Metabolomic and Transcriptomic Analysis of the Anthocyanin Regulatory Networks in Malus Domestica Borkh. Peel with Different Color Patterns

Background:Coloring is an important external quality of ‘Fuji’ apple (Malus domestica Borkh.) and there are two color patterns of apple peels, i.e., stripe and blush. The objectives of this study were to reveal the anthocyanin biosynthesis metabolic pathway in striped and blushed peels of Malus domestica using metabolomics and transcriptomics, to identify different anthocyanin metabolites, and to analyze the differentially expressed genes involved in anthocyanin biosynthesis.Result:The metabolite concentration and gene expression were profiled in the striped and blushed fruit peels of apple harvested at three ripening periods to elucidate the color formation mechanism. At the green fruit period, there were 83 DAMs,including 30 flavonoids, 674 DEGs (521 up-regulated and 153 down-regulated),including 3 MYB related genes (up-regulated, LOC103415449, LOC103421948, LOC103432338) and 2 bHLH genes(up-regulated, LOC103436250, LOC103437863) between striped and blushed apple.At the color turning period, there were 48 DAMs,including 20 flavonoids, 880 DEGs (274 up-regulated and 606 down-regulated), including 3 differentially expressed E2.3.1.133, HCT genes(down-regulated), 2 differentially expressed F3H genes (down-regulated), 1 differentially expressed BZ1 gene (down-regulated) and 2 differentially expressed ANS genes (up-regulated) and 2 up-regulated MYB related genes (LOC103411576, LOC103412495), 5 down-regulated MYB related genes(LOC103400953, LOC103408672, LOC103415404, LOC103420697, LOC103421948), 1 differentially expressed bHLH gene(down-regulated, LOC103400870). At the complete coloring period，there were 95 DAMs,including 34 flavonoids, 2258 DEGs (1159 up- and 1099 down-regulated), including 3 differentially expressed E2.3.1.133, HCT genes(down-regulated), 1 differentially expressed E2.3.1.133, HCT genes(up-regulated), 2 differentially expressed CYP98A genes (up-regulated), 4 differentially expressed CHS genes (up-regulated), 2 differentially expressed E5.5.1.6 genes(up-regulated), 2 differentially expressed CYP75B1 genes (up-regulated), 2 differentially expressed F3R genes (up-regulated), 2 differentially expressed ANS genes (up-regulated), 1 differentially expressed DFR genes (up-regulated), 2 differentially expressed BZ1 genes (up-regulated) and 1 differentially expressed MYB related gene (up-regulated, LOC103401575) .There were both 10 kinds of cyanidin in apple peel at color turning period and complete coloring period, Keracyanin and Cyanin were up-regulated at color turning period and Cyanidin-3-O-(6''-O-malonyl)glucoside was up-regulated at complete coloring period.Conclusions: Our researches provide important information on the anthocyanin metabolites and the candidate genes involved in the anthocyanin biosynthesis pathways of Fuji apple in M.domestcia.

The Endophytic Strain Trichoderma asperellum 6S-2: An Efficient Biocontrol Agent against Apple Replant Disease in China and a Potential Plant-Growth-Promoting Fungus

A study was conducted for endophytic antagonistic fungi obtained from the roots of healthy apple trees growing in nine replanted orchards in Shandong Province, China. The fungi were assessed for their ability to inhibit Fusarium proliferatum f. sp. malus domestica MR5, a fungal strain associated with apple replant disease (ARD). An effective endophyte, designated as strain 6S-2, was isolated and identified as Trichoderma asperellum. Strain 6S-2 demonstrated protease, amylase, cellulase, and laccase activities, which are important for the parasitic and antagonistic functions of pathogenic fungi. The inhibition rate of 6S-2 against Fusarium proliferatum f. sp. malus domestica MR5 was 52.41%. Strain 6S-2 also secreted iron carriers, auxin, ammonia and was able to solubilize phosphorus. Its fermentation extract and volatile substances inhibited the growth of MR5, causing its hyphae to twist, shrink, swell, and rupture. The antifungal activity of the 6S-2 fermentation extract increased with increasing concentrations. It promoted the production and elongation of Arabidopsis thaliana lateral roots, and the strongest effects were seen at a concentration of 50 mg/mL. A GC-MS analysis of the 6S-2 fermentation extract and volatile substances showed that they comprised mainly alkanes, alcohols, and furanones, as well as the specific volatile substance 6-PP. The application of 6S-2 spore suspension to replanted apple orchard soils reduced plant oxidative damage and promoted plant growth in a pot experiment. Therefore, the endophytic strain T. asperellum 6S-2 has the potential to serve as an effective biocontrol fungus for the prevention of ARD in China, and appears to promote plant growth.

Exploring the Efficacy of Aqueous Extracts of Malus domestica var Anna, Prunus persica, Ricinus Communis and Carica papaya Against Pathogenic Bacterial Strains

Medicinal plants have antibacterial, antifungal and antiviral activities. More or less all plants have medicinal properties. In this research article, we have selected four economically important plants (three fruit plants and an economically important plant), Malus domestica Borkh., Prunus persica L., Ricinus communis L., and Carica papaya L. found in several areas of Indian state Uttarakhand. Using the methanolic extract of leaves, we have screened those four plants against four human pathogenic bacteria, Escherichia coli, Streptococcus pneumoniae, Staphylococcus aureus and Micrococcus luteus. For our experiment we have screened the methanolic leaf extracts of four plants against the above-mentioned bacteria. Statistical analysis was also performed for validation. Result revealed the said bacteria have potential antibacterial activities. So, these leaves can be used for clinical trial. These plants can also be used for making herbal medicines.

HRMS Characterization, Antioxidant and Cytotoxic Activities of Polyphenols in Malus domestica Cultivars from Costa Rica

There is increasing interest in research into fruits as sources of secondary metabolites because of their potential bioactivities. In this study, the phenolic profiles of Malus domestica Anna and Jonagold cultivars from Costa Rica were determined by Ultra Performance Liquid Chromatography coupled with High Resolution Mass Spectrometry (HRMS) using a quadrupole-time-of-flight analyzer (UPLC-QTOF-ESI MS), on enriched-phenolic extracts from skins and flesh, obtained through Pressurized Liquid Extraction (PLE). In total, 48 different phenolic compounds were identified in the skin and flesh extracts, comprising 17 flavan-3-ols, 12 flavonoids, 4 chalcones, 1 glycosylated isoprenoid and 14 hydroxycinnamic acids and derivatives. Among extracts, the flesh of Jonagold exhibits a larger number of polyphenols and is especially rich in procyanidin trimers, tetramers and pentamers. Evaluating total phenolic content (TPC) and antioxidant activities using ORAC and DPPH procedures yields higher values for this extract (608.8 mg GAE/g extract; 14.80 mmol TE/g extract and IC50 = 3.96 µg/mL, respectively). In addition, cytotoxicity evaluated against SW620 colon cancer cell lines and AGS gastric cancer cell lines also delivered better effects for Jonagold flesh (IC50 = 62.4 and 60.0 µg/mL, respectively). In addition, a significant negative correlation (p < 0.05) was found between TPC and cytotoxicity values against SW620 and AGS adenocarcinoma (r = −0.908, and −0.902, respectively). Furthermore, a significant negative correlation (p < 0.05) was also found between the number of procyanidins and both antioxidant activities and cytotoxicity towards SW620 (r = −0.978) and AGS (r = −0.894) cell lines. These results align with Jonagold flesh exhibiting the highest abundance in procyanidin oligomers and yielding better cytotoxic and antioxidant results. In sum, our findings suggest the need for further studies on these Costa Rican apple extracts—and particularly on the extracts from Jonagold flesh—to increase the knowledge on their potential benefits for health.