采用高效液相色谱串联质谱法分析黑粒小麦麸皮中的花色苷组成

以黒粒小麦麸皮为原料,应用高效液相色谱配以串联质谱和二极管阵列检测技术对黒粒小麦中麸皮中的花色苷的组成进行了分析。结果显示:从黒粒小麦麸皮中分离鉴定出9种不同的花色苷类化合物———矢车菊素-己糖苷、矢车菊素-芦丁苷、芍药素-己糖苷、矢车菊素-丙二酰葡萄糖苷、飞燕草素-己糖苷、飞燕草色素-芦丁苷、锦葵色素-芦丁苷、芍药素-芦丁苷及牵牛花素-芦丁苷,其中飞燕草类花色苷和矢车菊素类花色苷是主要花色苷,分别占全部花色苷含量的50.27%和30.04%。     

七种花色苷色素中矢车菊-3-葡萄糖苷含量研究

目的:调查研究七种花色苷色素中矢车菊-3-葡萄糖苷的含量.方法:实验采用高效液相色谱法,检测条件为Ultimate(R)LP-C18(5μm,250mm ×4.6mm)色谱柱;甲酸水溶液(1∶9)∶甲醇=85∶15(v/v)梯度洗脱;流速1mL/min;柱温30℃;检测波长535nm.结果:萝卜红、甘薯红、甜菜红中不含矢车菊-3-葡萄糖苷,葡萄皮色素、欧洲越橘色素、红米红、甘蓝红中矢车菊-3-葡萄糖苷含量分别为5.09％、4.15％、10.84％、0.03％.结论:七种花色苷色素中矢车菊-3-葡萄糖苷含量存在明显差异,葡萄皮色素、欧洲越橘红色素、红米红中矢车菊-3-葡萄糖苷含量较高,为矢车菊-3-葡萄糖苷的进一步开发利用提供了可靠的理论依据.     

结球红菊苣(Cichoricum intybus var.foliosum Hegi.)花色苷初步研究

采用pH示差法测定结球红菊苣中花色苷的含量,并采用高效液相色谱-光电二极管阵列检测器-离子阱/飞行时间质谱(HPLC-DAD-IT/TOFMS)技术对结球红菊苣花色苷溶液进行了检测和鉴定。结球红菊苣花色苷溶液是从结球红菊苣中用0.1%盐酸-甲醇溶液提取,并经C18固相萃取小柱纯化制备而成。结果表明,结球红菊苣中花色苷含量为37.3±12.25mg/100gFW,主要由四种矢车菊花色素的糖苷衍生物组成,分别是矢车菊-3-O-葡萄糖苷、矢车菊-3-丙二酰半乳糖苷、矢车菊-3-丙二酰葡萄糖苷、矢车菊-3-琥珀酰葡萄糖苷,其中矢车菊-3-丙二酰葡萄糖苷含量最高,占结球红菊苣叶子中花色苷总量的82.01%。     

HPLC-ESI-MS分析紫色小白菜中花色苷组成分析

采用HPLC-ESI-MS方法测定并分析"新紫冠"紫色小白菜中花色苷的组分及其含量。结果表明,"新紫冠"紫色小白菜中含有矢车菊及飞燕草两类花色苷,以矢车菊-3,5-双葡萄糖苷标准品测得总花色苷含量为51.36μg/g·fw,其中矢车菊类花色苷含50.71μg/g·fw,占总含量的98.73%,飞燕草类花色苷含0.65μg/g·fw,仅占1.27%。矢车菊类花色苷全部以酰基化的形式存在,共检测出10种矢车菊类花色苷及相应的9种同分异构体,其中矢车菊-3-阿魏酰-槐糖苷-5-丙二酰-葡萄糖苷是含量最多的花色苷成分,达16.36μg/g·fw,占总含量的31.85%。     

黑豆皮花色苷的中压液相色谱制备及结构鉴定

以黑豆皮为实验材料,用乙醇浸提法对黑豆皮中的花色苷进行提取,用大孔吸附树脂对花色苷进行纯化,经冷冻干燥得到黑豆皮花色苷粗品。利用中压制备色谱对花色苷组分进行分离,通过质谱分析鉴定经中压制备色谱分离后的花色苷组分。结果表明:黑豆皮花色苷粗品中的总花色苷含量为26.9%,经中压制备色谱对花色苷粗品进行分离后的2峰中矢车菊素-3-葡萄糖苷纯度达到91.46%。黑豆皮中的主要花色苷为天竺葵素-3-O-芸香糖苷、芍药色素-3-O-葡萄糖苷、矢车菊素-3-O-葡萄糖苷和锦葵素-3-葡萄糖苷-4-乙醛。     

欧李花色苷的分离及其鉴定

采用高效液相色谱与离子阱串联飞行时间检测器-质谱联用技术,分离鉴定欧李中的花色苷类化合物。结果表明：从欧李红色素中分离得到6种组分,分别为：矢车菊-3-葡萄糖苷、天竺葵-3-葡萄糖苷、矢车菊-3-鼠李糖葡萄糖苷、天竺葵-3-鼠李糖葡萄糖苷、矢车菊-3-乙酰基葡萄糖苷、天竺葵-3-乙酰基葡萄糖苷。其中,矢车菊-3-葡萄糖苷为主要花色苷,占欧李总花色苷含量的62.6%。因此,采用高效液相色谱-质谱联用技术可有效地分离分析欧李中花色苷类物质。     

UPLC-Q-Tof/MS同时测定桑葚保健酒中五种花色苷含量

目的:建立超高效液相色谱-四级杆-飞行时间质谱(UPLC-Q-Tof/MS)法测定桑葚保健酒中五种花色苷(天竺葵-3-O葡萄糖苷、氯化芍药素-3-O-葡萄糖苷、矢车菊-3-O芸香葡萄糖苷、锦葵色素-3-5-二葡萄糖苷、矢车菊-3-O葡萄糖)含量。方法:色谱柱:ACQUITY UPLC Ben C18 Column (2.1mm×100mm,1.7μm),流动相为乙腈-0.1%甲酸,进样量为2μL,流速为0.5mL/min,梯度洗脱,柱温为40℃,ESI+电离模式。结果:五种花色苷在100～800ng/mL范围内线性关系、回收率良好。桑葚保健酒中矢车菊-3-O-芸香葡萄糖苷、矢车菊-3-O-葡萄糖苷含量丰富,达到398.0ng/mL以及532.8ng/mL。     

云南丽江和吉林靖宇11种越橘果实花色苷组分的分析

采用高效液相色谱法对云南丽江、吉林靖宇11种越橘果实花色苷组分进行测定。通过标准品的分析,建立了飞燕草素-3-半乳糖苷、飞燕草素-3-葡萄糖苷、矢车菊素-3-半乳糖苷、矢车菊素-3-葡萄糖苷、锦葵色素-3-半乳糖苷、锦葵色素-3-葡萄糖苷的回归方程,相关系数为0.9939~0.9968,精密度RSD为2.00%~3.73%,回收率在98.90%~100.99%,方法准确可行。通过6种标准品的对比,供试的15个样品中,所有越橘品种均有飞燕草素-3-半乳糖苷、矢车菊素-3-半乳糖苷、锦葵色素-3-半乳糖苷3种花色苷,飞燕草素-3-半乳糖苷平均含量为223.99 μg/g、锦葵色素-3-半乳糖苷平均含量为153.34 μg/g,二者占总花色苷的65%。采用欧氏距离聚类分析表明,集群1为飞燕草素-3-半乳糖苷含量较高的三种越橘,代表品种为丽江雷戈西、丽江奥尼尔、靖宇杜克;集群2为6种花色苷总含量较高的越橘品种,代表品种为丽江北陆与靖宇早蓝,说明飞燕草素-3-半乳糖苷含量与花色苷总含量是评价越橘花色苷特点的重要因子。     

不同大豆种质种皮黄酮类色素的差异分析

为探究大豆种皮中黄酮类色素的含量和分布规律,选取167份大豆种质资源为实验材料,利用高效液相色谱(HPLC)法对大豆种皮黄酮类色素含量进行测定。结果表明：大豆种皮花色苷组分中矢车菊素-3-O-葡萄糖苷含量最多,异黄酮组分中大豆苷含量最高。花色苷组分在野生和半野生大豆种皮中高于栽培大豆。异黄酮组分中染料木苷在野生大豆中最高,黄豆黄苷在半野生大豆中最高,其他组分在栽培大豆中最高。栽培大豆黑色种皮花色苷组分、染料木苷和大豆苷元含量最高,青色种皮大豆苷和黄豆黄苷含量最高,双色种皮黄豆黄素含量最高。相关分析表明3类结合型糖苷内部、3类游离型苷元内部、3种花色苷组分内部两两相关极显著。大豆苷与游离型苷元、矢车菊素-3-O-葡萄糖苷相关显著。聚类分析将大豆材料划分为三大类群,第一类群除黄豆黄苷和飞燕草素-3-O-葡萄糖苷外,其他色素组分含量均最高,为黄酮类色素的研究和利用提供参考。     

不同种植地区蓝莓果中花色苷的分布

目的:探究不同种植地区的蓝莓果实中花色苷含量与海拔高度、纬度等环境因素之间的关系。方法:选取不同海拔高度和纬度的10个种植地区“灿烂”品种的兔眼蓝莓果实为研究对象,采用高效液相色谱法(HPLC)和高效液相色谱-电喷雾质谱(HPLC-ESI-MS)定性和定量分析蓝莓果中花色苷的组成成分,比较不同种植地区的蓝莓果中花色苷苷元、糖基组成与含量的差异。结果:从蓝莓果中检测到5类花青素苷元,共13种花色苷,苷元含量组成由高到低为锦葵色素>矢车菊素>飞燕草素>矮牵牛素>芍药素;糖基组成由高到低为半乳糖苷>阿拉伯糖苷>葡萄糖苷,其中从芍药素中仅检测到半乳糖苷。蓝莓果中锦葵色素-3-O-半乳糖苷和矢车菊素-3-O-半乳糖苷的含量最高,而飞燕草素-3-O-葡萄糖苷和矮牵牛素-3-O-葡萄糖苷含量低,在部分地区的蓝莓果中缺失或未检测到。不同种植地区蓝莓果中花色苷组成虽基本一致但含量存在差异。云南龙朋代表的低纬度、高海拔地区种植的蓝莓果中花色苷总含量最高,高纬度、低海拔地区的浙江草塔的蓝莓果中花色苷总含量最低。结论:不同种植地区的地理环境影响蓝莓果中花色苷的分布,高海拔地区的环境条件更利于蓝莓果实中花色苷的合成和积累。     

Phenolic composition and inhibitory effect against oxidative DNA damage of cooked cowpeas as affected by simulated in vitro gastrointestinal digestion

Cowpeas contain phenolic compounds with potential health benefits. The effect of simulated gastrointestinal digestion on phenolic composition of cooked cowpeas and the ability of the digests to inhibit radical-induced DNA damage was determined. A red and a cream-coloured cowpea type were used. The phenolic composition of acetone extracts and enzyme digests of cooked cowpeas was determined using UPLC-MS. Compounds such as p-hydroxybenzoic acid, p-coumaric acid, coumaroylaldaric acid and feruloylaldaric acid were present in the acetone extracts of the cooked cowpeas but were not detected in the enzyme digests. Glycosides of quercetin and myricetin decreased upon in vitro gastrointestinal digestion of cooked cowpeas whereas flavan-3-ols were hardly present except catechin glucoside. The enzyme digest of the red cowpea type was about thrice as effective as that of the cream cowpea type in protecting DNA from oxidative damage. The observation that enzyme digests of cooked cowpeas inhibited radical-induced DNA damage suggests that cowpea phenolics retain some radical scavenging activity after gastrointestinal digestion.     

Evaluation of extracts of neem (Azadirachta indica A. Juss) for the control of some stored product pests

Laboratory investigations on the activity of neem leaf and seed extracts in water or methylated spirit on Callosobruchus maculatus, Sitophilus oryzae and Cylas puncticollis were made at 27 ± 2°C and 65 ± 5% r.h.. Field trials were conducted to determine their effectiveness as protectants of cowpeas and maize in storage at 28 ± 4°C and 82 ± 7% r.h for 5 months.

The results showed that the effectiveness of neem is affected by differences in insect behaviour. The extracts were more active as suppressants of C. maculatus than Sitophilus spp; there was no effect on C. puncticollis. All of the extracts tested resulted in a significant reduction in oviposition, % egg hatch and % adult emergence in C. maculatus and in adult emergence of Sitophilus.

Field trials showed that the extracts mostly gave good protection to cowpea against C. maculatus for 5 months, but only moderate protection to maize against S. zeamais. Seed extracts were more effective than leaf extracts.     

不同发酵方式对酸豆角品质和风味的影响

为了提高酸豆角的品质,本研究以新鲜豆角为原料,采用自然湿法发酵和纯种湿法发酵腌制酸豆角。通过对不同方法腌制过程中pH、总酸、氨基酸态氮、还原糖和总糖及亚硝酸盐含量进行测定,并对发酵后酸豆角进行质构分析,探究自然湿法发酵和纯种（植物乳杆菌接种量为0.04 g/kg）湿法发酵对酸豆角品质的影响;结合感官评分和气相色谱-质谱联用（GC-MS）对发酵后酸豆角的风味成分进行解析。结果表明:发酵过程中,纯种湿法发酵酸豆角中pH、总酸、氨基酸态氮和亚硝酸盐含量均低于自然湿法发酵;还原糖和总糖含量的消耗速率高于自然湿法发酵。发酵后,纯种湿法发酵酸豆角的硬度、脆度及感官评分均优于自然湿法发酵。两种方式腌制的酸豆角中挥发性风味物质较为相近,且酯类、酸类和醇类物质含量较高。与自然湿法发酵相比,纯种湿法发酵酸豆角缩短了发酵周期,降低了亚硝酸含量且最低含量为0.035 mg/kg,保持了与自然发酵酸豆角相近的风味,该研究为酸豆角的品质优化和风味成分解析提供一定参考价值。     

Micronisation and hot air roasting of cowpeas as pretreatments to control the development of hard-to-cook phenomenon

BACKGROUND: Cowpeas stored under conditions of high temperature and high relative humidity (HTHH) develop the hard‐to‐cook (HTC) defect. Cowpeas with HTC defect require long cooking times, limiting their utilisation. Heat pretreatments are aimed at inactivating the enzymes responsible for HTC defect development. In this study, two heat pretreatments, micronisation and hot air roasting, were evaluated to assess their effectiveness in controlling the HTC defect development in cowpeas after storage under HTHH conditions. RESULTS: Micronisation and hot air roasting as pretreatments reduced the cooking time of cowpeas after storage under HTHH conditions compared with the control. The differences in the effectiveness of HTC defect control between micronisation and roasting were dependent on the degree of phytase inactivation on day 0. Phytase activity was reduced by 45 and 70% by roasting and micronisation pretreatments respectively. Reduced phytase activity was associated with higher phytate and soluble pectin contents in micronised cowpeas than in roasted cowpeas after HTHH storage. This observation is in agreement with the phytase‐phytate‐pectin theory. CONCLUSION: Micronisation was more effective than hot air roasting in controlling the development of HTC defect. This was due to a higher degree of phytase inactivation in micronisation when compared with roasting. Copyright © 2011 Society of Chemical Industry     

The efficacy of harvest time modification and intercropping as methods of reducing the field infestation of cowpeas by storage bruchids in Kenya

A study was carried out in Eastern Province, Kenya to evaluate whether the harvesting of cowpeas at different times and intercropping with maize were effective in reducing field infestation by storage bruchids.

Cowpea seed harvested very late (4 weeks after the recommended harvest time) was infested by storage bruchids to a significantly greater extent than cowpeas harvested early or at the recommended harvest time. The intercropping experiments showed that bruchid infestation was significantly reduced in the intercropped cowpeas. These results are discussed in view of the current cowpea farming systems in Kenya.     

The effectiveness of six vegetable oils as protectants of cowpeas and bambara groundnuts against infestation by Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

Traditionally extracted neem kernel oil, karité oil, groundnut oil, palm kernel oil, palm oil and industrially extracted groundnut oil were assessed as protectants of cowpeas and bambara groundnuts against Callosobruchus maculatus (F.). On cowpea, only neem kernel oil reduced oviposition at a treatment of 8 ml oil/kg seed. On bambara groundnut, neem kernel oil, palm oil and groundnut oil (industrially extracted) reduced oviposition at 3 ml oil/kg seed, while karité oil was effective at 5 ml oil/kg seed. With oil treatment, the degree of ovicidal activity was higher on bambara groundnuts than on cowpeas. Only neem oil also showed larvicidal properties. Even after 90 days storage, a major part of the toxic activity was retained by the cowpea testa. Neem oil at 8 ml oil/kg cowpea seed gave good protection up to 3 months, while 5 ml oil/kg bambara groundnut protected up to 6 months.     

Physico-chemical and nutritional properties of cowpeas (Vigna unguiculata) heated under pressure

Cowpeas (Vigna unguiculata (L) Walp) at four stages of maturity were heated in water at 34.5 kPa for varying times up to 40 min. All measurements except ash were affected by the stage of maturity and time of heating. Changes occurred most rapidly during the first 10 min of heating. The greenness of the most immature cowpeas was lost. The degrees of firmness of all groups differed initially but decreased rapidly during the first 5 min and more slowly thereafter. Fresh cowpeas were softened sufficiently for eating after 10 min at which time pH increased 0.65 units to pH 6.75 and acidity decreased to 0.17%. In-vitro protein digestibility of the most mature, unheated cowpeas was 70.7% and increased to 83.4% after 10 min heating. Heating decreased the original trypsin inhibitor activity by 81.7% after 5 min and 85.9% after 10 min.     

Cowpea Flour Vitamins and Trypsin Inhibitor Affected by Treatment and Fermentation with Rhizopus microsporus

Soaking cowpeas (25°C, 24 hr) decreased folacin content but did not affect thiamin, niacin, and riboflavin. Boiling soaked seeds for 45 min sharply decreased thiamin, folacin, niacin, and riboflavin. Losses of folacin, niacin, and riboflavin were recovered during fermentation. Soaking reduced trypsin inhibitor activity (TIA) by ～20%, whereas boiling of soaked seeds decreased TIA by ～85%. A slight increase in TIA occurred in soaked, cooked cowpeas after 18 hr fermentation.     

Egg production and development of three strains of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

The numbers of eggs laid by individual females of three geographically isolated strains of C. maculatus (F.) on different numbers of cowpeas were counted. Females of strains originating in the Yemen and Brazil laid about 40 eggs when provided with a single cowpea, whilst females of a Nigerian strain laid 75. Given 40 cowpeas, females of all three strains laid between 80 and 90 eggs. Only one or two adults of the Yemen strain emerged from cowpeas irrespective of the initial number of eggs present, compared with the ten or more adults of the other two strains which emerged when the cowpea bore numerous eggs. The daily levels of oviposition did not differ among the strains when females had access to cowpeas changed daily for others bearing no eggs. The periods of development differed among the three strains, the greatest median value being 33 days in the Yemen strain where the greatest individual variation in development times was also noted. The significance of the results to the development of possible control measures for this pest is discussed.