首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 61 毫秒
1.
以干青蒿叶粉末为原料,以青蒿素提取量为考察指标,采用有机溶剂提取法,以料液比、温度、时间为考察因素,在单因素试验基础上进行了3因素3水平正交实验,研究提取青蒿素的最佳工艺条件。结果表明:青蒿素的最佳提取条件为料液比1∶20g/mL,提取温度50℃,提取时间2.5h,青蒿素提取量达5.27mg/g。  相似文献   

2.
紫叶李资源丰富,树叶中含有较多的活性成分如多酚物质,但目前相关的研究报道很少。试验选取有机溶剂提取法提取紫叶李中的多酚物质,以多酚物质含量为考察指标,采用单因素试验考察提取温度、乙醇浓度、提取时间和料液比等因素的影响,在单因素试验的基础上进行正交试验,优化紫叶李树叶中多酚物质的提取工艺条件。结果发现,对多酚含量影响最大的因素为提取时间,影响最小的为提取温度;有机溶剂提取紫叶李树叶中多酚物质的最佳工艺条件为提取温度60℃、乙醇浓度60%、提取时间75 min、料液比1:20,此条件下提取的紫叶李树叶中多酚含量为8.12 mg/g。  相似文献   

3.
以香粉1号香蕉果肉为试材,通过单因素试验和L9(34)正交试验,筛选用有机溶剂提取香粉1号果肉类胡萝卜素的最佳提取条件,并测定其含量。结果表明:以乙醇为提取剂效果最好;影响提取效果大小的因素依次为料液比、乙醇浓度、提取温度、提取时间;最佳提取条件为:乙醇浓度95%、料液比1∶15、提取温度50℃、提取时间1.5 h,在最佳提取条件下,测得香粉1号香蕉果肉类胡萝卜素平均含量为14.073μg/g。  相似文献   

4.
水提法同步提取分离香菇中蛋白质和多糖的工艺研究   总被引:1,自引:0,他引:1  
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%。  相似文献   

5.
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。  相似文献   

6.
茶薪菇子实体多糖的提取条件进行优化研究,采用单因素与复因素试验方法确定了最佳的提取温度、提取时间、pH值和料液比。结果表明:提取温度、时间、pH值和液料比对茶薪菇多糖提取量影响显著,在提取条件为温度90℃、提取时间2h、料液比1∶20、pH8.0,茶薪菇多糖提取量最高为28.04mg/g,显著高于其他条件。  相似文献   

7.
采用有机溶剂法提取马尾松中的总黄酮,研究了溶剂种类、提取时间、料液比单因素及对应因素的正交试验对马尾松松针总黄酮提取的影响。结果表明:单因素试验中,最优提取条件为70%乙醇溶剂、提取时间1.5h、料液比1:40;正交试验中,所研究的因素对此马尾松松针总黄酮的提取影响不大。  相似文献   

8.
响应面法优化超声提取锁阳多糖工艺研究   总被引:1,自引:0,他引:1  
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。  相似文献   

9.
水蜡树果中原花青素的最佳提取工艺研究   总被引:1,自引:0,他引:1  
在单因素实验的基础上,采用正交L9(34)设计,研究提取温度、提取时间、提取剂、料液比对水蜡树果原花青素提取率的影响。结果表明:温度60℃,料液比1∶10,时间40 min,乙醇浓度60%提取时,原花青素的含量最高,可达2.413%;对原花青素提取率的影响作用大小顺序为提取剂提取时间提取温度料液比。  相似文献   

10.
研究了提取温度、提取时间、料液比、pH和提取次数对金针菇水溶性粗多糖提取率的影响。单因素试验结果表明,pH和提取次数的影响作用较弱,二因素的适宜水平分别为7和1次;而提取温度、提取时间和料液比的影响较显著。采用Box—Behnken组合设计进一步考察3个因子对金针菇粗多糖提取率的影响。试验结果表明,对金针菇粗多糖提取率影响大小依次为:料液比〉提取时间〉提取温度;所确定的最优提取条件为:提取温度87℃,提取时间2h,料液比1:20,在此条件下金针菇粗多糖提取率为1.38%。  相似文献   

11.
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   

12.
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   

13.
Zusammenfassung Die Leistungsprüfungen wurden im Zeitraum 1997 bis 2003 mit den Unterlagen Gisela 4 und 5, den Klonnummern 195/20 und 497/8 aus der Gisela-Serie sowie Weiroot 10, 13, 53, 72 und 158 durchgeführt. Dabei dienten Sämlinge von P1 (bulgarische Selektion aus Prunus mahaleb) als Kontrolle. Alle Unterlagen waren mit der Sorte Stella veredelt und im Dezember 1996 in der Versuchsanlage der Agraruniversität in Plovdiv, Bulgarien, im Abstand von 6 m×4,5 m gepflanzt worden. Dabei erfolgte ein Pflanzschnitt. Nach Abschluss der natürlichen Kronenentwicklung wurde jedes Jahr ein Winterschnitt vorgenommen. Der Boden wurde durch mechanische Bearbeitung offen gehalten und nach dem 4. Standjahr wurden die Baumstreifen mit Herbiziden behandelt. Die Wasserversorgung erfolgte durch eine dem natürlichen Gefälle folgende Überflutung, allerdings nicht immer zum optimalen Zeitpunkt, da keine eigene Wasserquelle zur Verfügung stand.Basierend auf den Ergebnissen bis zum Anfang des 7. Standjahres können die untersuchten Unterlagen in zwei Gruppen differenziert werden: starkwüchsig—Weiroot 10, P1 und Weiroot 13; mittelstarkwachsend bis schwachwüchsig—Gi 497/8, Gisela 4, Weiroot 53, Weiroot 158, Gi 195/20, Weiroot 72 und Gisela 5. Letztere zeichnete sich durch besondere Schwachwüchsigkeit aus. Die meisten Wurzelschosser bildeten Gisela 4, Weiroot 10 und Weiroot 13. Weiroot 53, Weiroot 72 und Weiroot 158 entwickelten deutlich weniger und P1, Gisela 5, Gi 195/20 sowie Gi 497/8 keine Wurzelschosser. Den frühesten Blühbeginn induzierte Gisela 4. Die anderen Unterlagen führten, in Abhängigkeit von den Temperaturbedingungen des jeweiligen Jahres, zu einer Verspätung der Blüte: P1 und Weiroot 10 um 1–2 Tage; Gi 497/8, Weiroot 13 und Weiroot 158 um 2–4 Tage; Weiroot 72 um 2–7 Tage; Gi 195/20 um 3–6 Tage; Weiroot 53 um 3–8 Tage und Gisela 5 um 3–10 Tage. Die Reifezeit der Früchte war bei den Bäumen auf Gisela 5 im Vergleich zu den anderen Varianten um 2–3 Tage verspätet. Gisela 5, Weiroot 72 und Gisela 4 induzierten bei der aufveredelten Sorte die höchsten Ertragsleistungen, P1 die geringsten. Bei den Bäumen auf Gisela 5 war die Fruchtgröße geringer als bei den anderen Unterlagen. Bäume auf Gisela 5 brauchen intensive Pflege. Nur wenn alle Produktionsfaktoren und kulturtechnischen Maßnahmen optimiert werden, kann das hohe Ertragspotenzial dieser Unterlage ausgeschöpft werden.  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号