Anthocyanin contributes more to hydrogen peroxide scavenging than other phenolics in apple peel

Chen

et al. 2014

Planta

Self Cite

Solar ultraviolet irradiation regulates anthocyanin synthesis in apple peel by modulating the production of reactive oxygen species via plasma membrane NADPH oxidase instead of other pathways. The synthesis of anthocyanin in apple peels is dependent upon solar irradiation. Using 3-mm commercial glass to attenuate solar UV-A and UV-B light, we confirmed that solar UV irradiation regulated anthocyanin synthesis in apple peels after exposing previously bagged fruit to sunlight. During sunlight exposure, UV attenuation did not affect the expression of MdHY5, MdCOP1, or MdCRY2, but significantly lowered plasma membrane NADPH oxidase activity and superoxide anion concentrations. UV attenuation also reduced the expression levels of MdMYB10, MdPAL, MdCHS, MdF3H, MdDFR, MdANS and MdUFGT1, UDP-glycose:flavonoid 3-O-glycosyltransferase (UFGT) activity, and local concentrations of anthocyanin and quercetin-3-glycoside. In contrast, exogenous application of hydrogen peroxide could enhance anthocyanin and quercetin-3-glycoside synthesis. Xanthophyll cycle pool size on a chlorophyll basis was higher but its de-epoxidation was lower under direct sunlight irradiation than that under UV-attenuating conditions. This suggests that reactive oxygen species (ROS) produced in chloroplast are not major contributors to anthocyanin synthesis regulation. Inhibition of plasma membrane NADPH oxidase activity lowered the production of ROS through this mechanism, significantly inhibited the synthesis of anthocyanin, and increased the total production of ROS in apple peel under direct sunlight irradiation, suggesting that ROS produced via plasma membrane NADPH oxidase regulates anthocyanin synthesis. In summary, solar UV irradiation regulated anthocyanin synthesis in apple peels by modulating the production of ROS via plasma membrane NADPH oxidase.

Section: Discussionsupporting

confidence: 90%

Section: Discussionmentioning

confidence: 81%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Reactive oxygen species produced via plasma membrane NADPH oxidase regulate anthocyanin synthesis in apple peel

Chen

et al. 2014

Planta

Self Cite

“…Currently, red-fleshed apples are receiving increased attention because of their remarkable anthocyanin contents, as it has been reported that anthocyanin contributes more to hydrogen peroxide scavenging than other phenolic compounds in the apple peel 3 , and they are very important natural flavonoid compounds for the apple colour.…”

mentioning

confidence: 99%

Untitled

2017

IJPSR

Apples are rich of vital components to the human health, such as the amino acids, but their presence differ according to the type and colour of the apples. In this study we compared the concentrations of amino acids in the peels and pulps of red and green apples, by using the HLPC for analysis. 16 amino acids were found with different concentrations according to the locality in which they exist in the red and green apples cultivars. The content of amino acids in the pulps was found higher than in the peels in both the red and green apples cultivars. The content of amino acids in the green apples recorded higher value than in the red apples. Higher concentrations of Aspartic acid were found in the peels and pulps of the red and green apples while the content of Methionine acid decreased, which was considered as the lowest amino acid found in the two apples cultivars and Histidine amino acid was not detected in both red and green apples cultivars.

Synthesis, In Vitro Biological Evaluation and In Silico Studies of Some New Heterocyclic Schiff Bases

et al. 2018

2‐Hydroxy‐naphthaldehyde based heterocyclic Schiff base derivatives (1 a‐1 h) were prepared and characterized by multi‐spectroscopic techniques and elemental analysis. Antibacterial activity of all the compounds was tested against Streptococcus pneumoniae, Enterococcus faecalis, Pseudomonas aeruginosa, Salmonella enterica, Klebsiella pneumoniae and Escherichia coli bacterial strains. The antifungal potential of the synthesized compounds was also tested against three Candida strains (Candida albicans, Candida glabrata and Candida tropicalis). In the antibacterial activity, the compounds showed high MIC values and thus found less potent against all the tested bacterial strains. Interestingly, compounds 1 b and 1 c exhibited significant activity with MIC 125 μg/ml against all the tested fungal strains. Hemolytic assay against human RBCs revealed that compounds 1 b and 1 c showed less toxicity than the standard drug fluconazole at each tested concentration (25‐1000 μg/ml). In growth kinetics studies, compounds 1 b and 1 c significantly inhibited the growth of Candida cells at 2MIC and MIC concentrations. The interaction ability of lead compounds (1 b and 1 c) with Ct–DNA was carried out by absorption, fluorescence, hydrodynamic, cyclic voltammetery measurements and circular dichroism. Results suggested that compound 1 b and 1 c bind to Ct–DNA via an intercalative mode supported by molecular docking studies. The antioxidant potential of heterocyclic derivatives 1 b and 1 c was estimated by DPPH free radical and hydrogen peroxide assay which confirm that compounds exhibited significant antioxidant activity.