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991.
小麦新品种烟农5158及其亲本旗叶生理特性研究   总被引:1,自引:0,他引:1  
在盆栽条件下,以小麦新品种烟农5158及其亲本鲁麦14号、烟农15号和烟航选2号为材料,研究烟农5158旗叶生理特性与亲本之间的差异.结果表明,烟农5158及其亲本旗叶净光合速率均在开花期达到最大,之后逐渐下降,在生育后期差异显著,烟农5158旗叶净光合速率始终高于其亲本.与亲本相比,烟农5158旗叶中抗氧化酶SOD、POD和CAT活性在生育后期下降缓慢且维持较高水平;烟农5158及其亲本旗叶中的SOD、POD和APX活性均随生育进程推进呈先升高后降低的趋势;花后7~28 d,烟农5158旗叶中POD活性显著高于其亲本.烟农5158与其亲本相比具有较高的可溶性蛋白含量,生育后期具有较低的MDA含量.烟农5158在生育后期具有叶片衰老缓慢、净光合速率高、抗逆性强的特点,这可能与它开花后旗叶中抗氧化酶活性较高、可溶性蛋白含量较高和MDA含量较低有关.  相似文献   
992.
Garry Kerch 《Marine drugs》2015,13(4):2158-2182
Age-related, diet-related and protein conformational diseases, such as atherosclerosis, diabetes mellitus, cancer, hypercholesterolemia, cardiovascular and neurodegenerative diseases are common in the elderly population. The potential of chitosan, chitooligosaccharides and their derivatives in prevention and treatment of age-related dysfunctions is reviewed and discussed in this paper. The influence of oxidative stress, low density lipoprotein oxidation, increase of tissue stiffness, protein conformational changes, aging-associated chronic inflammation and their pathobiological significance have been considered. The chitosan-based functional food also has been reviewed.  相似文献   
993.
To investigate the effect of low light (LL, 50% natural light) during grain filling (GF) stage on rice transamination, amino acid (AA) accumulation, nutritional value, and cooking quality in three different rice genotypes, transaminase activities and AA levels in grains during GF stage and the traits that significantly affected rice quality (physical appearance, cooking quality, and nutritional value) were analyzed. LL did not disturb transamination in rice grains during GF stage, as minimal impact was found on alanine and aspartate transaminase activities. Nevertheless, most AAs in caryopses, including lysine and threonine, increased in response to LL, except for sulfur-containing AAs. These results suggest that AA metabolism and accumulation in rice grains were rarely suppressed by LL during GF stage. Rice nutritional ingredients at harvest, such as major protein components including glutelin and most important essential amino acids (EAAs) including lysine and threonine, increased significantly in response to LL, whereas most protein and EAA ratios were rarely affected. However, LL markedly affected physical appearance of rice grains by reducing brown rice rate, milled rice rate, and 1000-grain weight and increasing the chalkiness rate. In addition, cooking qualities decreased in response to LL, while breakdown values and amylose levels decreased and setback values increased. We concluded that LL during GF stage decreased the cooking quality of rice, but could potentially improve the nutritional value of rice.  相似文献   
994.
Background: the ketogenic diet (KD) has become a widely used nutritional approach for weight loss. Some of the KD’s positive effects on metabolism and cardiovascular risk factors are similar to those seen after n-3 polyunsaturated fatty acids (ω-3) supplementation. We hypothesized that a ketogenic Mediterranean diet with phytoextracts combined with ω-3 supplementation may have increased positive effects on cardiovascular risk factors and inflammation. Methods: We analyzed 34 male overweight subjects; aged between 25 and 65 years who were overall healthy apart from overweight. The subjects followed a ketogenic diet protocol for four weeks; with (KDO3) or without (KD) ω-3 supplementation. Results: All subjects experienced a significant loss of body weight and body fat and there was no significant differences between treatment (body weight: KD—4.7 kg, KDO3—4.03 kg, body fat KD—5.41 kg, KDO3—5.86 kg). There were also significant decreases in total cholesterol, LDL-c, and glucose levels. Triglycerides and insulin levels decreased more in KDO3 vs. KD subjects, with a significant difference. All the investigated inflammatory cytokines (IL-1β, IL-6, TNF-α) decreased significantly in KDO3 subjects whilst only TNF-α showed a significant decrease in KD subjects over the 12 month study period. No significant changes were observed in anti-inflammatory cytokines (IL-10 and IL-1Ra), creatinine, urea and uric acid. Adiponectin increased significantly only in the KDO3 group. Conclusions: ω-3 supplementation improved the positive effects of a ketogenic Mediterranean diet with phytoextracts on some cardiovascular/metabolic risk factors and inflammatory state.  相似文献   
995.
Biopolymers are very favorable materials produced by living organisms, with interesting properties such as biodegradability, renewability, and biocompatibility. Biopolymers have been recently considered to compete with fossil-based polymeric materials, which rase several environmental concerns. Biobased plastics are receiving growing interest for many applications including electronics, medical devices, food packaging, and energy. Biopolymers can be produced from biological sources such as plants, animals, agricultural wastes, and microbes. Studies suggest that microalgae and cyanobacteria are two of the promising sources of polyhydroxyalkanoates (PHAs), cellulose, carbohydrates (particularly starch), and proteins, as the major components of microalgae (and of certain cyanobacteria) for producing bioplastics. This review aims to summarize the potential of microalgal PHAs, polysaccharides, and proteins for bioplastic production. The findings of this review give insight into current knowledge and future direction in microalgal-based bioplastic production considering a circular economy approach. The current review is divided into three main topics, namely (i) the analysis of the main types and properties of bioplastic monomers, blends, and composites; (ii) the cultivation process to optimize the microalgae growth and accumulation of important biobased compounds to produce bioplastics; and (iii) a critical analysis of the future perspectives on the field.  相似文献   
996.
【目的】探讨饲料中不同脂肪源对洛氏鱥(Rhynchocypris lagowskii Dybowski)生长及消化酶和蛋白质代谢酶活性的影响。【方法】以初始体质量为(15.68±0.30) g/尾的洛氏鱥幼鱼为研究对象,在基础饲料中分别添加4.42%的玉米油、豆油、鱼油、棕榈油、猪油、混合油(质量比为:鱼油∶豆油∶猪油=3∶4∶3),配制成6种等氮等脂的试验饲料,进行为期8周的饲养试验。饲养试验结束后,测定洛氏鱥生长性能指标,肌肉中主要营养成分,蛋白酶、脂肪酶、淀粉酶、谷草转氨酶以及谷丙转氨酶的活力。【结果】混合油组洛氏鱥的终末体质量显著高于豆油、棕榈油及猪油组(P0.05),但与玉米油组和鱼油组差异不显著(P0.05);混合油组洛氏鱥的饲料效率、蛋白质效率及蛋白质沉积率显著高于棕榈油及猪油组(P0.05),但与玉米油、豆油及鱼油组差异不显著(P0.05)。混合油组和鱼油组洛氏鱥肌肉中的粗蛋白质含量显著高于玉米油、豆油、棕榈油及猪油组(P0.05);猪油组洛氏鱥肌肉中的粗脂肪含量显著高于鱼油组(P0.05)。混合油组洛氏鱥肝胰脏、前肠及中肠的蛋白酶活性与鱼油组差异不显著(P0.05),但二者均显著高于猪油组(P0.05);混合油组洛氏鱥后肠蛋白酶活性显著高于豆油、玉米油、猪油以及棕榈油组(P0.05)。混合油组洛氏鱥肝胰脏的脂肪酶活力显著高于棕榈油组(P0.05);混合油、鱼油和玉米油组洛氏鱥中肠的脂肪酶活力差异不显著(P0.05),但均显著高于豆油、猪油及棕榈油组(P0.05)。不同脂肪源饲料对洛氏鱥肝胰脏、前肠、中肠及后肠的淀粉酶活力无显著影响(P0.05)。混合油组和鱼油组洛氏鱥肝胰脏谷草转氨酶和谷丙转氨酶活力显著高于猪油组和棕榈油组(P0.05)。【结论】从洛氏鱥生长性能及消化代谢角度来看,混合油组和鱼油组饲料的效果最好,玉米油、豆油和棕榈油组次之,猪油组最差。  相似文献   
997.
目的 观察加减苍附导痰汤对痰湿阻滞型非酒精性脂肪性肝病(non-alcoholicfattyliverdisease,NAFLD)氧化应激水平及脂质代谢的影响。方法 将82例痰湿阻滞型NAFLD患者随机分为治疗组42例和对照组40例。治疗组给予口服加减苍附导痰汤,对照组给予口服奥利司他胶囊,两组的疗程均为12周。观察两组患者治疗前后总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、血清丙氨酸氨基转移酶(ALT)、血清天冬氨酸氨基转移酶(AST)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平、肝脏脂肪含量(LFC)及不良反应的发生情况。结果 治疗后两组患者TC、TG、LDL-C、HDL-C均较治疗前显著改善(P<0.05),且治疗组各项指标的改善优于对照组(P<0.05);两组血清ALT、AST、MDA及LFC较治疗前明显降低,而血清SOD水平升高(P<0.05),且治疗组各项指标的改善优于对照组(P<0.05)。结论 加减苍附导痰汤对痰湿阻滞型NAFLD患者保肝降酶及降低肝脏脂肪含量有较好的疗效,可能与其提高抗氧化及脂质代谢水平有关。  相似文献   
998.
以2株新近分离出来的链带藻(Desmodesmus sp. QL96和Desmodesmus sp. QJ74)为研究对象,检测胞内主要细胞代谢产物组成及含量变化,找出优势细胞代谢产物。收集相同时间间隔下培养的2株微藻,经过冻干、研磨、复溶,制备成细胞溶解液,再进行逐级萃取,分级检测每个萃取步骤中所得细胞代谢产物的含量。结果表明:在BG11培养基中生长30 d,链带藻Desmodesmus sp. QL96和Desmodesmus sp. QJ74的最高蛋白含量分别达到细胞干重的71.68%和62.14%,其他代谢产物,如碳水化合物、脂质和色素,在2株微藻中的含量都没有超过20%。对比其他微藻的文献报道,链带藻Desmodesmus sp. QL96是目前发现的蛋白含量最高的藻株,其蛋白的表达模式和蛋白相关产品的开发具有研究价值。  相似文献   
999.
It has been reported that cyanidin 3-O-glucoside (C3G) is an inhibitor of Helicobacter pylori toxin secretion. C3G is classified as an anthocyanin and is a major component of black rice extract (BRE). The present study aimed to identify a new functional food material to prevent H. pylori infection in Mongolian gerbil model. Toxicity in the liver and kidney were not detected after BRE administration (10 or 50 mg/kg). BRE treatment reduced bacterial colonization in animal gastric tissue, as well as infection signs as observed on the analysis of the hematological data. It was also found that the relative mRNA levels of the inflammatory cytokines were reduced in BRE-treated groups. These findings suggest that BRE acts as a potent inhibitor of H. pylori infection and pathogenesis in Mongolian gerbils. We propose that BRE may be used to manage gastroduodenal diseases caused by H. pylori infection.  相似文献   
1000.
珍珠豆型花生脂肪酸变化规律研究   总被引:1,自引:0,他引:1  
露地栽培条件下,以海南小粒粉皮、海南小粒红皮和桂花36为试验材料,通过检测果针不同入土时间(10d、20d、30d、40d、50d、60d)籽仁脂肪酸含量,分析珍珠豆型花生籽仁发育过程中脂肪酸含量的变化规律。结果表明,在花生籽仁发育过程中,脂肪酸变化主要取决于油酸和亚油酸的变化,油酸、O/L值和不饱和脂肪酸/饱和脂肪酸值均随籽仁成熟度的增加而增加;果针入土60d时,桂花36的油酸含量、O/L值和不饱和脂肪酸/饱和脂肪酸值均同比最大,分别为51.14%、1.85、3.93;亚油酸含量最大值出现在果针入土30d的海南小粒红皮为36.04%,亚油酸最小值出现在果针入土60d时的桂花36为27.64%;其他六种脂肪酸中除了硬脂酸含量有所上升之外,棕榈酸、亚麻酸、花生酸、花生稀酸、山嵛酸基本为下降趋势。  相似文献   
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