Phytochemical Screening and Anti-inflammatory Activity (Nitric Oxide) in Development of Knee Pain Relief Cream by Nanoemulsion from Cannabis sativa L. Extract

Abstract

This study investigated the phytochemical components, anti-inflammatory activity, and development of a knee pain relief cream using nanoemulsion technology from cannabis leaf extract of the Charlotte’s Angel strain, extracted with ethanol. The phytochemical analysis revealed that the cannabis leaf extract contains active ingredients such as alkaloids, saponins, tannins, terpenoids, and cardiac glycosides. The extract had a polyphenolic compound content of 72.70±0.03 μg GAE/mg extract. The tetrahydrocannabinol (THC) and cannabidiol (CBD) analysis using high performance liquid chromatography (HPLC) presented that the CBD content was 208.2 ±0.47 μg/ml, and THC was 5.91±0.05 μg/ ml. The toxicity exploration of the cannabis leaf extract on human keratinocyte (HaCaT) and mouse macrophage (RAW 264.7) cells using the MTT assay showed that at concentrations of 1.56-100 μg/ml, the percentage of cell viability was 106.17-13.12 for HaCaT and 96.15-10.58 for RAW 264.7. Extract concentrations above 50 μg/ml exhibited cytoxicity to the cells. For the anti-inflammatory activity, inhibition of nitric oxide release from LPS-stimulated RAW 264.7 cells at concentrations of 1.56 - 25 μg/ml showed inhibition rates of 84.61 – 97.85%. The development of the knee pain relief cream using nanoemulsion technology from cannabis leaf extract resulted in a semi-solid cream product containing suspended small particles. Temperature changes under accelerated conditions (6 cycles) did not affect the emulsion’s stability. Microbiological analysis displayed no growth of microorganisms and fungi. Size and zeta potential measurements using dynamic light scattering (DLS) indicated that the best formula had a hydrodynamic diameter of 234.52±4.65 nm, a polydispersity index (PDI) of 0.44±0.02, and a zeta potential of -29.60±0.59 mV, representing good suspension stability. The results of this study provide a guideline for developing a knee pain relief cream using nanoemulsion technology from cannabis leaf extract. This product has the potential for further clinical development in the treatment of osteoarthritis in the elderly, which could significantly improve their physical quality of life in the future.