To explore the role of endophytic bacteria from a medicinal plant in the production of bioactive compounds, bacterial strains (10 different taxa) were isolated from the surface sterilized stem of healthy Ephedra foliata. The endophytes were related to Firmicutes, Actinobacteria and Proteobacteria. They were identified as members of Bacillus (5 strains), Paenibacillus (2 strains), Brevundimonas (1 strain), Kytococcus (1 strain), and Microbacterium (1 strain). The bacterial metabolites were extracted by chloroform and examined for antimicrobial, antioxidant and anticancer properties. Strain F5 (Paenibacillus) showed moderate antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli. Its antibacterial activity was enhanced 2.3 times in the optimum conditions (starch 1% w/v, malt extract 0.2% w/v, pH 7, temperature 30 ºC, inoculum size 3% v/v, and 48 h incubation time, at the basal tryptic soy broth medium). The highest DPPH scavenging capacity (EC50 at 43.0 µg/ml) was observed by the extract of the strain A1 (Microbacterium). The highest cytotoxic activity on HeLa cancerous cell was related to the extract obtain from strain A3 (Kytococcus) and its IC50 values were determined as (µg/ml) 104, 64, and 43 after 24, 48, and 72 hours, respectively. Chemical identification of the extracts by tandem mass spectrometry revealed possible presence of alkaloid, aminoglycoside, flavonoid, and terpenoid compounds as previously extracted from other medicinal plants. Our results show the great potential of these endophytes for production of plant-related bioactive compounds.

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