Determination of total flavonoids in Abrus cantoniensis and its dynamic changes / 中国中药杂志

<p><b>OBJECTIVE</b>To develop a method for ultrasonic extraction and determination of total flavonoids in Abrus cantoniensis, and to analyze its dynamic changes.</p><p><b>METHOD</b>The optimized condition of extraction of total flavonoids was studied with orthogonal design. The contents of total flavonoids in different organs and of different growth stages were determined by UV-visible spectrophotometer.</p><p><b>RESULT</b>The ethanol volume and extraction times were the main factors impacting the effects of ultrasonic extraction. The content of total flavonoids in stems were higher than in roots and the lowest in leaves. The dynamic changes of total flavonoids contents in roots and stems of A. cantoniensis were in similar trends. Its total flavonoids content in the two parts of plant increased gradually with the growth and reached the maximum in October, and the content decreased significantly in Feburay of next year. The content of total flavonoids in leaves reached also to the highest value before leaves fell off.</p><p><b>CONCLUSION</b>The optimized extraction method of total flavonoids in Abrus contoniensis was obtained with three times with 80% ethanol at 20 times of volume for 30 min. The results implied that the best yield and quality may be obtained before leaves fall.</p>

Isolation and biological characteristics of rhizobia strains from Abrus cantoniensis / 中国中药杂志

<p><b>OBJECTIVE</b>The research aimed at studying the biological characteristics of rhizobia isolated from Abrus cantoniensis.</p><p><b>METHOD</b>The rhizobia strains, isolated from different environments in Guangxi, were studied for their growing characters and the generation time. They were also compared for survival capabilities under stresses caused by NaCl, pH, temperature, and different kinds and concentration of antibiotics.</p><p><b>RESULT</b>The strains obtained from A. cantoniensis in subtropical zone produced alkali in YMA medium, the average generation time was 14.8 hours, and thus they belong to slow-growing rhizobia. Rhizobia strains differed greatly in respect to tolerance of high temperature, adaptability of acidic environment and sensitivity to four antibiotics, but they had the same abilities of using different carbon and nitrogen sources. After 70 days from inoculated strains, the seedling formed nodules on the root (85.0%), and the dry matter of vine was increased by 51.1%.</p><p><b>CONCLUSION</b>The rhizobia strains isolated from different ecological environments are good germplasm resources of tolerances to high temperature and acidic environment. The research will greatly help utilize the rhizobia resources and enhance the quality of crude drugs of medicinal leguminosae.</p>

Effects of different nitrogenous compounds on growth and nodulation of Abrus cantoniensis / 中国中药杂志

<p><b>OBJECTIVE</b>The research aimed at the effects of different nitrogenous compounds on growth and nodulation of Abrus cantoniensis.</p><p><b>METHOD</b>After the seedlings of the herb were inoculated with rhizobia in potted culture, they were supplied with nutrition solutions which contained the three nitrogenous compounds, KNO3, NH4NO3, (NH4)2SO4 of different nitrogen concentration. The growth and nodulation of seedlings was determined after 70 days.</p><p><b>RESULT</b>Different nitrogenous compounds were able to enhance the vegetable growth of seedlings variously. The effect of (NH4)2SO4 and NH4NO3 on growth was better than that of KNO3. Seedlings nodulation was obviously inhibited by these nitrogenous compounds. Their inhibitory effects ranked NH4NO3 > (NH4)2SO4 > KNO3. The treatments of KNO3 and the lower concentration treatments of NH4NO3 and (NH4)2 SO4 didn't inhibit the nodulation of seedlings, but the higher concentration treatment of NH4NO3 and (NH4)2SO4 severely inhibited nodulation or even made a no formation of nodule.</p><p><b>CONCLUSION</b>The results showed that ammonium nitrogen the higher inhibitory ability to the nodulation of seedlings of A. cantoniensis than nitrate nitrogen. Therefore, the application of ammonium nitrogen fertilizer should be controlled in culture of the herb, which is in favor of increasing the function of biological nitrogen fixation and the quality of the medicinal materials of A. cantoniensis.</p>