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11.
用γ射线处理三个大蒜品种的鳞茎,VM_1代出苗率及植株存活率降低,生长发育受阻,抽苔率降低,鳞茎变小,并出现形态学畸变,VM_1代主要表现为辐射损伤,不宜进行突变性状选择;VM_2代仍有较严重的辐射损伤,开始出现纯合突变,性状变异范围扩大、变异度增大,抽苔期及质量性状选择可在VM_2进行,但不宜进行株高突变及高产变异类型的选择;VM_3代开始出现鳞茎数量性状有益突变,可以进行高产突变类型选择。  相似文献   
12.
This study was conducted to determine the potential interaction of aged garlic extract (AGE) with carvedilol (CAR), as well as to investigate the role of S-allyl-l-cysteine (SAC), an active constituent of AGE, in rats with isoproterenol (ISO)-induced myocardial dysfunction. At the end of three weeks of treatment with AGE (2 and 5 mL/kg) or SAC (13.1 and 32.76 mg/kg), either alone or along with CAR (10 mg/kg) in the respective groups of animals, ISO was administered subcutaneously to induce myocardial damage. Myocardial infarction (MI) diagnostic predictor enzymes, lactate dehydrogenase (LDH) and creatinine kinase (CK-MB), were measured in both serum and heart tissue homogenates (HTH). Superoxide dismutase (SOD), catalase, and thiobarbituric acid reactive species (TBARS) were estimated in HTH. When compared with other groups, the combined therapy of high doses of AGE and SAC given alone or together with CAR caused a significant decrease in serum LDH and CK-MB activities. Further, significant rise in the LDH and CK-MB activities in HTH was noticed in the combined groups of AGE and SAC with CAR. It was also observed that both doses of AGE and SAC significantly increased endogenous antioxidants in HTH. Furthermore, histopathological observations corroborated the biochemical findings. The cytoprotective potential of SAC and AGE were dose-dependent, and SAC was more potent than AGE. The protection offered by aged garlic may be attributed to SAC. Overall, the results indicated that a high dose of AGE and its constituent SAC, when combined with carvedilol, has a synergistic effect in preventing morphological and physiological changes in the myocardium during ISO-induced myocardial damage.  相似文献   
13.
用不同浓度的亚硒酸钠溶液分别处理大蒜根尖6小时,18小时和24小时,发现硒对大蒜根尖细胞的毒害作用与其浓度和作用时间有关:当处理时间≤18小时、硒的浓度≤1μg/ml时,促进大蒜根尖细胞的有丝分裂;反之则抑制,说明硒具有二重性.同时还观察到染色体畸变现象.  相似文献   
14.
本法利用单缝石英管,提高火焰原子吸收法的灵敏度并降低测试成本。方法用于大米、蒜头、茶叶中硒的测定,获得满意的结果。  相似文献   
15.
We describe a short total synthesis of ajoene, a major biologically active constituent of garlic. The instability of allicin as the only other known alternative starting material has led to the development of a reliable procedure for the synthesis of ajoene from simple building blocks that is also suitable for upscale operations.  相似文献   
16.
冯金城  王洪隆 《色谱》1995,13(6):479-480
In the paper,the study on the change in callus of garlic by thin-layer chromatography is decribed.The results showed that a decreasing tendency is presented for isoperoxidase but a increasing one for the total activity inthe preduction of callus from garlic sprout.  相似文献   
17.
The aim of this study was to evaluate the chemical compounds of garlic essential oil (EO), and determine the antifungal efficacy of garlic EO and its major components, diallyl trisulfide and its nanoemulsions against wood-rotting fungi, Trametes hirsuta and Laetiporus sulphureus. GC-MS analysis revealed that the major constituents of garlic EO were diallyl trisulfide (39.79%), diallyl disulfide (32.91%), and diallyl sulfide (7.02%). In antifungal activity, the IC50 value of garlic EO against T. hirsuta and L. sulphureus were 137.3 and 44.6 μg/mL, respectively. Results from the antifungal tests demonstrated that the three major constituents were shown to have good antifungal activity, in which, diallyl trisulfide was the most effective against T. hirsuta and L. sulphureus, with the IC50 values of 56.1 and 31.6 μg/mL, respectively. The diallyl trisulfide nanoemulsions showed high antifungal efficacy against the examined wood-rotting fungi, and as the amount of diallyl trisulfide in the lipid phase increases, the antifungal efficacy of the nanoemulsions increases. These results showed that the nanoemulsions and normal emulsion of diallyl trisulfide have potential to develop into a natural wood preservative.  相似文献   
18.
研究了超滤对大蒜粗多糖中蛋白质的脱除效果.选择截留相对分子质量为10000的超滤膜(MWCO),并研究了超滤次数、操作压力、样品浓度和膜的清洗方式对超滤效果的影响.结果表明:利用该超滤膜来脱除大蒜粗多糖中蛋白质的最佳条件为:大蒜多糖的质量浓度20mg/mL,压力27.58kPa,超滤3次.该条件下大蒜多糖通过率达到92.1%,蛋白质含量由O.5%降低到了0.05%.超滤膜使用后,不经清洗,再次使用,大蒜多糖的通过率为74.7%,为原通过率的78.1%;经蒸馏水一Na0H溶液一蒸馏水混合清洗后,大蒜多糖的通过率为93.2%,恢复到原通过率的97.5%.结论:采用超滤法可以脱除大蒜粗多糖中的蛋白质.  相似文献   
19.
为了在提取和保存过程中提高大蒜制品中蒜素的含量,进行了蒜素后续反应的稳定性和蒜氨酸酶对蒜素后续反应影响的研究.以蒜素为检测指标,乙醇提取新鲜去皮大蒜中的蒜素,分光光度法测量蒜素含量.研究了不同温度、真空度和光照等因素下对蒜素后续降解反应的影响,提取蒜氨酸酶,研究了蒜氨酸酶对蒜素后续降解反应的影响.研究表明:低温、真空及遮光条件下进行蒜素的提取或保存,蒜素比较稳定,降解缓慢;蒜氨酸酶会催化蒜素的降解反应,随着加酶量的增加,降解反应速度增加.  相似文献   
20.
目的:研究大蒜多糖B(GP-B)对免疫抑制小鼠体内免疫活性的调节作用.方法:用氢化可的松(HC)皮下注射制造免疫功能抑制的动物模型,以左旋咪唑作为阳性药物对照.给模型小鼠分别灌胃生理盐水、多糖溶液,连续12 d,灌胃多糖溶液质量分数分别为1 600、800和400 mg/kg.通过流式细胞仪检测外周血T淋巴细胞亚群CD_3~+、CD_4~+、CD_8~+的百分比,计算胸腺指数和脾脏指数,检测脾细胞增殖情况及腹腔巨噬细胞吞噬功能等实验对大蒜多糖B的免疫学活性进行研究.结果:以大蒜多糖B质量分数为800 ms/kg灌胃的小鼠CD_3~+CD_4~+T细胞百分率以及CD_4~+/CD_8~+比值明显增高(P<0.05),同时免疫抑制小鼠腹腔巨噬细胞的吞噬活性显著增强(P<0.05).但该浓度的GP-B降低了CD_3~+CD_8~+细胞百分比(P<0.05),且对脾T淋巴细胞转化率无促进作用.结论:大蒜多糖B对免疫抑制小鼠的T淋巴细胞亚群及巨噬细胞的吞噬功能具有正向调节作用.  相似文献   
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