In vitro antioxidant, anticholinesterases, anti-α-amylase, and anti-α-glucosidase effects of Algerian Salvia aegyptiaca and Salvia verbenaca.

In this study, Salvia aegyptiaca and Salvia verbenaca aerial part decoction and methanol extracts (SAE DE, SAE ME, SVR DE, and SVR ME) were screened for their in vitro antioxidant, anti-Alzheimer, and antidiabetic enzymes inhibition activities. The antioxidant properties of Salvia extracts were determined using DPPH radical scavenging, ABTS radical scavenging, Alkaline DMSO superoxide radical scavenging, ß-carotene bleaching, reducing power, and metal chelating activity assays. All extracts showed high antioxidant capacity and the antioxidant properties with the best performance were detected in the SAE ME and SVR ME. The extracts of S. aegyptiaca and S. verbenaca showed a low inhibitory activity of acetylcholinesterase (AChE), whereas, the methanol extract of S. aegyptiaca had the highest inhibitory activity on butyrylcholinesterase (BChE) (71.60 ± 4.33% for 100 µg/ml) compared to the other extracts. In vitro inhibitory effect on diabetic enzymes showed that the ME inhibited α-amylase enzyme with an IC50 86 and 101 µg/ml for SAE and SVR, respectively. Similarly, both extracts inhibited α-glucosidase with (IC50 97 and 150 µg/ml, respectively). The decoction extracts exhibited lower activity on both enzymes. PRACTICAL APPLICATIONS: It is becoming evident that oxidative stress is involved in several acute and chronic diseases. Counteracting free radical generation has become one of the widest fields of research worldwide. This study deals with the in vitro antioxidant activity of two plants from the Salvia genus as well as the assessment of their in vitro inhibitory properties of four key enzymes implicated in diabetes and Alzheimer's disease. Concerning the practical applications of our work, it can be explored in its antioxidant part as a food supplement to prevent the excess of free radicals in the body and also in other industrial practices. Another potential use is in the prevention and amelioration of both diabetes and Alzheimer's disease symptoms for the extracts that had enzyme inhibitory activity, but this deserves further toxicological and in vivo studies.

Antiangiogenic Iridoids from Stachys ocymastrum and Premna resinosa.

In this paper, the isolation of one new iridoid glucoside, 6ß-acetoxyipolamiide (1: ), and thirteen (2:  - 14: ) known congeners from two Lamiaceae species, Stachys ocymastrum and Premna resinosa, leaf extracts is reported. The structural determination of the isolated compounds was performed by mono- and bidimensional NMR spectroscopic analysis as well as MS experiments. The isolates were assayed for their antiangiogenic activity by two in vivo models, zebrafish embryos and chick chorioallantoic membrane assays. The compounds with a significant antiangiogenic activity in both assays were ß-hydroxyipolamiide (2: ), ipolamiide (3: ), and buddlejoside A5 (8: ). 6-O-α-l-(3″-O-p-Methoxycinnamoyl-4″-O-acetyl)rhamnopyranosyl catalpol (13: ) and 6-O-α-l-(2″-trans-caffeoyl)rhamnopyranosyl catalpol (6: ) showed the best antiangiogenic response on blood vessel growth in zebrafish embryos, whereas saccatoside (10: ) and 6-O-α-l-(2″-O - : p-methoxycinnamoyl-3″-O-acetyl)rhamnopyranosyl catalpol (14: ) resulted in a strong reduction of capillary formation in the chorioallantoic membrane assay.

Anti-angiogenic activity of iridoids from Galium tunetanum

ABSTRACT The phytochemical study of Galium tunetanum Lam., Rubiaceae, leaves led to the isolation of 13 compounds from the chloroform-methanol and the methanol extracts, including six iridoid glycosides, one non-glycoside iridoid, two p-coumaroyl iridoid glycosides, two phenolic acids, and two flavonoid glycosides. The structural determination of the isolated compounds was performed by mono- and bidimensional NMR spectroscopic data, as well as ESI-MS experiments. All compounds were isolated from this species for the first time. The anti-angiogenic effects of the isolated iridoids were also reported on new blood vessels formation using the chick embryo chorioallantoic membrane as in vivo model. Results showed that among the isolated iridoids tested at the dose of 2 µg/egg, asperuloside (1), geniposidic acid (2), and iridoid V1 (3) reduced microvessel formation of the chorioallantoic membrane on morphological observations using a stereomicroscope. The anti-angiogenic effects of the active compounds, expressed as percentages of inhibition versus control, were 67% (1), 59% (2), and 54% (3), respectively. In addition, the active compounds were able to inhibit angiogenesis in the chorioallantoic membrane assay, in a dose-dependent manner (0.5-2 µg/egg) as compared to the standard retinoic acid.