Kinetics studies on effects of extraction techniques on bioactive compounds from Vernonia cinerea leaf

Abstract

Recently, unconventional methods especially microwave-assisted hydrodistillation extraction (MAHE) is being used as an alternative technique for extracting bioactive compounds from plant materials due to its advantages over conventional methods such as Soxhlet extraction (SE). In this study, bioactive compounds were extracted from Vernonia cinerea leaf using both MAHE and SE methods. In addition, the kinetic study of MAHE and SE methods were carried out using first-and secondorder kinetic models. The results obtained showed that MAHE can extract higher yield of bioactive compounds from V. cinerea leaf in a shorter time and reduced used of extracting solvent compared with SE method. Based on the results obtained, second-order kinetic models can actually describe the extraction of bioactive compounds from V. cinerea leaf through MAHE with extraction rate coefficient of 0.1172 L/gmin and extraction capacity of 1.0547 L/g as compared to SE with 0.0157 L/gmin and 1.1626 L/g of extraction rate coefficient and extraction capacity, respectively. The gas chromatography-mass spectrometry analysis of the oil showed the presence of numerous heavy fractions in the oil obtained through MAHE as compared with the SE method. Moreover, the electric consumption and environmental impacts analysis of the oil suggested that MAHE can be a suitable green technique for extracting bioactive compounds from V. cinerea leaf.

Extraction of phenolic compounds: A review

“…Additionally, serial exhaustive extraction entails the fractionation of crude extracts with solvent of higher polarity from hexane (a non-polar solvent) to butanol (a polar solvent) to achieve the extraction of wider range of phytochemicals. This technique cannot be utilized to extract thermolabile compounds due to the prolong heating ( Alara and Abdurahman, 2019 ).…”

Extract‐rich in flavonoids from Hibiscus sabdariffa calyces: Optimizing microwave‐assisted extraction method and characterization through LC‐Q‐TOF‐MS analysis

“…It is relatively found in different parts of the world especially in Malaysia, Thailand, India, and tropical Africa. It is a shrub with diverse usages which include consumption as tea, beverages, jams, used as a dye, used in cosmetics, ice cream, and several other ways (Alara & Abdurahman, ; Alara & Abdurahman, ). A wide range of studies had reported that the extracts from H. sabdariffa calyces possessed different bioactive constituents which include phenolic compounds, anthocyanins, flavonoids, organic acids, carbohydrates, pectin, and mucilage.…”

“…Although several studied had been carried out on H. sabdariffa calyces which include the study of chemical stability, in vitro antiproliferative and antioxidant activities of anthocyanins‐rich extract from H. sabdariffa calyces (Maciel et al, ); evaluations of volatile oils for this plant (Alara & Abdurahman, ; Alara & Abdurahman, ; Inikpi, Lawal, Ogunmoye, & Ogunwande, ; Pino, Márquez, & Marbot, ); characterization of the anthocyanidin, phenolic compounds, antimicrobial, and antioxidant activities of 25 varieties of Mexican calyx extract of H. sabdariffa (Borrás‐Linares et al, ); and several other studies; however, the MAE of flavonoids from this multipurpose plant is yet to be reported. Thus, this study focused on the optimization of MAE process factors in achieving an optimal yield of total flavonoid (TF) content from H. sabdariffa calyces and identification of flavonoid compounds in the extract using liquid chromatography‐mass spectrometry quadrupole time of flight (LC‐Q‐TOF‐MS) analysis.…”

Kinetic Study on Chlorophyll and Antioxidant Activity from Polyscias fruticosa (L.) Harms Leaves via Microwave-Assisted Extraction

“…The first-order was expressed according to the work of Alara and Abdurahman (2019) [ 60 ]: where C is the chlorophyll content or antioxidant activity at different extraction times (mg/mL), C s is the saturated concentration (mg/mL), and k 1 is the first-order extraction rate constant (1/min).…”