Biological effect of irradiated chitosan on plants in vitro

Abstract

For degradation of chitosan, chitosan with an 80% degree of deacetylation and a weight-average molecular mass (Mw) of approx. 48 kDa was irradiated with gamma-rays at doses up to 200 kGy in a 10% (w/v) solution. The Mw of chitosan was reduced from 48 to 9.1 kDa by irradiation. The characteristics of irradiated chitosan were analysed by using Fourier-transform IR spectroscopy and an elemental analyser. The amino group was found to be stable, whereas the C-O-C group decreased with increase in the dose. The product of chitosan irradiated at 100 kGy with an Mw of approx. 16 kDa showed the strongest growth promotion effect on plants in vitro. For shoot culture, supplementation with irradiated chitosan increased the fresh biomass of shoot clusters (7.2-17.0%) as well as the shoot multiplication rate (17.9-69.0%) for Chrysanthemum morifolium (florist's chrysanthemum), Limonium latifolium (limonium or sea-lavender), Eustoma grandiflorum (lisianthus, tulip gentian or Texas bluebell) and Fragaria ananassa (modern garden strawberry). The optimum concentrations of irradiated chitosan were found to be approx. 70-100 mg/l for chrysanthemum, 50-100 mg/l for lisianthus and 30-100 mg/l for limonium. For the plantlet culture, the optimum concentrations were found to be approx. 100 mg/l for chrysanthemum, 30 mg/l for lisianthus, 40 mg/l for limonium and 50 mg/l for strawberry. Supplementation with optimum concentrations of irradiated chitosan resulted in a significant increase in the fresh biomass (68.1% for chrysanthemum, 48.5% for lisianthus, 53.6% for limonium and 26.4% for strawberry), shoot height (19.4% for chrysanthemum, 16.5% for lisianthus, 33.9% for limonium and 25.9% for strawberry) and root length (40.6% for chrysanthemum, 66.9% for lisianthus, 23.4% for limonium and 22.6% for strawberry). In addition, treatment with irradiated chitosan enhanced the activity of chitosanase in treated plants and also improved the survival ratio and growth of the transferred plantlets acclimatized for 10-30 days under greenhouse conditions.

Effects of Chitooligosaccharide Coating Combined with Selected Ionic Polymers on the Stimulation of Ornithogalum saundersiae Growth

“…It is used in plant production as a growth biostimulator [ 6 ] and elicitor of pathogen resistance [ 7 , 8 ]. The biological activity of chitosan depends on diverse factors as its morphological structure, degree of deacetylation and molecular weight [ 9 , 10 ]. Chitooligosaccharides (COS) are high molecular weight homo- or heterooligomers obtained from chitin or chitosan [ 11 ].…”

Effects of pre-harvest chitosan application on growth parameters and total phenolic - antioxidant contents of bitter gourd (Momordica charantia L.)

“…It has been reported that chitosan accelerated and prompted the plant's growth and morphological characteristics of various plants such as gerbera 6 (Wanichpongpan et al, 2000), soybean sprouts , and sweet basil . Luan et al (2005) demonstrated the stimulating effect of chitosan on shoot lengths and fresh biomass in several plants such as Chrysanthemum morifolium, Limonium latifolium, Eustoma grandiflora, and Fragaria ananasa. The research conducted by Salachna and Zawadzińska (2014) has shown that chitosan can be used as a biostimulator on freesia plants.…”

Radiation Degradation of β-Glucan with a Potential for Reduction of Lipids and Glucose in the Blood of Mice

“…Gamma irradiation has been proposed as a useful method for the degradation of natural polysaccharides (cellulose, alginate, chitosan, etc.) via the cleaving of glycosidic bonds of polymer molecules [32,33,34]. The main advantages of radiation degradation for natural polysaccharides include the ability to forego chemicals or special conditions, ease of process control and large-scale application, a simple process, high degradation yield, high purity product, and low cost [32].…”