Evaluation of antifungal activity of chitosan in Alternaria alternata and in the quality of “tommy atkins” mango during storage

Alternaria alternata (Black Rot, Black Spot)

“…Several works described the morphological changes induced by chitosan on fungal hyphae and reproductive structures. Similar results were reported by López et al, (2013), who found an intense and broad vacuolization throughout mycelia and conidia, cytoplasmic content leakage and presence of fibrillar material in A. alternata strains with chitosan of low molecular weight applied at a concentration of 1.0% The chitosan-treated mycelium showed predominantly loosened cell walls and, in some areas, lysis was observed.…”

“…Similarly, Reddy et al (2000) reported that stem scar application of chitosan inhibited the development of A. alternata on tomatoes stored at 20°C for 28 days by 34%, and reduces production of pathogenic factors by the fungus, such as cell wall-degrading enzymes (polygalacturonase, pectate lyase, and cellulose), organic acids, and host-specific toxins responsible for fungal penetration and host tissue damage. In a similar study, López et al (2013) found that the use of chitosan of low molecular weight at a concentration of 1.0% reduced mycelial growth and sporulation of A. alternata up to 70% and completely inhibited conidial germination under in vitro conditions. In another study, it was reported that chitosan with medium molecular weight at 2.5% (w/v), incorporated in potato dextrose agar inhibited mycelial growth of A. alternata up to 50.6%, under in vitro conditions (Sánchez-Domínguez et al, 2007).…”

Quality and biochemical changes of ‘Hindi-Besennara’ mangoes during shelf life as affected by chitosan, gallic acid and chitosan gallate

“…The postharvest losses of fresh horticultural commodities such as mangoes may be estimated as high as 50% due to several physiological and pathological disorders (Sivakumar et al 2011;López-Mora et al 2013). Mango is a climacteric fruit with high perishability nature due to rapid ripening, softening and microbial decay (Sivakumar et al 2011).…”

“…Also dipping 'Nam Dok Mai' mangoes, previously inoculated with C. gloeosporioides, in chitosan (from 0.5 to 2.0%) delayed ripening and reduced respiration rate, ethylene production, and weight loss, ascorbic acid, and acidity and reduced diseases progression (Jitareerat et al 2007). However, 'Tommy Atkins' mangoes dipped in 1% chitosan had no effects on fruit ripening, weight loss and black spot incidence, but inhibited the extension of this disease during storage at 12 and 25°C (López-Mora et al 2013). In addition to its function as a protective barrier, chitosan coating can work as carrier for bioactive antioxidants and antimicrobials compounds, such as GA (Yen et al 2002;Chanwitheesuk et al 2007;Sun et al 2014).…”

Microencapsulation of potassium phosphate in chitosan and the effect of spray drying operating variables on the particle size

“…For example, Harris et al encapsulated tramadol in chitosan for controlled release to know the abilities of chitosan as an encapsulating medium [9]. Also, Lopez-Mora et al evaluated the antifungal activity of the chitosan in Alternaria alternata development in relation to mycelial growth, germination and sporulation of Mango during storage [10]. Lastly, Tokárová et al, designed chitosan microspheres by spray drying and studied systematically the effects of different factors, including the chitosan cross-linking ratio (using tripolyphosphate as the cross-linking agent), nanoparticle loading in the polymer matrix, and the internal structure of the microspheres on the in vitro release kinetics.…”