Mitochondrial Associated Yeast Flocculation ‐The Effect of Acetylsalicylic Acid

Mitochondrial function is generally accepted as important for expression of yeast flocculation. In this study, a correlation between mitochondrial activity and flocculation is demonstrated using the XTT reduction assay. The mitochondrial activity of strongly flocculent cells was higher than those of weakly flocculent cells and cells cultivated in the presence of acetylsalicylic acid. Furthermore, we show the first oxylipin‐containing flocculation binding sites on yeast cell surfaces using scanning electron microscopy. We propose that in addition to zymolectin‐mediated flocculation, oxylipin interactions may also play a role in yeast flocculation.     

Comparison of total antioxidant capacity and phenolic composition of some apple juices with combined HPLC–CUPRAC assay

It was aimed in this study to identify and quantify various constituents (particularly phenolics) of apple juice and to quantitatively compare the total antioxidant capacities of juices obtained from apple varieties grown in Turkey.     

HPLC测定盐酸奥洛他定滴眼液中苯扎氯铵的含量

目的建立HPLC测定盐酸奥洛他定滴眼液中苯扎氯铵含量的方法。方法以氰基键合硅胶为填充剂;乙腈-水-三乙胺为440∶560∶1,用磷酸调pH 3.4为流动相,流速1.0 mL/min;检测波长210 nm。结果苯扎氯铵在0.05～0.15 mg/mL范围内呈良好的线性关系(r=0.999 8);平均回收率99.7%(n=9,RSD=0.69%)。结论此方法简便灵敏准确,重复性好,可用于测定盐酸奥洛他定滴眼液中苯扎氯铵的含量。     

厚叶海带岩藻聚糖硫酸酯分离纯化及其体外肿瘤抑制活性研究

本研究以日本厚叶海带（Kjellmaniella crassifolia）中提取的岩藻聚糖硫酸酯（Fuciodan）为原料,采用DEAESepharose Fast Flow弱阴离子交换柱层析分离纯化,通过苯酚-硫酸法和氯化钡-明胶法检测各组分中多糖及硫酸根（SO₄²）含量,MTT法分析50、200、800μg/m L的日本厚叶海带岩藻聚糖硫酸酯粗品（F）及分离组分对肝癌细胞Hep G2、肺癌细胞A549和结肠癌细胞HT-29细胞存活率影响。研究结果表明,DEAE-Sepharose Fast Flow弱阴离子交换柱对粗品F的分离纯化效果良好,可以得到5个组分（F-0、F-1、F-2、F-3和F-4）;组分F-4多糖与SO₄^2-含量最高,分别为64.25%和26.32%。MTT实验结果显示,岩藻聚糖硫酸酯粗品及各分离组分对三种肿瘤细胞均具有肿瘤抑制活性,不同组分对HepG2、A549、HT-29的最低细胞存活率分别为67.69%、56.03%和27.56%。基于以上研究结果,表明日本厚叶海带岩藻聚糖硫酸酯具有很大的发展潜力,开发成为一种有效的天然抗肿瘤药物。      

乳品行业企业现状及竞争态势战略分析

对乳品行业的企业基本情况及竞争格局的现状进行了分析,介绍了乳品行业中资本介入的现状与发展趋势,说明了乳品企业在市场开拓、产品创新等方面竞争的同时,还受到资本市场的挑战,同时用迈克尔·波特的五力模型方法(五种力量框架)对每种力量进行分析,并对影响行业的重要经济因素进行了系统性的评估,从而对乳业的竞争态势进行了论述,提出资本运作已成为企业生存与发展的战略选择。     

Antioxidant activity and phenolic content of phenolic rich fractions obtained from black cumin (Nigella sativa) seedcake

The antioxidant activities of crude methanolic extract (CME) and its fractions using ethyl acetate (EAF), hexane (HF) and water (WF) of black cumin seedcake were investigated. DPPH radical scavenging activity, β-carotene–linoleate bleaching, and inhibition of corn oil oxidation were used to evaluate the antioxidant capacity. The total phenolics were found to be 78.8, 27.8, 32.1 and 12.1 mg gallic acid equivalents (GAE)/g in EAF, CME, WF and HF, respectively. The CME and EAF exhibited the highest DPPH followed by WF and HF. The extract/fractions showed high effect on reducing the oxidation of β-carotene. The effect of extract/fractions on the oxidative stability of corn oil at 70 °C was tested in the dark and compared with butylated hydroxyanisole (BHA). The oil peroxide and anisidine values were generally lower with addition of PRFs in comparison to a control. The predominant phenolic compounds identified by HPLC–DAD in CME and WF of black cumin seedcake were hydroxybenzoic, syringic and p-cumaric acids.     

环丙沙星衍生物的制备及其抗体特异性研究

本文研究了环丙沙星(CPLX)羧基衍生物及其抗体的制备,并对该衍生物抗体的特异性进行了测定。将环丙沙星与3-溴丙酸反应,生成环丙沙星的羧基衍生物(CPLX-COOH),通过制备液相进行纯化,用红外光谱(IR)、电喷雾电离质谱(ESI-MS)与核磁共振法(NMR)进行鉴定;将环丙沙星衍生物分别与牛血清白蛋白(BSA)和卵清蛋白(OVA)进行偶联,分别制备免疫抗原(CPLX-COOH-BSA)和包被抗原(CPLX-COOH-OVA),并用紫外光谱法进行鉴定。用免疫抗原免疫BALB/c小鼠,制备环丙沙星衍生物多克隆抗体。通过ELISA方阵滴定法,确定包被抗原的最佳包被浓度和抗体最佳稀释度,建立了CPLX-COOH间接竞争ELISA检测方法,其半抑制浓度IC50为228.56 ng/mL,最低检出限(LOD)为25.527 ng/mL,该抗体具有广谱特异性,可与多种氟喹诺酮类药物发生交叉反应,可进行氟喹诺酮类药物残留的多元检测。     

火试金重量法测定导电银浆中银量

报导运用火试金重量法测定导电银浆中银含量的方法。考察了称样载体、焙烧温度、铅箔用量、灰吹温度对银含量分析结果的影响,结果表明样品用铅箔作称重载体,250 ℃焙烧,15 g铅箔包裹,900 ℃灰吹是比较理想的方案。实验称取与样品中银量相当的金属银按试样的测定步骤和环境条件分析,银量的回收率作为补正因子k对试样分析结果进行补正。方法回收率为99.6 %～100.2%。对实际样品进行分析,测定值与推荐值相一致,相对标准偏差为0.51%和0.71 %（n=5）。