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Panax quinquefolium (American Ginseng) and Physostigma venenosum (Calabar Bean)
Published in Azamal Husen, Herbs, Shrubs, and Trees of Potential Medicinal Benefits, 2022
Sushweta Mahalanobish, Noyel Ghosh, Parames C. Sil
The bioactive compounds that are present in AG and exert various beneficial effects on human health are known to be ginsenosides or panaxosides. They are basically glycosides in nature consisting of sugar chain along with non-sugar (aglycone) moiety. The chemical structure of ginsenosides contains three types of aglycone – dammarane-type tetracyclic triterpene, pentacyclic oleanolic acid, and tetracyclic ocotillol type. The sugar part of ginsenosides comprises hexoses (glucose, galactose), 6-deoxyhexoses (furanose, rhamnose), pentoses (arabinose, xylose), and uronic acids (glucuronic acid). They are cyclic in nature and connected with aglycone part by hemiacetal bonds (Kochan et al., 2017; Nag et al., 2012). The nomenclature of ginsenosides is designed as “Rx”, where “R” indicates root and “x” indicates the polarity of the molecule in alphabetical order from “a” to “h” index.
Characterization of Phyto-Constituents
Published in Rohit Dutt, Anil K. Sharma, Raj K. Keservani, Vandana Garg, Promising Drug Molecules of Natural Origin, 2020
Himangini, Faizana Fayaz, Anjali
Glycosides are blends containing starch and a non-sugar development in a comparable molecule. Glycosides are characterized as the buildup results of sugars (counting polysaccharides) with a large group of various assortments of natural hydroxy (once in a while thiol) compounds (constantly monohydrate in character), in such a way, that the hemiacetal moiety of the starch must participate in the buildup. The carbohydrate or glycone is appended by an acetal linkage at carbon particle 1 to a nonsugar buildup or aglycone. On the basis of its pharmacological activity, sugar component and chemical property of aglycon component, glycosides are classified. Examples include cardiac glycosides (like digitalis acts on the heart), anthracene glycosides (like aloe and rhubarb used as purgative, and for treatment of skin diseases), chalcone glycoside (anticancer), alcoholic glycosides (salicin used as analgesic), cyanogenic glycosides (like amygdalin, prunasin) are used as flavoring agents in many pharmaceutical preparations. Amygdalin as shown in Figure 3.3 has been also utilized as antimalignant agent (HCN which is evolved in gastro kills cancer cells), and also as a cough suppressant in various preparations (Abraham et al., 2016). Overdose of cyanogenic glycosides can be lethal.
Inflammation
Published in George Feuer, Felix A. de la Iglesia, Molecular Biochemistry of Human Disease, 2020
George Feuer, Felix A. de la Iglesia
During this process, O2-requiring cyclooxygenase or lipoxygenase produce potent peroxy acids47 (Figure 16), and in some tissues, including the lung and platelets, prostaglandins are transformed to nonprostaglandin products. One of these is a labile hemiacetal derivative thromboxane A which can be further converted to thromboxane B.335 A biochemical characteristic of prostaglandins and other arachidonic acid-derived mediators is rapid catabolism. Many arachidonic acid derivatives arise by β- or ω-oxidation and reduction, and the distribution of these metabolic products shows variations among species. The catabolism is especially active in the lungs, and prostaglandins and their derivatives entering the bloodstream are removed by simple transport process through the lungs.
Green synthesis of metallic nanoparticles using pectin as a reducing agent: a systematic review of the biological activities
Published in Pharmaceutical Biology, 2021
Kogilavanee Devasvaran, Vuanghao Lim
The RG-I region makes up approximately 20–35% of pectin and is composed of arabinan and galactan side chains, which contain hydroxyl groups (Mohnen 2008; Hileuskaya et al. 2020). Due to the shift of the tautomeric equilibrium (cyclo-oxo-tautomerism), the free hemiacetal hydroxyl groups may be converted to free aldehyde groups in an alkaline medium. The reducing properties of pectin macromolecules are provided by these aldehyde groups (Hileuskaya et al. 2020). Thus, RG-1 reduces metal salts to metal nanoparticles (Figure 2), enabling pectin to reduce metallic nanoparticles (MNPs) and form pectin metallic nanoparticles (Pe-MNPs). The RG-II region, however, is the most complex and is made up of some of the rarest moieties, such as 3-deoxy-d-lyxo-2-heptulosaric acid (DHA), 3-deoxy-d-manno-2-octulosonic acid (Kdo), aceric acid, fucose, and apiose (Tan et al. 2018). This region has contributed to several studies, including mitogenic activity and immune complexes clearance enhancing activity (Shin et al. 1997; Sakurai et al. 1999).
Synthesis, antiasthmatic, and insecticidal/antifungal activities of allosamidins
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Gangliang Huang, Hualiang Huang
To synthesize α-trichloroacetimidate donor 8 (Scheme 3), the preparation of α-D-allosamine-hydrochloride 11 was carried out53. Compound 11 was treated with benzyloxycarbonyl (Cbz)-Cl and NaHCO3/H2O, N-benzyloxycarbonyl protected allosamine 12 in 85% yield was obtained. Compound 12 was acetylated in pyridine to obtain the α/β isomer (4:1) mixture of tetraacetate 13. The anomeric acetyl group was selectively removed in N,N-Dimethylformamide (DMF) with hydrazine acetate to obtain the hemiacetal 14. In the presence of 1,8-diaza[5.4.0]bicycloundec-7-ene (DBU), the compound 14 was reacted with the CCl3CN to obtain 82% yield of α-trichloroacetimidate donor 8.
Process optimisation, biocompatibility and anti-cancer efficacy of curcumin loaded gelatine microparticles cross-linked with dialdeyhde carboxymethyl cellulose
Published in Journal of Microencapsulation, 2019
Zeynep Kocer, Basak Aru, Umran Aydemir Sezer, Gulderen Yanıkkaya Demirel, Ulker Beker, Serdar Sezer
We employed FTIR spectrophotometry for the characterisation of DCMC. Figure 1(a) shows the reaction scheme of DCMC synthesis while Figure 1(b) shows the FTIR spectra. The bands at ∼1732 and ∼892 cm−1 reveal two properties of IR bands in DCMC (Mu et al. 2012). The absorbance around 1740–1720 cm−1 is generally the characteristic range of aldehyde carbonyl groups and the band at 880 cm−1 indicates the formation of hemiacetal bonds. The results indicate the existence of aldehyde groups due to the treatment of CMC with periodate oxidation (Mu et al. 2012).