Optimization of the Ultrasound-Assisted Extraction of Bioactive Compounds from Cannabis sativa L. Leaves and Inflorescences Using Response Surface Methodology

Abstract

This study investigated the effects of particle size and ultrasonic parameters on the yields of bioactive compounds extracted from the leaves and inflorescences of hemp. The total flavonoid and anthocyanin contents were determined using the spectrophotometric method. The response surface methodology (RMS) was employed to optimize the yield of bioactive substances. On the basis of the developed model, the highest flavonoid yield was obtained under the following extraction conditions: particle size, 0.59 mm; extraction time, 10.71 min; ultrasound intensity, 7.13 W∙cm−2; extraction yield, 9.28 mg QE∙g−1; determination coefficient, R2 = 0.97. The optimal conditions for extracting anthocyanins were as follows: particle size, 0.25 mm; extraction time, 15 min; ultrasound intensity, 8.60 W∙cm−2; extraction efficiency, 20.27 mg Cy-GE∙100 g−1; determination coefficient, R2 = 0.87. This study helped confirm the importance of pulsed ultrasound-assisted extraction in obtaining bioactive compounds from hemp.

Meta‐analysis and review of cannabinoids extraction and purification techniques

“…Patent: cannabinoid extraction in ethyl acetate and subsequent isolation methods Soxhlet [105] THC, THCA, CBN Methanol, n-hexane 2 g in 4 h in 75 ml of solvent, 1-3 h Soxhlet [121] -Ethanol-H 2 O Patent: closed-loop reflux extractor employing azeotropic water-ethanol mixture Hydrodistillation [122] Terpenes H 2 O 3 h, particle size: 200-600 μm, clevenger type apparatus Steam distillation, hydrodistillation [123] Terpenes and liquid micro-jets, which incites mixing and trichome rupture. [130] When implemented in tandem with solvents, ultrasound mitigates the drawbacks of conventional methods, including their long extraction times and high solvent and energy consumption. [131] However, ultrasound also hinders extraction of thermolabile compounds, which degrade due to excessive ultra-sonication power or time.…”

“…[ 117 ] The resulting micro‐environment aids overall mass transfer by generating high shear stresses and liquid micro‐jets, which incites mixing and trichome rupture. [ 130 ] When implemented in tandem with solvents, ultrasound mitigates the drawbacks of conventional methods, including their long extraction times and high solvent and energy consumption. [ 131 ]…”

Effect of the Shape of Ultrasonic Vessels on the Chemical Properties of Extracts from the Fruit of Sorbus aucuparia

“…The independent variables consisted of extraction time (X 1 ), ultrasound amplitude (X 2 ), and solvent concentration (X 3 ), while the dependent variables included total phenolic content (TPC), antioxidant activity measured using DPPH, FRAP, and ABTS assays, and pH. The experiment comprised a total of 15 randomly conducted combinations, including 3 center points utilised for estimating the pure error [20]. The levels of the three factors evaluated in the experiment are shown in Table 1.…”

“…The levels of the three factors evaluated in the experiment are shown in Table 1. A second-order polynomial model was employed to demonstrate the impact of the independent variables on the response variable using the following equation [20].…”

“…The independent variables are denoted as X 1 , X 2 , and X 3 . The equation includes the constant term β 0 , as well as the linear (β 1,2,3 ), quadratic (β 11,22,33 ), and interactive (β 12,13,23 ) coefficients [20].…”