鱼腥草浸泡酒的工艺研究

利用高效液相色谱（HPLC）和紫外可见分光仪（UV）,以黄酮（山奈酚-3-O-葡萄糖苷、芦丁、金丝桃苷、槲皮苷、槲皮素、山奈素和异鼠李素）和多酚为考察指标,以乙醇体积分数、液固比和浸泡时间3个因素进行响应优化,研究鱼腥草泡酒的最佳工艺。结果表明,鱼腥草浸泡酒的最佳提取工艺为乙醇55%vol、液固比10∶1（mL/g）、存放时间40 d,山奈酚-3-O-葡萄糖苷、芦丁、金丝桃苷、槲皮苷、槲皮素、山奈素和异鼠李素和多酚理论含量分别为333.6 mg/L、157.4 mg/L、67.3 mg/L、137.3 mg/L、44.8 mg/L、161.7 mg/L、54.6 mg/L和1920.6 mg/L。     

HPLC法同时测定枣叶中5种黄酮的含量

建立了一种枣叶中黄酮类成分定量分析的HPLC方法,并对14个品种的大枣及酸枣叶中这5种黄酮的含量进行了分析。结果得到采用Hypersil BDS C18色谱柱,以乙腈与0.1%甲酸水溶液为流动相梯度洗脱,流速1 m L/min,柱温30℃,检测波长360 nm,实现了槲皮素-3-O-洋槐糖苷、芦丁、槲皮素-3-O-β-D-葡萄糖苷、山奈酚-3-O-芸香糖苷、槲皮素-3-O-α-L-阿拉伯糖-(1→2)-α-L-鼠李糖苷5种黄酮苷的同时检测,最低检出限为1.44~2.59μg/m L,加标回收率在93.8%~105.9%之间。5种黄酮苷的含量测定结果表明不同品种的枣叶中黄酮类成分的组成和含量差异较大,其中芦丁和槲皮素-3-O-洋槐糖苷的含量较高,平均为7.83 mg/g D.W和4.61 mg/g D.W;8个品种枣叶中检测到槲皮素-3-O-α-L-阿拉伯糖-(1→2)-α-L-鼠李糖苷,平均5.32 mg/g D.W;而槲皮素-3-O-β-D-葡萄糖苷和山奈酚-3-O-芸香糖苷的含量较低,分别为0.14 mg/g D.W和0.41 mg/g D.W。     

甜叶菊花和叶中酚类成分分析及含量测定

以高效液相色谱-串联四极杆质谱分析仪,结合质谱分析及比对对照品或文献报道化合物的保留时间和质谱参数,在甜叶菊花和叶中鉴定了16种酚类化合物。建立一种利用高效液相色谱法测定甜叶菊中16种酚类化合物含量的方法,并对甜叶菊一新品种盛花期花和叶中酚类的含量进行测定。结果表明,甜叶菊花和叶中酚酸化合物以新绿原酸、绿原酸、隐绿原酸、异绿原酸B、异绿原酸A、异绿原酸C为主,异绿原酸A含量最高,绿原酸含量次之;花和叶中类黄酮化合物主要为芦丁、槲皮素-7-O-葡萄糖苷、木犀草素-7-O-葡萄糖苷、木犀草素-7-O-芸香糖苷、槲皮素-3-O-木糖苷、槲皮素-3-O-鼠李糖苷、芹菜素-7-O-葡萄糖苷、山奈酚-3-O-阿拉伯糖苷、山奈酚-3-O-鼠李糖苷,槲皮素-3-O-鼠李糖苷含量最高;盛花期甜叶菊花和叶中酚类总量达（22.31±0.51）mg/g和（91.11±2.32）mg/g。     

月桂叶中黄酮类成分的分析鉴定

利用液相色谱-四级杆-飞行时间串联质谱(LC-Q-TOF-MS),结合标准品比较、保留时间对比、多级质谱碎片和相关文献,鉴定了月桂叶黄酮的化学成分。利用液相-三重四级杆串联质谱(LC-MS/MS)在多反应监控模式(MRM)下,分别测定了黄酮化合物的含量。从我国月桂叶中分离鉴定出了16种黄酮化合物,包括牡荆素鼠李糖苷(1658.53μg/g±56.9)、芦丁(19883.54±494.33μg/g)、牡荆素(4430.87±89.72μg/g)、A-型原花青素三聚体(2281.88±78.90μg/g)、表儿茶素(148.10μg/g±2.32)、山奈酚-3-O-芸香糖苷(3491.02±47.98μg/g)、异鼠李素-3-O-芸香糖苷(6643.78±99.04μg/g)、金丝桃苷(11979.66±317.79μg/g)、山奈酚-7-O-葡萄糖苷(738.55μg/g±10.86)、紫云英苷(508.60μg/g±6.96)、槲皮素-3-O-木糖苷(2044.22μg/g±57.65)、异鼠李素-3-O-葡萄糖苷(2079.94μg/g±76.38)、槲皮苷(2079.94μg/g±61.84)、山奈酚-3-O-鼠李糖苷(6412.37±78.65μg/g)、槲皮素(1629.45μg/g±47.65)和山奈酚(364.29μg/g±2.84)。测定了月桂叶黄酮提取物清除DPPH自由基的能力,结果证明,月桂叶黄酮具有良好的清除自由基能力。     

超高效液相色谱-质谱联用技术解析黑果枸杞超临界CO_2萃取物中黄酮类天然产物结构

以青海柴达木黑枸杞为研究材料,对其超临界CO2萃取物,采用超高效液相色谱-质谱联用技术和PeakView色谱工作站拟合进行分析,并通过二级质谱解析和紫外光谱及质谱数据比对,阐明其中的黄酮组分及其结构。共鉴定出黑果枸杞果的超临界CO2萃取物中含有13种黄酮类化合物(7种黄酮醇苷元及黄酮醇苷,3种二氢黄酮醇苷元,2种黄酮苷元和1种二氢黄酮苷元),包括芦丁、槲皮素-3-β-葡萄糖醛酸苷、金丝桃苷即槲皮素-3-O-吡喃半乳糖苷、二氢槲皮素、二氢异鼠李素、二氢山柰酚、槲皮素、芹菜素、橙皮素、苜蓿素、山柰酚、异鼠李素和山柰素,其中橙皮素和苜蓿素在黑果枸杞成分研究中未被发现过。     

荞麦类黄酮成分的含量测定与分析研究

目的 建立高效液相色谱法同时测定荞麦中芦丁、金丝桃苷、山奈酚-3-O-芸香糖苷、槲皮素、芹菜素和山奈酚6种黄酮成分的含量, 并比较分析不同产地荞麦中黄酮类成分差异情况。方法 荞麦样品加入 20 mL体积分数为80%甲醇水溶液超声辅助提取。高速离心后, 经Shiseido CAPCELL PAK C18 MGⅡS5色谱柱(4.6 mm×250 mm, 5.0 μm), 以乙腈-0.1%磷酸水溶液为流动相, 梯度洗脱; 流速为1.2 mL/min; 柱温为30.0±5 ℃, 检测波长为361 nm。采用统计学方法分析不同产地荞麦的黄酮类成分差异。结果 各黄酮类化合物在浓度为0.5~50.0 mg/L的范围内线性关系良好(r>0.999),平均加标回收率为73.20%~114.90%, 相对标准偏差(relative standard deviations, RSD)为2.02%~6.81%; 精密度、稳定性、重复性实验的RSD值均小于5.35%, 6种黄酮化合物的检出限为0.07~0.14 mg/L, 定量限为0.23~0.45 mg/L。荞麦实际样品分析结果表明不同产地的荞麦中6种黄酮成分含量和总黄酮含量差异显著(P<0.05)。结论 该方法分析快速简便、稳定和重复性好, 可用于荞麦中芦丁、金丝桃苷、山奈酚-3-O-芸香糖苷、槲皮素、芹菜素和山奈酚6种黄酮成分含量的测定。为荞麦中黄酮的开发利用和含量的测定分析提供参考依据。     

雪松松针乙醇提取物的抗氧化活性及构效关系研究

研究雪松松针乙醇提取物的抗氧化活性及构效关系。通过体外化学分析法,测定雪松松针乙醇提取物的抗氧化活性;采用福林酚法和三氯化铝法,测定其总酚和总黄酮含量;利用高效液相色谱-质谱联用(HPLC-MS)与核磁共振(NMR)技术,鉴定其主要成分,并对其抗氧化作用的构效关系进行初步探讨。结果表明,雪松松针乙醇提取物对实验体系中的ABTS(EC₅₀:0.48±0.01 mg/mL)和DPPH(EC₅₀:32.40±0.76 μg/mL)自由基有很好的清除作用,能够高效地清除羟自由基(EC₅₀:1.73±0.01 mg/mL)和过氧化氢(EC₅₀:89.48±0.54 μg/mL)中的活性氧,抑制脂质过氧化(EC₅₀:9.85±0.14 mg/mL)并具有较高的还原能力,展现出显著的抗氧化活性;提取物拥有较高的总酚(40.30±2.13 mg没食子酸当量/g提取物)和总黄酮(56.62±1.53 mg芦丁当量/g提取物)含量;甲基松柏苷、阿魏酸-β-D-吡喃葡萄糖苷、荛花酚、断氧化马钱苷、(E)-1-O-对香豆酰-α-D-吡喃葡萄糖苷和天竺葵素-3-O-葡萄糖苷是松针乙醇提取物的主要成分,这些化合物结构中大量存在的具有氢原子转移或单电子转移能力的酚羟基、甲氧基、苄基等基团,是其展现良好抗氧化活性的重要原因。     

不同来源的苦荞茶中4种黄酮的含量测定

采用HPLC法同时测定不同来源的苦荞茶中芦丁、山柰酚-3-O-芸香糖苷、槲皮素和山柰酚四种成分含量,并比较差异。应用PLATISIL ODS(250 mm×4.6 mm,5μm)柱,流动相为甲醇-0.1%磷酸溶液,梯度洗脱,检测波长为355 nm,流速为1.0 m L/min,柱温为30℃。结果,不同来源的苦荞茶中,4种黄酮类成分含量差别很大。以果实制作的苦荞茶,芦丁、山柰酚-3-O-芸香糖苷的含量明显高于以皮层或全株制作的苦荞茶,而后者的槲皮素、山柰酚含量又明显高于前者。结果提示,以果实制作的苦荞茶含黄酮苷较多,更适宜冲饮。     

响应面法优化茵陈总黄酮提取工艺及成分结构的初步表征

本文优化了茵陈总黄酮的超声辅助提取工艺并对其成分结构表征进行了研究。在考察提取时间、提取温度、乙醇浓度、液料比对茵陈总黄酮得率影响的基础上,采用Box-Behnken响应面法对提取工艺进行优化,模拟得到二次多项式回归方程的预测模型。采用红外光谱(FT-IR)及液相色谱-质谱联用技术(LC-MS)鉴定了NKA-9树脂纯化后的茵陈黄酮类化合物。结果显示:响应面法优化得到茵陈总黄酮提取的最优工艺为提取温度61 ℃、乙醇浓度48%、液料比30:1 (mL/g),在此条件下,总黄酮得率可达24.89 mg/g。通过对比茵陈提取纯化物与芦丁标准品的FT-IR谱图,表明茵陈提取纯化物中含有C=C、羟基、酚羟基等多种特征官能团的振动吸收峰,是黄酮类化合物的典型结构,并可能含有芦丁单体。通过LC-MS分析茵陈黄酮提取物组成时,通过对比m/z值、保留时间,可推断提取物中含芦丁、金丝桃苷、异槲皮苷、异鼠李素-3-O-葡萄糖苷和香叶木苷等成分。响应面法建立的回归数据模型优化得到的茵陈总黄酮提取工艺实际有效,同时发现提取物中可能含有芦丁、金丝桃苷、异槲皮苷、异鼠李素-3-O-葡萄糖苷和香叶木苷等成分,以期为茵陈提取物的进一步研究提供参考。     

贵州蓝莓蜜的成分分析及其抗氧化活性

以贵州蓝莓蜜为研究对象,对其理化指标、抗氧化活性、多酚成分进行研究。结果显示,贵州蓝莓蜜酸度值44.69 mmol/kg,总糖含量79.30%,葡萄糖含量(40.88%)高于果糖含量(38.41%);总酚酸和总黄酮含量分别为20.27～24.72 mg GAE/100 g和3.88～6.77mg RE/100 g,DPPH和ABTS自由基半抑制率分别为119.04～136.56 mg/mL和140.56～212.34 mg/mL;蓝莓蜜含15种多酚类物质(原儿茶酸、对羟基苯甲酸、香草酸、咖啡酸、对香豆酸、芦丁、阿魏酸、杨梅酮、木犀草素、桑色素、槲皮素、芹菜素、山奈酚、异鼠李素、高良姜素),其中,黄酮类物质含量最高为槲皮素,酚酸含量由高到低为:对羟基苯甲酸对香豆酸阿魏酸咖啡酸香草酸原儿茶酸。研究表明,蓝莓蜜酸度偏高、易结晶,结合槲皮素含量高的特点与酚酸含量高低规律,可作为蓝莓蜜鉴定与检测的参考指标。     

优质稻米质量安全发展目标的研究

优质稻米生产实质是从田间到餐桌的全程质量安全控制管理问题。本文探讨了优质稻米全程质量安全发展意义、内容、模式和技术,为优质稻米质量安全全程控制提供科学决策依据。     

甘草精华素颗粒辅助调节血脂作用研究

目的:研究甘草精华素颗粒辅助调节血脂的作用。方法:40只Wistar大鼠,根据其体重及总胆固醇水平随机分为高、中、低3个剂量组及1个对照组。经口灌胃高脂饲料,同时剂量组饲以不同剂量的甘草精华素颗粒,对照组用蒸馏水代替。分别在第14天、第28天称重,并取尾血测定血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)等指标。结果:低、中剂量组的大鼠血清胆固醇浓度显著下降(p<0.01);低、中剂量组的大鼠血清甘油三酯浓度显著下降(p<0.01);各实验组大鼠血清高密度脂蛋白胆固醇浓度和对照组相比无统计学上的差异(p>0.05)。结论:甘草精华素颗粒可降低血清胆固醇和血清甘油三脂的水平,具有辅助调节血脂的作用。     

Total Antioxidant,Phenolic Compounds,and Total Oxidant Status of Certified and Uncertified Turkey's Honeys

In this study, total oxidant status (TOS), total antioxidant capacity (TAC), and total phenols (TP) of seventeen certified and eight uncertified honey samples were analyzed. The TAC and TOS of the samples were determined using novel methods. Uncertified honey samples had significantly lower values for their TP, TAC, and TOS contents than those of certified honey samples. There was significant correlation between TOS and TP values (P < 0.01) and between TOS and TAC values (P < 0.05).     

Physicochemical properties of high amylose rice starches purified from Korean cultivars

The physicochemical and pasting properties of high amylose rice starches isolated using alkaline steeping method from different Korean rice cultivars, Goamy2 and Goamy, and from imported Thai rice were examined. The protein and lipid contents of the Goamy2 starch were higher than those of the other two starches. The amylose and total dietary fiber contents were ranged from 31.4 to 36.8% and from 6.3 to 8.6%, respectively. Total dietary fiber was positively correlated to amylose content. Water binding capacity was higher in the Goamy2 starch (172.2%) than in the Goamy and Thai rice starches (112.7–115.6%). The swelling power of the Goamy2 starch showed lower values, but its value at 95°C was similar to others because of its rapid increment at 85°C. The granular size of Goamy2 starch was widely distributed compared to those of others. The Goamy2 starch showed a high initial pasting temperature (92.0°C) and low breakdown and setback viscosities. The Goamy and Thai rice starch granules were polygonal‐shaped with A‐type crystals, whereas the Goamy2 starch granules were round‐shaped with B‐type crystals. Goamy and Goamy2 starches showed a single endotherm at 60.8 and 76.0°C for peak temperature and 10.0 and 11.5 J/g for gelatinization enthalpies, respectively. The Thai rice starch presented an endotherm with a shoulder peak at 68.3°C (75.3°C for the main peak) and a gelatinization enthalpy of 12.4 J/g.     

蜜环菌菌丝与菌索活性成分含量研究

目的 测定蜜环菌(Armillaria mellea)菌丝、菌索两种形态总多糖、总蛋白、总三萜、麦角甾酮、麦角甾醇、腺苷的含量差异.方法 采用紫外-可见分光光度法测定总三萜、总多糖及总蛋白含量.采用高效液相色谱法测定麦角甾酮、麦角甾醇、腺苷成分含量.结果 蜜环菌菌丝与菌索两种形态的大部分活性成分含量差异显著,其中总三萜...     

卷烟常规化学成分与焦油的线性回归分析

对某种牌号卷烟的焦油量与其烟丝中的总糖、总氮和总氯的检测数据进行了回归分析,建立了根据烟丝中总糖、总氮和总氯的检测数据预测卷烟焦油量的线性回归方程,用得到的线性回归方程进行了预测,并将卷烟焦油预测值与实测值作了比较,结果表明,大部分数据的相对预测偏差都小于5%。     

Antioxidant power of Iranian propolis extract

Propolis is a resinous natural hive product derived from plant exudates collected by honey bees. Due to biological and pharmacological activities, it has been extensively used in folk medicine. The present study was designed to measure the antioxidant power of ethanolic extracts of propolis samples from different parts of Iran with “ferric reducing ability of plasma” (FRAP) assay and compare the results with Trolox at concentrations of 100, 1000 and 2000 μg/ml. FRAP values of propolis ethanolic extracts were in the range of 31.5 ± 14.6 to 1650 ± 72 μM, whereas the values of Trolox ranged from 125.25 ± 9.95 to 3381.64 ± 113.83 μM. The FRAP values of Tehran propolis ethanolic extract and Trolox at concentration of 100 μg/ml did not show any significant difference (P > 0.05). Total flavonoid and polyphenol contents of ethanolic extracts of propolis samples, determined by using aluminum nitrate and Folin–Ciocalteu colorimetric methods, were in the range of 1.22 ± 0.33–7.79 ± 0.39 g/100 g and 3.08 ± 0.02–8.46 ± 0.03 g/100 g crude extract of propolis, respectively. The result of this experiment may show that propolis as a natural source of antioxidant compounds may be of use in prevention of free radical-related diseases.     

不同品种杭白菊中酚类物质含量和清除自由基活性的比较

4种酮乡产杭白菊及黄菊和野菊,分别用乙醇-水体系进行热回流提取,用比色法测定醇提物中总酚和总黄酮含量,并用化学发光法检测春清除活性氧自由基的能力。结果表明,不同品种间含量存在较大差异,总酚和总黄酮含量（以菊花干基计）最高提异种大白菊,分别为9.76%和4.46%;最低的是黄山种野菊,分别为3.21%和1.99%。不同菊花均显示了良好的清除活性氧自由基的活性,清.OH和O2^.-的IC50分别在0.54-1.98mg/ml和24.2-54.5ug/ml之间,其中清O2^.-活性最强是大洋菊,最弱是软梗小洋菊;而清.OH能力最强为早小洋菊,最终为异种大白菊,结果表明,菊花中酚类物质的含量高低与抗自由基活性强弱无明显的对应关系。     

Dietary intake of pesticides: State of Kuwait total diet study

The State of Kuwait conducted a total diet study (TDS) to determine the dietary intakes of selected pesticides. This paper reports the results of this study. A national food consumption survey was performed and core food lists for different population groups were established representing the total diet of the Kuwaiti population. Food items (table-ready) were purchased/prepared and analysed for their contents of organophosphate/organochlorine carbamate, benzimidazole and phenylurea pesticides according to the US FDA Pesticide Analytical Manual (PAM I). Dietary intakes of these pesticides are presented for 19 population groups, which range from infants to elderly adults. The intakes of selected population groups are compared with representative findings from the US FDA/TDS and data published from other countries. In general, the average daily intakes were well below acceptable limits, but higher than those reported from developed countries.     

Nutritional value and antioxidant capacity of lunch meals consumed by elderly people of Sharpeville,South Africa

The main objective of this study was to determine the nutritional value and the total dietary antioxidant capacity (TDAC) of lunch meals consumed by elderly people attending a day-care centre in Sharpeville, South Africa. Meals were monitored and collected for a two-week period. The menus were analysed for water, ash, fat, protein, carbohydrates, polyphenols and antioxidant capacity. Eighteen food items, grouped in seven different menus, were identified. Energy provided by the menus covered 32% of the daily reference intakes for females and 25% for males, and the distribution of macronutrients in the menus was 10%, 34% and 56% for protein, fat and carbohydrates, respectively. This is close to the prescribed acceptable macronutrient distribution ranges of 10–35% protein, 20–35% fat and 45–65% carbohydrates. TDAC available from the menus was estimated at 332 μmol Trolox equivalents by DPPH (2,2′-diphenyl-1-picrylhydrazyl) and represented about 9% of the recommended daily allowance. Fruit, which represented only 2.8% of the amount of foods composing the menus, supplied 75.3% of TDAC, whilst contributions from vegetables and legumes were low. With 269 mg gallic acid equivalent in the menus, total phenolics appeared to be quantitatively the main dietary antioxidant, and were significantly correlated (r = 0.443 and p = 0.007) with antioxidant capacity. Fruit portions of the meals served by the day-care centre to the elderly of Sharpeville, need to be increased and diversified in order to reinforce their intake of antioxidants and thus reduce the incidence of non-communicable diseases.