Chemical constituents of the essential oil from the leaves of Minthostachys mollis (Kunth) Griseb Vaught var. mollis collected in January 2008 at Tuñame, Trujillo State, Venezuela, were separated and identified by GC-MS analysis. The essential oil was obtained by hydrodistillation and thirteen components (98.5% of the sample) were identified by comparison with the Wiley GC-MS library data base. The two major components were pulegone (55.2%) and trans-menthone (31.5%). The essential oil showed a significant inhibitory effect against Gram-positive and Gram-negative bacteria, especially Bacillus subtilis and Salmonella typhi (4 μg/mL).

The essential oil obtained from the leaves of Lantana camara var. moritziana (Otto & Dietr.) López-Palacios collected at Rubio, Táchira State, Venezuela, was obtained by hydrodistillation in a Clevenger trap (0.1% yield). The oil was analyzed by gas chromatography-mass spectrometry (GC/MS) on HP GC-MS System, model 5973, identifying 33 compounds (97.1%) of which the major components were germacrene D (31.0%), followed by β-caryophyllene (14.8%), α-phellandrene (6.7%), limonene (5.7%) and 1,8-cineole (5.2%). Evaluation of the antibacterial activity by agar diffusion method with discs against international reference bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Salmonella Typhi, Pseudomonas aeruginosa) showed growing inhibition of E. faecalis and S. aureus at MIC of 350 mg/mL and 400 mg/mL, respectively.

Angiogenesis is involved in many physiological and pathological conditions. Natural compounds with antioxidant activity have also been reported to possess potent antiangiogenic properties by regulating angiogenesis modulators such as vascular endothelial growth factor (VEGF). Based on this, we screened the antioxidant and antiangiogenic activities of Astronium graveolens leaf extracts by a DPPH test and a competitive enzyme-linked immunosorbent assay, respectively. MeOH extract expressed a significant free radical-scavenging activity (EC₅₀ = 37.65 μg/mL) and it was able to inhibit the interaction between placental growth factor (PlGF) (placental growth factor), a VEGF family member, and its receptor Flt-1 by more than 50% at 1 mg/mL. 1,2,3,4,6-Penta-O-galloyl-d-glucopyranose, 6 is the most active compound of the extract. It exhibited a high potency in scavenging DPPH (EC₅₀ = 2.16 μg/mL) and reduced by 58% the PlGF/Flt-1 interaction at a concentration of 50 μM. Moreover, the known compounds (1-6) have been isolated for the first time in A. graveolens.

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Apis mellifera bees obtain propolis by adding wax and salivary secretions to resinous, gummy or balsamic materials collected from various plant sources. Its chemical composition depends on many factors (type of bee, flora accessed, environment, management, season, vegetation and geographical area of collection). In the hive, the bees use propolis to consolidate structural components, varnish inside the cells and prevent vibrations. Propolis is known for its antibacterial, fungicidal, antiviral, anesthetic, antiulcer, immunostimulating, hypotensive, cytostatic, and antioxidant properties, the essential oil of Apis mellifera propolis, collected in Falcon state, was obtained by hydrodistillation using a Clevenger trap (0.06% yield). The oil was analyzed by gas chromatography coupled to mass spectrometry (GC / MS) in an HP GC-MS System Model 5973. Twentythree compounds were identified (93.6%), of which the three major compounds were germacrene D (26.5%), βcaryophyllene (10.2%) and β-elemene (8.1%).