Isolation of essential oil from Lavandula angustifolia by using ultrasonic-microwave assisted method preceded by enzymolysis treatment, and assessment of its biological activities

This research study aimed to optimize innovative conditions for enhancing yield and quality of essential oil isolated from Lavandula angustifolia (La) based on rapid and innovative techniques. Ultrasonic-microwave assisted preceded by enzymolysis treatment was used to isolate essential oil (EO) of La. Response Surface Methodology was employed for the same purpose. The yield % of La essential oil (La.EO) obtained from combined enzymes treatment (cellulase and hemicellulase) was higher than that obtained by a single enzyme treatment. Chemical composition analysis of La.EO isolated was carried out using GC-MS. Morphological structure of La tissues was observed using SEM. The anti-free radical activity was assayed using DPPH and ABTS+ methods The isolation conditions consisted of the concentration of enzymes (12.5 mg) with a range of (5–20 mg), sonication time (52.5 min) with a range of (15–90 min) and microwave power (275W) with a range of (500–50W). The uses of coupling ultrasonic-microwave could be lead to forming of the acoustic cavitation and rupture of plant tissue. This facilitates the flow of liquid phase into the glandular trichomes in plant cells and enhances the absorption from the matrix of plant. Thus, enhances the efficiency of essential oil isolation from aromatic plant based on cavitation phenomenon. The results of the current work found that La.EO which isolated by using ultrasonic-microwave techniques under optimal conditions could be used as food additives in food industries to prevent the oxidation and bacterial spoilage.本研究旨在基于快速创新技术，优化狭叶薰衣草（Lavandula angustifolia，La）精油的提取工艺条件，以提升其得率与品质。本研究采用酶解预处理结合超声-微波辅助的方法提取狭叶薰衣草精油（essential oil，EO），并采用响应面法（Response Surface Methodology）优化工艺参数。复合酶（纤维素酶与半纤维素酶）处理所得的狭叶薰衣草精油（La.EO）得率高于单一酶处理组。采用气相色谱-质谱联用仪（GC-MS）对提取得到的La.EO进行化学成分分析；采用扫描电子显微镜（SEM）观察狭叶薰衣草组织的微观形态结构；采用DPPH与ABTS+法测定其抗氧化自由基活性。本研究的提取工艺参数包括：酶投加量（基准值12.5 mg，取值范围5~20 mg）、超声处理时间（基准值52.5 min，取值范围15~90 min）以及微波功率（基准值275W，取值范围500~50 W）。超声-微波联用可引发声空化效应，破坏植物组织结构，促进液相渗透进入植物细胞的腺毛结构，强化精油从植物基质中的溶出，从而基于空化效应提升芳香植物精油的提取效率。本研究结果表明，在最优工艺条件下通过超声-微波辅助法提取的La.EO，可作为食品添加剂应用于食品工业，用于抑制氧化与细菌腐败。