Purification and characterization of polyphenol oxidase from fresh ginseng

Abstract

Polyphenol oxidase (PPO) was purified from fresh ginseng roots using acetone precipitation, carboxymethyl (CM)-Sepharose chromatography, and phenyl-Sepharose chromatography. Two isoenzymes (PPO 1 and PPO 2) were separated using an ion-exchange column with CM-Sepharose. PPO 1 was purified up to 13.2-fold with a 22.6% yield. PPO 2 bound to CM-Sepharose, eluted with NaCl, and was purified up to 22.5-fold with a 17.4% yield. PPO 2 was further chromatographed on phenyl-Sepharose. The molecular weight of the purified PPO 2 from fresh ginseng was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and was about 40 kDa. The optimum temperature and pH were 20℃ and 7.0, respectively, using catechol as a substrate. Pyrogallol showed the highest substrate specificity. The effect of a PPO inhibitor showed that its activity increased slightly in the presence of a low concentration of citric acid. High concentrations of acidic compounds and sulfite agents significantly inhibited purified ginseng PPO 2.

Purification, kinetic parameters, and isoforms of polyphenol oxidase from “Xushu 22” sweet potato skin

“…In contrast, the yield of sPPO2 was 2.10%, and the sPPO2 specific activity was 53,463.16 U/mg. Compared to previous literature reports, the fold-purification was 5.14 higher than reported for the PPO from potato (Aksoy, 2020), 19.77-fold higher than for the PPO from tea leaf (Camellia sinensis) (Öztürk, Aksoy, & Küfrevioğlu, 2019), 13.3 and 22.5 than for the PPO from Ginseng (Kim & Kim, 2013), and 12.38 higher than for the PPO from Indian pink guava (Vishwasrao & Ananthanarayan, 2018). The recovery rate was higher than for the PPO from mamey fruit (Pouteria sapota) which was 0.28% (Orozcoa, Moreno, Álvarez, Sampedrob, & Nájerac, 2011) and close to the recovery rate of 2.03% seen for the PPO from chestnut kernel (Gong, Li, Liu, Cheng, & Wang, 2015)…”

Inhibitory effect of chemical and natural anti-browning agents on polyphenol oxidase from ginger (Zingiber officinale Roscoe)

“…The initial velocity was calculated from the slope of the absorbance value against time curve. One unit (U) of PPO activity was defined as amount of enzyme that caused a 0.001 absorbance change per min (Kim and Kim 2013).…”

Biochemical Properties of Emir Grape Polyphenol Oxidase as Affected by Harvest Year

“…Voss], it was found that L-cysteine showed the best inhibitory effect, with an IC50 of 1.3±0.002 mM followed by ascorbic acid (1.5 ± 0.06 mM), glutathione (1.5 ±0.07 mM), EDTA (100 ±0.02 mM) and citric acid (186±0.16 mM). It was reported that Ginseng PPO activity was inhibited by ascorbic acid, sodium metabisulfite, and kojic acid, using catechol as the substrate, whereas 1 mM citric acid showed slight activation rather than inhibition for the ginseng PPO [18]. …”