title: Photodegradation of ethylene by use of TiO2sol-gel on polypropylene and on glass for application in the postharvest of papaya fruit.
abstract: The papaya is a commercially important fruit commodity worldwide. Being a climacteric fruit, it is highly perishable. Thus, for the transportation of papaya fruit for long distances without loss of quality, it is necessary to avoid the autocatalytic effect of ethylene in accelerating the ripening of the fruit. This work addresses the application of heterogeneous photocatalysis to the degradation of ethylene. A TiO2sol-gel supported on polypropylene (PP) and on glass was used as the catalytic material, and a UV-A lamp was employed as the radiation source. Initially, a concentration of 500 ppbv ethylene was exposed to the catalyst material irradiated by UV-A radiation. A sensitive photoacoustic spectrometer was used to monitor the photocatalytic activity. The TiO2sol-gel supported on the glass substrate was more efficient than on the PP in degrading the ethylene. Under direct UV-A exposure, the skin appearance of 'Golden' papaya was damaged, depreciating the fruit quality and thus preventing its commercialization. However, the feasibility of the heterogeneous photocatalysis to preserve the fruit quality was achieved when ethylene was removed from the storage ambient using fans, and then, this plant hormone was degraded by a reactor set apart in a ventilation closed system.
authors.affiliation: Grupo de Pesquisa em Química Ambiental, Lab. de Ciências Químicas, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ, 28013-602, Brazil.
authors.forename: Ruth Evelyn R S
authors.initials: RERS
authors.lastname: Lourenço
authors.affiliation: Lab. de Ciências Físicas, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ, 28013-602, Brazil.
authors.forename: Amanda A N
authors.initials: AAN
authors.lastname: Linhares
authors.affiliation: Lab. de Melhoramento Genético Vegetal, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ, 28013-602, Brazil.
authors.forename: André Vicente
authors.initials: AV
authors.lastname: de Oliveira
authors.affiliation: Lab. de Ciências Físicas, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ, 28013-602, Brazil.
authors.forename: Marcelo Gomes
authors.initials: MG
authors.lastname: da Silva
authors.affiliation: Lab. de Melhoramento Genético Vegetal, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ, 28013-602, Brazil.
authors.forename: Jurandi Gonçalves
authors.initials: JG
authors.lastname: de Oliveira
authors.affiliation: Grupo de Pesquisa em Química Ambiental, Lab. de Ciências Químicas, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Avenida Alberto Lamego 2000, Campos dos Goytacazes, RJ, 28013-602, Brazil. mccanela@uenf.br.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Canela
mesh_terms: D029441:Carica / Q000737:chemistry*; D005030:Ethylenes / Q000737:chemistry*; D005898:Glass / Q000737:chemistry*; D010782:Photolysis; D010937:Plant Growth Regulators / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D005030:Ethylenes; D010937:Plant Growth Regulators; D011126:Polypropylenes; C009495:titanium dioxide; C036216:ethylene; D014025:Titanium
keywords: Carica papaya L.; Fruit storage; Photocatalysis; Skin colour; UV-A radiation