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排序方式: 共有358条查询结果,搜索用时 15 毫秒
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龙眼蜜为台湾特色蜂蜜,备受消费者喜爱。然而,市面上充斥以糖浆调制的人造龙眼蜜,不仅侵害了消费者的权益,也影响正规龙眼蜜的产销,损害了台湾蜂农的利益。本研究针对龙眼蜜含有花粉粒的特性,利用酵素免疫分析的技术,开发龙眼蜂蜜的鉴定方法。采取确定来源的龙眼蜜稀释后离心取沉淀,以Na—bicarbonate冰温萃取花粉成分,经透析浓缩后作为抗原,用Freund完全佐剂乳化,免疫BALB/c雌性小鼠,每隔3-4周再补强注射。补强免疫后10-14天采血分离血清,以ELISA测抗体力价。结果显示,龙眼蜜的花粉萃取液能有效诱发小鼠免疫反应,产生的多源抗体能区别真蜜与合成蜜。 相似文献
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研究确立了蜂蜜中甲砜霉素残留的高效液相色谱检测的方法。样品经碱性乙酸乙酯提取,旋转蒸发进行浓缩,C18固相萃取柱萃取净化,在225 nm波长下用紫外检测器进行检测。通过前处理条件的优化大大减少了基质的干扰,甲砜霉素的最低检测限达到30μg.kg-1,低于中华人民共和国行业标准SN 0199-93中规定的50μg.kg-1;平均回收率在71.3%~90.9%之间,变异系数为2.0%~3.4%。该方法精密度和重现性良好,适用于蜂蜜中甲砜霉素的检测。 相似文献
85.
A wind tunnel study was conducted to determine pesticide deposition on commonly used windbreak tree species used as spray drift barriers and associated exposure of honey bees. Although it has been known that windbreaks are effective in reducing chemical drift from agricultural applications, there is still an enormous information and data gap on details of the dependence of the mechanism on the biological materials of the barriers and on standardization of relevant assessment methods. Beneficial arthropods like honey bees are adversely affected by airborne drift of pesticides. A study was initiated by first establishing a wind tunnel to create a controlled environment for capture efficiency work. Suitable spray parameters were determined after a preliminary study to construct and develop a wind tunnel protocol. A tracer dye solution was sprayed onto the windbreak samples and honey bees located in the wind tunnel at various simulated wind speeds. Analysis of data from this work has shown that needle-like foliage of windbreak trees captures two to four times more spray than broad-leaves. In addition, it was determined that, at lower wind speeds, flying bees tend to capture slightly more spray than bees at rest. 相似文献
86.
温度、柠檬酸和抗环血酸对冬蜜中多酚氧化酶活性的影响 总被引:1,自引:0,他引:1
以儿茶酚为底物,采用紫外分光光度法,测定冬蜜中多酚氧化酶(PPO)的活性。结果表明,在20~90℃的条件下,冬蜜中PPO的活性,随着温度的升高而增强;在冬蜜中添加0.1%柠檬酸时,对其PPO活性抑制效果最好;但添加0.1%抗坏血酸(Vc)时,对其PPO活性抑制作用较弱。 相似文献
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Faucon JP Aurières C Drajnudel P Mathieu L Ribière M Martel AC Zeggane S Chauzat MP Aubert MF 《Pest management science》2005,61(2):111-125
Two groups of eight honey bee colonies were fed with two different concentrations of imidacloprid in saccharose syrup during summer (each colony was given 1 litre of saccharose syrup containing 0.5 microg litre(-1) or 5 microg litre(-1) of imidacloprid on 13 occasions). Their development and survival were followed in parallel with control hives (unfed or fed with saccharose syrup) until the end of the following winter. The parameters followed were: adult bee activity (number of bee entering the hive and pollen carrying activity), adult bee population level, capped brood area, frequency of parasitic and other diseases, mortality, number of frames with brood after wintering and a global score of colonies after wintering. The only parameters linked to feeding with imidacloprid-supplemented saccharose syrup when compared with feeding with non-supplemented syrup were: a statistically non-significant higher activity index of adult bees, a significantly higher frequency of pollen carrying during the feeding period and a larger number of capped brood cells. When imidacloprid was no longer applied, activity and pollen carrying were re-established at a similar level for all groups. Repeated feeding with syrup supplemented with imidacloprid did not provoke any immediate or any delayed mortality before, during or following the next winter, whereas such severe effects are described by several French bee keepers as a consequence of imidacloprid use for seed dressing in neighbouring cultures. In any case, during the whole study, mortality was very low in all groups, with no difference between imidacloprid-fed and control colonies. Further research should now address several hypotheses: the troubles described by bee keepers have causes other than imidacloprid; if such troubles are really due to this insecticide, they may only be observed either when bees consume contaminated pollen, when no other sources of food are available, in the presence of synergic factors (that still need to be identified), with some particular races of bees or when colonies are not strong and healthy. 相似文献
89.
蜂蜜中双甲脒残留量检测方法 总被引:2,自引:0,他引:2
本文建立了蜂蜜中双甲脒残留量的气相色谱分析方法,并对萃取溶剂及衍生化试剂等8进行了讨论。蜂蜜中的双脒经水解、净化和衍生化后,用气相色谱-电子捕获检测器测定。其回收率为90.5% ̄100.1%,变异系数1.64% ̄4.40%,最低检测浓度为0.0025mg/kg。 相似文献
90.