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Context: Hyptis suaveolens (Linn.) Poit., Hyptis rhomboidea Mart. et Gal., and Hyptis brevipes Poit., are three species of Hyptis Jacq. (Lamiaceae). Hyptis suaveolens is used for the treatment of fever, headache, gastrointestinal bloating and rheumatism in the traditional folk medicine; Hyptis rhomboidea for hepatitis, ulcer and swollen poison; and Hyptis brevipes for asthma and malaria. Objective: To characterize chemical compositions of the oils from three Hyptis species and evaluate their potential antimicrobial, radical scavenging activities and toxicities against brine shrimp. Materials and methods: The oils were obtained by hydrodistillation, and their chemical compositions were investigated by gas chromatography-mass spectrometry (GC-MS). Minimum inhibitory concentrations (MICs) were determined using the tube double-dilution technique. The antioxidant activities were investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and toxicities by the brine shrimp bioassay. Results: Forty-seven, 33 and 28 constituents of oils isolated, respectively, from H. suaveolens, H. rhomboidea and H. brevipes were identified. Among the essential oils, the strongest antioxidant activity was exhibited by H. brevipes with an SC 50 value of 2.019 AE 0.25 mg mL À1. The H. brevipes oil exhibited the strongest antimicrobial activity (3.125-6.25 mg mL À1) on pathogens employed in the assay. They all showed significant toxicities with median lethal concentration (LC 50 ) values of 62.2 AE 3.07 mg mL À1, 65.9 AE 6.55 mg mL À1 and 60.8 AE 9.04 mg mL À1, respectively. Discussion and conclusions: The three Hyptis species oils possess strong antimicrobial activities and toxicities. Hyptis rhomboidea and H. brevipes showed considerable antioxidant activity compared to the positive control.

Two new (1 and 2) and 14 known (3−16) ingenane diterpenoids were isolated from the roots of Euphorbia ebracteolata by bioassay-guided fractionation together with UPLC-MS n analysis. The absolute configurations of the new diterpenoids were established from electronic circular dichroism (ECD) data and ECD calculations. Except for ingenol (16), the ingenane diterpenoids with long aliphatic chain substituents (1−15) exhibited potent activities against HIV-1, with IC 50 values of 0.7 to 9.7 nM and selectivity index values of 96.2 to 20 263. From the results, it was concluded that long aliphatic chain substituents are required for the enhanced anti-HIV activity of ingenane diterpenoids.

The genus of Murraya L. belonging to the family Rutaceae of the Rutales is a kind of ornamental bush or small macrophanerophytes which contains 12 species and is widely distributed in southern Asia and northeastern Australia 1 . Murraya exotica (M. exotica) is the model of the family and the leaves of this plant called curry leaf are known as a kind of condiment which has been used popularly in Indian cooking 2 . It is reported that M. exotica has also played an important role in folk medicine in eastern Asia and Australia, where it is used to cure indigestion, vomit and relieve nausea 3 . According to Li et al. 4 , essential oil of M. exotica show definite toxicity against S. zeamais, T. castaneum adults and Calletotrichum musae. However, the study on its anti-pathogenic bacteria was absolute a gap. For this reason, this work reported here was urgently needed for searching natural germifuga and antioxidant. EXPERIMENTALThe fresh leaves of M. exotica were collected from Hainan province, China. The leaves were washed gently and dried in the sky. The dried samples were powdered with a blender and passed through an 80-mesh sieve and placed in bags and