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1.
利用生长速率法、活体接种试验法、自然感病试验法研究了韭菜提取物对芒果炭疽病菌colletotrichum gloeosporioides Penz.和芒果蒂腐病菌Botryodiplodia theobromae Pat.的抑制作用。结果表明韭菜提取物对芒果炭疽菌和芒果蒂腐菌都具有抑制作用,其有效中浓度(EC50)分别为3.6%、5.8%;活体接种试验中,用试液处理,从开始有发病情况出现的第5天,能使芒果在20℃的条件下,其由外接芒果炭疽菌引发的芒果炭疽病发病率为8%~19%,抑菌率为67.7%~88.6%,而对照组的发病率为100%;在芒果自然感病试验中,韭菜提取物处理芒果也能够明显减轻芒果蒂腐病的发病程度。  相似文献   

2.
鲜洋葱和干洋葱挥发性化学成分比较   总被引:1,自引:0,他引:1  
孙雪君  徐怀德  米林峰 《食品科学》2012,33(22):290-293
采用固相微萃取方法,用气相色谱-质谱联用结合计算机谱图检索,对两个不同品种的鲜洋葱和干洋葱挥发性化学成分进行分析鉴定。结果表明:鲜洋葱和干洋葱样品共鉴定出挥发性成分49种,各样品挥发性成分种类分别为30、28、28种和25种,分别占其色谱流出组分总量的94.25%、96.01%、83.40%和86.11%它们主要是含硫化合物、醇类、醛类和酯类等;干洋葱挥发性成分与新鲜洋葱相比在组成和相对含量都存在着较大差异。  相似文献   

3.
《Food chemistry》2005,93(2):205-214
An analysis of the polar extracts from seeds of Allium caepa L. var. tropeana led to the isolation of eight furostanol saponins, one of which was previously reported in the literature. On the basis of 1D, 2D NMR and mass spectrometry data, the structures of the compounds were elucidated as 1-O-β-D-glucopyranosyl-(25R)-furost-5(6)-en-1β,3β,22α,26-tetraol-26-O-α-L-rhamnopyranosyl-(1‴  2″)-O-α-L-arabinopyranoside (1a), its epimer at position 22, 1-O-β-D-glucopyranosyl-(25R)-furost-5(6)-en-1β,3β,22β,26-tetraol-26-O-α-L-rhamnopyranosyl-(1‴  2″)-O-α-L-arabinopyranoside (1b), 1-O-β-D-glucopyranosyl-22-O-methyl-(25R)-furost-5(6)-en-1β,3β,22ξ,26-tetraol-26-O-α-L-rhamnopyranosyl-(1‴  2″)-O-α-L-arabinopyranoside (probably artefact) (2), 1-O-β-D-glucopyranosyl-(25R)-furost-5(6)-en-1β,3β,22β,26-tetraol-26-O-α-L-rhamnopyranosyl-(1‴  6″)-O-β-D-galactopyranoside (3), 1-O-β-D-glucopyranosyl-22-O-methyl-(25R)-furost-5(6)-en-1β,3β,22ξ,26-tetraol-26-O-α-L-rhamnopyranosyl-(1‴  6″)-O-β-D-galactopyranoside (probably artefact) (4), 26-O-β-D-glucopyranosyl-(25R)-furost-5(6)-en-3β,22α,26-triol-3-O-α-L-rhamnopyranosyl-(1″  2′)-O-[β-D-glucopyranosyl-(1‴  6′)-O]-β-D-glucopyranoside (5a) and its epimer at position 22,26-O-β-D-glucopyranosyl-(25R)-furost-5(6)-en-3β,22β,26-triol-3-O-α-L-rhamnopyranosyl-(1″  2′)-O-[β-D-glucopyranosyl-(1‴  6′)-O]-β-D-glucopyranoside (5b) and the known compound 26-O-β-D-glucopyranosyl-22-O-methyl-(25R)-furost-5(6)-en-3β,22ξ,26-triol-3-O-α-L-rhamnopyranosyl-(1″  2′)-O-[β-D-glucopyranosyl-(1‴  6′)-O]-β-D-glucopyranoside (6) [Mimaki, Y., Satou, T., Kuroda, M., Sashida, Y., & Hatakeyama, Y. (1999). Steroidal saponins from the bulbs of Lilium candidum. Phytochemistry, 51, 567–573]. This is the first report on furostanol saponins in the seeds of Allium caepa L. var. tropeana.  相似文献   

4.
In the outer layers of pickled or canned onions there appears, at times, yellow colorations or deposits of yellow substances. The pigment has been identified as quercetin, a normal component of onion skins; this alteration is furthermore found to be totally innocuous.  相似文献   

5.
采用最低抑菌浓度(MIC)和滤纸片法研究了洋葱乙醇提取物对枯草芽孢杆菌、金黄色葡萄球菌、大肠杆菌、黑曲霉和酵母菌的抑制作用,同时研究了洋葱醇提物(OEE)的抑菌持久性及温度对它的影响.结果表明,OEE时各实验菌种均有一定的抑制作用,其中对酵母菌的抑制作用尤其显著,最低抑菌浓度达到3.2g/mL;OEE对各实验菌株具有较好的抑菌持久性,并且在一定范围内,温度对它有显著影响.  相似文献   

6.
为了明确大蒜对不同烤烟品种的化感作用,进行了大蒜挥发物、提取物及种过大蒜的土壤(0~10cm)对不同烤烟品种种子发芽率、种苗生长及成苗生长等的影响试验.结果表明:大蒜对不同烤烟品种具有一定的化感作用.不同烤烟品种的化感程度不同,对同一烤烟品种发芽、苗高及根长的化感作用或程度也不尽相同.其中.新鲜大蒜挥发物对烤烟种苗鲜物质的积累具有明显抑制作用,抑制率33.91%~57.89%;新鲜大蒜乙醇提取物对不同烤烟品种发芽具有较强的抑制作用,抑制率为7.00%~100%;种过大蒜的土壤可抑制不同烤烟品种种苗鲜物质的积累,抑制率为8.35%~60.96%.但大蒜提取物及种过大蒜的土壤对不同烤烟品种成苗无显著的抑制作用,说明在目前的烟草种植模式下,采用大蒜作为烤烟的轮作作物时,可不考虑大蒜对烤烟生长负面化感作用的影响.  相似文献   

7.
BACKGROUND: The in vitro antifungal activity of zimmu (Allium cepa L. × Allium sativum L.) extract against Aspergillus flavus Link., Fusarium moniliforme Sheld, Curvularia lunata (Wakker) Boedijn and Alternaria alternata (Fr.) Keissler, the fungi associated with grain mold of sorghum, was evaluated. An emulsifiable concentrate (EC) formulation of zimmu extract was prepared and its efficacy in controlling grain mold was tested under field conditions. RESULTS: The leaf extract of zimmu exhibited strong antifungal activity against A. flavus, F. moniliforme, C. lunata and A. alternata and caused in vitro fungal growth inhibition of 73.3%, 71.1%, 70.0% and 74.4%, respectively. Foliar application of zimmu formulation 50 EC at 3 mLL?1 (v/v) concentration 60, 75 and 90 days after sowing significantly reduced the incidence of grain mold and increased the grain weight and grain hardness. A significant reduction in the aflatoxin B1 content in sorghum grains was observed when sorghum plants were sprayed with zimmu formulation 50 EC at 0.3% concentration. Western blot analysis revealed that a thaumatin‐like protein (TLP) a molecular mass of 23 kDa that cross‐reacted with zeamatin antiserum was expressed at higher levels in sorghum grains after treatment with zimmu formulations. CONCLUSION: The leaf extract of zimmu exhibited antifungal activity against sorghum grain mold fungi. The formulated zimmu extract was significantly effective in reducing the grain mold incidence in sorghum under field conditions. This formulated zimmu extract offers a novel alternative for eco‐friendly management of grain mold of sorghum. Copyright © 2007 Society of Chemical Industry  相似文献   

8.
新疆洋葱籽油脂肪酸组成研究   总被引:2,自引:1,他引:1  
采用气相色谱-质谱联用法(GC/MS)对新疆洋葱籽油中脂肪酸组成及相对含量进行研究.结果表明,新疆洋葱籽油由棕榈酸、亚油酸、油酸等12种脂肪酸组成,不饱和脂肪酸达79.92%,其中油酸为13.11%,亚油酸为65.90%,棕榈酸为10.47%,硬脂酸为4.97%.  相似文献   

9.
采用碱溶酸沉正交法对分蘖葱头中蛋白质进行提取工艺优化,并对其基础特性进行测定,结果表明在料液比1∶15(g/mL)、pH 9.0、提取温度50?℃、提取时间1.5?h条件下提取率最大为79.38%。电泳结果表明蛋白分子质量分别为61.94、27.10、17.62、13.34 kDa。高效液相色谱法测得分蘖葱头蛋白中必需氨基酸质量分数为38.96%,非必需氨基酸质量分数为61.04%。二级结构测定结果表明分蘖葱头蛋白中α-螺旋含量为52.60%,β-折叠含量为8.60%,β-转角含量为15.60%,无规则卷曲含量为22.40%。采用红外图谱法对分蘖葱头蛋白特征官能团进行测定,其特征官能团明显。  相似文献   

10.
贾庆超  梁艳美 《中国调味品》2022,(1):133-139,156
以新鲜无腐烂的山葱花为主要原料,以感官评价为指标,添加花椒、八角、小茴香等辅料1和小米椒、生姜、食盐等辅料2研制香辣山葱花酱.首先对影响香辣山葱花酱主要风味的辅料1花椒、八角、小茴香和辅料2生姜、食盐、白糖进行单因素试验和正交试验.其次,为了得到最优工艺条件,根据正交试验结果,将辅料1、辅料2、白糖、菜籽油4个因素进行...  相似文献   

11.
以毛葱为原料,利用乙醇在超声波辅助下提取毛葱黄酮,经AB-8大孔吸附树脂纯化,通过三氯化铝和浓氨水定性试验,确定所制备的产品为纯度较高的毛葱黄酮。通过考察影响黄酮得率的主要3个因素乙醇浓度,超声时间,超声温度,利用响应面法确定毛葱黄酮的最佳提取工艺为:乙醇浓度为85.12%,提取温度为61.11℃,提取时间28.2 min,黄酮提取率达到2.024%。  相似文献   

12.
Dry bulb onions and leeks, at the marketable stage of development, were dissected into nine and ten fractions respectively, comprising the stem and leaves in succession from the oldest outer layers. Each fraction was separately analysed for flavour components by determination of thiosulphinate and pyruvate. Similarly, garlic cloves were divided into five fractions. There was a consistent pattern of flavour distribution in the seven onion varieties studied. The dried outer scales were virtually free from flavour components, the concentrations of which (on a fresh weight basis) increased progressively from a minimum value in the outer leaf to the innermost tissue and the stem. The latter often contained more than twice the concentration present in the outer leaf. The pattern in the roots and edible portions of leek differed in detail from that in onion. Flavour intensity increased progressively from the outer leaf to the inner tissues and the concentrations in both the roots and the stem were approximately equivalent to that of the fourth leaf numbered from the outer leaf. The pattern of flavour distribution in garlic cloves was simpler than that of onion and leek. The storage leaf accounted for the bulk of the weight of the clove as well as its flavour content. Some aspects of knowledge of the metabolism of inorganic nitrogen and sulphur compounds in roots and other tissues and transport of the corresponding metabolites have been briefly reviewed as the basis of a preliminary interpretation of the above observations. Attention has been drawn to the bearing of the results on preparation of onion for cooking and processing and on sampling for analysis.  相似文献   

13.
朱晓丹  贾春虹  王东  靖俊杰  贺敏 《食品科学》2019,40(21):150-155
为了明确氟啶胺在大葱和小葱上使用后的消解趋势和残留情况,2017年在北京、山东、内蒙古、江苏、四川和宁夏开展了氟啶胺39.5%(体积分数)悬浮剂在葱上的消解动态和最终残留试验。样品用乙腈提取,采用N-丙基乙二胺、石墨化炭黑和十八烷基碳混合分散吸附剂净化,通过超高效液相色谱分离、三重四极杆串联质谱检测,外标法定量进行氟啶胺残留与安全性评价。结果表明:氟啶胺在大葱上的降解半衰期为1.2 d,在小葱上的降解半衰期为8.7 d;在大葱上的最终残留量为<0.010~0.308 mg/kg;小葱上的最终残留量为0.100~5.738 mg/kg。中国未制定氟啶胺在大葱和小葱上的食品安全限量标准,欧盟、日本、韩国规定氟啶胺在葱上的最大允许残留限量标准分别为0.01、0.1、3.0 mg/kg。参照欧盟和日本的食品安全限量标准,氟啶胺在我国大葱和小葱上的残留量不安全。中国应加快制定氟啶胺在大葱和小葱上的食品安全限量标准,本研究为氟啶胺在葱上的安全使用和食品安全限量标准制定提供支持。  相似文献   

14.
紫皮洋葱油索氏提取工艺优化   总被引:2,自引:1,他引:1  
采用响应曲面法对紫皮洋葱油提取工艺进行优化。以紫皮洋葱油得率为指标,采用索氏提取法,对提取溶剂,提取时间,料液比和回流温度等提取条件进行单因素试验。在此基础上,根据Box-Benhnken中心组合方法进行三因素三水平的试验设计,并进行响应面分析。结果表明,紫皮洋葱油最佳提取工艺条件为:石油醚为溶剂,料液比为3.64/80(g:mL),提取时间为3.83h,回流温度为78.49℃。在此工艺条件下,紫皮洋葱油得率理论值为0.462%,实测值为0.470%,与理论值相比,相对误差为1.73%。  相似文献   

15.
该文采用抑菌圈法研究了大蒜的水提取物、乙醇提取物和酸性水溶液的提取物对蜡样芽孢杆菌的抑制作用.结果表明大蒜的乙醇提取物的抑菌效果好过水提取物,酸性的水溶液提取物效果最好,可以较好地控制蜡样芽孢杆菌的生长,有较好的应用前景.  相似文献   

16.
Food Science and Biotechnology - This study was conducted to examine the volatile compounds of cultivated dumebuchu (Allium senescens L. var. senescens). Dumebuchu is listed as a rare plant in...  相似文献   

17.
主要研究大蒜多糖提取的4种影响因素及其交互作用对大蒜多糖提取率的影响,借助于Design-Expert软件设计,优化大蒜多糖提取工艺条件,以期为开发利用大蒜多糖提供参考。采用水煮醇沉法提取大蒜多糖,以苯酚-硫酸法检测其含量,分别考察浸提时间、料液比、浸提温度及浸提次数对大蒜多糖得率的影响。在单因素试验的基础上,利用Design-Expert软件进行四因素三水平Box-Behnken试验设计,建立了大蒜多糖提取率和各因素之间的数学模型。结果表明,提取温度、液料比、提取时间和提取次数的一次项,个别交互项及其二次项对大蒜多糖得率的影响显著,而液料比与提取时间,液料比与提取次数的交互项作用不明显。大蒜多糖提取最优条件最终确定为:提取温度81℃,液料比14∶1(m L/g),提取时间84 min,提取次数2次。  相似文献   

18.
Abstract: In the present study the effects of individual and combined essential oils (EOs) extracted from onion (Allium
cepa
L.) bulb and garlic (Allium sativum L.) clove on the growth of Aspergillus versicolor and sterigmatocystin (STC) production were investigated. The EOs obtained by hydrodistillation were analyzed by GC/MS. Twenty one compounds were identified in onion EO. The major components were: dimethyl‐trisulfide (16.64%), methyl‐propyl‐trisulfide (14.21%), dietil‐1,2,4‐tritiolan (3R,5S‐, 3S,5S‐ and 3R,5R‐ isomers) (13.71%), methyl‐(1‐propenyl)‐disulfide (13.14%), and methyl‐(1‐propenyl)‐trisulfide (13.02%). The major components of garlic EO were diallyl‐trisulfide (33.55%), and diallyl‐disulfide (28.05%). The mycelial growth and the STC production were recorded after 7, 14, and 21 d of the A. versicolor growth in Yeast extract sucrose (YES) broth containing different EOs concentrations. Compared to the garlic EO, the onion EO showed a stronger inhibitory effect on the A. versicolor mycelial growth and STC production. After a 21‐d incubation of fungi 0.05 and 0.11 μg/mL of onion EO and 0.11 μg/mL of garlic EO completely inhibited the A. versicolor mycelial growth and mycotoxins biosynthesis. The combination of EOs of onion (75%) and garlic (25%) had a synergistic effect on growth inhibition of A. versicolor and STC production. Practical Application: A substitution of synthetic preservatives with natural antimicrobial compounds in food safety to control fungal contamination and mycotoxin production.  相似文献   

19.
以分蘖葱头为主要原料,以葡萄酒酵母、醋酸菌作为分蘖葱头保健醋饮料的酒精发酵菌种,通过正交试验与感官评价确定分蘖葱头醋酸发酵的最佳工艺参数为:初始酒精含量10%、仞始pH值5.0、醋母添加量10%、醋酸发酵时间5d,醋酸含最为6.12%.再经后熟、调配制营养丰富、口味独特的分蘖葱头保健醋饮料.  相似文献   

20.
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