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1.
为探究热带水果中植物甾醇的种类和含量。将香蕉、火龙果、木瓜、菠萝、龙眼样品进行冷冻干燥处理、索 氏抽提、皂化提取、衍生,采用气相色谱-质谱(GC-MS)法进行麦角甾醇、菜油甾烷醇、菜油甾醇、豆甾醇、谷甾醇的 分析测定,并用胆甾烷醇内标法进行定量分析。结果表明:菜油甾烷醇、麦角甾醇均为未检出。5 种甾醇的含量总和为 4.05~34.89 mg/100 g,含量顺序为火龙果>菠萝>木瓜>香蕉>龙眼。  相似文献   

2.
为探究热带水果中植物甾醇的种类和含量。将香蕉、火龙果、木瓜、菠萝、龙眼样品进行冷冻干燥处理、索氏抽提、皂化提取、衍生,采用气相色谱-质谱(GC-MS)法进行麦角甾醇、菜油甾烷醇、菜油甾醇、豆甾醇、谷甾醇的分析测定,并用胆甾烷醇内标法进行定量分析。结果表明:菜油甾烷醇、麦角甾醇均为未检出。5 种甾醇的含量总和为4.05~34.89 mg/100 g,含量顺序为火龙果>菠萝>木瓜>香蕉>龙眼。  相似文献   

3.
为了测定植物生长调节剂在香蕉中的残留,本研究建立了 QuEChERS 结合超高效液相色谱-串联质谱法同时测定香蕉中8种植物生长调节剂残留的分析方法。以1%乙酸-乙腈(V/V)为提取溶剂,样品前处理采用 QuEChERS 方法。以Agilent InfinityLab Poroshell 120 EC-C18柱为分离色谱柱,甲醇和5 mmol/L 乙酸铵-0.1%甲酸缓冲溶液为流动相,0.25 mL/min的流速梯度洗脱,10 min内可实现8种目标待测物分离。8种目标待测物经超高效液相色谱-串联质谱在选择反应监测模式下测定,基质匹配标准溶液外标法定量。结果表明,在5.0~100.0 μg/kg范围内线性良好,相关系数(r2)≥0.999;检出限(LODs)范围为0.03~0.6 μg/kg,定量限范围为0.10~2.0 μg/kg。在10、20、100 μg/kg 3个添加水平范围内,平均回收率在73.5%~107.2%之间,相对标准偏差(RSD)小于11%。本方法简便、快速、便捷、灵敏、准确,适用于香蕉中8种植物生长调节剂残留的测定。本方法的建立可为植物生长调节剂在其他果蔬中的残留检测提供参考。  相似文献   

4.
朱珠  吕岱竹  袁宏球 《热带作物学报》2013,34(12):2484-2488
构建戊唑醇在香蕉样品中的气相色谱-三重四级杆串联质谱残留检测方法。香蕉样品经乙腈提取,Strata Florisil(FL-PR)萃取小柱提纯净化,应用气相色谱-三重四级杆串联质谱测定,外标法进行定量分析。结果表明:戊唑醇在香蕉全果中的平均回收率为90.06%~91.28%,相对标准偏差为2.46%~2.69%;在香蕉果肉中的平均回收率为93.42%~102.85%,相对标准偏差为2.36%~3.33%。在香蕉全果检出限为0.001 mg/kg,果肉中检出限为0.001 2 mg/kg,该方法灵敏度高,重复稳定性好。结果准确可靠,符合国家相关规定,可用于香蕉样品中戊唑醇农药残留分析检测。  相似文献   

5.
采用高效液相色谱法(HPLC)对 4 种黔引迷迭香的多酚成分进行定性和定量分析,并利用 DPPH、ABTS自由基清除能力和铁离子还原能力(FRAP)3 种方法评价多酚成分的抗氧化能力。结果显示 4 种材料均富含类黄酮、酚酸和二萜酚等多酚类化合物,总酚含量介于 4 345.5~5 673.0 mg/100 g 。其中槲皮素、迷迭香酸、阿魏酸、绿原酸和鼠尾草酸是迷迭香最主要的酚类物质。黔引迷迭香 4 号的抗氧化活性最高,利用 DPPH、ABTS 和 FRAP等 3 种方法检测的结果依次为 184.4、290.0、155.6 μmol/g。相关性分析表明,总酚与总抗氧化活性能力显著相关,迷迭香酸对总抗氧化活性能力贡献最大,其次为鼠尾草酸、槲皮素和水杨酸。本研究对于了解黔引迷迭香抗氧化活性成分,以及资源的进一步开发利用具有重要指导意义。  相似文献   

6.
采用超高效液相色谱—串联质谱,研究了多菌灵、吡虫啉和啶虫脒在毛叶枣中的消解动态和最终残留量。毛叶枣样品经乙腈提取,低温冷冻液萃取后,采用正离子多反应监测模式(MRM)测定,结果表明:在 0.1~10 μg/L范围内,3 种农药的线性关系良好,检出限为 0.06 μg/kg,定量限为 0.20 μg/kg,回收率范围为 89.1%~97.0%,相对标准偏差为 5.3%~6.9%。田间试验结果表明,多菌灵、吡虫啉和啶虫脒在毛叶枣中的消解半衰期分别为 3.2、3.3、2.8 d,最终残留试验结果表明,在毛叶枣采收期时 3 种农药均有低含量检出,表明 3 种农药在毛叶枣上的残留时期较长,喷施时需控制好喷施浓度和间隔期。  相似文献   

7.
奇楠沉香中2-(2-苯乙基)色酮的GC-MS分析鉴定   总被引:1,自引:0,他引:1  
采用乙醚浸提法提取奇楠沉香样品,并应用气相色谱-质谱联用(GC-MS)技术分析测定其中的化学成分及相对含量,鉴定了11个化合物。同时采用柱色谱技术对该乙醚提取物进行分离纯化得到单体化合物1~6,其结构通过核磁共振等波谱技术鉴定为2-(2-苯乙基)色酮类化合物。通过质谱比对,将GC-MS分析中未能鉴定的5个含量较高的成分分别鉴定为化合物2~6。样品中2-(2-苯乙基)色酮类化合物的相对含量达到63.62%,表明奇楠沉香富含2-(2-苯乙基)色酮类化合物。探讨了2-(2-苯乙基)色酮类化合物的质谱裂解规律,有  相似文献   

8.
采用气相色谱/质谱(GC/MS)联用技术,分别对新鲜香蕉、真空微波干燥、联合热风干燥后的香蕉片香气挥发性成分进行检测,结果表明:不同干燥方式的香蕉片样品主成分分析中所含香气成分都分布在不同象限,有不同的差异,且保留乙酸异戊酯、丁酸异丁酯、丁酸丁酯等与香蕉的特征风味相关的香气挥发性成分。另样品中所含香气成份对热不稳定,易降解或其它热反应,同时也会生成一系列具有各自独特风味的香气成分。经真空微波干燥处理样品具丁子香酚甲醚、榄香素等香气成分,而联合热风干燥样品具不同香型的烯类、酮类化合物。  相似文献   

9.
为了了解一种国外沉香中的2-(2-苯乙基)色酮类化合物,采用多种色谱分离技术从该沉香的乙醇提取物中分离得到6个化合物,通过波谱学方法分别鉴定为:6-羟基-8-氯-2-[2-(4°-羟基苯基)乙基]色酮(1),6-羟基-2-[2-(3°-甲氧基-4°-羟基苯基)乙基]色酮(2),6-羟基-7-甲氧基-2-[2-(4°-羟基苯基)乙基]色酮(3),沉香四醇(4),5α,6β,7β,8α-四羟基-2-[2-(4°-甲氧基苯基)乙基]-5,6,7,8-四氢色酮(5)和6-羟基-2-[2-(3°-甲氧基-4°-羟基苯基)乙烯基]色酮(6)。化合物1为新的2-(2-苯乙基)色酮。对化合物2~6的细胞毒活性测试结果表明,化合物6对5株人体肿瘤细胞均表现出一定活性,其中对人慢性髓原白血病细胞K562和人肝癌细胞BEL-7402具有显著抑制活性,半数抑制浓度(IC50)为2.87和 4.75 μg/mL,化合物2、3、5对5株人体肿瘤细胞表现出中等活性,IC50范围为9.91~45.38 μg/mL。  相似文献   

10.
气质联用方法测定香蕉根系分泌物   总被引:3,自引:0,他引:3  
采用砂培试验,通过离位溶液培养法收集香蕉根系分泌物,分别测定收集原液中可溶性总糖、蛋白质和总酚酸的含量,用气相色谱-质谱联用技术测定了提取物成份。结果表明,与对照(灭菌生物有机肥)比较,生物有机肥处理的根系分泌物中可溶性总糖和总酚酸的含量显著降低;在接种病原菌情况下施用生物有机肥处理仍能显著降低两种物质含量。不同处理的香蕉根系分泌物中都含有烃类、萜类、醇类、酸类、酯类和醛类化合物;3种处理检测到的根系分泌物种类分别为41、30和32种。  相似文献   

11.
The contents of total phenolic compounds, flavonoids, and phenolic acids were determined in selected garlic cultivars grown at four locations. The total phenolic content varied from 3.4 mg gallic acid equivalents (GAE)/g of dry matter (dm) to 10.8 mg GAE/g of dm with a mean value of 6.5 mg GAE/g of dm. The myricetin, quercetin, kaempferol, and apigenin flavonoids were not detected in any of the samples. Caffeic acid and ferulic acid were the major phenolic acids found with mean values of 2.9 mg/kg of dm and 2.6 mg/kg of dm, respectively. The mean contents of vanillic, p-hydroxybenzoic, and p-coumaric acids were comparable (0.4–0.8 mg/kg of dm), and the level of sinapic acid was negligible (< 0.1 mg/kg of dm). There was a significant effect of location but an insignificant effect of genotype on contents of caffeic, vanillic, p-hydroxybenzoic, and p-coumaric acids. However, genotype but not location affected the contents of total phenolics and ferulic acid. On average, the white garlic cultivars and Chinese garlic cultivars contained higher contents of total phenolics and ferulic acid than the purple garlic cultivars. However, the differences in the total phenolic content between the purple and white garlic cultivars were not significant.  相似文献   

12.
Rice production generates a significant amount of agricultural waste. This study aimed to give results related to the existence of antioxidant phenols in agricultural waste of selected Northern Thai rice varieties. The antioxidant activities, contents of total flavonoids and phenolic compounds in the ethanolic rice husk extract were evaluated. The highest antioxidant activities were found in the variety PES1CMU, with 2,2?-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid and 2,2-diphenyl-1-picrylhydrazyl as 679.66 and 4.16 mmol/(L·g) trolox equivalent, respectively, ferric reducing antioxidant power as 0.87 mmol/(L·g) Fe2+, total phenolic content as 29.90 mmol/(L·g) gallic acid and total flavonoid content as 12.16 mg/g catechin equivalent. Polyphenol compounds were identified mainly by standard polyphenols using the liquid chromatography mass spectrometry, with the highest contents of phytic acid, o-coumaric acid, naringin and kaempferol. The non-glutenous and wetland ecotypes of rice husk samples were the richest in antioxidant activities and polyphenol contents characterized by using principal component analysis. The glutenous rice husk contained higher antioxidant activities than the rest. Interestingly, quercetin is a significant phenolic compound that positively correlated with the overall antioxidant activities of rice husk. This finding will be relevant for future application of rice husk antioxidant components in the production of functional ingredients as well as for the food and pharmaceutical industries.  相似文献   

13.
Vigna aconitifolia sprouts (Moth bean sprouts, MBS) were analyzed for their nutritional and antioxidant properties during sprouting. Sprouting for six days led to a 7.0 fold increase in fresh weight, 2.4 fold increase in soluble proteins, 3.0 fold increase in carbohydrates, and a 5.5 fold increase in mineral content. Phenolic content also increased by 28% during germination. Caffeic acid, ferulic acid, cinnamic acid and kaempferol were the predominant phenolic compounds detected in the ethanolic extracts of MBS by HPLC. Following supplementation with metal ions (200 μg ml?1), the sprouts demonstrated a considerable increase in metal ion uptake, with improved phenolic content. MBS ethanolic extracts also reduced intracellular oxidative stress in HepG2 cells.  相似文献   

14.
基于UPLC-Q-TOF-MS技术对益智种子和果皮乙醇提取物的非挥发性成分进行分析。采用回流提取法制备供试样品,采用超高效液相色谱仪分离益智种子和果皮乙醇提取物化学成分,以Waters ACQUITY UPLC HSS T3(100 mm× 2.1 mm,1.8 μm)色谱柱为分析柱,0.1%甲酸水溶液-0.01%甲酸乙腈溶液为流动相进行梯度洗脱,流速0.3 mL/min,质谱采用电喷雾离子源(ESI),四极杆-飞行时间质谱采集其一级和二级高分辨质谱数据,并用Masslynx软件对原始质谱数据进行分子特征提取,结合文献报道信息,综合分子相应结构特征、精确相对分子质量和质谱裂解规律,对化合物结构进行识别鉴定。从益智种子和果皮乙醇提取物中分别鉴定32个和50个非挥发性成分,包括黄酮类、酚酸类、糖类、脂肪酸类和萜类化合物等5类成分,其中有58个化合物为首次从益智中分离得到;益智种子的主要成分为酚酸类(11个)化合物,也是益智种子的代表性成分,占总鉴定结构化合物总数的三分之一,而益智果皮中的酚酸类成分较少,仅鉴定得到6个酚酸类化合物;益智果皮主要成分为黄酮类(19个)化合物,占总鉴定结构的化合物总数近三分之一,且种类丰富,而种子中仅鉴定得到1个黄酮类化合物;二者中共有成分仅4个,分别是单糖类化合物D-gluconic acid、D-glucopyranuronic acid,二糖类化合物sucrose和黄酮类化合物chysin。结果表明,益智种子非挥发性化学物质较少,而益智果皮中含有的化学物质种类较多;益智种子和果皮的化学成分差异较大:益智种子主要成分为酚酸类活性物质,益智果皮则以黄酮和萜类成分为主,在综合利用和质量控制上应区别对待使用。  相似文献   

15.
Three hydroxybenzoic acids: p-hydroxybenzoic acid, vanillic acid and syringic acid; six hydroxycinnamic acids: p-coumaric acid, ferulic acid and four ferulic acid derivatives and a flavonoid (apigenin) were identified and quantified in 34 accessions corresponding to 19 cultivars of wheat applying HPLC coupled to diode array detector. Considerable differences between the wheat cultivars were observed in the phenolic contents. Some cultivars (Colorado, Del País, Barbilla, Jallado, Raspinegro Canario and Plaganudo) could be selected according to the high levels of phenolic compounds. Ferulic acid was the major phenolic acid compound followed by syringic and p-hydroxybenzoic acids. The proportion of ferulic acid present as dimeric forms ranged from 4.2 to 8.6% across all of the wheat cultivars analyzed. Apigenin, p-hydroxybenzoic and syringic acids did not show significant correlations. Many correlations between the determined hydroxycinnamic acids were observed. The ferulic acid and all the ferulic acid derivatives showed highly significant correlations, suggesting that the concentrations of diferulic acids depend on the concentration of ferulic acid.  相似文献   

16.
In this report, we presented the profile of polyphenolic substances in flowers, leaves, stalk and roots of Fagopyrum tataricum estimated by using RP–UHPLC–ESI-MS equipment (reversed-phase ultra-high-performance liquid chromatography electrospray ionisation mass spectrometry). The neutral detergent fibre, acid detergent fibre, acid detergent lignin, cellulose and hemicellulose were also determined. Flowers, leaves, stalk and roots showed varying levels of dietary fibre and polyphenols. The highest content of neutral and acid detergent fibre were found in the roots (63.92 and 45.45% d.m., respectively) while the most rich in phenolic compounds were flowers (4.8 mg/1 g d.m.). Root and stalk contained the highest level of cellulose, 38.70 and 25.57% d.m., respectively. Among the investigated polyphenolic substances such as: 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-hydrobenzoic acid, caffeic acid, catechin, chlorogenic acid, fagopyrin, ferulic acid, myricetin, gallic acid, isovanilic acid, isovitexin, kaempferol, luteolin, p-coumaric acid, procyanidin B2, quercetin, quercetin 3-D galactoside, rutin, syringic acid and vitexin, we observed that the contents of rutin and chlorogenic acid were the highest. We found some correlation between dietary fibre fractions and individual phenolic substances. The levels of acid detergent fibre (ADF), cellulose and hemicellulose were negatively correlated with isovitexin, kaempferol, vitexin, fagopyrin, caffeic acid and procyanidin B2 content. In this investigation, two solvents (water and methanol) were estimated regarding their extraction efficiency of phenolic compounds. Taking these results into consideration, we recommend using methanol as the extractor to isolate chlorogenic acid, fagopyrin, kaempferol, procyanidin B2, quercetin, quercetin 3-D-galactoside, rutin, vitexin, and water for other investigated polyphenolic substances obtained from Fagopyrum tataricum.  相似文献   

17.
Chickpea (Cicer arietinum L.) genotypes, nine kabuli from Mexico and 9 desi from other countries, were investigated for their phenolic profiles and antioxidant activity (AA). Phenolics in methanol extracts (ME) were analyzed by ultra-performance liquid chromatography coupled to diode array detection and mass spectrometry (UPLC-DAD-MS), whereas the AA was measured as Trolox equivalents (TE) by ABTS, DPPH and FRAP methods. Twenty phenolic compounds were identified in the ME and their levels showed a great variability among the chickpea genotypes. Phenolic acids and flavonoids were the most abundant compounds in kabuli and desi genotypes, respectively. The AA values (μmol TE/ 100 g dw) by ABTS (278–2417), DPPH (52–1650), and FRAP (41–1181) were mainly associated with the content of sinapic acid hexoside, gallic acid, myricetin, quercetin, catechin, and isorhamnetin, suggesting they are the main compounds responsible for the AA. The sum of the AA obtained for standards of these compounds evaluated at the concentration found in the extracts accounted for 34.3, 69.8, and 47.0% of the AA in the extract by ABTS, DPPH, and FRAP, respectively. In the AA by DPPH, most of the mixtures of these compounds resulted in synergistic interactions. Three desi genotypes with black seeds (ICC 4418, ICC 6306, and ICC 3761) showed the highest AA and flavonoids content, whereas the most promising kabuli genotypes were Surutato 77, Bco. Sin. 92, and Blanoro that showed the highest values of phenolic acids. These genotypes represent good sources of antioxidants for the improvement of nutraceutical properties in chickpea.  相似文献   

18.
Low molecular weight phenolic compounds present in heat processed oats (Avena sativaL) were analysed. The oat grains were of three varieties (Kapp, Mustang and Svea), stored at different relative humidities (30, 55 or 80%) and periods (3·5 or 15·5 months) and processed with or without hulls. Eleven UV-absorbing compounds detected by High Performance Liquid Chromatography were subjected to univariate and multivariate statistical analysis. The selected compounds included caffeic acid,p-coumaric acid, ferulic acid, vanillic acid,p-hydroxybenzaldehyde, vanillin, coniferyl alcohol, three avenanthramides and one unidentified substance. The levels of vanillic acid, vanillin and, especially,p-coumaric acid,p-hydroxybenzaldehyde and coniferyl alcohol increased significantly in samples processed with hulls, but not in samples processed without hulls. Ferulic acid increased in both processes, while caffeic acid and the avenanthramides were found to decrease during processing. Storage of unprocessed samples for 1 year generally increased the levels of phenolic acids and aldehydes. For the phenolic acids (except ferulic acid), this increase was most pronounced after storage at high relative humidity (80%). The avenanthramides were present at their highest levels in Mustang, caffeic acid in Svea and Mustang, the unidentified compound in Svea, while all the other compounds studied were present predominantly in the variety Kapp.  相似文献   

19.
Summary The phenolic acids benzoic, caffeic, chlorogenic, ferulic, p-coumaric, protocatechuic, salicylic, sinapic, syringic and vanillic together with vanillin, were tested for their ability to inhibit polygalacturonic acid lyase (PL) and polygalacturonase (PG) in culture filtrates ofErwinia carotovora subsp.carotovora. None of the compounds inhibited PL at 200 μg/ml, although syringic and sinapic acids caused a 54% and 43% reduction respectively at 400 μg/ml. PG was strongly inhibited by caffeic acid (57% inhibition at 100 μg/ml) and chlorogenic acid caused slight inhibition. Little if any inhibition of PG was caused by benzoic, ferulic, p-coumaric, protocatechuic, salicylic, sinapic, syringic, and vanillic acids or vanillin. The percentage inhibition of PG by chlorogenic acid was not affected by pH values over the range 4–7.  相似文献   

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