Background
Ocimum genus known as Tulsi or Basil is a prominent botanical class in Asian culture, especially in India. The leaves have an immunomodulatory, antioxidant, stress-relieving, and adaptogenic role in traditional and modern medicine, with prominent usage in herbal teas and nutraceuticals.
Objective
The HPLC-PDA method was developed and validated for vicenin-2, orientin, cynaroside, betulinic acid, genistein, with syringic acid, rosmarinic acid, eugenol, carnosic acid, oleanolic acid, ursolic acid, luteolin, apigenin for quantification and confirmed using a novel ESI -MS/MS method in the Ocimum samples.
Method
The methodology parameters were developed on the RP-C18 column with a gradient elution of 1 mL/min flow rate for 0.1% o-phosphoric acid and acetonitrile at 210 and 340 nm wavelengths.
Result
The validation data for 13 bioactive compounds showed good linearity (r2> 0.99) with sensitive LOD (0.034-0.684 µg/mL) and LOQ (0.100-2.068 µg/mL) with recoveries (83.66-101.53%).The results were found precise (RSD,<5.0%) and accurate (RE, -0.60-1.06) for the quantification. The method performance was verified and found robust by analyzing ten samples of O. tenuiflorum from the ten geographical states of India (RSD, < 5.0%).
Conclusion
The validated HPLC-PDA method was found selective and suitable for analyzing thirteen compounds in O. tenuiflorum and twelve cultivars from the Ocimum genus as a quality control tool. This method can be used in routine analysis as an inexpensive alternative to advanced techniques.
Highlights
This work is the first to report for vicenin-2, orientin, cynaroside, betulinic acid, and genistein, with simultaneous analysis of eight bioactive compounds in the Ocimum genus.