菇(Pleurotus eryngii)蛋白质的提取率,本试验采用纤维素酶解复合碱提酸沉法进行提取,以料液比、酶的添加量、反应时间和温度为因素进行单因素试验,蛋白质提取率为响应值,利用Box-Behnken进行响应面优化纤维素酶解条件,与单一碱提酸沉法提取蛋白质后的提取率进行比较。试验结果表明,纤维素酶解最佳工艺条件为:料液比1:55,温度40℃,时间100 min,酶的添加量1.5%,复合碱提酸沉后蛋白质提取率为51.36%,显著高于碱提酸沉法的45.89%。因此,纤维素酶复合碱提酸沉法提取杏鲍菇蛋白质优于碱提酸沉法。     

酶解工艺对籽瓜浓缩汁出汁率的影响

以籽瓜为试验材料,利用果胶酶和纤维素酶进行酶解。通过单因素和正交试验确定籽瓜的最佳酶解工艺:果胶酶0.1%,纤维素酶0.05%,酶解温度45℃,酶解时间2h,酶解p H=4.5。在此最佳酶解条件下,出汁率达86.3%。     

双酶法提取角瓜籽仁蛋白质的工艺研究

以角瓜籽为试材,采用超声波进行预处理,选取纤维素酶和Alcalase碱性蛋白酶以2∶1比例复配为复合酶制剂,研究了双酶法提取角瓜籽仁蛋白质的最佳工艺条件。结果表明:角瓜籽仁蛋白质的最佳提取工艺为:料液比1∶20g/mL、总加酶量7%、酶解温度55℃、酶解时间120min,酶解pH 7.5,在此条件下角瓜籽仁蛋白质的提取率最高,为74.2%。     

酶法提取刺玫果总黄酮工艺研究

以刺玫果为试材,采用酶法辅助提取刺玫果总黄酮,研究各因素对刺玫果总黄酮提取率的影响。结果表明:纤维素酶辅助提取刺玫果总黄酮的最佳工艺条件为提取溶剂为50%乙醇、温度控制在50℃、料液比1∶15g/mL、纤维素酶加入量为40mg/g、控制提取液于pH 5.5条件下,酶解提取2次,每次140min,在最佳条件下进行3次验证试验,其总黄酮提取率平均为95.94mg/g。     

酶法提取云南萝芙木中阿吗碱的研究

研究3种纤维素酶法提取云南萝芙木中阿吗碱的最佳工艺。结果表明:酶解最适条件为:pH 5.0,酶用量5 mg/5g,时间2 h,温度50℃;酶解处理后的阿吗碱提取率比直接用甲醇提取提高了29.3%;说明酶解处理更有利于阿吗碱的提取。     

Effects of radiation from 188Re on smooth muscle cell proliferation

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.     

Effect of L-Arg on plasma content of endothelin and expression of c-fos mRNA in the left ventricle of rats with renovascular hypertensive hypertrophy

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.     

多效唑对猕猴桃离体试管苗生长及内源激素的影响

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。     

Proteomic analysis between pathological scars and normal skin

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.     

Compositional and Functional Properties of Saskatoon Berry and Blueberry

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.     

Cryopreservation of shoot apices of hawthorn in vitro cultures originating from East Asia

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.     

Coupling past management practice and historic landscape change on John F. Kennedy Space Center,Florida

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.     

Metallothionein inhibits homocysteine-induced proliferation of rat vascular smooth muscle cells

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.     

XBP-01 accelerated apoptosis induced by oxidized low density lipoprotein in vascular smooth muscle cells

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.     

The effect of exposure on landscape scale soil surface temperatures and species distribution models

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.