Kulakowski Daniel M, Wu Shi-Biao, Balick Michael J, Kennelly Edward J
Department of Biological Sciences, Lehman College and The Graduate Center, City University of New York, 250 Bedford Park Boulevard West, Bronx, NY 10468, USA.
Institute of Economic Botany, The New York Botanical Garden, Bronx, NY 10458, USA.
J Chromatogr A. 2014 Oct 17;1364:74-82. doi: 10.1016/j.chroma.2014.08.049. Epub 2014 Aug 20.
This study presents a strategy based on repeatable reversed-phase LC-TOF-MS methods and chemometric statistical tools, including untargeted PCA and supervised OPLS-DA models, to identify low-yielding compounds with potent immunostimulant activity in Phaleria nisidai (Thymelaeaceae), a plant with a history of use as an adaptogen on the islands of Palau in Micronesia. IFNγ ELISA assays were used to classify chromatographic fractions according to imunomodulatory activity prior to LC-TOF-MS chemometric analysis to target and identify compounds likely to contribute to observed activity. Simplexin, a daphnane diterpene ester, was identified for the first time from this genus and caused an increase in the production of cytokines (IFNγ, IL1β, IL6, and IL13) by peripheral blood mononuclear cells. Five other daphnane diterpene esters were tentatively identified for the first time from this plant based on mass spectral data and are marker metabolites distinguishing active from inactive fractions. This analytical approach increased the efficiency of bioactivity-guided fractionation and has the potential to minimize redundant isolation and identify minor constituents with potent activity from a complex matrix.
本研究提出了一种基于可重复的反相液相色谱-飞行时间质谱方法和化学计量学统计工具的策略，包括非靶向主成分分析（PCA）和有监督的正交投影到潜在结构判别分析（OPLS-DA）模型，以鉴定密克罗尼西亚帕劳群岛上具有适应原使用历史的植物尼西代巴豆（瑞香科）中具有强大免疫刺激活性的低产化合物。在进行液相色谱-飞行时间质谱化学计量分析以靶向和鉴定可能对观察到的活性有贡献的化合物之前，使用干扰素γ（IFNγ）酶联免疫吸附测定（ELISA）根据免疫调节活性对色谱馏分进行分类。首次从该属中鉴定出一种瑞香烷二萜酯——辛普立新，它可使外周血单核细胞产生的细胞因子（IFNγ、白细胞介素1β、白细胞介素6和白细胞介素13）增加。基于质谱数据，首次从该植物中初步鉴定出其他五种瑞香烷二萜酯，它们是区分活性馏分和非活性馏分的标记代谢物。这种分析方法提高了生物活性导向分馏的效率，并且有可能最大限度地减少冗余分离，并从复杂基质中鉴定出具有强大活性的次要成分。
