Guaiane-Type Sesquiterpenes from Curcuma phaeocaulis and Their Inhibitory Effects on Nitric Oxide Production

Abstract

Ten new guaiane-type sesquiterpenes (1-10), phaeocaulisins A-J, and 18 known guaiane derivatives were isolated from rhizomes of Curcuma phaeocaulis. Their structures were established on the basis of extensive spectroscopic analyses, X-ray crystallographic analysis, and comparison with literature data. Compound 10 is the first example of a norsesquiterpene with this unusual skeleton isolated from the genus Curcuma. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. Compounds 1, 2, 20, and 22-24 inhibited nitric oxide production with IC50 values less than 2 μM. Preliminary structure-activity relationships for these compounds are discussed.

Nutritional value, phytochemical composition, and biological activities of edibleCurcumaspecies: A review

“…[79,80] Rhizome extracts of C. phaeocaulis have been reported to exhibit inhibitory effects on nitric oxide production and phytochemical analysis of the rhizome extracts revealed the presence of guaiane-type sesquiterpenes, germacrane-type sesquiterpenoid, salvialane-type sesquiterpene, γ-elemene-type sesquiterpenes, eudesmane-type sesquiterpene, cyclic diarylheptanoid, and cadinane-type sesquiterpenes. [18,[81][82][83][84] Likewise, germacron has been identified as the main constituent present in the rhizome extracts of C. pierreana that showed inhibitory effect on the growth of microorganisms including Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus faecalis, and the fungus Candida albicans. [85] Germacrone has also been identified as the active principle responsible for the anti-inflammatory and analgesic activities Furanodiene, furanodienone, zederone, curzerenone, curzeone, germacrone, 13-hydroxygermacrone, dehydrocurdione, curcumenone, zedoaronediol, 13-hydroxycurzerenone, 1-oxocurzerenone, curcolone, procurcumenol, ermanin, curcumin, mixture of stigmast-4-en-3,6-dione and stigmasta-4,22-dien-3,6-dione, and mixture of 6ß-hydroxystigmast-4-en-3-one and 6ß-hydroxystigmasta-4,22-dien-3-one [150,151] of C. xanthorrhiza by Ozaki.…”

Sesquiterpenoids from the Rhizomes of <i>Curcuma phaeocaulis</i> and Their Inhibitory Effects on LPS-Induced TLR4 Activation

“…This extract was progressively fractionated with EtOAc, n-BuOH, and H 2 O, and the EtOAc-soluble fraction was subjected to various chromatographic experiments, which allowed us to isolate new guaianetype (2, 6), and furanogermacrane-type (11) sesquiterpenoids, as well as twelve known compounds: procurcumenol (1), 14) procurcumadiol (3), 14) zedoarondiol (4), 15) phaeocaulisine E (5), 7) wenyujinin L (7), 16) phacadinane B (8), 17) curcumenolactone A (9), 6) curcumenolactone B (10), 6) zedoarofuran (12), 18) curcolonol (13), 8) 4α-hydroxy-8,12-epoxyeudesma-7,11-diene-1,6-dione (14), 19,20) and neolitacumone A (15) 21) (Fig. 1).…”

“…Compound 6 was obtained as a yellow syrup, and its molecular formula of C 14 7) but differed due to the absence of one methyl group and one hydroxy group. This conclusion was further supported by the HMBC correlations between H-6 and C-5, C-8, and C-11; between the other olefinic proton H-9 and C-1, C-7, and C-14; and between the ethyl group (H 2 -11, H 3 -12) and C-7.…”

“…2) This plant has continually attracted attention from numerous scientists due to its various pharmacological activities, which include antiinflammatory, 3) antioxidative, 4) antitumor, 5) and hepatoprotective effects. 6) Prior phytochemical studies 4,7) have indicated that C. phaeocaulis contains diverse sesquiterpenoids and diarylheptanoids that contribute to the pharmacological effects of its rhizomes. 7,8) Toll-like receptors (TLRs) have important functions in the innate immune system, which is responsible for eliminating infectious microorganisms, including bacteria, fungi, protozoa, and viruses.…”

“…6) Prior phytochemical studies 4,7) have indicated that C. phaeocaulis contains diverse sesquiterpenoids and diarylheptanoids that contribute to the pharmacological effects of its rhizomes. 7,8) Toll-like receptors (TLRs) have important functions in the innate immune system, which is responsible for eliminating infectious microorganisms, including bacteria, fungi, protozoa, and viruses. 9,10) However, unregulated TLR stimulation is a pathogenic mechanism of autoimmune 11 and inflammatory diseases.…”