ABSTRACT
Pueraria lobata is one of the most important medicinal herbs used traditionally in China. According to Shanghan Lun (Treatise on Exogenous Febrile Disease), it has been used traditionally to relieve body heat, eye soring, dry mouth, headache associated with high blood pressure, and stiff neck problems. Modern studies in the 1970s revealed that isoflavonoids extracted from P. lobata were the bioactive components of an herbal remedy namely Yufeng Ningxin Tablets for the treatment of patients after stroke. This article reviews recent application of P. lobota in the treatment of diabetics and in reducing alcohol drinking. In view of its low toxicity profile, P. lobota stands an excellent chance to be developed as a phytomedicine for treating human diseases.
ABSTRACT
Objective: To study the chemical constituents from the cane of Pueraria lobata. Methods: The compounds were isolated by column chromatography over silica gel and purified by Sephadex LH-20 column chromatography and preparative TLC. The structures were elucidated by means of physicochemical properties and spectroscopic analyses. Results: Eleven compounds were separated and identified as: dehydrovomifoliol (1), blumenol A (2), 3β-hydroxy-5α,6α- epoxy-7-megastigmen-9-one (3), liquiritigenin (4), garbanzol (5), ferulaldehyde (6), 2,4-dihydroxybenzaldehyde (7), 4-hydroxy-2-methoxybenzaldehyde (8), (-)-tuberosin (9), coumestrol (10), and β-sitosterol (11). Conclusion: Compounds 1-3 are sesquiterpenoids, which are firstly isolated from the plants of Pueraria DC., and compounds 4-8 are obtained from the plants of Pueraria DC. for the first time.
ABSTRACT
C-glucosyltransferase (EC 2.4.1.X) is one of the key enzymes for the biosynthesis of puerarin. This paper describes the methodology in purification and assay of the enzyme for the first time in Puerarin lobata (Willd.) Ohwi. C-glucosyltransferase from roots of P. lobata was extracted and partially purified by (NH4)2SO4 saturation. The effects of pH, temperature, and substrate concentration on the activity of the enzyme were investigated. The properties of the puerarin produced by C-glucosyltransferase were studied by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The peak activity of C-glucosyltransferase was detected in fraction of by 80% saturation of (NH4)2SO4 and the optimal conditions for enzymatic reaction were 35.5 μmol l-1 of isoliquiritigenin and 560 μmol l-1 of UDP-G at pH 8.1, 28oC for 1 h. Mn2+ at 1 mmol l-1 and Al3+ at 1 mmol l-1 increased the enzyme activity, while Mg2+ inhibited its activity. The enzyme activity in Nicotiana tabacum and P. lobata were detected under the above assay conditions. Higher activity was found in roots than in leaves and stems of P. lobata, while no enzyme activity was detected in leaves of N. tabacum. It was the first time that activity of C-glucosyltransferase, which transforms isoliquiritigenin to puerarin, was detected in P. lobata.
ABSTRACT
Object To establish cell suspension culture system in leaves of seedling of Pueraria lobata (Willd.) Ohwi Methods The callus induced from leaf explants of P.lobata seedling were suspended in liquid medium. The time courses of cell growth and yields of puerarin and isoflavones were studied Results The log phase of the cell cultures' growth was from 1st d through 5th d. The dry weight accumulation reached highest on 8th d. The production of puerarin was highly coupled with the cell growth. The yield of puerarin reached highest on 8th d. However, the accumulation of total isoflavones was different from that of puerarin. The yield of total isoflaones reached the highest on 10th d Conclusion The yield of total isoflavones in cell suspension culture system is higher than that in wild plants, while the yield of puerarin is lower than that in wild plants