Chemical Composition, Antioxidant Properties, and Antibacterial Activity of Essential Oils of Satureja macrostema (Moc. and Sessé ex Benth.) Briq.

Satureja macrostema is a plant that is located in various regions of Mexico and is used in a traditional way against illness. Essential oils (EOs) were obtained from leaves Satureja macrostema and the chemical composition was evaluated by gas chromatography-mass spectrometry (GC-MS). The antioxidant effect of the oil was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and by Trolox Equivalent Antioxidant Capacity (TEAC). In vitro antibacterial activity against Escherichia coli and Staphylococcus aureus was determined using a broth microdilution assay and thin layer chromatography-direct bioautography (TLC-DB) to identify active antibacterial compounds. The EOs analysis showed 21 compounds, 99% terpenes, and 96% oxygenated monoterpenes, with trans-piperitone epoxide (46%), cis-piperitone epoxide (22%), and piperitenone oxide (11%) as more abundant compounds. Likewise, S. macrostema EOs showed an antioxidant activity of DPPH = 82%, with 50% free radical scavenging (IC50) = 7 mg/mL and TEAC = 0.005, an antibacterial effect against E. coli of 73% inhibition, and 81% over S. aureus at dose of 100 µL of undiluted crude oil. The TLC-DB assay showed that the most active compounds were derived from piperitone. The comparison with other studies on S. macrostema shows variability in the compounds and their abundances, which can be attributed to climatic factors and the maturity of plants with similar antioxidant and antibacterial activities.

Peptides Derived from Glycoproteins H and B of Herpes Simplex Virus Type 1 and Herpes Simplex Virus Type 2 Are Capable of Blocking Herpetic Infection in vitro.

AIMS: The aim of this study was to design peptides derived from glycoproteins H (gH) and B (gB) of herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) with the potential to block herpetic infection and to evaluate their ability to inhibit HSV-1 and HSV-2 infection in vitro. METHODS: A library of continuous 15-25 residue stretches (CRSs) located at the surface of gH and gB from HSV-1 and HSV-2 was created. These CRSs were analyzed, and only those that were highly flexible and rich in charged residues were selected for the design of the antiviral peptides (AVPs). The toxicity of the AVPs was evaluated by MTT reduction assays. Virucidal activity of the AVPs was determined by a plaque reduction assay, and their antiviral effect was measured by cell viability assays. RESULTS AND CONCLUSION: Four AVPs (CB-1, CB-2, U-1, and U-2) derived from gB and gH were designed and synthetized, none of which showed high levels of toxicity in Vero cells. The U-1 and U-2 gB-derived AVPs showed high virucidal and antiviral activities against both HSV-1 and HSV-2. The gH-derived peptide CB-1 showed high virucidal and antiviral activities against HSV-2, while CB-2 showed similar results against HSV-1. The peptides CB-1 and CB-2 showed higher IC50 values than the U-1 and U-2 peptides.