In this study, radical scavenging and antifungal activities of Chaerophyllum macropodum and Oliveria decumbens essential oils (EOs) extracted with microwave-assisted hydrodistillation (MAHD) were evaluated in comparison with the same EOs extracted by conventional hydrodistillation (HD). The final EO yields that were obtained using HD (after 150 min) and MAHD (after 45 min) were 1.72 and 1.67% for C. macropodum and 8.10 and 7.91% for O. decumbens, respectively. There were no significant differences between the final EO yields extracted with HD and MAHD, but MAHD could significantly reduce the duration of the extraction operation. Average rates of EO accumulation (grams per minute) with MAHD were at least three times higher than with HD. Gas chromatography-mass spectrometry analysis of EOs indicated that there were no significant differences between the composition of EOs extracted by HD and MAHD. Both plants showed high radical scavenging activity, with 50% inhibitory concentration values of 0.430 to 0.431 mg/mL for C. macropodum and 0.142 to 0.146 mg/mL for O. decumbens. Antifungal activity was performed against six fungal species, including Aspergillus niger , Aspergillus oryzae , Penicillium chrysogenum , Trichoderma harzianum, Byssochlamys spectabilis, and Paecilomyces variotii. A. niger and A. oryzae were the most resistant fungi, and T. harzianum was the most susceptible. Evaluation of MIC and minimum fungicidal concentration values showed that the O. decumbens EOs were very active against all the tested fungi, which can be attributed to the high amounts of oxygenated terpenes in the EO content. Therefore, MAHD as a fast extraction technique did not have any adverse effects on chemical composition, radical scavenging activity, and antifungal activity of C. macropodum and O. decumbens EOs.

The aim of this work was to develop and optimize process parameters in ultrasound and sono‐assisted alkaline pretreatment of sugarcane bagasse prior to hydrolysis and bioethanol fermentation processes. Following the optimization of ultrasound time and temperature, the influence of concentration of NaOH solution was examined. The optimal condition in ultrasound pretreatment (35 kHz) was achieved at 5 min and 65C. Ultrasound pretreatment of bagasse prior to hydrolysis step resulted in increased sugar concentration from 3.62 g/L (control, 25C) to 5.78 g/L (65C, 5 min). The micromorphology and cellulose crystallinity for native and pretreated bagasse were investigated by scanning electron microscopy and X‐ray diffraction, respectively. The maximum glucan conversion and bioethanol production of 50% and 0.38 g/g glucose were achieved following sono‐assisted alkaline pretreatment (3% NaOH concentration), respectively. The findings indicate that sono‐assisted alkaline pretreated bagasse can be used as a potential feedstock in bioethanol production. Practical Applications Current bioethanol production uses food crops such as sugarcane and maize. Large amounts of sugar molecules are present in the lignocellulose of plant material and current research aims to “unlock” the fermentable sugars in agricultural or forestry wastes and residues. The objective of the present research was to find an optimum pretreatment method by combining ultrasound with various concentrations of mild alkaline solution in order to make use of a greater proportion of lignocellulose materials from the sugarcane bagasse for bioethanol production. The development of an efficient pretreatment to increase the cellulose digestibility and fermentability potential of biomass may be of interest in bioethanol industries.

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