The chemical composition and in vitro anti-nanobacterial activity of Origanum majorana\n(Marjoram), Rosmarinus officinalis (Rosemary) Salvia officinalis (Sage) essential oils of the\nLamiaceae family were compared. Hexane extract of the three oils were analyzed by gas\nchromatography coupled with mass spectrometry (GC/MS). To evaluate the in vitro antinanobacterial\nactivity of these aromatic oils against nanobacteria isolated from human kidney stones a\nmodified micro-dilution inhibitory test in 96-well plates was used. An inoculation of nanobacteria in\nDulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% gamma-irradiated fetal calf\nserum (?-FBS) under cell culture conditions with tested oils in different concentrations and\ndetermination of inhibition by weekly measurement of the absorbance for 42 days. The GC/MS\nanalysis resulted in the identification of fifteen compounds from each of tested oil. The prevailing\nchemical components of sage essential oil were 1,8-Cineole (78.13%), Cis-Ocimene (9.23%) and\nCamphor (4.33%). Rosemary essential oil components were identified as 1,8-Cineole (61.70%), à-\nPinene (17.05%) and Bornanone (9.06%), While the analysis of marjoram oil revealed somewhat\ndifferent major constituents as l-4-Terpineol (24.76%), ç-Terpinene (14.17%), Sabinene (11.86%),\nand à-Humulene (10.75%). Only sage oil was found to be highly bacteriostatic at 125 ?g ml-1 and\nbactericidal at 250 ?g ml-1. While marjoram and rosemary essential oils had no activity against\nnanobacterial isolates even at higher concentrations. The presence of all types of monoterpenes as the\npredominant constituents of sage oil could be responsible for the potential anti-nanobacterial activity.\nThe antibacterial activity depends not only on chemical composition of functional groups but also the\npercent of active constituents with different biochemical properties

Marine actinomycetes are the best producer of bioactive compounds of medical or economical value.\nThe present study aimed to the evaluation of bioactive compounds produced by Streptomyces sp.\nNyr04 isolated from mangrove sediment collected from Red Sea coast. Waksman’s glucose medium\nwas the best medium for maximal antimicrobial activity. The crude extract exhibited significant\nantimicrobial activity against Bacillus subtilis, Escherichia coli, Salmonella sp., Vibrio sp., Aspergillus\nniger and Fusarium sp. The antioxidant activity of the crude extract was detected using DPPH (1, 1-\nDiphenyl-2-picrylhydrazyl) radical scavenging activity and was found to be concentration dependent.\nTLC bioautography approach revealed the presence of bioactive compounds with different Rf values\nexhibiting antimicrobial and antioxidant activities. The extract showed ?-amylase inhibition activity of\n76.25% at concentration of 60mg/ml. The present investigation suggests that the isolate Streptomyces\nsp. Nyr04 could be potential source for bioactive compound(s) exhibiting varying biological activities.