Anti-tyrosinase kinetics and antibacterial process of caffeic acid N-nonyl ester in Chinese Olive (Canarium album) postharvest

Abstract

Enzymatic browning and bacterial putrefaction are mainly responsible for quality losses of Chinese Olive (Canarium album) postharvest and lead to very short shelf life on average. Screening anti-browning and anti-bacterial agents is important for preservation of Chinese Olive. Caffeic acid N-nonyl ester (C-9) and caffeic acid N- Heptyl ester (C-7) was synthesized as inhibitors of tyrosinase, which is a key enzyme in browning process. The compound of C-9 could inhibit the activity of tyrosinase strongly and its IC50 value was determined to be 37.5μM, while the compound of C-7 had no inhibitory ability. Kinetic analyses showed that compound of C-9 has been a reversible inhibitory mechanism below 50μM and been irreversible mechanisms above 50μM. For the reversible inhibitory mechanism, the values of inhibitory constants (KI and KIS) were determined to be 24.6 and 37.4μM, respectively. The results of Chinese Olive fruit postharvest showed that the compound of C-9 could effectively anti-browning and anti-bacterial putrefaction. In addition, this compound had strong antibacterial activities against Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Salmonella. Therefore, C-9 could be a potential anti-browning and anti-bacterial reagent.

Synthesis and Studies of the Inhibitory Effect of Hydroxylated Phenylpropanoids and Biphenols Derivatives on Tyrosinase and Laccase Enzymes

“…The decrease in the intensity of the o-quinone band (Figure S2) was likely due to the reaction of the o-quinone moiety with either the amino group of dopamine (intramolecular reaction) or reactive groups (amino, hydroxyl, thiol) present on the surface of the enzyme. This behavior has been described for analogs of caffeic acid, which at high concentrations act as irreversible (suicide) inhibitors of tyrosinase due to the high reactivity of the corresponding o-quinone [57,58]. Compounds 8, 9, 17 and 20 manifested a selectivity towards the diphenolasic phase probably due to a restricted molecular volume, high structural flexibility and antioxidant activity which together may provide strong interactions with the amino acids residues or with the substrate dopamine.…”

Precise Species Detection in Traditional Herbal Patent Medicine, Qingguo Wan, Using Shotgun Metabarcoding

“…It eliminates pharyngeal pain, reducing swelling and relieving pain ( Commission, 2020 ). Several studies have shown that the chemical ingredients in Qingguo Wan prescriptions exhibit excellent anti-inflammatory effects ( Shen et al, 2003 ; Geng et al, 2011 ; Zhang, 2012 ; Jia et al, 2016 ; Nikzad-Langerodi et al, 2017 ). Of these, Canarii Fructus represents the primary curative ingredient in relieving throat pain, while displaying various pharmacological activities that include antibacterial and anti-inflammatory properties.…”

“…Of these, Canarii Fructus represents the primary curative ingredient in relieving throat pain, while displaying various pharmacological activities that include antibacterial and anti-inflammatory properties. Furthermore, it has an excellent therapeutic effect on acute pharyngitis ( Geng et al, 2011 ; Jia et al, 2016 ). Baicalin is a compound obtained from Scutellariae Radix, denoting the main anti-inflammatory ingredient ( Shen et al, 2003 ; Zhang, 2012 ).…”

De novo transcriptome assembly and comparative transcriptomic analysis provide molecular insights into low temperature stress response of Canarium album

“…album , has been proved to have radical scavenging capabilities 15 and the ethyl acetate and ellagic acid, found in it, can be used for anti-HIV and anti-hepatitis B virus remedies 16 , 17 . Moreover, C. album is also a source of caffeic acid N-nonyl ester showing good anti-bacterial characteristics 18 .…”