Antioxidant activity, total phenolic and chlorophyll content of Keningau grown cucumis sativus l. at two growth stages

• Main Authors: Amir Husni Mohd Shariff, Shahirah Baharin, Roswanira Abdul Wahab, Fahrul Huyop, Nur Royhaila Mohamad, Mona Zakaria, Jumardi Roslan, Nurul Huda, Norliza Julmohammad
• Format: Article
• Language: English; English
• Published: Penerbit UTM Press 2021
• Subjects: SB409-413 Culture of individual plants; TP200-248 Chemicals: Manufacture, use, etc.
• Online Access: https://eprints.ums.edu.my/id/eprint/36329/1/ABSTRACT.pdf; https://eprints.ums.edu.my/id/eprint/36329/2/FULL%20TEXT.pdf; https://eprints.ums.edu.my/id/eprint/36329/; https://doi.org/10.11113/jurnalteknologi.v83.15547

Thematuration stage of Cucumis sativusis among the important factors affecting its composition and quality.Hence,this study monitored the differences in total phenolic content (TPC), antioxidant activity, pigment and colourof Keningau-grown cucumbers (Cucumis sativusL.) at two stages of maturities, namely the semi-ripe(SR) and ripe (R). The colourimetricand spectroscopic findings revealed significant differences in the assessed variables (P < 0.05) in the two growth stages except for the pigment. The colourof semi-ripecucumbers was of lower L* (33.39 ± 4.26) and a* (-10.00 ± 1.74) mean values, while the ripe cucumbers registered the corresponding mean values of 36.71 ± 2.85 and -8.90 ± 1.85. R cucumbers gave a higher mean b* coordinate (16.38 ± 3.16) over the SR ones (14.52 ± 2.52). Compositions of pigments, namely, chlorophyll-a(SR: 4.86 ±0.01 µg/mL, R: 3.55 ± 0.00 µg/mL), chlorophyll-b(SR: 2.12 ± 0.02 µg/mL, R: 1.79, 0.02 µg/mL)andtotal chlorophyll were higher in SR (6.98 ±0.02µg/mL) than R( 5.34 ±0.02 µg/mL)cucumbers, except for the composition of carotenoids (SR: 0.82 ± 0.01 µg/mL, R: 1.78 ± 0.01 µg/mL). The TPC in SR was higher (424.21± 5.32 mg/g) than the R ones (185.51±4.62 mg/g), with the corresponding antioxidant activity (IC50) for SR and R at 157.98 ± 1.57 and 191.66 ± 2.58 µg/mL, respectively. TPC and antioxidant activity between the SR and R cucumbers were negatively correlated(-0.992), which meant that not all phenolic compounds wereinvolved in free radical scavenging.