青稞提取物干预对老年小鼠骨骼肌萎缩的影响

衰老过程中氧化应激的增加与骨骼肌质量与功能的显著降低存在密切关联。青稞富含多酚、类黄酮等生物活性成分,具有较强的抗氧化活性。研究表明,膳食中的天然抗氧化成分可以有效缓解骨骼肌增龄性萎缩。为探讨青稞水提物和醇提物是否对老年小鼠骨骼肌萎缩产生影响,测定了12周青稞提取物干预对老年小鼠骨骼肌年龄相关生理变化的影响,并利用反转录聚合酶链反应和免疫蛋白印记测定了肌萎缩标志基因、氧化应激相关基因的表达。实验结果表明:与衰老的对照小鼠相比,两种青稞提取物干预均有效抑制了衰老小鼠骨骼肌肌肉质量的减少,并增强了衰老小鼠的运动能力；青稞提取物在mRNA和蛋白水平均显著降低了肌肉环状指基因1和肌肉萎缩盒F基因的表达；青稞提取物激活了SIRT3蛋白的表达,并显著抑制了衰老小鼠骨骼肌中的氧化应激。研究结果表明,青稞提取物可以通过激活SIRT3信号的表达有效抑制衰老诱导的氧化应激,从而缓解衰老导致的骨骼肌萎缩。     

Antioxidant properties of water and ethanol extracts from hot air-dried and freeze-dried daylily flowers

Daylily (Hemerocallis fulva Linn.) flowers were hot air-dried and freeze-dried after harvest. Water and ethanol extracts were prepared from these dried flowers and their antioxidant properties were evaluated using total antioxidant activity, reducing capacity, metal chelating activity, and DPPH and superoxide anion radical scavenging activities, comparing with standards. Extracts from daylily flowers exhibited strong antioxidant activity. Ethanol was more efficienct to extract antioxidants than water and that freeze-drying preserved higher activities than air-drying. Ethanol extract from freeze-dried daylily flowers showed the highest antioxidant activity and phenol content.     

橘霉素免疫牛蛙肌肉蛋白柱的制备及其吸附橘霉素作用分析

用橘霉素人工抗原-佐剂免疫牛蛙,研究牛蛙肌肉蛋白质对橘霉素结合能力的大小。将能与橘霉素结合的蛋白质用海藻酸钠制粒。取6.4?mg橘霉素人工抗原免疫牛蛙肌肉蛋白质,使用海藻酸钠质量浓度4?g/100?mL、氯化钙质量浓度5?g/100?mL、戊二醛交联体积分数0.2%、交联时间2?h,制备海藻酸钙包埋蛋白质凝胶微球。取海藻酸钙凝胶微球2?g装填成固相小柱,以2?mL红曲米橘霉素提取液过柱,以20?mL超纯水洗脱杂质,与市售免疫亲和柱色谱图比较,均没有杂质干扰峰。以橘霉素标准液作为上样液,以70%乙腈-三氟乙酸作为橘霉素洗脱液,洗脱剂量为5?mL,回收率为86.7%,柱容量为0.101?μg/g。采用自制的牛蛙免疫蛋白柱和市售免疫亲和柱测得红曲米中橘霉素含量分别为0.037?μg/g和0.043?μg/g。     

High temperature reduction of metmyoglobin in aqueous muscle extracts

Oxymyoglobin in aqueous extracts of fresh beef longissimus dorsi muscles was initially oxidised to metmyoglobin during heat treatments at temperatures in the range 50-70?°C. The metmyoglobin then underwent reduction to a red pigment that was shown spectrally to be identical to oxymyoglobin. The formation of oxymyoglobin involved a heat induced precipitate that when removed from the solution, allowed oxidation to metmyoglobin to occur. However, on re-addition of the precipitate further reduction to oxymyoglobin took place. Dialysis of the muscle extract prior to heating markedly inhibited the reduction but addition of NADH to the dialysate permitted further reduction. The precipitate plus NADH caused oxymyoglobin formation in the presence of metmyoglobin but neither the precipitate nor NADH alone induced this formation. It is concluded that the initial conversion of oxymyoglobin to metmyoglobin on heating fresh beef muscle extracts was reversible and that the reverse reaction depended on the presence of both NADH and a muscle protein.     

芫荽抑菌成分的提取及其抑菌性能的研究

分别用石油醚、95%乙醇、水浸提芫荽,获得浸提液。抑菌实验表明,水提液对不同细菌均有明显的抑制作用,其最低抑菌浓度都为10%原液。采用沉淀蛋白、分离多糖、超滤、纳滤、离子交换等方法分离水提液组分,证明芫荽中主要抑菌成分是相对分子质量在500～3000的水溶性非肽类物质。     

Antioxidant properties of various solvent extracts from wild ginseng leaves

Water, methanol and ethanol extracts of freeze-dried leaves of wild ginseng were examined for their antioxidant properties. All leaf extracts were capable of free radicals scavenging activity. Among solvent extracts of wild ginseng leaves, ethanol extract showed the highest DPPH, hydroxyl radical scavenging and ferrous ion chelating activity. Otherwise, the highest superoxide radical scavenging activity was found in water extract followed by ethanol and methanol extracts of wild ginseng leaves. Ethanol extracts contained more phenolics (2333.2 mg/100 g) and flavonoids (1199.1 mg/100 g) than other extracts. These differences in concentrations of key antioxidants among various solvent extracts seemed to be responsible for their differences in antioxidant activities. When various solvent extracts were hydrolysed by acid, two aglycons of flavonoid, quercetin and kaempferol, were detected. According to the results obtained from this study, wild ginseng leaves showed marked antioxidant activities due to their abundant antioxidants.     

Cellular signaling pathways regulating the initial stage of adipogenesis and marbling of skeletal muscle

Due to extensive efforts to increase lean growth, intramuscular fat (marbling) is reducing in beef, pork and chicken breast, which impairs the eating quality of meat. Because fat is the major contributor to meat flavor, the presence of intramuscular fat is indispensible for the high eating quality of meat. However, up to now, our understanding of adipogenesis (formation of fat cells) in skeletal muscle is limited. Adipocyte differentiation in skeletal muscle initiates from multipotent mesenchymal stem cells, which are abundant in skeletal muscle at early developmental stages. In this review, the known cellular mechanisms regulating adipogenesis from multipotent cells are summarized, which include hedgehog, Wingless and Int (Wnt)/β-catenin, and bone morphogenesis protein (BMP) mediated signaling pathways, as well as AMP-activated protein kinase. Promoting adipogenesis within skeletal muscle will effectively increase intramuscular fat, improving the quality of meat.     

牛骨骼肌肌钙蛋白T单克隆抗体的制备及其特性鉴定

制备牛骨骼肌肌钙蛋白T的单克隆抗体,评价单抗的特性。肌肉提取物经聚丙烯酰氨凝胶电泳(sodium dodecyl sulfate polyacrylamide gel electrophoresis,SDS-PAGE)后切胶,用于免疫Balb/c小鼠。经聚乙二醇(polyethylene glycol,PEG)法融合,制备稳定分泌抗体的杂交瘤细胞株。用酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)方法对单抗的效价、亚型、特异性等进行分析。经筛选后,获得2株稳定分泌抗体的杂交瘤细胞株,其中3A8特异性好、效价高,为IgG1亚型,亲和常数为8.1×10~8L/mol。免疫印迹结果显示该单抗能与牛羊的骨骼肌提取物反应,不与鸡鸭的骨骼肌提取物反应。     

Antioxidant properties of aqueous and methanol soy extracts in minced trout muscle

Antioxidant capacity of freeze-dried aqueous and methanolic extracts of soy protein isolate (SPI) and soybean meal (SBM) were assessed by 2, 2′-Diphenyl-1-picrylhydrazyl (DPPH) assay and total phenolic content (TPC). Caffeic and chlorogenic acids in liquid aqueous extracts, and genistein and daidzein in liquid methanolic extracts were measured by HPLC. Freeze-dried extracts were applied (1000 and 4000 μg/g) to trout mince and TBARS formation monitored during 14 days refrigerated storage. SBM aqueous extracts-treated mince (4000 μg/g) had significantly lower (P < 0.05) TBARS than all other treatments. SPI methanolic extract had the highest TPC (100 mg chlorogenic acid equivalents/100 g extract) and genistein and daidzein contents. SPI aqueous extracts had the highest chlorogenic acid (280 μg/g) while SBM aqueous extracts had the highest caffeic acids content (484 μg/g). SPI had the best in vivo antioxidant profile. SBM extracts were most effective at retarding lipid oxidation in refrigerated trout mince.     

In-Vitro Protein Digestibility of Dehydrated Protein Extract from Poultry Bone Residue

In-vitro protein digestibility of freeze- or spray-dried protein obtained from poultry bone residue by alkali extraction was evaluated by a multienzyme procedure. Digestibility of the dehydrated extracts was significantly lower than chicken breast muscle or mechanically de-boned poultry. Digestibility of the spray-dried extracts was about 3% higher than freeze-dried extracts.     

人参浸提液处理对烧鸡食用品质的影响

为研制高品质的营养保健人参烧鸡产品,探究人参对烧鸡脂肪和蛋白氧化的抑制作用及食用品质的影响规律,以烧鸡为研究对象,探讨不同种类和不同添加量的人参对烧鸡的剪切力、pH值、出品率、色泽、质构、蛋白质羰基含量、蛋白质巯基含量、硫代巴比妥酸反应物质（thiobarbituric acid reaction substances,TBARS）值和感官评分等品质特性的影响。结果表明：红参浸提液的总皂苷含量最高,其对1,1-二苯基-2-三硝基苯肼自由基清除能力及2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除能力最强;林下参浸提液中多酚和黄酮含量最高;随着人参添加量的增加,烧鸡的硬度与咀嚼性增强,L*、a*、b*值和巯基含量明显增加,TBARS值与羰基含量显著降低（P＜0.05）;人参添加量相同时,红参浸提液对烧鸡羰基及巯基含量的影响最大（P＜0.05）,白参浸提液处理烧鸡的TBARS值最高;烧鸡的感官评分随着人参添加量的增加先显著增大后显著降低（P＜0.05）,在添加量为1.0%时感官综合评分最高。因此,适当地加入人参浸提液可以改善烧鸡的色泽,提高烧鸡的食用品质,抑制脂肪与蛋白氧化,其中红参浸提液的作用效果最佳。     

Monoclonal Antibody-based ELISA for Assessment of Endpoint Heating Temperature of Ground Pork and Beef

ABSTRACT: :
An indirect enzyme-linked immunosorbent assay (ELISA) using monoclonal antibody (MAb) 2F8 specific to a mammalian muscle protein was developed to evaluate the endpoint heating temperature (EPT) in ground pork and beef. The ELISA response of MAb 2F8 with meat extracts increased rapidly as the EPT increased from 60 to 80 °C and leveled off above 80 °C. Results of immunoblot revealed that the 12 kD antigenic thermo-stable muscle protein, which is common in both pork and beef, can be used as an EPT indicator for heat-processed pork and beef based on changes in the ratio of this protein to total soluble proteins in the meat extract which occurs at the EPT.     

天麻水提物活性成分分析及其抗氧化活性

目的:测定天麻水提物中营养成分含量及其抗氧化活性。方法:采集湿天麻,炮制后烘干粉碎,热水回流提取,脱色,冷冻干燥得到天麻水提物干粉,进而测定天麻水提物中水分、灰分、淀粉、粗蛋白、粗脂肪、总多糖、碳水化合物、总多酚、总黄酮、原花青素和天麻素等成分含量,并通过4种方法评价了天麻水提物的抗氧化活性。结果:天麻水提物中水分、灰分、淀粉、粗蛋白、粗脂肪、总多糖和碳水化合物的含量分别是4.60、1.55、40.30、9.21、4.01、38.24、79.80 g/100 g,矿物质中钾元素的含量最高,为25477.45 mg/kg;天麻水提物中总多酚、总黄酮和原青花素含量分别为17.0、9.0、3.3 mg/g,天麻素和对羟基苯甲醇的含量为2.87%和0.64%。通过超高效液相色谱(Ultra Performance Liquid Chromatography,UPLC)检测到7种多酚成分,其中荭草素的含量最高,为161.96 mg/100 g。天麻水提物具有一定的还原能力和对自由基的清除能力,且随着提取物浓度的升高,其还原力和对自由基的清除能力以剂量依赖性方式增强。在实验范围内其最大浓度的抗氧化活性最强,其中天麻水提物浓度为0.2、10、1、0.1 mg/mL时,总还原力、DPPH·清除率、OH·清除率、O₂-·清除分别达到1.05、90%、76%和58%。结论:天麻水提物具有较高的营养价值和一定的抗氧化活性,开发和应用前景广阔。     

Potato Peel Waste: Stability and Antioxidant Activity of a Freeze-Dried Extract

Aqueous extracts of potato peel waste were freeze-dried. High performance liquid chromatography (HPLC) of the freeze-dried extracts revealed that chlorogenic (50.31%), gallic (41.67%), protocatechuic (7.81%), and caffeic (0.21%) acids were the major phenolics. During 15 days storage of the freeze-dried extract, no degradation of phenolics occurred. After 4 days storage at 63°C, 5.00g of sunflower oil containing either the freeze-dried extract (200 ppm) or butylated hydroxyanisole (BHA) (200 ppm) reached peroxide values (PV) of 37.38 and 37.47 meq kg^-1 respectively. L-ascorbic acid-6-palmitate was the best antioxidant (PV= 10.65 meq kg^-1) but the freeze-dried extract was as good as BHA.     

Anti-oxidant,anti-proliferative and anti-inflammatory activities of the extracts from black raspberry fruits and wine

The purpose of the study was to determine polyphenols, anthocyanins and ascorbic acid in the extracts of black raspberry fruits and wine, along with their anti-oxidant, anti-proliferative and anti-inflammatory activities. Black raspberry fruits without or with seeds crushed were blended in 60% ethanol (FE and FES, respectively) or in water (FW and FWS, respectively). Black raspberry wine without or with seeds crushed (W and WS, respectively) were prepared. Polyphenol content was the highest in the FES (8.25 mg/g fruit). Generally the ethanol extracts with seeds crushed showed higher anti-oxidant activities with the lowest DPPH IC₅₀ (130 μg/ml (freeze-dried extract/reaction solution)) for the FES and the lowest ABTS IC₅₀ (198 μg/ml) for the WS. Cell viabilities were reduced by 13–70% when treated with 100 μg/ml (freeze-dried extract/medium) for HT-29 cells and 1000 μg/ml for LNCaP cells. The FES most actively suppressed nitric oxide production in LPS-stimulated RAW264.7 cells (p < 0.05). Superoxide dismutase and glutathione peroxidase activities treated with the extracts were higher than the control (p < 0.05).     

Water binding of proteins in the processing frankfurter-type sausages Part. 1. Water-binding ability of freeze-dried meat fractions containing myofibrillar and stromal proteins

As soon as possible and 48 h after slaughter respectively, from both blade-bone muscle groups of cattle and pig carcasses the ?thick pieces”? were excised, extracted, and fractionated. Residues and precipitates from water and salt extracts resulted were freeze-dried, and an improved Baumann capillary suction apparatus was used to measure their water binding capacity (WBC) with and without addition of 2% sodium chloride and/or heating to 80 °C. With one exception the WBC results followed a relative pattern demonstrating the final residues (stromal proteins and leavings of myofibrillar proteins) binding the highest amount of added water, precipitates of dialysis (mainly containing myofibrillar proteins) a remarkable amount and powdered meats the least. As scanning electron micrographs confirmed, there were no fibrous structures in the precipitates resulted from dialysis of salt solutions (1.0 mol/1). Heating decreased the spontaneous water uptake of all fractions. Addition of sodium chloride had only a noticeable capillary-suction and swelling effect on unheated samples. Hence swelling of undissolved protein structures (extraction of myosin and possibly of actomyosin) is therefore not the only way for water binding in frankfurter-type sausages.     

Water binding of proteins in the processing frankfurter-type sausages. Part. 1. Water-binding ability of freeze-dried meat fractions containing myofibrillar and stromal proteins

As soon as possible and 48 h after slaughter respectively, from both blade-bone muscle groups of cattle and pig carcasses the "thick pieces" were excised, extracted, and fractionated. Residues and precipitates from water and salt extracts resulted were freeze-dried, and an improved Baumann capillary suction apparatus was used to measure their water binding capacity (WBC) with and without addition of 2% sodium chloride and/or heating to 80 degrees C. With one exception the WBC results followed a relative pattern demonstrating the final residues (stromal proteins and leavings of myofibrillar proteins) binding the highest amount of added water, precipitates of dialysis (mainly containing myofibrillar proteins) a remarkable amount and powdered meats the least. As scanning electron micrographs confirmed, there were no fibrous structures in the precipitates resulted from dialysis of salt solutions (1.0 mol/1). Heating decreased the spontaneous water uptake of all fractions. Addition of sodium chloride had only a noticeable capillary-suction and swelling effect on unheated samples. Hence swelling of undissolved protein structures (extraction of myosin and possibly of actomyosin) is therefore not the only way for water binding in frankfurter-type sausages.     

Improvement of nutritional value of common beans (Phaseolus vulgaris) by autoclaving or extraction

Larval weight of Tribolium castaneum was used to evaluate six varieties of common beans (Phaseolus vulgaris). Beans incorporated into test diets were raw, autoclaved, or extracted with either water or 80% methanol. All treatments improved the nutritional quality of beans when compared to raw beans. The bean extracts were growth depressing. In another study heating of the freeze-dried water extract of black beans improved its nutritive value but not of the methanol extract. Tribolium castaneum larvae may be used to evaluate the nutritional quality of Phaseolus vulgaris and different bean treatments.     

Production and Characterization of Monoclonal Antibodies Specific to Pangasius Catfish, Basa, and Tra

ABSTRACT:  Four IgG (subclass IgG1) class monoclonal antibodies (MAbs) strongly reactive to Asian farm-raised Pangasius catfish, tra ( Pangasius hypophthalmus ) and basa ( Pangasius bocourti ), have been developed. These MAbs were raised by immunizing an animal with thermal-stable crude sarcoplasmic protein extract of cooked tra. The MAbs were selected by screening hybridoma clones against more than 70 common fish and meat protein extracts. Two MAbs, T7E10 and T1G11, were found to be specific to the Asian Pangasius catfish, tra, and basa, with no cross-reactions with any of the common fish and meat species or with the food additive proteins (bovine serum albumin, soy proteins, milk proteins, egg proteins, and gelatin) tested. MAb T7E10 recognized 2 antigenic proteins (molecular weight approximately 36 and 75 kDa) in raw and cooked tra and basa extracts, while T1G11 bound to several proteins (molecular weight between 13 and 18 kDa) in tra and basa extracts. Two other MAbs, F7B8 and F1G11, recognized a common protein (36 KDa) and cross-reacted with all the fish extracts tested and with several mammalian species. These MAbs can be employed individually or in combination in various formats of immunoassays for rapid identification of Pangasius catfish, either raw or cooked. They can also be used to study the biological, biochemical, and physiological aspects of thermal-stable antigenic proteins. This is the first study identifying these thermal-stable antigenic proteins present in Pangasius catfish as species-specific biomarkers.     

冬瓜提取物抗小鼠胃溃疡活性研究

冬瓜(B.hispida)是中国的一种常见的蔬菜，本文探讨了冬瓜的不同提取物在抑制乙酰水杨酸所致的小鼠实验性胃溃疡上的活性。冬瓜首先经过脱水再用甲醇萃取并将提取物真空浓缩，然后将提取物中可溶于正丁醇和水的部分分离出来冷冻干燥后用于动物实验。口服不同剂量提取物的小鼠，溃疡的发生率明显的降低了。病理切片的结果表明这些提取物可以保护胃粘膜上皮细胞并抑制溃疡发生。由于冬瓜是一种常见的无毒植物，它与现有的抗胃溃疡的药物相比具有明显的优势，因而在功能食品方面的应用前景非常广阔。