Guo Ming, Wang Xiaomeng, Lu Xiaowang, Wang Hongzheng, Brodelius Peter E
School of Science, Zhejiang Agricultural & Forestry University, Lin'an 311300, China.
School of Forestry and Bio-technology, Zhejiang Agricultural & Forestry University, Lin'an 311300, China.
PLoS One. 2016 Sep 1;11(9):e0161566. doi: 10.1371/journal.pone.0161566. eCollection 2016.
In order to obtain the biological active compound, α-mangostin, from the traditional native mangosteen (Garcinia mangostana L.), an extraction method for industrial application was explored. A high yield of α-mangostin (5.2%) was obtained by extraction from dried mangosteen pericarps with subsequent purification on macroporous resin HPD-400. The chemical structure of α-mangostin was verified mass spectrometry (MS), nuclear magnetic resonance (1H NMR and 13C NMR), infrared spectroscopy (IR) and UV-Vis spectroscopy. The purity of the obtained α-mangostin was 95.6% as determined by HPLC analysis. The binding of native α-mangostin to human serum albumin (HSA) or transferrin (TRF) was explored by combining spectral experiments with molecular modeling. The results showed that α-mangostin binds to HSA or TRF as static complexes but the binding affinities were different in different systems. The binding constants and thermodynamic parameters were measured by fluorescence spectroscopy and absorbance spectra. The association constant of HSA or TRF binding to α-mangostin is 6.4832×105 L/mol and 1.4652×105 L/mol at 298 K and 7.8619×105 L/mol and 1.1582×105 L/mol at 310 K, respectively. The binding distance, the energy transfer efficiency between α-mangostin and HSA or TRF were also obtained by virtue of the Förster theory of non-radiation energy transfer. The effect of α-mangostin on the HSA or TRF conformation was analyzed by synchronous spectrometry and fluorescence polarization studies. Molecular docking results reveal that the main interaction between α-mangostin and HSA is hydrophobic interactions, while the main interaction between α-mangostin and TRF is hydrogen bonding and Van der Waals forces. These results are consistent with spectral results.
为了从传统的本地山竹（莽吉柿，Garcinia mangostana L.）中获取生物活性化合物α-倒捻子素，探索了一种适用于工业应用的提取方法。通过用大孔树脂HPD-400对干燥的山竹果皮进行提取和后续纯化，获得了高产率的α-倒捻子素（5.2%）。通过质谱（MS）、核磁共振（1H NMR和13C NMR）、红外光谱（IR）和紫外可见光谱对α-倒捻子素的化学结构进行了验证。通过高效液相色谱（HPLC）分析测定，所获得的α-倒捻子素的纯度为95.6%。通过光谱实验与分子模拟相结合的方法，研究了天然α-倒捻子素与人血清白蛋白（HSA）或转铁蛋白（TRF）的结合。结果表明，α-倒捻子素以静态复合物的形式与HSA或TRF结合，但在不同系统中的结合亲和力不同。通过荧光光谱和吸收光谱测量了结合常数和热力学参数。在298 K时，HSA或TRF与α-倒捻子素结合的缔合常数分别为6.4832×105 L/mol和1.4652×105 L/mol，在310 K时分别为7.8619×105 L/mol和1.1582×105 L/mol。借助Förster非辐射能量转移理论，还获得了α-倒捻子素与HSA或TRF之间的结合距离、能量转移效率。通过同步光谱和荧光偏振研究分析了α-倒捻子素对HSA或TRF构象的影响。分子对接结果表明，α-倒捻子素与HSA之间的主要相互作用是疏水相互作用，而α-倒捻子素与TRF之间的主要相互作用是氢键和范德华力。这些结果与光谱结果一致。
