ABSTRACT
The red flesh coloration of apples is a result of a biochemical pathway involved in the biosynthesis of anthocyanins and anthocyanidins. Based on apple genome analysis, a high number of regulatory genes, mainly transcription factors such as MYB, which are components of regulatory complex MYB-bHLH-WD40, and several structural genes (PAL, 4CL, CHS, CHI, F3H, DFR, ANS, UFGT) involved in anthocyanin biosynthesis, have been identified. In this study, we investigated novel genes related to the red-flesh apple phenotype. These genes could be deemed molecular markers for the early selection of new apple cultivars. Based on a comparative transcriptome analysis of apples with different fruit-flesh coloration, we successfully identified and characterized ten potential genes from the plant hormone transduction pathway of auxin (GH3); cytokinins (B-ARR); gibberellins (DELLA); abscisic acid (SnRK2 and ABF); brassinosteroids (BRI1, BZR1 and TCH4); jasmonic acid (MYC2); and salicylic acid (NPR1). An analysis of expression profiles was performed in immature and ripe fruits of red-fleshed cultivars. We have uncovered genes mediating the regulation of abscisic acid, salicylic acid, cytokinin, and jasmonic acid signaling and described their role in anthocyanin biosynthesis, accumulation, and degradation. The presented results underline the relationship between genes from the hormone signal transduction pathway and UFGT genes, which are directly responsible for anthocyanin color transformation as well as anthocyanin accumulation during apple-fruit ripening.
Subject(s)
Cyclopentanes , Malus , Oxylipins , Malus/genetics , Malus/metabolism , Fruit/genetics , Fruit/metabolism , Anthocyanins/metabolism , Gene Expression Profiling/methods , Transcriptome , Abscisic Acid/metabolism , Gene Expression Regulation, Plant , Plant Proteins/metabolismABSTRACT
Consuming food that is rich in antioxidants reduces the risk of developing chronic diseases and oxidative stress. Fruits and vegetables are an excellent source of substances with antioxidant and pro-health properties. Such raw materials, characterized by a high content of polyphenolic compounds and antioxidant capacity, include pear fruits. In this study, the concentrations of bioactive compounds, as well as the antioxidant, anti-inflammatory, and antiproliferative activity in fruits of five selected pear cultivars were determined and compared. LC-MS and UPLC-PDA methods were used to determine the polyphenolic, carotenoid, chlorophyll, and triterpenoid profiles and content, and the antioxidant activity was analyzed using DPPH and ferric-reducing ability of plasma (FRAP) tests. The anti-inflammatory activity was determined against COX-1 and COX-2 enzymes. The cytotoxic activity of the test compounds was assessed against six tumor cell lines. The results showed that the major group of phenolic compounds in all cultivars was phenolic acids. In the group of chromoplastic pigments, chlorophyllide a and 9-cis-ß-carotene were the major compounds, while in the triterpene group, ursolic acid was dominant. The antioxidant potential correlated with the content of polyphenols and carotenoids, and was the strongest for the 'Radana' cultivar. The highest antiproliferative activity in all varieties was established for bladder cancer.
