Phytochemical changes in mango fruit in response to Alternaria alternata infection

Abstract

Changes in mango fruit quality, malondialdehyde content, and enzymatic activities in response to pathogen Alternaria alternata infection were studied. A. alternata significantly affected the appearance of mango fruit at 5 and 7 days after treatment (DAT). The quality of pathogen-infected fruit first showed a significant decrease in titratable acidity and vitamin C content and a significant increase in pH since 3 DAT. The malondialdehyde content was higher than that in the untreated controls at 3 and 7 DAT. The enzyme activities of ascorbate peroxidase and polyphenol oxidase showed significant increases since 3 DAT. Significant increases in l-phenylalanine ammonia-lyase and superoxide dismutase activities were observed at 7 DAT. These results indicate that A. alternata infection first significantly affects some biochemical constituents and enzyme activities in mango fruit since 3 DAT and that there was no significant effect on appearance until 5 DAT.

Antioxidant response of sweet pepper fruits infected with Alternaria alternata

“…33 The activity of CAT was lower in inoculated fruits of Una and Kurtovska kapia than in control fruits. This is consistent with the results of Li et al 34 who found decrease in CAT activity in mango fruits infected by A. alternata. However, water-injected fruits of Kurtovska kapia showed the highest CAT activity.…”

“…4). Obtained results are in agreement with those of Li et al 34 who reported an increase in MDA concentration in mango fruits infected by A. alternata. To observe the relationship among examined bioactive compounds, enzyme activity, genotypes and wounding and infection stress, principal component analysis (PCA) (Fig.…”

Effect of Storage Conditions on Antioxidant Enzymes and Polyphenol Oxidase Activity of African Star Apple Juice

“…SOD is a metalloenzyme that catalyzes the dismutation of superoxide anion to oxygen and H2O2 thus, protecting plant tissues from oxidation of lipids and DNA damages (Badejo et al, 2016). It is the first defense mechanism that converts free oxygen radicals O2 to H2O2 to scavenge other free radicals (Li et al, 2018). The observed increase as storage period increased is in conjunction with the findings of Razavi et al (2018) in stored peach fruits at 1 o C for 2-4 weeks.…”

Stress Response to Climate Change and Postharvest Handling in Two Differently Pigmented Lettuce Genotypes: Impact on Alternaria alternata Invasion and Mycotoxin Production

“…Possible strategies to limit Alternaria infection include: (1) obtaining resistant cultivars in breeding programs. In this regard, the studies conducted so far point to the plant’s ability to increase phenolic compounds and its antioxidant metabolism as good traits to select for [ 33 , 34 , 35 ]; (2) selecting adequate cultivation and field management techniques in order to reduce fungi invasion [ 14 , 36 ]. Cultivation practices, such as maintaining a healthy field and crop vigor and removing infected plant debris, are helpful in controlling fungi invasion, but are not always sufficient; (3) improving postharvest handling, since vegetables can also be contaminated by A. alternata mycotoxins during this period [ 37 ].…”