Characterization of diarylheptanoids: An emerging class of bioactive natural products

Abstract

Diarylheptanoids are a class of secondary plant metabolites with a wide variety of bioactivity. Research on their phytochemistry and phytoanalysis is rapidly growing and the number of identified structures bearing the aryl-C-aryl skeleton is at present approaching 500. Historically, the yellow pigment curcumin has been characterized as the first diarylheptanoid and the extensive research on naturally occurring analogues is still ongoing. In this review, studies dealing with the characterization of linear and cyclic derivatives are discussed from the phytoanalytical point of view. Isolation, fractionation and purification strategies from natural sources along with their chromatographic behavior and structural characteristics are discussed. The role of various techniques used for the extraction (such as Soxhlet extraction, sonication, maceration/percolation, microwave-assisted extraction, supercritical carbon dioxide extraction); isolation (liquid-liquid extraction, column chromatographic techniques, preparative thin-layer and high-performance liquid chromatography, centrifugal partition chromatography, counter-current chromatography); separation (thin-layer chromatography, high-performance liquid chromatography, gas chromatography, capillary electrophoresis) and structural characterization (UV/Vis spectroscopy, infrared spectroscopy, X-ray crystallography, mass spectrometry, nuclear magnetic resonance spectroscopy and circular dichroism spectroscopy) are critically reviewed.

Diarylheptanoids as nutraceutical: A review

“…They are structurally diverse and have been isolated from seeds, fruits, leaves, roots, rhizomes and barks of plants of different families such as Myricaceae, Betulaceae, Zingiberaceae, Aceraceae, Leguminosae and Burseraceae (Per et al, 2002;Kawai et al, 2008;Ibrahim et al, 2017). More than 400 diarylheptanoids have been identified till now and most compounds occur in Zingiber, Betula and Alnus species (Vidaković et al, 2017;Alberti et al, 2018). These species exhibit characteristic aroma, and also act as colouring agents.…”

α-Tetralonyl Glucosides from the Green Walnut Husks of Juglans mandshurica and Their Antiproliferative Effects

“…Diarylheptanoid is a group of compounds that bears the 1,7-dihenylheptane skeleton as a special characteristic in the natural product estate [16]. Since the first diarylheptanoid isolated in 1815, approximately 400 such materials have been obtained from natural resources [17]. Hirsutanone and oregonin, from Alnus japonica Steud, exhibited potent antiproliferative activity against two colon cancer cell lines (HCT-15 and Colo205) [18].…”

Analytical Methods of Isolation and Identification

“…Compared with other conventional separation methods, SFE possesses the following advantages: (1) No residual organic solvents, fast extraction speed, simple process, high yield, and easy operation; (2) of SF are easy to improve, only the pressure needs to be changed at a certain temperature; (4) entrainers can be added to change the polarity of the extraction medium to extract polar substances; extraction medium can be recycled with low cost; (5) it could be applied combined with other chromatographic techniques, such as GC, IR, GC-MS, and HPLC, to extract, separate, and determine phytochemicals efficiently and quickly, so as to achieve the integration of extraction and quality analysis. However, supercritical extraction has some limitations: strong solubility of fat-soluble components, weak solubility of water-soluble components, high cost of equipment, resulting in higher product costs, and cleaning equipment is difficult.…”

“…Classical isolation methods, including solvent extraction, precipitation, crystallization, fractional distillation, salting-out, and dialysis, are still used commonly at present. On the other hand, modern separation technologies such as column chromatography, high performance liquid chromatography, ultrafiltration, and high performance liquid drop countercurrent chromatography also play an important role in the separation of phytochemicals [1][2][3].…”