Optimization of choline chloride-glycerol based natural deep eutectic solvent for extraction bioactive substances from Cinnamomum burmannii barks and Caesalpinia sappan heartwoods

Abstract

Indonesian cassia (Cinnamomum burmannii Blume) is commonly used as a condiment. It reportedly contains a number of major phytochemical constituents such as trans-cinnamaldehyde and coumarin. Sappan wood (Caesalpinia sappan) is a native plant of Southeast Asia that contains brazilin, a widely known red pigment. This study aimed to determine the optimal extraction conditions using a choline chloride-glycerol (ChCl-glycerol)-based natural deep eutectic solvent (NADES) to obtain greater trans-cinnamaldehyde and brazilin levels from Indonesian cassia and sappan wood. The powders of Indonesian cassia and sappan wood were extracted using ChClglycerol-based NADES varied at three different levels: ratio of ChCl to glycerol, ratio of powder to NADES, and the amount of water in NADES. All variables were designed using the Box-Behnken design of response surface methodology to provide 15 extraction conditions. The extraction was performed using ultrasonication-assisted extraction for 30 and 50 min for Indonesian cassia and sappan wood, respectively. Determination of the active compound contents was performed using a high-performance liquid chromatography system equipped with a UV-VIS detector at λmax ¼ 280 nm. The optimization results revealed that the highest levels of transcinnamaldehyde, coumarin, and brazilin in NADES extracts were 1907.32, 1735.68, and 368.67 μg/ml, respectively, whereas the lowest levels of these compounds were 453.59, 616.76, and 74.21 μg/ml, respectively. The maximal levels exceeded those obtained using a conventional extraction method, in which 5000 μg/ml Indonesian cassia reflux extract contained only 108.45 μg/ml trans-cinnamaldehyde. Similarly, 1000 μg/ml sappan wood contained only 124.64 μg/ml brazilin. ChCl-glycerol-based NADES was suitable for extracting active compounds from Indonesian cassia and sappan wood; moreover, this solvent is more effective than organic ethanolic coventional solvent.

Simultaneous Natural Deep Eutectic Solvent-Based Ultrasonic-Assisted Extraction of Bioactive Compounds of Cinnamon Bark and Sappan Wood as a Dipeptidyl Peptidase IV Inhibitor

“…According to the resulting study (previously reported by Sakti et al 2019), the optimum extraction method for cinnamon bark and sappan wood was 20% v / v water content in NADES, a sample–NADES ratio of 1:4 w / w , and a choline chloride–glycerol ratio of 2:1 w / w (Method I) and 47.6% v / v water content in NADES, a sample–NADES ratio of 2:1 w / w , and a choline chloride–glycerol ratio of 1:2 w / w (Method II), respectively [ 20 ]. Furthermore, both methods were applied for the simultaneous extraction of a combination of cinnamon bark and sappan woods at a ratio of 1: 1 w / w .…”

“…NADES was prepared by mixing choline chloride with glycerol in a beaker glass covered with parafilm using a magnetic stirrer at 80 °C with the speed of 900 rpm until the mixture turned into a clear liquid solution [ 19 ]. The NADES extraction process was conducted by an ultrasonicator with a power of 35 W and frequency of 42.000 Hz for 30 and 50 min for cinnamon bark and sappan wood, respectively [ 20 , 23 , 24 ]. The powder samples were mixed with demineralized water and NADES.…”

“…The simultaneous NADES-UAE process was performed according to the previous study [ 20 ]; two optimum extraction methods were obtained to extract marker compounds contained in sappan and cinnamon using NADES with a choline chloride–glycerol composition. Both methods were used to extract the target marker compound from a combination of sappan wood and cinnamon bark (1:1 w / w ) as presented in Table 3 .…”

“…Analysis of marker compounds was performed using high-performance liquid chromatography (HPLC) based on a previous study [ 20 ], with 280 nm UV-Vis detection. Briefly, a total of 100 µL of samples was dissolved in 80% v / v ethanol.…”

“…In previous studies, optimum conditions were obtained in the extraction process of marker compounds from cinnamon bark and sappan wood [ 20 ]. However, research has not been reported related to simultaneous NADES-based UAE (NADES-UAE) of bioactive compounds from the combination of cinnamon bark and sappan wood as DPP IV inhibitors.…”