Department of Environmental Biology, Sapienza University of Rome, Rome, Italy.
Plant Physiol Biochem. 2012 Aug;57:54-8. doi: 10.1016/j.plaphy.2012.04.014. Epub 2012 May 8.
Hypericum perforatum is a well-known medicinal plant. Among all secondary metabolites produced by this species, xanthones are very interesting for their antifungal activity. In the present study, with the aim to improve xanthone production and antifungal activity of H. perforatum subsp. angustifolium (sin. Fröhlich) Borkh in vitro roots, a new methodology consisting of a three-step culture system, has been developed. Regenerated roots of H. perforatum were cultured in a three-step culture system: in the first step, to increase biomass, the roots were cultured in half-strength liquid Murashige and Skoog (MS) medium supplemented with 1 mg L(-1) indole butyric acid (IBA) and 1.5% sucrose. In the second and third steps, to stimulate secondary metabolism, the roots were cultured with 1.1 mg L(-1) 2,4-dichlorophenoxyacetic acid (2,4-D), 0.215 mg L(-1) kinetin (KIN), and 0.186 mg L(-1) 1-naphthalenacetic acid (NAA). In the third step, some of the roots were treated with chitosan. Xanthone production increased 2.7 times following the three-step method. The mean minimal inhibitory concentration (MIC) values were of 36.9, 26.7, and 65 μg mL(-1), against Candida species, Cryptococcus neoformans and dermatophytes, respectively. A positive correlation between xanthone accumulation and antifungal activity has been shown.
贯叶金丝桃是一种广为人知的药用植物。在该物种产生的所有次生代谢产物中，黄烷酮因其抗真菌活性而非常有趣。在本研究中，为了提高贯叶金丝桃亚种（Fröhlich）Borkh 体外根的黄烷酮产量和抗真菌活性，开发了一种由三步培养系统组成的新方法。贯叶金丝桃的再生根在三步培养系统中进行培养：在第一步中，为了增加生物量，根在半强度液体 Murashige 和 Skoog（MS）培养基中培养，其中添加 1 mg L(-1)吲哚丁酸（IBA）和 1.5%蔗糖。在第二步和第三步中，为了刺激次生代谢，根在 1.1 mg L(-1) 2,4-二氯苯氧乙酸（2,4-D）、0.215 mg L(-1)激动素（KIN）和 0.186 mg L(-1) 1-萘乙酸（NAA）的培养基中培养。在第三步中，一些根用壳聚糖处理。三步法后黄烷酮产量增加了 2.7 倍。对念珠菌属、新生隐球菌和皮肤真菌的最小抑菌浓度（MIC）平均值分别为 36.9、26.7 和 65 μg mL(-1)。已显示黄烷酮积累与抗真菌活性之间存在正相关。
