Characterization of the nonpolar and polar extractable components of glanded cottonseed for its valorization

Authors: He, Zhongqi; Nam, Sunghyun; LIU, SHASHA - University Of Science And Technology Beijing; ZHAO, QI - Tulane University

Submitted to: Molecules
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/16/2023
Publication Date: 5/19/2023
Citation: He, Z., Nam, S., Liu, S., Zhao, Q. 2023. Characterization of the nonpolar and polar extractable components of glanded cottonseed for its valorization. Molecules. 28(10). Article 4181. https://doi.org/10.3390/molecules28104181
DOI: https://doi.org/10.3390/molecules28104181

Interpretive Summary: Whereas cottonseed is a natural resource of agrochemicals (e. g., fiber, proteins, carbohy-drates, and lipids), its nutritional values are hindered by the presence of a toxic chemical (i.e., gossypol) in the conventional glanded (Gd) cottonseed. The current strategies of valorization of Gd cottonseed include formulation of biobased materials for nonfood applications, and exploration of its bioactive components as nutritive and health supplements. While these bioactive components are assumed to be peptide fragments, poly-phenolics, and/or flavonoids, the specific functional groups or compounds are yet to be identified. Therefore, this work characterized the nonpolar and polar fractions of Gd cottonseed for profiling the chemical composition of the Gd cottonseed. Results from this work confirmed and/or identified the major nutrient and functional carbon (C) components in Gd cottonseed. Potential bioactive capability of selectively identified compounds were observed through literature comparison. Those bioactive component candidates for future valorization research were highlighted.

Technical Abstract: Cottonseed is the second product of cotton (Gossypium spp.) crops after the major product fiber. Thus, characterization and valorization of cottonseed are an important part of cotton utilization research. In this work, the nonpolar and polar fractions of glanded (Gd) cottonseed were sequen-tially extracted by 100% hexane and 80% ethanol aqueous solution, and subjected to 13C and 1H nuclear magnetic resonance (NMR) spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), respectively. The nonpolar extracts showed the characteristic NMR peak features of edible plant oils with the absence of '-3 linolenic acid. Quantitative analysis revealed the percentage of polyunsaturated, monounsaturated and saturated fatty acids as 48.7%, 16.9% and 34.4%, respectively. Both general unsaturated fatty acid features and some specific olefinic compounds (e. g., oleic, linolenic, and gondonic acids) were found in the nonpolar (crude oil) fraction. In the polar extracts FT-ICR MS detected 1673 formulas with about 1/3 as potential phenolic compounds. Both total and phenolic formulas fell mainly in the categories of lipid, peptide-like, carbohydrate, and lignin. Some of these formulas were further identified as potential bioactive compounds through literature search and comparison. For example, one compound [2,5-dihydroxy-N'-(2,3,4-trihydroxybenzylidene) benzohydrazide] identified in the polar extracts is likely responsible for the anticancer function observed when used on human breast cancer cell lines. The chemical profile of the polar extracts provides a formulary for exploration of bioactive component candidates derived from cottonseed for nutritive, health and medical applications.