Bioactive Constituents ofJuniperus turbinataGuss. from La Maddalena Archipelago

Abstract

A comprehensive phytochemical study of Juniperus turbinata (Cupressaceae) collected from La Maddalena Archipelago (Sardinia, Italy) is reported. Both the essential oil and the ethanolic extract obtained from the aerial parts were analyzed. The essential oil appears to belong to a new chemotype compared to other Mediterranean juniper accessions, as it was favored by geographic isolation of the isles. It showed a low content of monoterpene hydrocarbons and α-terpineol, ent-manoyl oxide, 1,10-di-epi-cubenol as the major constituents. The ethanolic fraction contained mainly diterpenoids. Among these, 15-formyloxyimbricatolic acid (7) is a new natural product since it has hitherto been obtained only by synthetic route. The phenolic fraction contained biflavonoids: cupressuflavone (9), followed by minor amounts of amentoflavone (10) and hinokiflavone (11). The essential oil and six purified compounds (1 - 4, 8 and 9) were assessed for biological activities, namely antioxidant (assessed by DPPH , ABTS and FRAP methods) and cytotoxic effects towards selected human tumor cell lines (MDA-MB 231, A375 and HCT116 cells). Compound 3 exhibited higher radical scavenging activity against ABTS radical than the reference Trolox. Noteworthy, compound 8 showed powerful effects towards tumor cell lines, with IC values in the range of 0.060 - 0.201 μm, which make it a promising anticancer drug candidate.

The Therapeutic Potential of Apigenin

“…In some cases the chemotaxonomic relevance has also been demonstrated. In gymnosperms, apigenin derivatives are mostly present in dimeric forms, with apigenin residues variously coupled, e.g., with C‒C linkage as in cupressuflavone and amentoflavone (I-8, II-8″ and I-3′, II-8″, respectively), or C‒O linkage (I-4′, II-6″) as in hinokiflavone (Figure 2) [24,25,26,27]. Biogenetically, apigenin is a product of the phenylpropanoid pathway and may be obtained from both phenylalanine and tyrosine, two shikimate-derived precursors.…”

The Current Status of the Pharmaceutical Potential of Juniperus L. Metabolites

“…Juniperus turbinata Guss.) ethanol extract showed the strongest cytotoxic activity (IC 50 values of 0.06, 0.114, and 0.201 μM on human colon cancer HCT116, human malignant melanoma A375, and human breast adenocarcinoma MDA-MB-231 cell lines, respectively), being several times more potent than the reference compound cisplatin (IC 50 values of 1.87 to 11.86 μM) [ 19 ] indicating that imbricataloic acid make a promising anticancer drug candidate.…”

“…Juniperus turbinata Guss.) exhibits cytotoxic effects against HCT116, A375, and MDA-MB-231 human tumor cell lines, in a concentration-dependent inhibitory effect with IC 50 values of 9.48–33.69 μg/mL [ 19 ]. Juniperus oxycedrus essential oil exhibited high antitrypanosomal activity (IC 50 of 0.9 μg/mL) against Trypanosoma brucei brucei , with no cytotoxic effects on RAW 267.4 macrophage cell line showing the highest selectivity index (63.4) [ 20 ].…”

Growth inhibitory activity of biflavonoids and diterpenoids from the leaves of the Libyan Juniperus phoenicea against human cancer cells

“…Cupressoflavone ( 1 ) was previously reported from Juniperus turbinate (Venditti et al, ), and it was shown to possess cytotoxic activity against the human cancer cell lines breast adenocarcinoma (MDA‐MB 231), malignant melanoma (A375), and colon carcinoma (HCT116), with IC 50 values of 16.1, 12.7, and 19.3 μM, respectively, after 72 hr incubation using the MTT assay. However, on the present study, compound 1 displayed a significant decrease in the percentage viability of lung cancer cells A549 at concentrations higher than 0.33 μM (Table ).…”