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The aim of this study was to isolate the phytoconstituents and evaluate the biological activities of Berberis hispanica. Three phenolic compounds (tamarixetin, caffeic acid and rutin) were isolated from B. hispanica. The structures of the pure compounds were elucidated by spectroscopic and mass-spectrometric analyses, including 1D-, 2D-NMR, and HPLC-TOF/MS. In addition, antimicrobial, anti-oxidant and anti-proliferative effects of the extracts, some fractions and isolated compounds were evaluated. The extracts of B. hispanica were evaluated against six bacterial strains and exhibited the highest activity against Klebsiella pneumonia (15 mm at 100 mg/mL). Fraction T36 (IC50<5 μg/ mL) from the n-butanol extract displayed higher radical scavenging activity than butylated hydroxytoluene. The isolated compounds were evaluated for their anti-proliferative effects against human cervical adenocarcinoma (HeLa) cell line by real time cell analyzer assay and tamarixetin exhibited the remarkable effect (IC50<50 μg/mL) on HeLa cells. This study supports the documented medicinal effects of B. hispanica. [ABSTRACT FROM AUTHOR]

Abstract: A formylated triterpene named cladocalol has been isolated from the leaves of Eucalyptus cladocalyx, together with ursulolactone acetate, ursolic acid, 3β-acetate-12,20(29)-lupadien-28-oic acid, β-sitosterol and the known flavonoid eucalyptine. Their structures were mainly established by extensive NMR studies (1H NMR, 13C NMR, DEPT, 1H–1H COSY, HSQC, HMBC) and mass spectroscopy as well as by X-ray crystallographic analysis. In this paper, we report on the cytotoxic effect induced by cladocalol and its derivatives on the myeloid leukemia cell line HL-60. [Copyright &y& Elsevier]

The aim of this study was to evaluate the total phenolic and flavonoid content, and the in vitro antioxidant, anti-inflammatory, antibacterial, antifungal, antimalarial, cytotoxicity, and antiprotozoal activities of the Algerian plant Cytisus villosus Pourr. (Syn. Cytisus triflorus L'Hérit.). Additionally, the radioligand displacement affinity on opioid and cannabinoid receptors was assessed for the extracts and isolated pure compounds. The hydro alcoholic extract of the aerial part of C. villosus was partitioned with chloroform (CHCl3), ethyl acetate (EtOAc), and n-butanol (n-BuOH). The phenolic content of the C. villosus extracts was evaluated using a modified Folin–Ciocalteau method. The total flavonoid content was measured spectrometrically using the aluminum chloride colorimetric assay. The known flavonoids genistein (1), chrysin (2), chrysin-7-O-β-d-glucopyranoside (3), and 2″-O-α-l-rhamnosylorientin (4) were isolated. The antioxidant activities of the extracts and isolated compounds were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DDPH) and cellular antioxidant activity (CAA) assays. The plant extracts showed moderate antioxidant activity. EtOAc and n-BuOH extracts showed moderate anti-inflammatory activity through the inhibition of induced nitric oxide synthase (iNOS) with IC50 values of 48 and 90 µg/mL, respectively. The isolated pure compounds 1 and 3 showed good inhibition of Inducible nitric oxide synthase (iNOS) with IC50 values of 9 and 20 µg/mL, respectively. Compounds 1 and 2 exhibited lower inhibition of Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) with IC50 values of 28 and 38 µg/mL, respectively. Furthermore, the extracts and isolated pure compounds have been shown to exhibit low affinity for cannabinoid and opioid receptors. Finally, n-BuOH extract was a potent inhibitor of Trypanosoma brucei with IC50 value of 7.99 µg/mL and IC90 value of 12.61 µg/mL. The extracts and isolated compounds showed no antimicrobial, antimalarial nor antileishmanial activities. No cytotoxic effect was observed on cancer cell lines. The results highlight this species as a promising source of anti-inflammatory and antitrypanosomal agents. [ABSTRACT FROM AUTHOR]

A new phloroglucinol derivative, identified as 3-benzoyl-3-hydroxy-5-(3-methylbut-2-en-1- yl)cyclopentane-1,2,4-trione (1), together with eight previously reported compounds, quercetin, myricitrin, hypericin, biapeginin, pseudohypericin, myricetin, 1,3,5,6-tetrahydroxyxanthone, and β-sitosterol were isolated from the chloroform, ethyl acetate and butanol extracts of the aerial part of Hypericum afrum (Lam.). Their structures were elucidated by spectroscopic analyses, including 1D-, 2D-NMR and HRESIMS. The EtOAc extract showed moderate MAO-A inhibition with an IC50 value of 3.35 μg/mL. Bioassay-guided fractionation of the EtOAc extract resulted in the isolation of quercetin as the active component exhibiting MAO-A inhibitory activity with an IC50 value of 1.25 μM. [ABSTRACT FROM AUTHOR]

The in vitro activity of L. donovani (promastigotes, axenic amastigotes and intracellular amastigotes in THP1 cells) and T. brucei, from the fractions obtained from the hydroalcoholic extract of the aerial part of Hypericum afrum and the isolated compounds, has been evaluated. The chloroform, ethyl acetate and n-butanol extracts showed significant antitrypanosomal activity towards T. brucei, with IC50 values of 12.35, 13.53 and 12.93 µg/mL and with IC90 values of 14.94, 19.31 and 18.67 µg/mL, respectively. The phytochemical investigation of the fractions led to the isolation and identification of quercetin (1), myricitrin (2), biapigenin (3), myricetin (4), hyperoside (5), myricetin-3-O-β-d-galactopyranoside (6) and myricetin-3'-O-β-d-glucopyranoside (7). Myricetin-3'-O-β-d-glucopyranoside (7) has been isolated for the first time from this genus. The chemical structures were elucidated by using comprehensive one- and two-dimensional nuclear magnetic resonance (1D and 2D NMR) spectroscopic data, as well as high-resolution electrospray ionization mass spectrometry (HR-ESI–MS). These compounds have also been evaluated for their antiprotozoal activity. Quercetin (1) and myricetin (4) showed noteworthy activity against T. brucei, with IC50 and IC90 values of 7.52 and 5.71 µM, and 9.76 and 7.97 µM, respectively. The T. brucei hexokinase (TbHK1) enzyme was further explored as a potential target of quercetin and myricetin, using molecular modeling studies. This proposed mechanism assists in the exploration of new candidates for novel antitrypanosomal drugs. [ABSTRACT FROM AUTHOR]