GREEN APPROACH TO PHYTOCHEMICALS: ALKALOIDS PURIFICATION AS USED IN HEALTH THERAPEUTICAL AND WELLNESS ACTIVITIES
Authors: Haq Ehsan Ul , Afzal Esha , Aslam Misha , Zafar Farwa , Assad Nasir 
Published: February 2025

Background: Alkaloids are bioactive nitrogenous compounds with significant pharmacological applications, including analgesic, anti-inflammatory, anticancer, neuroprotective, and antimicrobial effects. Conventional extraction methods rely on toxic organic solvents, leading to environmental concerns and inefficiencies in yield and purity. The adoption of green extraction technologies, such as Supercritical Fluid Extraction (SFE), Microwave-Assisted Extraction (MAE), and Ultrasound-Assisted Extraction (UAE), offers a sustainable and efficient alternative. These methods enhance extraction efficiency, reduce processing time, and minimize solvent toxicity, ensuring safer and more effective therapeutic applications.
Objective: This study aimed to evaluate and compare the efficiency of SFE, MAE, and UAE in the extraction, isolation, and purification of alkaloids from Papaver somniferous and Erythroxylon coca. The focus was on optimizing extraction conditions to maximize yield, purity, and recovery while minimizing environmental impact.
Methods: Plant materials were sourced from authenticated suppliers, processed into fine powder, and stored under controlled conditions. SFE, MAE, and UAE were performed under optimized conditions, with SFE utilizing CO₂ as a supercritical solvent at 40°C and 2500 psi with a 12 g/min flow rate. The extracted alkaloids were quantified using UV-Vis spectrophotometry and high-performance liquid chromatography (HPLC) with an Agilent C18 reverse-phase column and a mobile phase of acetonitrile-water (50:50) at a flow rate of 1.0 mL/min. Statistical analysis, including one-way ANOVA and Tukey’s HSD post hoc test, was conducted to determine significant differences in extraction performance (p < 0.05). Recovery rates, purity levels, and solvent consumption were also assessed for each method.
Results: SFE yielded the highest alkaloid concentrations, with P. somniferous producing 25.7 mg/g of morphine and 18.3 mg/g of codeine, outperforming MAE (22.4 mg/g and 15.2 mg/g) and UAE (19.5 mg/g and 13.1 mg/g). E. coca yielded 30.4 mg/g of cocaine via SFE, significantly higher than MAE (26.8 mg/g) and UAE (23.5 mg/g). HPLC purity analysis showed SFE resulted in 97% purity for morphine, 91% for codeine, and 98% for cocaine, surpassing MAE (91%, 87%, and 93%) and UAE (87%, 83%, and 89%). Recovery rates were highest for SFE (96.8% for P. somniferous, 95.6% for E. coca), exceeding those of MAE (93.4%, 91.8%) and UAE (90.1%, 88.2%). Solvent consumption was lowest for SFE, requiring only 15 mL per gram of alkaloid, compared to MAE (27 mL) and UAE (34 mL). The coefficient of variation (CV) was lowest for SFE (4.1%), demonstrating superior precision over MAE (5.7%) and UAE (7.2%).
Conclusion: This study confirms that SFE is the most effective, precise, and environmentally sustainable technique for alkaloid extraction, yielding the highest purity and recovery rates while minimizing solvent waste and environmental impact. The findings support the adoption of green extraction methodologies for large-scale pharmaceutical applications, ensuring safer and more efficient production of high-purity alkaloids for therapeutic use.