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Bioassay-guided separation of acetone extract from lichen Parmotrema tinctorum (Delise ex Nyl.) Hale led to the isolation of six major phenolic constituents (1–6). Compounds structures were established using NMR and mass spectral techniques. Further, to develop libraries on these scaffolds, a series of semi-synthetic derivatives were prepared (1a–1f, 2a–2b, 3a, 5a) and investigated for their free-radicals (2,2-diphenyl-1-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS)) scavenging and advanced glycation end products (AGEs) formation inhibitory activities. Amongst tested derivatives, 1a, 1d, 1e, 2a, and 5a showed strong ABTS scavenging potentials comparable to Trolox. In addition, these derivatives also manifested moderate AGEs formation inhibitory activities. [ABSTRACT FROM AUTHOR]

High starch and carbohydrate content in rice (Oryza sativa Linn.) disparages this food responsible for postprandial hyperglycemic excursions. However, rice is an Asian food synonym. Additionally, in traditional Indian healing practices, rice is used for treatment of various disorders. In this research, we analyzed micronutrient and phytochemical contents in different rice samples available in market. Effect of aqueous-ethanol extract of each type of rice was evaluated against intestinal α-glucosidase to examine extract's influence on carbohydrate digestion. Free-radicals scavenging activities as a measure of antioxidant potential in different rice were also examined. Brown-rice presented highest (54%) α-glucosidase inhibition followed by parboiled-rice (52%), idly-rice (48%), hand-pounded rice (42%), dosa-rice (40%) and basmati-rice (39%). Polished white sona-masoori rice presented least enzyme inhibitory (31%) activity. Presence of higher α-glucosidase inhibitory activity was regarded as slow digesting rice that would impart lesser postprandial glycemic excursion. Brown and parboiled-rice presented highest ABTS֗+ radical scavenging (74%) activity whereas; idly-rice displayed highest DPPH scavenging (50%) activity. Higher polyphenol and niacin contents in rice were found significantly (p<0.0001 and p<0.01 respectively) correlated with enzyme inhibitory activity. Higher polyphenol content was found responsible for enhanced free-radicals scavenging activity. Increasing concentrations of niacin and pantothenic acid correlated with ABTS֗+ radical scavenging activity. [ABSTRACT FROM AUTHOR]

Abstract: A bioassay-guided fractionation and chemical investigation of the stem bark of Premna tomentosa resulted in the isolation and characterization of four new icetexane diterpenes (1–4), along with the known compounds coniferaldehyde (5), syringaldehyde (6), lupeol (7), betulin (8), and 2-(4-methoxyphenyl)-2-butanone (9). Their structures were established on the basis of extensive spectroscopic (IR, MS, 2D NMR) data analysis and by comparison with the spectroscopic data reported in the literature. The new compounds exhibited diverse functionalities on a common icetexane diterpene skeleton. In addition, cytotoxic activities of the icetexanes (1–3) were evaluated by determining their inhibitory effects on the human cancer cell lines (MCF-7, HT-29, Hep-G2, A-431, and A-549). Compounds 1 and 3 showed selective inhibitory activity against MCF-7 (15.96μg/mL and 15.84μg/mL) and HT-29 cell lines (16.21μg/mL and 14.57μg/mL), respectively. [Copyright &y& Elsevier]

Abstract: The phytochemical investigation of the hexane extract of the Hedychium coronarium led to the isolation and identification of two new labdane diterpenes (1 and 2) along with 10 known metabolites (3–12). The structures of the new compounds were established on the basis of spectroscopic data analysis (1D and 2D NMR and MS). Cytotoxic activities of the isolates were studied against the A-549 (lung cancer), SK-N-SH (human neuroblastoma), MCF-7 (breast cancer) and HeLa (cervical cancer) cell lines. [ABSTRACT FROM AUTHOR]

A phytochemical study on the arial part of Caragana sukiensis resulted in the isolation of three new cycloartane triterpenoids 1 – 3 and their structures were fully established on the basis of detailed spectroscopic (especially 2D NMR and Mass) analysis. These new compounds possessed hemiacetal fused tetrahydropyran rings at C-15/C-16, while 2 and 3 also contains d -xylose moiety. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive reinvestigation of chemical constituents from the rhizomes of Hedychium spicatum led to the isolation of two new labdane-type diterpene (1, 2), together with six known compounds (3–8). Their structures were established on the basis of extensive spectroscopic (IR, MS, 2D NMR) data analysis and by comparison with the spectroscopic data reported in the literature. In addition, all the isolates were tested for their cytotoxicity against the THP-1 (human acute monocytic leukemia), HL-60 (human promyelocytic leukemia), A-375 (human malignant melanoma) and A-549 (human lung carcinoma) cancerous cell lines. [Copyright &y& Elsevier]

Abstract: Phytochemical investigation of antihyperglycemic extract of rhizomes of Hedychium spicatum led to the isolation of two new labdane type diterpenes 2, 3 along with seven known compounds (1, 4–9). Their structures were established on the basis of NMR (1D and 2D) and mass spectroscopic analysis. The new compound 2 displayed strong intestinal α-glucosidase inhibitory activity. Other compounds also displayed varying degree of intestinal α-glucosidase inhibitory potential. [Copyright &y& Elsevier]

Abstract: Phytochemical investigation of CHCl3 extract of the rhizomes of Hedychium spicatum led to the isolation of two new labdane-type diterpenes, compounds 1 and 2 along with five known compounds (3–7). Their structures were established on the basis of NMR (1D and 2D) and mass spectroscopic analysis. In addition, all the isolates were tested for their cytotoxicity against the Colo-205 (Colo-cancer), A-431 (skin cancer), MCF-7 (breast cancer), A-549 (lung cancer) and Chinese hamster ovary cells (CHO). Two new compounds 1 and 2 were shown good cytotoxic activity. [Copyright &y& Elsevier]

Three new cycloartane triterpenoids, sukienside A-C, are isolated from the aerial parts of Caragana sukiensis. [ABSTRACT FROM AUTHOR]