title: Biogenic guaianolide-type sesquiterpene lactones with antioxidative and anti-inflammatory properties from natural mangrove hybrid Rhizophora annamalayana.
abstract: Previously undescribed guaianolide-type sesquiterpene lactones were isolated from the chloroform fraction of the natural hybrid mangrove Rhizophora annamalayana, and were characterised as (Z)-3α,4,5,6-tetrahydro-5α-isobutyl-2β-(methoxymethyl)-7-methyl-3H-cyclohepta[b]carbolactone (1) and (7Z)-isopentyl 3α,4,5,6,7,8-hexahydro-2β-((E)-11-methylbut-10-enyl)-1-oxo-2H-cyclohepta[b]furan-6-carboxylate (2). Compound 2 displayed greater antioxidative activities {1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2'-azino-bis-3 ethylbenzothiozoline-6-sulphonic acid diammonium salt (ABTS), IC500.65 and 0.62 mg/mL, respectively)} compared to 1 (IC500.83 and 1.14 mg/mL, respectively) (p < 0.05). Compound 2 recorded no significant difference in DPPH.scavenging activities (IC500.65 mg/mL) compared to α-tocopherol (IC500.63 mg/mL). Pro-inflammatory 5-lipoxygenase inhibitory activity of 2 was found to be comparable (IC500.98 mg/mL) to that displayed by synthetic anti-inflammatory drug ibuprofen (IC500.93 mg/mL). Compound 2 showed significantly greater selectivity index (anti-cyclooxygenase-1/anti-cyclooxygenase-2 = 2.15) than non-steroidal anti-inflammatory ibuprofen (<0.5) (p < 0.05), and therefore, might be used as selective cyclooxygenase-2 inhibitor. The hitherto undescribed guaianolide lactones might be used as potential anti-inflammatory and antioxidative pharmacophore leads.
authors.affiliation: a ​Marine Bioprospecting Section of Marine Biotechnology Division , Central Marine Fisheries Research Institute , Cochin , India.
authors.forename: Vamshi Krishna
authors.initials: VK
authors.lastname: Raola
authors.affiliation: a ​Marine Bioprospecting Section of Marine Biotechnology Division , Central Marine Fisheries Research Institute , Cochin , India.
authors.forename: Kajal
authors.initials: K
authors.lastname: Chakraborty
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry* / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism; D051545:Cyclooxygenase 1 / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical / Q000379:methods; D020128:Inhibitory Concentration 50; D007783:Lactones / Q000737:chemistry / Q000494:pharmacology; D016859:Lipoxygenase Inhibitors / Q000737:chemistry / Q000494:pharmacology; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry; D043982:Rhizophoraceae / Q000737:chemistry*; D045789:Sesquiterpenes, Guaiane / Q000737:chemistry / Q000494:pharmacology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D052246:Cyclooxygenase 2 Inhibitors; D007783:Lactones; D016859:Lipoxygenase Inhibitors; D010936:Plant Extracts; D045789:Sesquiterpenes, Guaiane; D001094:Arachidonate 5-Lipoxygenase; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2
keywords: Natural mangrove hybrid; Rhizophora annamalayana; anti-inflammatory; anti-inflammatory selectivity index; antioxidative; guaianolide-type sesquiterpene lactones