Valorization of chili seed by-product: extraction of essential oil and its potential application in nanoemulsion development
摘要
This study aimed to valorize the chili seed, a by-product of the spice industry by extraction of essential oil and its strategic utilization in the development of nanoemulsions with potential industrial applications. Ultrasonication extraction was utilized for efficient essential oil recovery from chili seeds. The extracted essential oil was utilized for the development of nanoemulsions. The developed nanoemulsions showed Herschel–Bulkley behavior, with yield stresses ranging from 0.997 to 0.999 and flow index (n) values ranging from 0.426 to 0.532. The particle sizes of the 0.5 NE, 1.0 NE, 1.5 NE, and 2.0 NE nanoemulsions were 61, 104, 124, and 127 nm, respectively. A notable decrease in the L* value was observed, whereas a* and b* values significantly increased (p < 0.05). The zeta potentials of nanoemulsions were − 28 mV, − 25 mV, − 21 mV, and − 18 mV, respectively. The peak in the FTIR spectrum at 3300–3600 cm−1 is due to xanthan and oil O–H groups, the peak at 1722 cm−1 represents C = O stretching, the peak at 2923 cm−1 represents C-H stretching, and the peak at 1732 cm−1 represents carbonyl groups in chili seed oil. The DPPH inhibition activity was 20%, 32%, 38%, and 44%, with ABTS activity was 14%, 18%, 20% and 25%. The nanoemulsion demonstrated inhibition zones of 3.2 mm, 3.8 mm, 4.6 mm, and 5.2 mm against E. coli, whereas, for Salmonella, the inhibition zones were 2.5 mm, 2.8 mm, 3.1 mm, and 4.3 mm.
Graphical abstract