Ultrasonic vacuum synergistic assisted ethanol extraction of steviol glycosides and kinetic studies

• Published in: Industrial crops and products 2024-12, Vol.221, p.119385, Article 119385
• Main Authors: Huang, Chengxia, Wang, Yang, Zhou, Cunshan, Sun, Qiaolan, Zhang, Lei, Niu, Yunwei, Yao, Deyang, Song, Linglin, Okonkwo, Clinton Emeka, Phyllis, Otu, Ma, Haile
• Format: Article
• Language: English
• Subjects: antioxidant activity; antioxidants; ethanol; Extraction kinetics; glycosides; kinetics; Stevia; Stevia rebaudiana; steviol; Steviol glycosides; temperature; ultrasonic treatment; Ultrasonic-vacuum synergy; ultrasonics
• ISSN: 0926-6690
• DOI: 10.1016/j.indcrop.2024.119385

This study developed an efficient ultrasonic-vacuum synergistic assisted ethanol extraction (UVAE) method to recover steviol glycosides (SGs) from Stevia rebaudiana. This study investigated the impact of UVAE and conventional extraction methods: hot-assisted extraction (HAE), ultrasound-assisted extraction (UAE), and vacuum-assisted extraction (VAE), on the content and physicochemical characteristics of SGs. The optimal UVAE process conditions were ultrasonic frequency (22 kHz), ethanol concentration (40 % v/v), vacuum (−0.01 Mpa), temperature (60 °C), and extraction time (20 min). At this condition, SGs yield reached 260.47 ± 1.62 mg/g, and was 17.4 %, 7.6 %, and 7.7 % higher than HAE, UAE, and VAE with 40 % (v/v) ethanol, respectively. UVAE increased SGs and antioxidant activity in stevia extracts. Furthermore, a kinetic model using Fick's second law was developed for SGs extraction via UVAE. This study suggested that UVAE is a potent technique for producing SGs and antioxidant actives from stevia and provides valuable insights into green extraction processes applicable to industrial plant matrices. [Display omitted] •First study of ultrasonic vacuum synergistic extraction (UVAE) of steviol glycosides.•UVAE reduced extraction time by 33.33 % compared to ultrasound-assisted extraction.•UVAE increased steviol glycosides and antioxidant content in Stevia rebaudiana.•Optimized UVAE parameters yielded stevia extract with a SGs content of 260.47 mg/g.