Optimization of Extraction Conditions for Maximal Phenolic, Flavonoid and Antioxidant Activity from Melaleuca bracteata Leaves Using the Response Surface Methodology

Abstract

Melaleuca bracteata is a yellow-leaved tree belonging to the Melaleuca genus. Species from this genus are known to be good sources of natural antioxidants, for example, the “tea tree oil” derived from M. alternifolia is used in food processing to extend the shelf life of products. In order to determine whether M. bracteata contains novel natural antioxidants, the components of M. bracteata ethanol extracts were analyzed by gas chromatography–mass spectrometry. Total phenolic and flavonoid contents were extracted and the antioxidant activities of the extracts evaluated. Single-factor experiments, central composite rotatable design (CCRD) and response surface methodology (RSM) were used to optimize the extraction conditions for total phenolic content (TPC) and total flavonoid content (TFC). Ferric reducing power (FRP) and 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH·) scavenging capacity were used as the evaluation indices of antioxidant activity. The results showed that the main components of M. bracteata ethanol extracts are methyl eugenol (86.86%) and trans-cinnamic acid methyl ester (6.41%). The single-factor experiments revealed that the ethanol concentration is the key factor determining the TPC, TFC, FRP and DPPH·scavenging capacity. RSM results indicated that the optimal condition of all four evaluation indices was achieved by extracting for 3.65 days at 53.26°C in 34.81% ethanol. Under these conditions, the TPC, TFC, FRP and DPPH·scavenging capacity reached values of 88.6 ± 1.3 mg GAE/g DW, 19.4 ± 0.2 mg RE/g DW, 2.37 ± 0.01 mM Fe2+/g DW and 86.0 ± 0.3%, respectively, which were higher than those of the positive control, methyl eugenol (FRP 0.97 ± 0.02 mM, DPPH·scavenging capacity 58.6 ± 0.7%) at comparable concentrations. Therefore, the extracts of M. bracteata leaves have higher antioxidant activity, which did not only attributed to the methyl eugenol. Further research could lead to the development of a potent new natural antioxidant.

Optimization of Microwave-Assisted Extraction for the Recovery of Bioactive Compounds from the Chilean Superfruit (Aristotelia chilensis (Mol.) Stuntz)

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Egg Yolk Phosphatidylethanolamine: Extraction Optimization, Antioxidative Activity, and Molecular Structure Profiling

“…To study the effect of the global behavior of multiple factors and their interactions on a desired response, response surface methodology (RSM) has been applied as an effective tool for determining optimum conditions (Cabezas et al., ; Ding, Zheng, Xia, Ren, & Kan, ; Hou, Zhang, Chen, & Luo, ; Mohammadi et al., ). RSM is a collection of mathematical and statistical techniques, which uses quantitative data from an experimental design, to simultaneously determine and solve multivariable equations to optimize processes or products (Madamba, ).…”

Optimization of a Novel Kinetic-Assisted Infundation for Rich-Egcg and Polyphenols of White Tea (Camellia Sinensis) Using Central Composite Design

“…This KAI technique regulates a fixed temperature at 90 °C referring to the basic technique. Temperature and stirring speed can affect extraction time [13,18,19,22]. Temperature dramatically influences solubility of solutes, diffusion coefficients and dielectric water constants [15,19,23].…”