TY - JOUR AU - Do, Vu Van AU - Thang, Nguyen Tien AU - Suong, Ngo Ke PY - 2014/11/11 Y2 - 2024/03/28 TI - Investigation of the contents of three main bio-active substances in the seed oil of the neem trees planted in Ninh Thuan province, Vietnam. JF - Academia Journal of Biology JA - AJB VL - 27 IS - 3 SE - Articles DO - 10.15625/0866-7160/v27n3.5272 UR - https://vjs.ac.vn/index.php/vjbio/article/view/5272 SP - 61-65 AB - <p>By the cold pressing method of the neem (<em>Azadirachta indica</em> A. Juss) seed kernels at 40<sup>o</sup>C, we have received 32.6% neem oil and 67.4% neem cake. The results of the analysis on high performance liquid chromatography (HPLC) and gas chromatography (GC) showed that there were three main bio-active substances: azadirachtin, salanin and nimbin in the neem oil and neem cake; the azadirachtin contents in the neem cake were 6 times higher than that in the neem oil. The neem oil consisted of 9 saturated and unsaturated fatty acids; among them, the oleic acid (C18<sup>=</sup>)contents were the highest (43%-48%) and the lauric acid (C12) contents were the lowest (trace-0.12%).</p> <p>The 15 pestiside formulations from the neem oil and  neem oil with Bt  were made and tested on <em>Heliothis armigera</em> and <em>Plutella xylostella</em>. The results showed that the neem oil itself and neem oil with Bt all affected to kill actively the insects.</p> ER -