The progressive study aimed to determine the effects of biofertilizers (Azotobacter and Pseudomonas) on active chemical compounds of sweet basil (Ocimum basilicum L.), carried out in 2023 at the Afghan City, Kerbala, Iraq. The experiment set out in a randomized complete block design (RCBD) with a factorial arrangement and three replications. The study comprised two factors: the first was Azotobacter (control, 50, 100, 150 g/bacteria), and the second factor was Pseudomonas (control, 50, 100, 150 g/bacteria). Both biofertilizers attained mixing with seeds before planting. Results revealed significant differences among the various concentrations of Azotobacter and Pseudomonas and their interactions. Azotobacter and Pseudomonas treatment with same dilution (150 g bacteria^-1) provided the highest mean values for active chemical compounds in the essential oil, i.e., camphor (3.70 and 4.56 mg g^-1), linalool (24.83 and 24.90 mg g^-1), pinene (1.09 and 1.38 mg g^-1), myrcene (13.64 and 12.84 mg g^-1), and limonene (18.16 and 17.76 mg g^-1), respectively.

Keywords: Sweet basil (Ocimum basilicum L.), Pseudomonas, Azotobacter, active compounds

Key findings: Biofertilizers (Azotobacter and Pseudomonas) and their interactions enunciated considerable differences for active chemical compounds. Azotobacter and Pseudomonas with same concentration (150 g/bacteria) produced the highest mean values in the essential of sweet basil (Ocimum basilicum L.) for camphor (3.70 and 4.56 mg g^-1), linalool (24.83 and 24.90 mg g^-1), pinene (1.09 and 1.38 mg g^-1), myrcene (13.64 and 12.84 mg g^-1), and limonene (18.16 and 17.76 mg g^-1), respectively.