title: The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration.
abstract: This study aimed to investigate the role of ascorbate peroxidase (APX), guaiacol peroxidase (GPX), polysaccharides, and protein contents associated with the early events of postharvest physiological deterioration (PPD) in cassava roots. Increases in APX and GPX activity, as well as total protein contents occurred from 3 to 5 days of storage and were correlated with the delay of PPD. Cassava samples stained with Periodic Acid-Schiff (PAS) highlighted the presence of starch and cellulose. Degradation of starch granules during PPD was also detected. Slight metachromatic reaction with toluidine blue is indicative of increasing of acidic polysaccharides and may play an important role in PPD delay. Principal component analysis (PCA) classified samples according to their levels of enzymatic activity based on the decision tree model which showed GPX and total protein amounts to be correlated with PPD. The Oriental (ORI) cultivar was more susceptible to PPD.
authors.affiliation: Federal University of Santa Catarina, Plant Science Center, Plant Morphogenesis and Biochemistry Laboratory, 1346 Admar Gonzaga Road, Florianópolis, SC 88.034-001, Brazil. Electronic address: uaceleste@yahoo.com.br.
authors.forename: Virgílio Gavicho
authors.initials: VG
authors.lastname: Uarrota
authors.affiliation: Federal University of Santa Catarina, Plant Science Center, Plant Morphogenesis and Biochemistry Laboratory, 1346 Admar Gonzaga Road, Florianópolis, SC 88.034-001, Brazil.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Moresco
authors.affiliation: Federal University of Santa Catarina, Laboratory of Plant Cell Biology, Centre for Biological Sciences, Department of Cell Biology, Embryology and Genetics, Florianópolis, SC 88040-900, Brazil.
authors.forename: Eder Carlos
authors.initials: EC
authors.lastname: Schmidt
authors.affiliation: Federal University of Santa Catarina, Laboratory of Plant Cell Biology, Centre for Biological Sciences, Department of Cell Biology, Embryology and Genetics, Florianópolis, SC 88040-900, Brazil.
authors.forename: Zenilda Laurita
authors.initials: ZL
authors.lastname: Bouzon
authors.affiliation: Santa Catarina State Agricultural Research and Rural Extension Agency (EPAGRI), Experimental Station of Urussanga (EEUR), SC 446 Road, Km 19, Urussanga, SC 88840-000, Brazil.
authors.forename: Eduardo da Costa
authors.initials: Eda C
authors.lastname: Nunes
authors.affiliation: Santa Catarina State Agricultural Research and Rural Extension Agency (EPAGRI), Experimental Station of Urussanga (EEUR), SC 446 Road, Km 19, Urussanga, SC 88840-000, Brazil.
authors.forename: Enilto de Oliveira
authors.initials: Ede O
authors.lastname: Neubert
authors.affiliation: Santa Catarina State Agricultural Research and Rural Extension Agency (EPAGRI), Experimental Station of Urussanga (EEUR), SC 446 Road, Km 19, Urussanga, SC 88840-000, Brazil.
authors.forename: Luiz Augusto Martins
authors.initials: LA
authors.lastname: Peruch
authors.affiliation: Centre of Biological Engineering (CEB), University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: Rocha
authors.affiliation: Federal University of Santa Catarina, Plant Science Center, Plant Morphogenesis and Biochemistry Laboratory, 1346 Admar Gonzaga Road, Florianópolis, SC 88.034-001, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Maraschin
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D060387:Ascorbate Peroxidases / Q000032:analysis*; D005519:Food Preservation; D061353:Food Storage; D002365:Manihot / Q000737:chemistry* / Q000201:enzymology / Q000502:physiology*; D009195:Peroxidase / Q000032:analysis*; D010829:Physiological Phenomena; D018517:Plant Roots / Q000737:chemistry / Q000201:enzymology; D025341:Principal Component Analysis; D013213:Starch / Q000032:analysis*
chemical_list: D000975:Antioxidants; D013213:Starch; C121048:guaiacol peroxidase; D060387:Ascorbate Peroxidases; D009195:Peroxidase
keywords: Alpha tocopherol (PubChem CID: 14985); Antioxidant enzymes; Cassava roots; Cellulose (PubChem CID: 3084047); Guaiacol (PubChem CID: 460); L-ascorbate (PubChem CID: 54670067); L-ascorbic acid peroxidase; Polysaccharides; Postharvest; Starch (PubChem CID: 439341)