Improving the Berry Quality and Antioxidant Potential of Flame Seedless Grapes by Foliar Application of Chitosan–Phenylalanine Nanocomposites (CS–Phe NCs)

Abstract

The production and sustainability of grape berries with high quality and health-promoting properties is a major goal. In this regard, nano-engineered materials are being used for improving the quality and marketability of berries. In this study, we investigated the potential role of chitosan–phenylalanine nanocomposites (CS–Phe NCs) in improving the quality of Flame Seedless (Vitis vinifera L.) grape berries, such as titratable acidity (TA), pH, total soluble solids (TSS), ascorbic acid, total phenolics, total flavonoids, anthocyanin, 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging activity, and phenylalanine ammonia-lyase (PAL) activity. In this context, grape berries collected in two growing seasons (2018–2019) were screened. Regarding the experimental design, the treatments included chitosan at a 0.5% concentration (CS 0.5%), phenylalanine at 5 mM and 10 mM concentrations (Phe 5 mM and Phe 10 mM), and chitosan–phenylalanine nanocomposites (CS–Phe NCs) at 5 mM and 10 mM concentrations. The lowest TA was recorded in grape berries treated with CS–Phe NCs with a 10 mM concentration. However, treatments enhanced with TSS, which reached the highest value with 10 mM of CS–Phe NCs, were reflected as the highest ratio of TSS/TA with 10 mM of CS–Phe NC treatment. Nanocomposites (NCs) also increased pH values in both study years compared to the control. Similarly, the ascorbic acid and total phenolic content increased in response to NP treatment, reaching the highest value with 5 mM and 10 mM of CS–Phe NCs in 2018 and 2019, respectively. The highest flavonoid content was observed with 5 mM of CS–Phe NCs in both study years. In addition, the anthocyanin content increased with 5 and 10 mM of CS–Phe NCs. PAL activity was found to be the highest with 5 mM of CS–Phe NCs in both study years. In addition, in accordance with the increase in PAL activity, increased total phenolics and anthocyanin, and higher DPPH radical scavenging activity of the grapes were recorded with the treatments compared to the control. As deduced from the findings, the coating substantially influenced the metabolic pathway, and the subsequent alterations induced by the treatments were notably appreciated due to there being no adverse impacts perceived.

Postharvest chitosan-arginine nanoparticles application ameliorates chilling injury in plum fruit during cold storage by enhancing ROS scavenging system activity

“…In this sense, Sohail et al [22] reported that postharvest Arg treatment prevented postharvest senescence of broccoli by reducing the ascorbic acid content and enhancing the antioxidant capacity. Likewise, the foliar application of CTS-phenylalanine nanocomposites at 5 mM concentration enhanced ascorbic acid content in grape fruit [52]. Babalar et al [24] reported that the higher ascorbic acid accumulation in pomegranate fruit treated with arginine resulted from higher GR/ APX system activity or lower AAO enzyme activity and remarkably assisted to increasing the antioxidant capacity of fruits during cold storage at 4 °C for 60 days.…”

Application of chitosan nanoparticles in quality and preservation of postharvest fruits and vegetables: A review

“…Similarly, several reports described the synthesis of CHNPs with a size of 50−100 nm using the same procedure (Abdel‐Rahman et al., 2021; Karimirad et al., 2019; Mohammadi et al., 2015a; Valizadeh et al., 2021). The ionic gelation method allowed the formation of CHNPs with spherical shapes (Figure 1b) (Gohari et al., 2021; Karimirad et al., 2018; Lustriane et al., 2018). On the other hand, a few reports used the nanoprecipitation method using a peristaltic pump for the preparation of the CHNPs (Hernandez‐Lopez et al., 2020).…”

“…(a) Transmission electron microscopy (TEM) images and size distribution of CHNPs synthesized using the ionic gelation method (Cuong et al., 2022). (b) Scanning electron microscopy (SEM) and TEM analyses of chitosan–phenylalanine NPs (Gohari et al., 2021). (c) TEM images of CHNPs and starch/CHNPs films (Shapi'i et al., 2020).…”

“…As mentioned above, the nanoprecipitation method generally allowed the synthesis of smaller CHNPs (<50 nm in diameter) than the ionic gelation method (>50 nm in diameter). Most reports indicated the average diameter of the CHNPs; however, the CHNPs diameter varied providing a size distribution that was calculated using scanning electron or transmission electron microscopy (Figure 1b) (Cuong et al., 2022; Gohari et al., 2021).…”

Physico-Chemical Properties Prediction of Flame Seedless Grape Berries Using an Artificial Neural Network Model

“…In Egypt, it is ranked second after citrus fruits, due to its high net return; it is grown rapidly, especially in reclaimed soils [ 6 , 7 ]. Due to the availability of antioxidants, minerals (such as calcium, magnesium, and iron), soluble sugars, anthocyanins, flavonoids, organic acids, vitamins (such as B1, B2, and C), and aromatic compounds, the grapevine is one of the most economically significant sources for the human health and food industries [ 8 , 9 , 10 , 11 ]. Furthermore, the grapevine has rich phenolic compounds, so it has positive health effects on people to protect them from different diseases [ 12 , 13 , 14 , 15 , 16 ].…”