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
• Institution: Universiti Malaysia Sabah

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.