| Title: | "Characterisation of the Convective Hot-Air Drying and Vacuum Microwave Drying of Cassia alata: Antioxidant Activity, Essential Oil Volatile Composition and Quality Studies" |
| Author(s): | Chua LYW; Chua BL; Figiel A; Chong CH; Wojdylo A; Szumny A; Lech K; |
| Address: | "School of Engineering, Taylor's University, Lakeside Campus, No. 1, Jalan Taylor's, Subang Jaya, Selangor 47500, Malaysia. lisacyw92@gmail.com. School of Engineering, Taylor's University, Lakeside Campus, No. 1, Jalan Taylor's, Subang Jaya, Selangor 47500, Malaysia. beelin.chua@taylors.edu.my. Institute of Agricultural Engineering, Wroclaw University of Environmental and Life Sciences, 37a Chelmonskiego Street, 51-630 Wroclaw, Poland. adam.figiel@upwr.edu.pl. School of Engineering and Physical Sciences, Heriot-Watt University Malaysia, No. 1 Jalan Venna P5/2 Precinct 5, Putrajaya 62200, Malaysia. chien_hwa.chong@hw.ac.uk. Department of Fruit, Vegetable and Plant Nutraceutical Technology, Wroclaw University of Environmental and Life Sciences, 37 Chelmonskiego Street, 51-630 Wroclaw, Poland. aneta.wojdylo@upwr.edu.pl. Department of Chemistry, Wroclaw University of Environmental and Life Sciences, Norwida 25, 53-375 Wroclaw, Poland. antoni.szumny@upwr.edu.pl. Institute of Agricultural Engineering, Wroclaw University of Environmental and Life Sciences, 37a Chelmonskiego Street, 51-630 Wroclaw, Poland. krzysztof.lech@upwr.edu.pl" |
| DOI: | 10.3390/molecules24081625 |
| ISSN/ISBN: | 1420-3049 (Electronic) 1420-3049 (Linking) |
| Abstract: | "The preservation of active constituents in Cassia alata through the removal of moisture is crucial in producing a final product with high antioxidant activity. This study aims to determine the influences of various drying methods and drying conditions on the antioxidant activity, volatiles and phytosterols content of C. alata. The drying methods used were convective drying (CD) at 40 degrees C, 50 degrees C and 60 degrees C; freeze drying; vacuum microwave drying (VMD) at 6, 9 and 12 W/g; and two-stage convective pre-drying followed by vacuum microwave finish drying (CPD-VMFD) at 50 degrees C and 9 W/g. The drying kinetics of C. alata are best described by the thin-layer model (modified Page model). The highest antioxidant activity, TPC and volatile concentration were achieved with CD at 40 degrees C. GC-MS analysis identified the presence of 51 volatiles, which were mostly present in all samples but with quantitative variation. The dominant volatiles in fresh C. alata are 2-hexenal (60.28 mg 100 g(-)(1) db), 1-hexanol (18.70 mg 100 g(-)(1) db) and salicylic acid (15.05 mg 100 g(-)(1) db). The concentration of phytosterols in fresh sample was 3647.48 mg 100 g(-)(1) db, and the major phytosterols present in fresh and dried samples were beta-sitosterol (1162.24 mg 100 g(-1) db). CPD-VMFD was effective in ensuring the preservation of higher phytosterol content in comparison with CD at 50 degrees C. The final recommendation of a suitable drying method to dehydrate C. alata leaves is CD at 40 degrees C" |
| Keywords: | "Aldehydes/chemistry Antioxidants/*chemistry/isolation & purification Cassia/*chemistry Freeze Drying Gas Chromatography-Mass Spectrometry Hexanols/chemistry Microwaves Oils, Volatile/*chemistry Phytosterols/chemistry Plant Leaves/chemistry Salicylic Acid/;" |
| Notes: | "MedlineChua, Lisa Yen Wen Chua, Bee Lin Figiel, Adam Chong, Chien Hwa Wojdylo, Aneta Szumny, Antoni Lech, Krzysztof eng 0019/SDU/2018/18/The Polish Ministry of Science and Higher Education 'Strategy of Excellence-University of Research' Project/ TRGS/MFS/1/2017/SOE/008/Taylor's University Lakeside for providing financial support under Taylor's Research Grant Schemes/ Switzerland 2019/04/27 Molecules. 2019 Apr 24; 24(8):1625. doi: 10.3390/molecules24081625" |
