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1.
Artigo | IMSEAR | ID: sea-210548

RESUMO

This study aimed to determine the optimum method for extracting caffeine and chlorogenic acid (CGA) from greencoffee beans (GCB) of Coffea canephora using choline chloride–sorbitol, a natural deep eutectic solvent (NADES).Three different preparations of choline chloride–sorbitol and choline chloride–sorbitol–urea (2:1, 4:1, and 6:1) wereused for the extraction. The most effective preparation was used to evaluate the effect of dilution with water andextraction time. Reverse-phase high-performance liquid chromatography, with a gradient solvent system of 0.1%acetic acid (90%) and acetonitrile (10%), was used to quantify the CGA and caffeine. Choline chloride–sorbitol ata ratio of 4:1 was the most effective for extracting chlorogenic and caffeine, with caffeine and CGA yield of 4.49and 16.59 mg/g dry weight, respectively. The optimum water concentration was not found. Using a higher NADESdilution for extraction corresponded to an increased yield of caffeine and CGA. The effective time for extraction wasfound to be 30 minutes, which yielded the most caffeine and CGA. Based on these results, choline chloride–sorbitolcould be an alternative green solvent for extracting caffeine and CGA from C. canephora GCB.

2.
Asian Pacific Journal of Tropical Biomedicine ; (12): 257-262, 2019.
Artigo em Chinês | WPRIM | ID: wpr-753239

RESUMO

Objective: To isolate, identify, and evaluate a new angiotensin-converting enzyme inhibitor from Peperomia pellucida (L.) Kunth herbs. Methods: A dried sample of Peperomia pellucida herb was successively macerated with n-hexane and ethyl acetate. The ethyl acetate extract solution was evaporated to obtain the crude extract. Vacuum liquid column chromatography and thin layer chromatography were performed to obtain two pure compounds. Then, both compounds were elucidated and identified using the spectroscopic method. Angiotensin-converting enzyme inhibitory activity studies of both compounds were determined using angiotensin-converting enzyme kit WST-1 with spectrophotometer microplate reader 96-well at 450 nm wavelength. Results: Two bioactive compounds were successfully isolated from Peperomia pellucida herb, including a new compound of 2,3,5-trimethoxy-9-(12,14,15-trimethoxybenzyl)-1H-indene and pellucidin A. Both compounds demonstrated angiotensin-converting enzyme inhibitory activity, with IC50 values of 72 μM (27.95 μg/mL) and 11 μM (4.4 μg/mL), respectively. Conclusions: In the present study, two active angiotensin-converting enzyme inhibitors were successfully isolated and purified from Peperomia pellucida which is used as an antihypertensive in traditional medicine, and support its use as an angiotensin-converting enzyme-inhibiting drug.

3.
Asian Pacific Journal of Tropical Biomedicine ; (12): 660-665, 2017.
Artigo em Chinês | WPRIM | ID: wpr-686633

RESUMO

Objective: To optimize the ionic liquid based microwave-assisted extraction (IL-MAE) of polyphenolic content from Peperomia pellucida (L) Kunth. Methods: The IL-MAE factors as experimental design parameters, including microwave power, extraction time, ionic liquid concentration, and liquid–solid ratio had been involved. Response surface methodology and Box–Behnken design were used to obtain predictive model (multivariate quadratic regression equation) and optimization of the extraction process. The response surface was analyzed by using the yields of total polyphenolic content as response value. Results: Based on the obtained results the optimum extraction condition, including microwave power of 30% Watts, extraction time of 18.5 min, the ionic liquid concen-tration of 0.79 mol/L, and the liquid–solid ratio of 10.72 mL/g 1-Buthyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) as a solvent was selected. The regression model was obtained to predicts the yields from Peperomia pellucida:Y = 30.250 – 1.356X1 + 2.655X2 + 2.252X3 – 0.565X4 + 0.990 X1X3 – 8.172 X1X4 – 3.439 X3X4 – 4.178 X12 – 3.210 X32 – 6.786 X42 – 7.290 X12X3 + 5.575 X1X32 – 4.843 X32X4 with R2 = 0.82519. Scale-up confirmation test was obtained the maximum yields of total polyphenolics content with the amount of 31.1725μg GAE/g. Conclusions: The IL-MAE method produced a higher extraction polyphenolic and performed rapidly, easily and efficiently.

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