Department of Pharmaceutical Technology, Faculty of Pharmaceutical Science, Khon Kaen University, Muang, Khon Kaen, Thailand.
National Synchrotron Radiation Research Center, Hsinchu City, Taiwan, Republic of China.
PLoS One. 2018 Jul 2;13(7):e0199696. doi: 10.1371/journal.pone.0199696. eCollection 2018.
Wood ashes infused with water have been traditionally used as hair cosmetics, but little or no research has examined the effects of ash on human hair. This study investigated the effect of eucalyptus ash on the structure and morphology of excised human grey hair and its potential use as a pretreatment in natural hair dyeing using anthocyanins extracted from purple cops of Zea mays. Tensile characteristics and surface morphology of ash-pretreated hair was monitored by texture analysis, scanning electron microscopy and atomic force microscopy. The biochemical characteristics of ash-treated hair were analyzed by synchrotron radiation-FTIR and sulfur K-edge X-ray absorption near edge. Dyeing with anthocyanins was analyzed by Lab color scale and adsorption of anthocyanins. Ash-treated hair was elastically and plastically deformed with microscopic alterations to the ridges of the cuticle cells, similar to ammonia-treated hair. The ash extract significantly changed the relative proportion of alpha-helices in the cuticle and cortex layers (p < 0.05), but did not affect the interaction of S-bonds with neighboring atoms (p > 0.05). Ash-treated hair showed significantly enhanced adsorption of anthocyanins (p < 0.05) which changed the color of the grey hair. The alteration of secondary proteins in the cuticle and cortex layers of the grey hair by ash extract pre-treatment, enhanced anthocyanin adsorption. The eucalyptus ash could potentially be useful as a natural hair dyeing pre-treatment.
木灰经水浸泡后一直被传统用作头发化妆品，但对灰分对人类头发的影响的研究甚少或几乎没有。本研究探讨了桉木灰对人发灰分的结构和形态的影响，以及其作为天然染发剂中提取的矢车菊素预处理剂的潜在用途。通过纹理分析、扫描电子显微镜和原子力显微镜监测灰分预处理头发的拉伸特性和表面形貌。通过同步辐射傅里叶变换红外光谱和硫 K 边 X 射线吸收近边结构分析灰分处理头发的生化特性。通过 Lab 颜色刻度和矢车菊素的吸附分析对其进行染色。灰分处理的头发发生弹性和塑性变形，角质层细胞的脊发生微观变化，类似于氨处理的头发。灰分提取物显著改变了角质层和皮质层中α-螺旋的相对比例（p < 0.05），但不影响 S 键与相邻原子的相互作用（p > 0.05）。灰分处理的头发对矢车菊素的吸附显著增强（p < 0.05），从而改变了灰发的颜色。灰分提取物预处理改变了灰发角质层和皮质层中的二级蛋白质，从而增强了矢车菊素的吸附。桉木灰可能可作为天然染发剂预处理剂。
