经酿酒发酵后葡萄籽中原花青素提取工艺优化

以葡萄发酵后的葡萄籽粉碎物为试材,采用浸提方法,研究了浸提温度、时间、料液比、乙醇浓度对发酵后葡萄籽中原花青素提取率的影响。结果表明:4个因素的影响顺序为料液比提取温度提取时间乙醇浓度。原花青素提取工艺的最佳条件为提取温度为40℃、提取时间为90min、料液比为1∶28g/mL、乙醇浓度为60%,提取率为3.05%。     

热浸提“紫罗兰”紫薯花青素的工艺条件优化研究

以"紫罗兰"紫薯为试材,采用正交实验方法,研究了热浸提过程中温度、提取剂比例、料液比和提取时间对紫薯中花青素提取率的影响。结果表明:温度是对花青素提取效果影响最大的因素,最佳的提取条件是温度55℃,提取剂为95%乙醇和0.1%HCl溶液比例50∶50,料液比1∶2g/mL,提取时间4.5h。     

正交实验优化紫叶甘蓝型油菜花色苷提取工艺

以紫叶甘蓝型油菜为试材,采用正交实验设计方法,研究提取温度、提取剂种类、提取时间、料液比等对紫叶甘蓝型油菜花色苷提取率的影响,同时建立最佳提取工艺。结果表明:影响紫叶甘蓝型油菜花色苷提取率的因素依次为提取时间料液比提取温度提取剂种类,其最佳提取工艺为提取温度60℃,提取剂3%盐酸+90%乙醇,料液比1∶15g/mL、提取时间5h。     

莲子心总黄酮的超声波萃取工艺研究

以莲子心为试材,乙醇溶液为提取剂,采用超声波萃取法,进行单因素试验和L9(34)正交实验,研究乙醇浓度、提取时间、料液比和提取温度对总黄酮提取率的影响。结果表明:影响莲子心中总黄酮提取率的主要因素是乙醇浓度,其次依次为提取温度、料液比、超声波萃取时间;提取的最佳条件为:乙醇浓度60%,提取温度70℃,料液比1∶24g/mL,超声波萃取时间30min,该条件下得到的总黄酮的提取率为10.86mg/g。     

响应面优化超声波辅助太行菊总黄酮提取工艺

以太行菊为试材,以超声波辅助提取试验,采用单因素分析和响应面分析相结合的方法,筛选出最优的太行菊黄酮提取组合配置,针对太行菊黄酮类化合物提取工艺进行优化。结果表明:单因素试验中最佳的料液比1∶25g·mL~(-1),乙醇浓度60%,提取温度60℃,提取时间45min。响应面试验的方差分析表明,料液比、乙醇浓度和提取温度对黄酮提取率影响差异极显著,提取时间对提取率的影响差异不显著。4个因素对提取率的影响依次为料液比乙醇浓度提取温度提取时间。回归方程模型预测的最优提取工艺条件为料液比1∶25.88g·mL~(-1)、乙醇浓度61.78%、提取温度63.44℃、提取时间55min,太行菊黄酮提取率可达极值4.74%。料液比、乙醇浓度和提取温度的增加极显著的提高了太行菊黄酮的提取率。     

水提法同步提取分离香菇中蛋白质和多糖的工艺研究

通过水提法同步提取分离香菇中的蛋白质和多糖,采用单因素实验研究料液比、提取温度、提取时间与蛋白质和多糖提取率的关系,并通过正交实验优化工艺条件。结果为,影响蛋白质提取率的主次因素为提取温度料液比提取时间;影响多糖提取率的主次因素为料液比提取温度提取时间。综合分析得到提取的最佳工艺组合为料液比20、提取温度100℃、提取时间3.5 h(二次提取)。该组合下蛋白质提取率为6.90%,多糖提取率达38.50%。     

超声波法提取紫薯花青素的工艺研究

花青素具有防癌抗癌、保肝、降压、改善视力、延缓衰老等多种保健功能,作为一种功能性天然色素已引起越来越多的关注。本文采用超声波法对紫薯中的花青素进行提取,通过单因素试验探讨了不同料液比、提取剂浓度、浸提温度、浸提时间对紫薯花青素提取效果的影响。通过正交试验得到最佳提取条件为物料比1：30,提取剂浓度5%,浸提温度60℃,超声时间为30min。     

牡丹花黄酮的超声辅助提取工艺研究

为了研究牡丹花黄酮的提取工艺,本试验采用超声波辅助法提取牡丹花黄酮,考察了乙醇浓度、提取温度、提取时间和料液比对黄酮提取率的影响。在单因素试验的基础上,采用正交试验对牡丹花黄酮的提取工艺进行了优化,结果表明,四种因素对提取率的影响顺序依次为料液比提取时间提取温度乙醇浓度;最佳的提取条件为乙醇浓度50%、提取温度60℃、提取时间40 min、料液比1:40。在此条件下黄酮提取率达到2.998%,比传统浸提法(1.93%)提高了1.068%。     

黑米麸皮中花青素的提取工艺及抑菌活性研究

以黑米为原料,通过超声波方式提取黑米麸皮中花青素浸提液。以提取率为指标,根据单因素和正交试验确定最优工艺参数,再以不同浓度的黑米麸皮中粗提物来测定对红色毛廯菌的抑菌性。结果表明,影响黑米麸皮中花青素的提取率因素主要顺序为:提取温度提取时间料液比,通过正交设计优化并修正的最佳条件为提取温度30℃、提取时间30min、料液比为(g/m L)1︰10。其中温度对黑米花青素的提取率的影响效果显著;不同浓度黑米麸皮的粗提物对红色毛廯菌的抑制效果比较好,浓度为80.0mg/m L时,其抑制率在45.4%以上,对菌丝生长的EC50为4.3964mg/m L,且随着浓度的增加,抑菌活性逐渐增强。     

响应面法优化超声提取锁阳多糖工艺研究

为探讨在超声波作用下锁阳多糖提取的工艺条件,以锁阳为原料,在单因素试验基础上,采用响应面法研究了超声提取时间、液料比和提取温度对锁阳多糖提取率的影响。结果表明:提取时间和液料比对多糖提取率均有显著影响,提取温度影响不显著;优化出锁阳多糖超声提取工艺条件为提取温度97.62℃,液料比7.75∶1、提取时间85.57 min,在此条件下锁阳多糖的理论提取率为23.1%。与传统水浸法提取相比,超声提取锁阳多糖具有明显的优势,提取时间较短,液料比和温度较低,以及较高的提取率等。     

Relationship between renal hypertension and cardiac α1-adrenoceptor autoantibodies in rats

AIM: To examine the autoantibody against α₁-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α₁-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α₁-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α₁-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.     

Influence of Mineral Nutrients on Strawberry Fruit Quality and Their Accumulation in Plant Organs

Abstract

This review is based partly on complete articles and partly on abstracts. Three of the 60 articles deal with the total uptake of elements in strawberry plant organs in two different strawberry production systems, both considered as optimal concerning amount and balance of elements. The effect on fruit quality may be dramatic if the level of a particular element is outside this range, but there may also be effects initiated by differences within the optimal range of elements. Most articles refer to product oriented quality, but some focus on consumer oriented quality, as discussed by Shewfelt (1999). The discussion here is on a general basis, so one should keep in mind that there are cultivar differences and that specification of nutrition ideally should mirror the needs of a single cultivar, or a group of cultivars with similar requirements. Also, to get a complete understanding of the subject future reviews should embrace a broader access of information including the effect on plant development of individual elements, such as the role of calcium in fruit firmness and its importance in cell wall structure. However, the intention here is to narrow the information to results that suggest a direct connection between nutrient uptake and fruit quality.     

Mixed-severity fire regime in a high-elevation forest of Grand Canyon,Arizona, USA

Fire regime characteristics of high-elevation forests on the North Rim of the Grand Canyon, Arizona, were reconstructed from fire scar analysis, remote sensing, tree age, and forest structure measurements, a first attempt at detailed reconstruction of the transition from surface to stand-replacing fire patterns in the Southwest. Tree densities and fire-/non-fire-initiated groups were highly mixed over the landscape, so distinct fire-created stands could not be delineated from satellite imagery or the oldest available aerial photos. Surface fires were common from 1700 to 1879 in the 4,400 ha site, especially on S and W aspects. Fire dates frequently coincided with fire dates measured at study sites at lower elevation, suggesting that pre-1880 fire sizes may have been very large. Large fires, those scarring 25% or more of the sample trees, were relatively infrequent, averaging 31 years between burns. Four of the five major regional fire years occurred in the 1700s, followed by a 94-year gap until 1879. Fires typically occurred in significantly dry years (Palmer Drought Stress Index), with severe drought in major regional fire years. Currently the forest is predominantly spruce-fir, mixed conifer, and aspen. In contrast, dendroecological reconstruction of past forest structure showed that the forest in 1880 was very open, corresponding closely with historical (1910) accounts of severe fires leaving partially denuded landscapes. Age structure and species composition were used to classify sampling points into fire-initiated and non-fire-initiated groups. Tree groups on nearly 60% of the plots were fire-initiated; the oldest such groups appeared to have originated after severe fires in 1782 or 1785. In 1880, all fire-initiated groups were less than 100 years old and nearly 25% of the groups were less than 20 years old. Non-fire-initiated groups were significantly older (oldest 262 years in 1880), dominated by ponderosa pine, Douglas-fir, or white fir, and occurred preferentially on S and W slopes. The mixed-severity fire regime, transitioning from lower-elevation surface fires to mixed surface and stand-replacing fire at higher elevations, appeared not to have been stable over the temporal and spatial scales of this study. Information about historical fire regime and forest structure is valuable for managers but the information is probably less specific and stable for high-elevation forests than for low-elevation ponderosa pine forests.This revised version was published online in May 2005 with corrections to the Cover Date.     

瓜叶绿素降解关键酶基因PPH和PAO cDNA片段的克隆与表达初步分析

 以西双版纳黄瓜和‘华黄5号’黄瓜叶片为试验材料,研究了衰老过程中两种黄瓜叶片叶绿素含量变化及脱镁叶绿素脱镁叶绿酸水解酶基因PPH和脱镁叶绿酸a加氧酶基因PAO的表达。结果表明：随着叶片衰老,叶绿素a和叶绿素b含量显著降低,叶绿素a与叶绿素b的比值在0.5左右,推测叶绿素b的含量可能对黄瓜叶片保绿起到重要作用。荧光定量RT-PCR分析结果显示：PPH和PAO在西双版纳黄瓜叶片生长35 d时表达量最高,分别为5.50和1.86;PPH在‘华黄5号’叶片35 d时表达量最高,为7.14,而PAO在35和45 d表达量都很高,分别为3.90和3.91;PPH和PAO在西双版纳黄瓜叶片中的表达量低于在‘华黄5号’中。     

Effects of simvastatin on PDGF-BB and serum-induced proliferation of vascular smooth muscle cells and on the expression of tumor suppressor gene PTEN

AIM:To observe the effect of simvastatin on the proliferation of vascular smooth muscle cells(VSMCs) induced by serum and growth factor PDGF-BB and the effect of simvastatin on the expression of PTEN,a important regulator of G₁/S cell cycle transition. METHODS:The DNA synthesis was determined by [³H]-TdR incorporation, cell cycle was examined with flow cytometry, the protein level of PTEN was measured by Western blot method. RESULTS: (1)Simvastatin inhibited [³H]-TdR incorporation in a dose dependent manner. (2) Flow cytometric DNA analysis revealed that simvastatin induced significantly enhancement of G₀/G₁ phase and decrease in S phase VSMCs.(3)Simvastatin increased protein level of PTEN and mevalonate, a metabolite of HMG-COA, reversed the effect of simvastatin on PTEN protein expression. CONCLUSION:Simvastatin may inhibit proliferation of VSMCs and retarded cell cycle in G₀/G₁ phase by increasing PTEN expression through inhibiting synthesis of mevalonate.     

Relationships of landscape,prey and agronomic variables to the abundance of generalist predators in cotton (<Emphasis Type="Italic">Gossypium hirsutum</Emphasis>) fields

A two-year field study investigated the possible effects of grain sorghum (Sorghum bicolor [L.] Moench) and uncultivated areas on the abundance of generalist predators in commercially-managed cotton (Gossypium hirsutum L.) fields in Texas, USA. From 63 to 70 fields were sampled for pests and predators over nine consecutive weeks during early stages of cotton development. Additional data on agronomic practices and landscape composition at three spatial scales were also collected for each field. Stepwise regression analyses were used to determine the relationships of landscape, agronomic and prey variables to the abundance of generalist predators. Because the variables most closely linked to predator levels could vary over time, separate regressions were conducted for three time periods corresponding to stages of grain sorghum growth (half-bloom, hard-dough, maturity) in each year. Significant relationships between predator abundance and agricultural landscape composition appear in both years and in all three time periods, but the specific relationships of landscape variables to cotton predator levels differed between and within years. At maturity in 2001, predator levels rose as the amount of uncultivated land from 1.6 to 3.2 km distant and the perimeter shared with grain sorghum increased. During 2002, the area of grain sorghum (half-bloom) and uncultivated land (hard-dough) within 1.6 km of cotton fields were both positively related to predator numbers. Cotton planting dates and the abundance of cotton fleahoppers (Pseudatomoscelis seriatus [Reuter]) were also strongly linked to predator numbers during both years. Results suggest that the total amount of grain sorghum or uncultivated land in an area is more important than the presence of these habitats adjacent to cotton fields, and that landscape composition may sometimes be the most important factor in determining predator abundance.     

Influence of lanthanum nitrate on the expression of aquaporin 7 in the testis of rats

AIM: To find out whether different dosage of rare earth element-lanthanum can influence the expression of aquaporin 7(AQP 7) in the testis of rats. METHODS:Rats were fed with lanthanum nitrate[La(NO₃)₃]and killed 6 months later.Testes were then removed immediately to extract total RNA.Northern blot analysis is performed finally. RESULTS:0.1 mg/kg La(NO₃)₃ depressed the expression of AQP 7 in rat testis, while 20 mg/kg La(NO₃)₃ had no significant effect on it. CONCLUSION: AQP 7 expession is found in the rat testis; La(NO₃)₃ can depress the expression of AQP 7 in the rat testis.     

Ergebnisse der Leistungsprüfung von Kirschensorten auf wuchsreduzierenden Unterlagen in Ungarn

Zusammenfassung In Ungarn gibt es ein reges Interesse an intensivem Obstanbau. Der Erfolg dieses Anbaus hängt in sehr großem Maße von den Wechselwirkungen zwischen dem Standort, den Sorten-Unterlagen-Kombinationen und dem Anbauverfahren ab.Um die Wirkung wuchsreduzierender Kirschenunterlagen aus ausländischen Züchtungsinstituten unter ungarischen Klimaverhältnissen untersuchen zu können, wurde im Forschungsinstitut für Obst- und Zierpflanzenbau Budapest-Érd ein Vergleichsversuch durchgeführt. Der Versuch wurde mit Cerasus avium C. 2493, Weiroot 13, Weiroot 53, Weiroot 72, Weiroot 154, Weiroot 158, GiSelA 5 und P-HL-A-Unterlagen 1997 in der Versuchsanstalt des Forschungsinstituts für Obst- und Zierpflanzenbau Budapest-Érd aufgepflanzt. Als Kontrolle diente die Sämlingsunterlage Cerasus mahaleb Cema, deren Anteil im ungarischen Süßkirschenanbau bei 70–80% liegt. Die Unterlagen wurden mit drei Süßkirschensorten (Germersdorfi , Linda, Katalin) und mit einer Sauerkirschensorte (Piramis) veredelt.Nach der Wüchsigkeit bis zum Ende des 8. Standjahres konnten die Unterlagen in drei Gruppen eingeteilt werden: starkwüchsige (Cerasus mahaleb Cema, Cerasus avium C. 2493, Weiroot 13), mittelstarkwüchsige (Weiroot 158, Weiroot 154, P-HL-A) und schwachwüchsige Unterlagen (Weiroot 72, Weiroot 53, GiSelA 5). Die stärkste Neigung, Wurzelschosse zu treiben, zeigten Weiroot 13 und Weiroot 154.Während der Untersuchung der generativen Eigenschaften wurde beobachtet, dass es Unterschiede in der Blütezeit der Sorten-Unterlagen-Kombinationen gibt. Auf GiSelA 5 veredelte Sorten blühten 1 oder 2 Tage früher als die Kontrolle. Es gab nur geringe Unterschiede in der Reifezeit der Kombinationen. Den größten Ertrag hatte die Sorte Linda, gefolgt von Katalin, Germersdorfi 3 und Piramis. Der größte Fruchtdurchmesser wurde bei der Süßkirschensorte Germersdorfi 3 gefunden, der größte Anteil an Früchten größer als 26 mm bei den Bäumen auf Weiroot 72 (23%), der geringste Anteil großer Früchte bei den Bäumen auf GiSelA 5. Bei Piramis wurde der größte Fruchtdurchmesser auf Cerasus avium C. 2493 gemessen.     

Effects of corridors on home range sizes and interpatch movements of three small mammal species

Corridors are predicted to benefit populations in patchy habitats bypromoting movement, which should increase population densities, gene flow, andrecolonization of extinct patch populations. However, few investigators haveconsidered use of the total landscape, particularly the possibility ofinterpatch movement through matrix habitat, by small mammals. This studycompares home range sizes of 3 species of small mammals, the cotton mouse(Peromyscus gossypinus), old-field mouse (P.polionotus) and cotton rat (Sigmodon hispidus)between patches with and without corridors. The study site was in S. Carolina,USA. Corridor presence did not have astatistically significant influence on average home range size. Habitatspecialization and sex influenced the probability of an individual movingbetween 2 patches without corridors. The results of this study suggest thatsmall mammals may be more capable of interpatch movement without corridors thanis frequently assumed.This revised version was published online in May 2005 with corrections to the Cover Date.     

Quercetin regulates Fas expression and induces apoptosis in hepatocellular carcinoma HepG2 cells

AIM: To investigate the role of 1, 4, 5- trisphosphate inositol (IP3) and Fas gene expression in apoptosis of HepG2 cells induced by quercetin. METHODS: HepG2 cells were treated with quercetin at different concentrations (including 20, 40, 60, 80 μmol/ L) for 72 h and treated with 60 μmol/ L quercetin for 6 h, 12 h, 24 h, 48 h and 72 h. IP3, Fas mRNA, Fas protein and apoptosis rate were assayed by IP3 - ［3H］ Birtrak assay, RT-PCR, Western blotting and flow cytometry, respectively. RESULTS: When HepG2 cells were incubated with different concentrations of quercetin for 72 h, the IP3 content was lower than those in control. Fas mRNA expression, Fas protein expression and the apoptosis rate were higher than those in control. When HepG2 cells were incubated with quercetin for 6 h, 12 h, 24 h, 48 h, 72 h, the IP3 contents were lower than those in control incubated with 60 μmol/L quercetin for 12 h. Fas mRNA expression was higher than that in control incubated with 60 μmol/L quercetin for 12 h . Fas protein expression was higher than that in control. The apoptosis rate was significantly higher than that in control incubated with 60 μmol/L quercetin for 24 h (P<0.01). CONCLUSION: Quercetin induces apoptosis of HepG2 cells by reducing IP3 production and upregulating Fas gene expression.