反刍动物肽营养研究进展

本文综述了反刍动物肽的吸收特点及影响因素,肽的吸收代谢机制,肽对瘤胃微生物的调控及对反刍动物生产性能发挥的作用,以及饲料蛋白源活性肽的开发应用。     

Biochemical proximates of pumpkin (Cucurbitaeae spp.) and their beneficial effects on the general well‐being of poultry species

There is a growing need to increase productivity in poultry. Growth hormones and antibiotics have the ability to improve health, weight gain and feed efficiency in meat‐producing animals. The growth‐promoting antibiotics are administered to poultry to improve the general performance of the chicken. However, the use of the xenobiotic drugs in food‐producing animals has been a concern and a sensitive issue of debate for several decades in the EU and many other regional blocks of the world. Consequently, the use of hormones in animal production has been banned in Italy, Denmark and Germany for over 4–5 decades, while Belgium and Greece had never permitted its use for livestock fattening purposes. Bioactive phytochemicals exhibit antimicrobial, antioxidant, antiparasitic, antiprotozoal, antifungal and anti‐inflammatory properties and consequently have several beneficial effects on appetite, growth and the immune status of the animal. In South Africa, different species of pumpkin are produced for food due to their high nutrient content. The flesh serves as a traditional food, while the seeds and peels are commonly discarded. Pumpkin seed extract is reported to be useful for immunomodulation, reproductive health, therapeutics over a wide range of disease conditions and stimulates metabolism of accumulated fats. Studies have also shown that pumpkin seeds are a valuable source of protein and fat. Their complexity and extent of bioactivity offers sustainable prospects for natural control of pathogenic/parasitic organisms, stimulate nutrition or enhance resistance to disease infections, and reduce abdominal fat and serum levels of harmful lipids, while increasing serum levels of beneficial lipids.     

Pharmacokinetic profiles of the two major active metabolites of metamizole (dipyrone) in cats following three different routes of administration

This study was performed to determine pharmacokinetic profiles of the two active metabolites of the analgesic drug metamizole (dipyrone , MET), 4‐methylaminoantipyrine (MAA), and 4‐aminoantipyrine (AA), after intravenous (i.v., intramuscular (i.m.), and oral (p.o.) administration in cats. Six healthy mixed‐breed cats were administered MET (25 mg/kg) by i.v., i.m., or p.o. routes in a crossover design. Adverse clinical signs, namely salivation and vomiting, were detected in all groups (i.v. 67%, i.m. 34%, and p.o. 15%). The mean maximal plasma concentration of MAA for i.v., i.m., and p.o. administrations was 148.63 ± 106.64, 18.74 ± 4.97, and 20.59 ± 15.29 μg/ml, respectively, with about 7 hr of half‐life in all routes. Among the administration routes, the area under the plasma concentration curve (AUC) value was the lowest after i.m. administration and the AUC_EV/i.v. ratio was higher in p.o. than the i.m. administration without statistical significance. The plasma concentration of AA was detectable up to 24 hr, and the mean plasma concentrations were smaller than MAA. The present results suggest that MET is converted into the active metabolites in cats as in humans. Further pharmacodynamics and safety studies should be performed before any clinical use.     

俄罗斯黄花草木樨生物活性成分资源的分布与开发利用

为了查明生物活性成分在黄花草木樨根、茎、叶、子中的含量与分布特征,本研究重点开展了黄花草木樨活性成分的检测及田间开发试验。分别采用凯式定氮法和高效气相色谱法测蛋白质；氨基酸自动分析仪法测氨基酸；气相色谱-质谱、分子蒸馏仪检测脂肪酸；重量法检测皂苷与生物碱；高效液相色谱仪检测香豆素；福林试剂比色法检测多酚；蒽铜-硫酸比色法检测多糖；亚硝酸钠-硝酸铝-氢氧化钠比色法检测黄酮。按产量测算后,得出每公顷牧草生物活性成分的总产量为3016.3 kg/hm2。其中粗蛋白质、氨基酸和粗脂肪酸原料的产量分别为1400.6 kg/hm2,112.2 kg/hm2,1246.8 kg/hm2。有效成分皂苷、生物碱、多酚、香豆素的产量分别为97.0 kg/hm2、77.9 kg/hm2、41.7 kg/hm2、40.1 kg/hm2。上述成分经分离提取纯化后,可作为开发医药、食物、化工等生物技术产品的天然原料。本文为开发利用植物自然资源提供了新的途径。     

嗜线虫致病杆菌抗菌代谢产物Xcn1的研究进展

Xenocoumacin1（Xcn1）是嗜线虫致病杆菌产生的一种水溶性小肽类抗菌化合物，对真菌和细菌具有广谱的抑菌活性，在农业病害防治中具有良好的开发和应用前景。本文综述了Xcn1化合物的合成和降解机制、合成调控机制、抗菌作用机制以及防控植物疫病的研究进展，并展望了高产Xcn1生产菌株的改良和产业化应用前景。     

Potential Anti-Aging Substances Derived from Seaweeds

Aging is a major risk factor for many chronic diseases, such as cancer, cardiovascular disease, and diabetes. The exact mechanisms underlying the aging process are not fully elucidated. However, a growing body of evidence suggests that several pathways, such as sirtuin, AMP-activated protein kinase, insulin-like growth factor, autophagy, and nuclear factor erythroid 2-related factor 2 play critical roles in regulating aging. Furthermore, genetic or dietary interventions of these pathways can extend lifespan by delaying the aging process. Seaweeds are a food source rich in many nutrients, including fibers, polyunsaturated fatty acids, vitamins, minerals, and other bioactive compounds. The health benefits of seaweeds include, but are not limited to, antioxidant, anti-inflammatory, and anti-obese activities. Interestingly, a body of studies shows that some seaweed-derived extracts or isolated compounds, can modulate these aging-regulating pathways or even extend lifespans of various animal models. However, few such studies have been conducted on higher animals or even humans. In this review, we focused on potential anti-aging bioactive substances in seaweeds that have been studied in cells and animals mainly based on their anti-aging cellular and molecular mechanisms.     

纹党和红芪加工废弃物活性多糖对衰老小鼠的抗氧化作用

为了研究陇南道地中药材纹党和红芪加工废弃物中活性多糖对衰老小鼠的抗氧化作用，用低糖低脂饲料适应性喂养小鼠15 d，以剂量为500 mg·kg^-1颈部皮下注射D-半乳糖（D-galactose）溶液构建小鼠亚急性衰老模型。将建模成功的小鼠随机分为正常对照组、衰老模型组、纹党多糖（Codonopisis pilosula polysaccharides, CPP）、红芪多糖（Hedysarum polybotrys polysaccharides ,CHP）剂量处理组和阳性（V_E170 mg·kg^-1）处理组。连续灌胃给药28 d，研究两种多糖对衰老小鼠体重及动物脏器指数、血清中超氧化物歧化酶（SOD）、过氧化氢酶(CAT)和谷胱甘肽过氧化物酶(GSH-Px)的活力变化以及丙二醛（MDA）的含量变化。经过测定，提取的纹党多糖和红芪多糖得率分别为16.52%和13.96%，纯度为 99.65%和99.38%，剂量在400 mg·kg^-1时纹党多糖对衰老小鼠治疗效果明显优于红芪多糖，其心脏和脾脏指数、血清中的SOD、CAT和GSH-Px活力均高于模型组，血清中的MDA含量均低于模型组，对衰老小鼠具有缓解体重下降的作用。结果表明，纹党多糖和红芪多糖均能提高衰老小鼠的抗氧化作用，且纹党多糖和红芪多糖联用后抗氧化和抗衰老能力最好。     

水稻灌浆期穗颈瘟发生对产量及茎节代谢产物的影响

【目的】检测自然条件下稻瘟病感病品种茎节的代谢产物,从代谢物角度解析水稻品种感病和产量降低的原因,为粳稻品种感病机理研究和生态防控提供理论依据。【方法】以稻瘟病感病品种辽星1号和粳型恢复系C418为材料,灌浆期调查穗颈瘟发病率,同时采用气相色谱-质谱（GC-MS）非靶向代谢组学方法检测感病茎节和正常茎节的代谢产物,利用主成分分析（PCA）感病茎节与正常茎节之间代谢物组成,利用偏最小二乘法判别分析（PLS-DA）的变量权重值（VIP>1.0）进行两者之间差异代谢产物种类的筛选,比较两者糖类物质和氨基酸类物质的差异,从代谢物角度解析水稻品种产量降低的原因。成熟期进行结实率、千粒重、粒长、糙米率等产量和品质性状测定。【结果】辽星1号和C418穗颈瘟发病率分别为57.23%和82.94%。穗颈瘟显著降低一次枝梗整精米率、二次枝梗的结实率、千粒重、长宽比和整精米率,其他性状无显著差异。辽星1号和C418的茎节GC-MS检测均定性到358种代谢产物,感病茎节上调了73.46%和67.88%的代谢产物。PCA和PLS-DA分析可以将感病茎节和正常茎节的代谢产物清楚分开,辽星1号和C418的感病茎节和正常茎节之间具有明显不同的代谢产物表型,与正常茎节相比,辽星1号感病茎节诱导61种代谢产物相对含量显著变化,C418感病茎节诱导47种代谢产物相对含量显著变化,两个品种共有显著变化的代谢产物30种。其中,次生代谢产物香草酸、α-生育酚、脱氢抗坏血酸、三十烷醇、大豆苷元和N-乙酰-d-甘露糖胺的相对含量显著下调,辽星1号分别下调了87.03%、96.29%、77.95%、74.56%、86.48%和82.68%,C418分别下调了99.92%、99.68%、97.26%、86.67%、94.96%和76.74%。正常茎节中辽星1号这6种次生代谢产物的相对含量分别是C418的2.64、2.39、2.39、2.27、3.09和2.56倍;感病茎节上调了63.33%的糖类物质和68.42%的氨基酸类物质,糖类物质上调了1.02—17.92倍,氨基酸类物质上调了1.05—13.12倍,其中C418糖类物质上调的幅度更大。【结论】穗颈瘟发生显著改变了感病品种辽星1号和C418的茎节代谢产物组成,感病品种可能通过香草酸、α-生育酚、脱氢抗坏血酸、三十烷醇、大豆苷元和N-乙酰-d-甘露糖胺相对含量的变化调控茎节对稻瘟病的防御反应。感病茎节通过积累大量的糖类物质和氨基酸类物质,降低其向籽粒转运,抑制了产量形成。     

甲基营养型芽胞杆菌的研究进展

甲基营养型芽胞杆菌是一种无致病性的细菌,对外界环境具有多抗逆性,作为芽胞杆菌属的"后起之秀",被越来越多的应用于各行业中。本文主要从甲基营养型芽胞杆菌的生理生化特征、代谢产物及应用等方面论述其研究进展。