Green extraction optimization of triterpenoid glycoside-enriched extract from Centella asiatica (L.) Urban using response surface methodology (RSM)

Abstract

Centella asiatica (L.) Urban extracts are widely used as food, drugs and cosmetics, and the main active compounds are glycosides (madecassoside and asiaticoside) and aglycones (madecassic acid and asiatic acid). Green extraction is an interesting concept that can produce safe and high-quality extracts that use less solvent, time and energy with the environmental friendly. This study investigated the optimum conditions for extracting a triterpenoid glycoside-enriched C. asiatica extract using microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE). Central composite design and response surface methodology (RSM) were used for the experimental design and data analysis. Four-month-old C. asiatica tetraploid plants were selected as the elite raw material containing high amount of triterpenoid glycosides for the extraction experiments, and the triterpenoid content was determined by a validated HPLC method. The results demonstrated that the RSM models and equations were reliable and could predict the optimal conditions to enhance C. asiatica extract yield, glycoside and aglycone amounts. The percent of ethanol was the major factor that had a significant effect on C. asiatica yield and glycoside and aglycone content during MAE and UAE. The maximum triterpenoids content in extract; 7.332 ± 0.386% w/w madecassoside and 4.560 ± 0.153% w/w asiaticoside 0.357 ± 0.013% w/w madecassic acid and 0.209 ± 0.025% w/w asiatic acid were obtained by MAE with 80% ethanol at 100 watts for 7.5 min, whereas the optimal conditions for highest total triterpenoids extraction from dry plant was UAE with 80% ethanol, temperature 48 °C, 50 min enhanced 2.262 ± 0.046% w/w madecassoside, 1.325 ± 0.062% w/w asiaticoside, 0.082 ± 0.009% w/w madecassic acid and 0.052 ± 0.007% w/w asiatic acid as secondary outcome. Moreover, it was found that MAE and UAE consumed energy 59 and 54%, respectively, lower than that of the conventional method, maceration, in term of kilowatt-hour per gram of total triterpenoids. These optimized green conditions could be recommended for C. asiatica extraction for triterpenoid glycoside-enriched extracts production for the pharmaceutical or cosmeceutical industries and triterpenoids quantitative analysis in raw materials.

Experimental modelling studies on the removal of dyes and heavy metal ions using ZnFe2O4 nanoparticles

“…The closer the variances, the lower the F-value. Therefore, the higher F-value for a response shows that the variables and their levels have a more significant effect on the response 28 , 29 . As can be seen from Tables S2 and S3 , the F-values for removing AO, MB, and Cd (II) were 261.05, 246.68, and 158.18, respectively.…”

Combining DoE and MASE: a winning strategy for the isolation of natural bioactive compounds from plant materials

“…Furthermore, a recent work estimated that MASE consumed 59% less energy (expressed in kilowatt-hour per gram of total triterpenoids) than maceration. 50 The most exploited RSM model was the Box-Behnken design (BBD, 30 articles, 48%), followed by the central composite design (CCD, 21 articles, 33%). The success of these two models lies in the fact that they highlight the interactions between parameters and require a limited number of experi- ments.…”

“…Furthermore, a recent work estimated that MASE consumed 59% less energy (expressed in kilowatt-hour per gram of total triterpenoids) than maceration. 50…”

Optimization of reaction temperature and Ni–W–Mo catalyst soaking time in oil upgrading: application to kinetic modeling of in-situ upgrading

“…The RSM approach consists of full factorial or fractional factorial design, additional design, and a central point. By these modalities, information can be provided in the form of cubic or quadratic diagrams 42 , 43 . Standard statistical software would count the exact access of the model.…”