Identification and Characterization of Methyl Isoeugenol Compound from the Golden Yellow Hued Muga Silk Fiber of India

ABSTRACT

Organic extraction of pigmentation constituents of the cocoons of Antheraea assamensis (muga) was investigated in this study. Chemical extraction of muga cocoon fibers and their host plant som (Machilus bombycina) leaves were carried out using two benign solvents: hexane and ethyl acetate. Thin-layer chromatography (TLC) revealed the presence of methyl isoeugenol and isoeugenyl acetate from extracts of cocoon fiber and som leaves, respectively. The compounds were further confirmed by gas chromatography-mass spectroscopy (GC-MS) and nuclear magnetic resonance (NMR) analysis. Methyl isoeugenol is a yellow colored compound, which resembles the color of the muga fiber and may be responsible for coloration of the same. It is anticipated that isoeugenyl acetate (also known as isoeugenol acetate), a phenylpropanoid compound present in the host plant might be converted to methyl isoeugenol during the course of metabolism in the silkworm larva, which in turn may be responsible for production of golden yellow colored silk fiber for building the cocoons. The present investigation might help to utilize methyl isoeugenol as a potential dyeing material for other fabrics in the industry thus providing a new dimension into the textile field.

摘要

研究了有机萃取法提取柞蚕茧色素的工艺. 采用正己烷和乙酸乙酯两种温和溶剂对木瓜茧纤维及其寄主植物木瓜叶进行了化学提取. 薄层色谱法（TLC）分别检测了蚕茧纤维和SOM叶提取物中的甲基异丁烯醇和乙酸异丁烯酯. 通过气相色谱-质谱（GC-MS）和核磁共振（NMR）分析进一步证实了化合物. 甲基异丁烯醇是一种黄色化合物，它类似于木瓜纤维的颜色，可能与木瓜纤维的颜色有关. 在家蚕幼虫的代谢过程中，寄主植物中的一种苯丙烷类化合物乙酸异丁烯（也称为乙酸异丁烯）可能被转化为甲基异丁烯醇，而甲基异丁烯醇又可能负责生产金黄色的蚕丝纤维，用于结茧. 本研究可能有助于利用甲基异丁烯醇作为工业上其他织物的潜在染色材料，从而为纺织领域提供一个新的视角.

KEYWORDS:

• Antheraea assamensis
• Machilus bombycina
• methyl isoeugenol
• isoeugenyl acetate
• phenylpropanoid

关键词:

• 阿萨门斯花药
• 孟买马基鲁斯
• 甲基异丁烯醇
• 乙酸异丁烯基酯
• 苯丙酸

Acknowledgments

The authors gratefully acknowledge the financial support from the Department of Biotechnology-Research Associateship Program in Biotechnology and Life Sciences, Govt. of India and the Department of Science and Technology, Ministry of Science and Technology, Govt. of India. The authors are also thankful to the DBT-RA supervisor Dr. P. J. Das for his supervision and the Director, ICAR-NRCP and Director, IASST, Assam, India for granting permission to avail the facilities to carry out the research.

Additional information

Funding

This work was supported by the Department of Biotechnology- Research Associateship Program in Biotechnology and Life Sciences, Govt. of India [file number 356/NRCP/2018-19/DBT-RA-I Project]. Department of Science and Technology, Ministry of Science and Technology, Govt. of India [grant number IASST/PF/2012-13/2145-2153].