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Exploring Important Herbs, Shrubs, and Trees for Their Traditional Knowledge, Chemical Derivatives, and Potential Benefits
Published in Azamal Husen, Herbs, Shrubs, and Trees of Potential Medicinal Benefits, 2022
Tilahun Belayneh Asfaw, Tarekegn Berhanu Esho, Archana Bachheti, Rakesh Kumar Bachheti, D.P. Pandey, Azamal Husen
Phenylpropanoids are one of the largest secondary metabolites produced by plants and are classified under polyphenolics. These large classes of bioactive compounds are derived from aromatic amino acids (like phenylalanine) in most plant species (Figure 1.12). Phenylpropanoids (based on their biosynthesis as shown in Figure 1.12) include flavonoids, phenolic acids, stilbenes, coumarins, and monolignols, which can be found in medicinal plants and plant foods (Deng and Lu, 2017). Phenylpropanoids play an important role in the treatments of cancer, stress, having antioxidant, antiviral, and antifungal activities. Resveratrol, flavanonol, coumarin, anthocyanidin, umbelliferone, p-hydroxybenzoic acid, flavonol, flavanone, protocatechuic acid, caffeic acid and sinapic acid, coniferyl alcohol, p-coumaryl alcohol, and sinapyl alcohol are included in this classification.The systematic classifications of phenylpropanoids and its chemical.
Nutraceuticals and Functional Foods
Published in Robert E.C. Wildman, Richard S. Bruno, Handbook of Nutraceuticals and Functional Foods, 2019
From trans-cinnamic acid, several simple phenolic compounds can be made. These include the benzoic acid derivatives vanillin and salicylic acid (Figure 1.8). Also, trans-cinnamic acid can be converted to para-coumaric acid. Simple phenolic derivatives of para-coumaric acid include caffeic acid and ferulic acid. CoA can be attached to para-coumaric acid to form para-coumaryl CoA. Both para-coumaric acid and para-coumaryl CoA can also be used to form lignin-building blocks, para-coumaryl alcohol, coniferyl alcohol, and sinapyl alcohol. After cellulose, lignin is the most abundant organic molecule in plants. To continue the formation of other phenolic classes, para-coumaryl CoA can undergo further enzymatic modification, involving three malonyl CoA molecules, to create polyphenolic molecules such as chalcones and then flavonones. The basic flavonone structure is then the precursor for the flavones, isoflavones, and flavonols. Also, flavonones can be used to make anthocyanins and tannins via dihydroflavonols (Figures 1.7, 1.9, and 1.10).
Plant Phenolics
Published in Ruth G. Alscher, John L. Hess, Antioxidants in Higher Plants, 2017
Consequently, lignins are viewed as heterogeneous polymers, and are deposited into cell walls during secondary thickening processes — this apparently being initiated at the cell corners and middle lamella, then extending into the secondary wall (see Lewis and Yamamoto17 and Davin and Lewis49). Radiotracer experiments, coupled with microautoradiography, suggest that p-coumaryl alcohol 36 is predominantly deposited during early lignification stages, and is then followed by coniferyl alcohol 37; in angiosperms, a similar trend occurs, except that sinapyl alcohol 38 appears to be deposited during the latter stages of lignin formation.81 While observations of this type are beginning to provide an explanation for the basis of lignin heterogeneity, they raise fascinating questions as to how this process is regulated and controlled, e.g., (1) how are the individual monolignol moieties temporally and spatially transported across the plasma membrane and into the lignifying cell walls? and (2) what is the relative importance of E- and Z-monolignols? (It must be emphasized that while much is known about the enzymology of monolignol formation, our understanding of the actual process of lignification is poorly understood.)
The metabolic effect of gut microbiota on drugs
Published in Drug Metabolism Reviews, 2020
Yuan Xie, Fangdi Hu, Dawei Xiang, Hui Lu, Wenbin Li, Anpeng Zhao, Longji Huang, Rong Wang
Syringin, a glucoside present in many plants, such as Acanthopanax sp. and bark of lilac, could be metabolized to sinapyl alcohol by human fecal suspensions. In addition to cytotoxic effects on several tumor cell types, sinapyl alcohol exhibits greater effects than syringin on suppression of increased vascular permeability induced by acetic acid and acute paw edema induced by carrageenan in vivo and inhibition of LPS-induced production of NO, prostaglandin E2, and TNF-a in vitro. Besides, when analgesic activity was measured using the acetic acid-induced writhing test and the hot pot plate test, sinapyl alcohol was much more potent than syringin (Choi et al. 2004).