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71.
芥菜型油菜黄黑种皮多酚差异的紫外-可见光谱研究   总被引:4,自引:0,他引:4  
曾盔  刘忠松  龙桑  严明理 《作物学报》2007,33(3):476-481
以芥菜型自交系黄黑油菜种皮为材料,研究了其多酚提取液的紫外-可见吸收光谱, 测定了芥菜型油菜黄黑种皮样以没食子酸和茶儿茶素标准计的多酚含量,发现黄种皮的多酚含量约为黑种皮的90%,显著区别于甘蓝型油菜的10%,因此多酚含量高可能是芥菜型黄籽油菜性状稳定的根本内因。基于香草醛试验,推测黑种皮中含有3-OH的黄烷醇类多酚,而黄种皮中没有。基于加入位移试剂后特征吸收谱带Ⅰ与Ⅱ的位移方向与大小,推测黄酮醇类多酚A环在黄种皮中可能主要为单酚羟基,而在黑种皮中可能主要为邻二酚羟基结构。这种多酚分子的结构差异可能是形成芥菜型油菜黄黑种皮色泽差异的主要原因。  相似文献   
72.
Sargassum horneri (S. horneri), an edible brown alga, has been proposed as a functional food with an improvement effect on abnormal skin immune responses. The present study investigates the anti-allergic effect of an ethanol extract from S. horneri (SHE) on immunoglobulin E (IgE)/bovine serum albumin (BSA)-mediated activation in bone marrow-derived cultured-mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) reaction in mice. SHE markedly and dose-dependently suppressed the degranulation of BMCMCs by reducing the β-hexosaminidase and histamine release without cytotoxicity. In addition, SHE significantly decreased the FcεRI expression on the surface of BMCMCs and its IgE binding. Moreover, SHE reduced the mRNA expression and the production of allergic cytokines; interleukin (IL)-1β, IL-4, IL-5, IL-6, IL-10, IL-13; interferon (IFN)-γ and/or tumor necrosis factor (TNF)-α; and a chemokine, thymus and activation-regulated chemokine (TARC), by suppressing the activation of Src-family kinases and nuclear factor (NF)-κB signaling. In further study, the application of SHE reduced the PCA reaction in an IgE/BSA-induced type I allergic mice model. Taken together, we suggest that SHE has an anti-allergic effect in type I allergic responses.  相似文献   
73.
基于EST-SSR和SNP标记的大麦麦芽纯度检测   总被引:3,自引:0,他引:3  
大麦麦芽作为啤酒酿造的主要原料之一,其纯度决定了麦芽原料的均一性,进而影响加工工艺和啤酒品质。为高效准确地鉴定麦芽纯度,在啤酒企业进行麦芽原料采购和质量监测时提供参考依据。本研究分别利用EST-SSR和SNP标记定性检测了按比例预混的麦芽样品纯度,并利用SNP标记定量检测了4份送检的麦芽盲样纯度。结果表明,EST-SSR标记能定性检测混杂度高于10%的麦芽样品,而SNP标记能够有效鉴定混杂度低至5%的麦芽样品。SNP标记对纯度定量检测的单次抽样的测定值与真实值之间的误差在3%以内。比较发现,本研究所用的两类分子标记均可用于麦芽样品的纯度检测,但基于KASP技术的SNP标记可以满足麦芽纯度的快速定量检测需要。  相似文献   
74.
This study was conducted to evaluate the growth characteristics and fatty acid composition among 15 kenaf mutants derived from the kenaf germplasm C14 and 15 kenaf accessions originating from Russia, India, China, Iran, and Italy. The overall growth performance (plant height, stem diameter, flowering date, leaf, and flower size) of the stem color mutant lines derived from C14 are similar to those of the original variety. However, the flower color mutant lines derived from C14 showed flowering to occur 10 days later when compared with the original variety and showed smaller leaf sizes than the original variety. Late-ripened kenaf accessions (Jinju, Auxu, and Jnagdae) can yield more bio-mass compared with early or medium-maturing germplasm. The late maturity kenaf (Auxu, Jinju, and Jangdae) has a higher oil percentage than the early maturity germplasm. Linoleic, oleic, and palmitic acids were the predominant fatty acids in all kenaf seeds. The stem color mutant lines significantly surpassed the parental means of all saturated fatty acids. In addition, the flower color mutant lines showed broad ranges of variation in oleic acid. The 15 accessions showed a wide range of fatty acid compositions, spanning from 29.75 to 38.30% saturated fatty acids and 61.70 to 70.24% total unsaturated fatty acids, and the late maturity kenaf has a higher linoleic acid percentage than the early maturity germplasm. The flowering period was highly positively (P ≤ 0.01) correlated with the plant height, stem diameter, oil percent, and linolenic acid (C18:3), and it was significantly negatively (P ≤ 0.01) correlated with stearic acid (C18:0). These results will provide valuable information to assist the parental selection of kenaf breeding.  相似文献   
75.
Six new β-resorcylic acid derivatives (1–5 and 7) were isolated from a halophyte-associated fungus, Colletotrichum gloeosporioides JS0419, together with four previously reported β-resorcylic acid lactones (RALs). The relative and absolute stereochemistry of 1 was completely established by a combination of spectroscopic data and chemical reactions. The structures of the isolated compounds were elucidated by analysis of HRMS and NMR data. Notably, compounds 1–3 had a β-resorcylic acid harboring a long unesterified aliphatic side chain, whereas the long aliphatic chains were esterified to form macrolactones in 4–9. Among the isolated compounds, monocillin I and radicicol showed potent antifungal activities against Cryptococcus neoformans, comparable to clinically available antifungal agents and radicicol showed weak antifungal activity against Candida albicans. These findings provide insight into the chemical diversity of fungal RAL-type compounds and their pharmacological potential.  相似文献   
76.
Meropenem, a second carbapenem antimicrobial agent with a broad spectrum of activity, is used to treat sepsis and resistant‐bacterial infections in veterinary medicine. The objective of this study was to identify the pharmacokinetics of meropenem in dogs receiving intermittent hemodialysis (IHD) and to determine the proper dosing in renal failure patients receiving IHD. Five healthy beagle dogs were given a single i.v. dose of 24 mg/kg of meropenem and received IHD. The blood flow rate, dialysate flow, and ultrafiltration rate were maintained at 40 mL/min, 300 mL/min, and 40 mL/h, respectively. Blood samples were collected for 24 h from the jugular vein and from the extracorporeal arterial and venous line. Urine samples and dialysate were also collected. The concentrations of meropenem were assayed using HPLC/MS/MS determination. The peak plasma concentration was 116 ± 37 μg/mL at 15 min. The systemic clearance was 347 ± 117 mL/h/kg, and the steady‐state volume of distribution was 223 ± 67 mL/kg. Dialysis clearance was 71.1 ± 34.3 mL/h/kg, and the extraction ratio by hemodialysis was 0.455 ± 0.150. The half‐life (T1/2) in dogs with IHD decreased compared with those without IHD, and the reduction in T1/2 was greater in renal failure patients than in normal patients. Sixty‐nine percent and 21% of the administered drug were recovered by urine and dialysate in the unchanged form, respectively. In conclusion, additional dosing of 24 mg/kg of meropenem after dialysis could be necessary according to the residual renal function of the patient based on the simulated data.  相似文献   
77.
The 23 open reading frame (ORF) 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus (PRRSV) were collected from viremic sera from the (modified live vaccine) MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences, including type I Korean PRRSV, and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs, one subgroup had 87.2~88.9% similarity with the Lelystad virus, showing a close relationship with the 27~2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages, subgroups 1, 2, 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 (48%). The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion, the existence of type I PRRSV, which was genetically different from Lelystad virus (Prototype of type I PRRSV), and heterologous type II PRRSVs of viremic pigs detected even in the MLV-vaccinating farms indicated the need for new vaccine approaches for the control of PRRSV in Korea.  相似文献   
78.
为探究不同添加剂对青稞秸秆与多年生黑麦草(4∶6)混合青贮发酵品质的影响,试验设对照组(C)、乳酸菌制剂组(LAB)、糖蜜组(M)、乳酸菌制剂+糖蜜组(LAB+M)4个处理,青贮后第7, 24和45天打开,测定青贮发酵品质。结果表明,添加乳酸菌制剂加速了青贮早期乳酸发酵进程,但由于底物不足,青贮后期丁酸含量和氨态氮/总氮值有所升高;添加糖蜜补充了发酵底物,促进了乳酸发酵,显著(P<0.05)提高了乳酸含量,降低了pH值(P<0.05),从而有效地抑制了有害微生物的活性,减少了丙酸和丁酸的生成。乳酸菌制剂+糖蜜组与单独添加乳酸菌制剂组相比显著提高了青贮发酵品质, 但与单独添加糖蜜组相比差异不显著,表明发酵底物不足是限制青稞秸秆与多年生黑麦草混合青贮发酵品质的主要因素。  相似文献   
79.
The antioxidant activities of six Korean rice wine (KRW) concentrates were measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and lipid/malonaldehyde (MA) assays. In the DPPH assay, the antioxidant activities of the KRW concentrates, including Maesilju (MSJ), Kookhwaju-1 (KHJ-1), Kookhwaju-2 (KHJ-2), Gugijaju (GGJ), Sasamju (SSJ), and Sogokju (SGJ), were 40%, 66%, 64%, 35%, 35%, and 63%, respectively. Furthermore, the concentrates inhibited the formation of MA from cod liver oil by 49%, 83%, 75%, 82%, 89%, and 90%, respectively, according to the lipid/MA assay. The sample wines were also analyzed for pH, titratable acidity, soluble solids (°Bx), and reducing sugars. The antioxidant activities of volatile extracts of the KRWs extracted by a solvent assisted flavor evaporation (SAFE) apparatus were evaluated by aldehyde/carboxylic acid assay. The volatile extracts of MSJ, KHJ-1, KHJ-2, GGJ, SSJ, and SGJ inhibited the oxidation of hexanal by 97%, 99%, 90%, 90%, 50%, and 51%, respectively. Among the nonvolatile extracts of KRWs, KHJ-2 showed the highest inhibitory effect on MA formation.  相似文献   
80.
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