The Combined Effect of Hot Water Treatment and Chitosan Coating on Mango (Mangifera indica L. cv. Kent) Fruits to Control Postharvest Deterioration and Increase Fruit Quality

The synergistic effect of dipping in 55 °C for 5 min of hot water (HW) and 1% chitosan coating during the storage of mango at 13 ± 0.5 °C and 85%–90% relative humidity for 28 days was investigated. The combined treatment significantly suppressed the fruit decay percentage compared with both the single treatment and the control. In addition, the specific activities of key plant defense-related enzymes, including peroxidase (POD) and catalase (CAT), markedly increased. The increase occurred in the pulp of the fruits treated with the combined treatment compared to those treated with HW or chitosan alone. While the control fruits showed the lowest values, the combination of pre-storage HW treatment and chitosan coating maintained higher values of flesh hue angle (h°), vitamin C content, membrane stability index (MSI) percentage, as well as lower weight loss compared with the untreated mango fruits. The combined treatment and chitosan treatment alone delayed fruit ripening by keeping fruit firmness, lessening the continuous increase of total soluble solids (TSS), and slowing the decrease in titratable acidity (TA). The results showed that the combined application of HW treatment and chitosan coating can be used as an effective strategy to suppress postharvest decay and improve the quality of mango fruits.

Effects of Essential Oils on Post Harvest Quality and Shelf Life of Mango (Mangifera Indica L.)

Effects of essential oils, namely Cinnamon, Citronella, Peppermint, Eucalyptus, Lavender, Thyme, Rosemary, Basil oil enriched coconut oil emulsion on shelf life and quality of ambient stored mango cv. Rangkuai were evaluated. Citronella oil (Cymbopogon nardus) @ 0.5% (v/v) was found to maintain low weight loss (5.14%), high fruit firmness (52.85 N/cm2), ascorbic acid (33.62 mg/100 g), total phenol (89.67 mg/100 g) and least fruit decay (8.33%) at 12 days after storage (DAS) and had delayed accumulation of pulp colour (L: 91.06, a: -2.61, b : 24.03), β-carotene (3.85 mg/100 g) and total sugar (4.46%) for delayed ripening, thus found to extend the shelf life by 7 days compared with control (12.85 days). Bangladesh J. Bot. 50(4): 1143-1149, 2021 (December)

Enhancement of Biocontrol Efficacy of Pichia kudriavzevii Induced by Ca Ascorbate against Botrytis cinerea in Cherry Tomato Fruit and the Possible Mechanisms of Action

Antagonistic yeast is a promising way to control postharvest fruit decay because of its safety and broad-spectrum resistance. However, the biocontrol efficacy of yeast is limited by environmental stress, such as oxidative stress.

Effect of packaging material and postharvest calcium treatment on weight loss, decay and biochemical quality of strawberry fruits during storage

Strawberry (Fragaria x ananassa Duch.) fruits are highly perishable which lose their marketability within a short period of time, resulting in considerable loss of fruits after harvest. In present study, the packaging materials treatment i.e. polypropylene terephthalate (PET) Punnet and High density polythene (HDPE) crates and calcium compounds (CaCl2 and Ca(No3)2) were examined for the storability and biochemical quality of strawberry (cv. Winter Down) fruits in cold condition (3±1 °C) in comparison to the untreated control fruit in ambient storage for 3, 6 and 8 days storage period. Results revealed that physiological loss in weight (PLW) and fruit decay increased with the advancement of the storage period irrespective of the treatments. Fruits treated with CaCl2 (2%), packed in PET Punnets and stored in cold condition (3±1 °C) showed significantly minimum PLW (6.55, 11.12 and 15 34 %) and fruit decay (7.29, 17.71 and 34.38 %) at 3, 6 and 8 days storage, respectively. Non-treated control fruits at ambient conditions could not maintain their marketability even 3 days of storage and showed relatively high decay losses (25.00, 62.21 and 91.67 % at 3, 6 and 8 days of storage, respectively). Packaging and calcium treatment did not affect the fruit total soluble solids (TSS) and total sugars but was found effective to slow down the decrease of ascorbic acid and acidity contents of the fruit during storage. PET Punnets packaged fruits treated with CaCl2 (2%) under cold conditions retained better shelf-life with better biochemical quality of fruits during storage while untreated control fruits deteriorated rapidly.

Impact of Chitosan, Sucrose, Glucose, and Fructose on the Postharvest Decay, Quality, Enzyme Activity, and Defense-Related Gene Expression of Strawberries

Strawberry is one of the most highly consumed fruits worldwide, but is extremely perishable. This study systematically compared the effects of chitosan, sucrose, glucose, and fructose immersion on the physiology and disease development in harvested strawberries. After storage at 15 °C for 9 days, all sugar treatment groups had significantly higher total soluble solids and total anthocyanin content than those of the control group. All sugar treatment groups inhibited malondialdehyde accumulation. At the end of the storage, chitosan, glucose, and fructose maintained higher superoxide dismutase activity and chitosan maintained higher catalase activity. The chitosan and glucose groups had lowest fruit decay index, followed by sucrose and fructose groups. The fruit firmness and luster were better maintained in the glucose group. Furthermore, genes related to sucrose metabolism (e.g., FaSUS1 and FaSUS2), titratable acidity accumulation (e.g., FaMDH1, FaMDH2, FaCS1, and FaCS2), disease resistance (e.g., FaPGIP1, FaWRKY1, and FaWRKY33) and to anabolic jasmonic acid and abscisic acid pathways (e.g., FaJAZ1, FaJAZ2, FaOPR3, FaNCED1, and FaNCED2) were regulated to varying degrees, suggesting that chitosan and glucose participate in plants’ immune signaling networks and regulate disease resistance in fruit through hormone pathways. The findings provide new insights into the physiological regulation of harvested strawberries.

Diversity of Botryosphaeriaceae and Diaporthe species associated with postharvest apple fruit decay in Serbia

Family Botryosphaeriaceae and the genus Diaporthe (fam. Diaporthaceae) represent diverse groups of plant pathogens, which include causal agents of leaf spot, shoot blight, branch and stem cankers, dieback, and pre and postharvest apple fruit decay. Apple fruit with the symptoms of light to dark brown decay were collected during and after harvest from 2016 to 2018. Thirty selected isolates, which pathogenicity was confirmed, were identified and characterized based on multilocus phylogeny and morphology. Five species from the family Botryosphaeriaceae and two from the genus Diaporthe (fam. Diaporthaceae) were discovered. The most commonly isolated was Diplodia seriata followed by Botryosphaeria dothidea. In this work, Diaporthe rudis is described as a new postharvest pathogen of apple fruit. Diplodia bulgarica, Diplodia sapinea, Neofusicoccum yunnanense, and Diaporthe eres are initially described as postharvest apple and D. sapinea as postharvest quince and medlar fruit pathogens in Serbia. As species of the family Botryosphaeriaceae and the genus Diaporthe are known to cause other diseases on their hosts, have an endophytic nature, and a wide host range, findings from this study imply that they may become a new challenge for successful fruit production.

Maintenance of Postharvest Quality and Reactive Oxygen Species Homeostasis of Pitaya Fruit by Essential Oil p-Anisaldehyde Treatment

The performance of p-Anisaldehyde (PAA) for preserving pitaya fruit quality and the underpinning regulatory mechanism were investigated in this study. Results showed that PAA treatment significantly reduced fruit decay, weight loss and loss of firmness, and maintained higher content of total soluble solids, betacyanins, betaxanthins, total phenolics and flavonoids in postharvest pitaya fruits. Compared with control, the increase in hydrogen peroxide (H2O2) content and superoxide anion (O2•−) production was inhibited in fruit treated with PAA. Meanwhile, PAA significantly improved the activity of antioxidant enzymes superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT). Moreover, PAA-treated pitaya fruit maintained higher ascorbic acid (AsA) and reduced-glutathione (GSH) content but lower dehydroascorbate (DHA) and oxidized glutathione (GSSG) content, thus sustaining higher ratio of AsA/DHA and GSH/GSSG. In addition, activities of ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase (MDHAR) and dehydrogenation ascorbic acid reductase (DHAR), as well as the expression of HpSOD, HpPOD, HpCAT, HpAPX, HpGR, HpDHAR and HpMDHAR, were enhanced after PAA treatment. The findings suggest that postharvest application of PAA may be a reliable method to control postharvest decay and preserve quality of harvested pitaya fruit by enhancing the antioxidant potential of the AsA-GSH cycle and activating an antioxidant defense system to alleviate reactive oxygen species (ROS) accumulation.

Salicylic Acid Alleviates Postharvest Fruit Decay of Strawberry (Fragaria x ananassa Duch.-A Review

Strawberry (Fragaria x ananassa Duch.) fruits are highly perishable and fruit quality decrease rapidly after harvesting, thereby it has a limited scope of long duration storage. Among several synthetic chemicals suggested for minimizing postharvest losses of fruits, Salicylic acid (SA) is a natural phenolic compound widely distributed in plants and considered as a hormone because of its regulatory role in plants. Salicylic acid has received particular attention because of its role in the modulation of the plant response to biotic and abiotic stresses. Current scientific knowledge on the salicylic acid application in postharvest management of strawberry fruits suggests that SA has a potential role in minimizing fruit decay and maintaining fruit quality. These predictors, however, need further work to validate reliability in postharvest management of strawberry fruits in a larger perspective.

Dynamic Microbiome Changes Reveal the Effect of 1-Methylcyclopropene Treatment on Reducing Post-harvest Fruit Decay in “Doyenne du Comice” Pear

Pathogen-induced decay is one of the most common causes of fruit loss, resulting in substantial economic loss and posing a health risk to humans. As an ethylene action inhibitor, 1-methylcyclopropene (1-MCP) can significantly reduce fruit decay, but its effect on fruit pathogens remains unclear. Herein, the change in microbial community structure was analyzed using the high-throughput sequencing technology, and characteristics related to fruit quality were determined after 1-MCP (1.0 M l L–1) treatment in “Doyenne du Comiceis” pear fruit during storage at ambient temperature. Overall, 1-MCP was highly effective in reducing disease incidence and induced multiple changes of the fungal and bacterial microbiota. At day 15, the microbial diversity of fungi or bacteria was reduced significantly in the control fruit (non-treated with 1-MCP), which had the most severe decay incidence. For fungi, in addition to Alternaria being the most abundant in both 1-MCP treatment (59.89%) and control (40.18%), the abundances of Botryosphaeria (16.75%), Penicillium (8.81%), and Fusarium (6.47%) increased significantly with the extension of storage time. They became the primary pathogens to cause fruit decay in control, but they were markedly decreased in 1-MCP treatment, resulting in reduced disease incidence. For bacteria, the abundance of Gluconobacter (50.89%) increased dramatically at day 15 in the control fruit, showing that it also played a crucial role in fruit decay. In addition, Botryosphaeria, Fusarium fungi, and Massilia, Kineococcus bacteria were identified as biomarkers to distinguish 1-MCP treatment and control using Random Forest analysis. The redundancy analysis (RDA) result showed that the amount of Botryosphaeria, Penicillium, and Fusarium were positively correlated with disease incidence and respiration rate of pear fruits while negatively correlated with fruit firmness. This investigation is the first comprehensive analysis of the microbiome response to 1-MCP treatment in post-harvest pear fruit, and reveals the relationship between fruit decay and microbial composition in pear fruit.

Beta-Cyclodextrin: Eugenol Inclusion Complexes: Characterization and Antifungal Capacity

Eugenol (EUG) is the principal component of clove essential oil. It has demonstrated excellent antifungal properties against B. cinerea, one of the most important fungus in the fresh fruit decay. However, this substance is highly volatile, thermolabile and the direct contact with a food induce undesirable changes in the organoleptic properties. For this reason, the application of EUG represents a big challenger and its encapsulation through inclusion complexes formation with β-cyclodextrin (β-CD) is presented as a solution. In this way, the aim of this work was to develop, characterize and assess the antifungal capacity of inclusion complexes β-CD:EUG. For this, co-precipitation was used as method of inclusion complexes synthesis. The quantity of entrapped EUG was determined by gaseous chromatography. The inclusion complexes were characterized by thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR). Moreover, the antifungal activity was probed in a headspace system. Results showed that the EUG entrapped quantity was of 68,5 mg/g inclusion complexes. Furthermore, the characteristic peaks of EUG did not appear in inclusion complexes TGA thermogram and FTIR spectrum which confirm the effective compound encapsulation. Finally, inclusion complexes inhibited the growing of A. cinerea at 53% and avoided the fungal sporulation. These findings suggest that the β- CD:EUG inclusion complexes are suitable to use in the storage and transportation of fresh fruits to prevent their deterioration. Keywords: Botrytis cinerea, fresh fruits, headspace. Resumen El eugenol (EUG) es el principal componente del aceite esencial de clavo de olor. Éste ha destacado por su efectivo control de Botrytis cinerea, uno de los hongos más importantes que provoca la pudrición de frutas frescas. Sin embargo, esta sustancia es altamente volátil, termolábil y provoca cambios desagradables en las propiedades organolépticas del alimento si está en contacto directo con el mismo, por lo que su aplicación presenta un gran desafío. Ante esto, se propone su encapsulación a través de la formación de complejos de inclusión con β-ciclodextrina (β-CD). En este sentido, el objetivo de la presente investigación fue desarrollar, caracterizar y evaluar la capacidad antifúngica de complejos de inclusión β-CD:EUG. Éstos se sintetizaron mediante el método de co-precipitación, y la cantidad de EUG atrapada en la β-CD fue cuantificada por cromatografía de gases. Los complejos de inclusión se caracterizaron a través de análisis termogravimétrico (TGA) y espectroscospía infrarroja con transformada de Fourier (FTIR). Además, su actividad antifúngica se evaluó en un sistema de espacio de cabeza. Los resultados mostraron que la cantidad de EUG atrapada fue de 68,5 mg/g de complejo de inclusión. Además, en su termograma TGA y espectro FTIR no se observaron los picos característicos del EUG, confirmando la efectiva encapsulación del compuesto. Finalmente, los complejos de inclusión inhibieron el 53% del crecimiento de B. cinerea y evitaron su esporulación. Estos resultados permiten sugerir el uso de complejos de inclusión β-CD:EUG en el almacenamiento y transporte de frutas frescas para prevenir su deterioro. Palabras clave: Botrytis cinerea, frutas frescas, espacio de cabeza.