Objetive: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora(Syn. Cassia tora) against cowpea weevil(Callosobruchus maculatus).Metho...Objetive: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora(Syn. Cassia tora) against cowpea weevil(Callosobruchus maculatus).Method: The activities were evaluated using standard protocols.In these bioassays, the cowpea seeds were used directly as an insect feed. The activity of the extract and isolated compounds were tested at concentrations of 100, 200 and 300 μg/mL and compared to neem oil and cinnamaldehyde(as standard positive controls). Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2 D-NMR and ESI-MS studies.Results: Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone,aurantio-obtusin(1) and a novel compound that was named as cassiatorin(2). Compounds1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls.Conclusions: It is thus concluded that Senna tora extracts and the isolated compounds(1 and2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants.展开更多
为了测定决明不同组织中大黄酚和橙黄决明素的含量。分别收集了决明种子、根、茎、花、叶、果荚、子叶、胚轴、愈伤与不定根等组织,利用回流提取法提取大黄酚与橙黄决明素,高效液相色谱法(HPLC)进行含量测定。采用依利特反相色谱柱,以...为了测定决明不同组织中大黄酚和橙黄决明素的含量。分别收集了决明种子、根、茎、花、叶、果荚、子叶、胚轴、愈伤与不定根等组织,利用回流提取法提取大黄酚与橙黄决明素,高效液相色谱法(HPLC)进行含量测定。采用依利特反相色谱柱,以大黄酚和橙黄决明素为指标,以乙腈-0.1%磷酸水为流动相进行梯度洗脱,流速1 m L/min,检测波长为284 nm,柱温30℃。结果表明:大黄素型蒽醌类化合物在决明中的分布具有明显的组织特异性,其中,决明种子、胚轴、不定根、子叶与愈伤组织中含有大黄酚与橙黄决明素,决明根中仅含有大黄酚,其余组织不含有大黄酚与橙黄决明素,其余总蒽醌含量依次为子叶>不定根>愈伤组织>胚轴>根>花。决明种子成熟过程中,大黄酚的含量呈现"波浪式上升"的趋势,峰值出现在11月下旬;而橙黄决明素的含量呈现"先上升后下降"的趋势,峰值出现在11月中旬。由于大黄酚与橙黄决明素的含量在决明不同成熟时期分别出现峰值,建议采收11月下旬的决明种子以获得大黄酚,采收11月中上旬的决明种子以获得较多的橙黄决明素。展开更多
基金The financial assistance from the Swedish International Development Agency for some of the study (travel grant for Valantine Mbatchou)
文摘Objetive: To explore the potential insecticidal, ovipositor deterrent and antifeedant effects of ethyl acetate extract of the seeds of Senna tora(Syn. Cassia tora) against cowpea weevil(Callosobruchus maculatus).Method: The activities were evaluated using standard protocols.In these bioassays, the cowpea seeds were used directly as an insect feed. The activity of the extract and isolated compounds were tested at concentrations of 100, 200 and 300 μg/mL and compared to neem oil and cinnamaldehyde(as standard positive controls). Phytochemical analysis of the ethyl acetate extract was done through a number of chromatographic techniques and the structures of the isolated compounds were established through comprehensive spectroscopic analysis including 2 D-NMR and ESI-MS studies.Results: Fractionation of the active ethyl acetate extract resulted in the isolation of one known anthraquinone,aurantio-obtusin(1) and a novel compound that was named as cassiatorin(2). Compounds1 and 2 showed comparable insect antifeedant properties with the positive controls while their insecticidal and ovipositor deterrent effects were far superior to the standard controls.Conclusions: It is thus concluded that Senna tora extracts and the isolated compounds(1 and2) may be employed in the postharvest management of stored cowpea seeds and as other crop protectants.
文摘为了测定决明不同组织中大黄酚和橙黄决明素的含量。分别收集了决明种子、根、茎、花、叶、果荚、子叶、胚轴、愈伤与不定根等组织,利用回流提取法提取大黄酚与橙黄决明素,高效液相色谱法(HPLC)进行含量测定。采用依利特反相色谱柱,以大黄酚和橙黄决明素为指标,以乙腈-0.1%磷酸水为流动相进行梯度洗脱,流速1 m L/min,检测波长为284 nm,柱温30℃。结果表明:大黄素型蒽醌类化合物在决明中的分布具有明显的组织特异性,其中,决明种子、胚轴、不定根、子叶与愈伤组织中含有大黄酚与橙黄决明素,决明根中仅含有大黄酚,其余组织不含有大黄酚与橙黄决明素,其余总蒽醌含量依次为子叶>不定根>愈伤组织>胚轴>根>花。决明种子成熟过程中,大黄酚的含量呈现"波浪式上升"的趋势,峰值出现在11月下旬;而橙黄决明素的含量呈现"先上升后下降"的趋势,峰值出现在11月中旬。由于大黄酚与橙黄决明素的含量在决明不同成熟时期分别出现峰值,建议采收11月下旬的决明种子以获得大黄酚,采收11月中上旬的决明种子以获得较多的橙黄决明素。