珊瑚姜油的抗氧化性

采用超临界CO2萃取珊瑚姜得到珊瑚姜油,添加到在烘箱强化保存条件下(60～65℃)的浓缩鱼油中,测定鱼油的过氧化值(POV),考察珊瑚姜油对浓缩鱼油的抗氧化能力;并用气相色谱-质谱联用仪(GC-MS)对珊瑚姜油进行分析,从化学组成探讨珊瑚姜油与BHT和VE对鱼油的抗氧化机理差异。结果表明：珊瑚姜油抗氧化效果优于BHT及VE,是一种良好的天然抗氧化剂,珊瑚姜油添加量为0.03%时对鱼油很好的保护作用;GC-MS方法鉴定出珊瑚姜油有44种成分：单萜类化合物13种,占25.12%;含氧单萜类化合物16种,占26.43%;倍半萜类化合物9种,占8.82%;含氧倍半萜、苯系衍生物及其他6种,占39.63%。     

Isolation and evaluation of the antioxidant activity of phenolic constituents of the Garcinia brasiliensis epicarp

A new glycosylated biflavonone, morelloflavone-4′″-O-β-d-glycosyl, and the known compounds 1,3,6,7-tetrahydroxyxanthone, morelloflavone (fukugetin) and morelloflavone-7″-O-β-d-glycosyl (fukugeside) were isolated from the epicarp of Garcinia brasiliensis collected in Brazil. The structures of these compounds were established using ¹H and ¹³C NMR, COSY, gHMQC and gHMBC spectroscopy. The compounds exhibited antioxidant activity. The greatest potency was displayed by morelloflavone (2), with IC₅₀ = 49.5 mM against DPPH and absorbance of 0.583 at 400 μg/mL for the reduction of Fe³⁺. The weakest potency was displayed by 1,3,6,7-tetrahydroxyxanthone (1), with IC₅₀ = 148 mM against DPPH and absorbance of 0.194 at 400 μg/mL for the reduction of Fe³⁺.     

黄酮类食用天然色素抗氧活性的研究

利用DPPH法对四种黄酮类食用天然色素的研究发现：它们都具有抗氧活性,有的可与BHT相比美,比紫外光谱和黄酮含量的分析说明了四种色素的抗氧活性与黄酮化合物含量及结构的关系,为进一步拓宽黄酮类食用天我色素的应用,提供科学依据。     

BHT反应工艺和设备的改进

ＢＨＴ是一种通用型抗氧剂,在工业生产装置中有连续和间歇两种反应工艺流程,小规模装置多采用间歇搅拌釜式反应器,但存在着单位反应器容积生产能力低,异丙烯单耗高的缺陷。作者在新装置设计中,通过反应工艺和动力学特性分析,对反应工艺和设备进行改进。生产实践验证,这一改进有效地克服了原间歇反应工艺的缺陷．     

防老剂BHT的提纯及其纯度检测

为提高和准确测定防老剂BHT的纯度,采用重结晶和区域熔融法对工业品防老剂BHT进行提纯,并用高效液相色谱仪和差示扫描量热仪对样品进行纯度检测。高效液相色谱法(HPLC)的标准曲线法测得的回收率在100.19%~100.28%之间,相对标准差(RSD)为0.05%;提纯品防老剂BHT的纯度为99.09%,RSD为0.08%。用差示扫描量热法(DSC)测得提纯品纯度为99.16%,RSD为0.14%。纯度达到国际同类产品水平。     

塑胶跑道抗老剂BHT在非固体原料中含量与成品中释放量关系探究

建立了气相色谱-质谱法测定塑胶跑道非固体原料中2,6-二叔丁基对甲苯酚(BHT)含量的测试方法,在(1～100)mg/L范围内,方法线性相关系数R²=0.99795,检出限为0.012g/kg,定量限为0.040g/kg,RSD在(1.29～2.56)%。将含有BHT的非固体原料制作成塑胶跑道成品,用GB 36246-2018中总挥发性有机化合物(TVOC)释放量测试方法测试BHT释放量。建立非固体原料中BHT含量与成品中BHT释放量的相关性,二者具有较好的线性关系,线性相关系数R²=0.96965。     

日粮添加BHT对饲喂氧化豆油黄羽肉鸡肌肉品质和抗氧化能力的影响

本试验旨在研究2,6-二叔丁基-4-甲基苯酚(BHT)对饲喂氧化豆油日粮黄羽肉鸡肌肉品质及抗氧化能力的影响。试验采用2×2因子设计,因素1为日粮中的豆油,按其品质分为新鲜豆油(MDA=13.4 nmol/mL)和氧化豆油(MDA=367.7 nmol/mL),因素2为日粮中BHT含量,按添加剂量分为两水平(0、125 mg/kg)。240羽1日龄优质黄羽肉鸡被随机分成4个处理组,每组6个重复,每个重复10只鸡。结果表明:与新鲜豆油组相比,氧化豆油组肌肉滴水损失和丙二醛MDA含量显著增加(p<0.05);肌肉内还原型谷胱甘肽(GSH)含量、总超氧化物歧化酶(T-SOD)活力和肌肉总抗氧化能力(T-AOC)显著降低(p<0.05);腿肌肌肉中γ-谷氨酰半胱氨酸合成酶调节亚单位(γ-GCLm)和γ-谷氨酰半胱氨酸合成酶催化亚单位(γ-GCLc)的mRNA表达量显著降低(p<0.05)。与不含BHT日粮组相比,日粮中添加125 mg/kg BHT能够显著降低肌肉中MDA含量、肌肉滴水损失及蒸煮损失(p<0.05),能够显著提高肌肉T-SOD和CAT酶活(p<0.05),显著提高肌肉中CAT和γ-GCLm的mRNA表达量(p<0.05)。结论:日粮中添加BHT能够通过提高黄羽肉鸡机体抗氧化能力,改善肉品质,缓解氧化豆油造成的氧化损伤。     

Screening of antioxidative properties of the methanolic extracts of Pelargonium endlicherianum Fenzl., Verbascum wiedemannianum Fisch. & Mey., Sideritis libanotica Labill. subsp. linearis (Bentham) Borm., Centaurea mucronifera DC. and Hieracium cappadocicum Freyn from Turkish flora

Five extracts from five plants, of which four are endemic to Turkish flora, were screened for their possible in vitro antioxidant activities by two complementary test systems, namely DPPH free radical-scavenging and β-carotene/linoleic acid. In the first case, Pelargonium endlicherianum extract exerted greater antioxidant activity than those of other plant extracts studied with an IC₅₀ value of 7.43 ± 0.47 μg/ml, followed by Hieracium cappadocicum (30.0 ± 0.14 μg/ml). When compared to the synthetic antioxidant BHT (18.0 ± 0.40 μg/ml), the methanolic extract of P. endlicherianum exhibited more than two fold greater antioxidant activity. In the β-carotene/linoleic acid test system, the most active plant was P. endlicherianum with 72.6% ± 2.96 inhibition rate, followed by H. cappadocicum (55.1% ± 2.33) and Verbascum wiedemannianum (52.5% ± 3.11). Antioxidant activities of curcumin and ascorbic acid were also determined as positive controls in parallel experiments.     

乙醚稳定剂的研究

用ＢＨＴ作为乙醚稳定剂,应用于试剂乙醚、工业乙醚、麻醉乙均有比一般乙醚稳定剂更显著的稳定效果,而且基本上不影响乙醚产品的其它质量指标。     

高效液相色谱法测定植物油中TBHQ、BHA和BHT方法优化研究

优化了农业部标准NY/T1602-2008中色谱条件和样品前处理过程,建立以空白植物油预先溶解标样,以甲醇为提取剂,通过液相色谱法同时测定植物油中TBHQ、BHA、BHT的方法。该方法前处理简单、经济环保、检测快速准确,有效解决了农业部标准NY/T1602-2008方法回收率偏低的问题,有助于日常检测中快速、准确测定植物油中TBHQ、BHA、BHT含量。