Development of callus colonies from the isolated microspore culture of capsicum annuum l.

Androgenesis in Capsicum annuum L. via isolated microspore culture, with a limited scope, was studied. Donor genotype, i.e. U-130, was a doubled haploid. Intact flower buds containing microspores from early to late uninucleate stages were pretreated with a mannitol starvation medium both at 10 and 35°C for 7 days. High temperature treatment tested here, although considered effective in Capsicum anther culture, was detrimental and therefore flower buds from this treatment were not used. Following pretreatment at 10°C microspores were isolated and cultured on NLN medium (20) without growth regulators. Osmoticum and carbon was supplied to the microspores with 100, 130, and 170 g/1 sucrose. Only 170 g/1 culture was maintained and the rest of the cultures were lost to contamination. Callus colonies were obtained on the 30th and 60th days at rate of 40.5 and 67%, respectively. Callus colonies were subcultured to MS media containing 2, 4-D at 1 and 2 mg/1, but further development was not obtained. It was concluded that the approach adopted earlier on the cellular and molecular characterization studies of induced multinucleate Capsicum microspores (12, 14, 15) may lead to high frequency regeneration of haploids via callus colonies, as obtained in the present study, hence, isolated microspore culture using mannitol starvation as pretreatment has potentiality in Capsicum annum L. breeding. © 2003 Taylor and Francis Group, LLC

Polysaccharidase and glycosidase production of avicel grown rumen fungus Orpinomyces sp. GMLF5

Extracellular and cell-associated enzyme preparations were obtained from ruminal anaerobic fungi Orpinomyces sp. GMLF5 grown in culture containing microcrystalline cellulose (avicel) as sole energy source and degradation capacities of the preparations towards several polysaccharides and glycosides were studied. Fungus showed substantial increases in xylanase, carboxymethyl cellulase (CMCase), lichenase, amylase, β-xylosidase, β-glucosidase and α-L-arabinofuranosidase activities between 72 and 168 hours. High amounts of cell associated β-xylosidase were noted in 4 and 5 days old cultures. Optimum temperature and pH of the polysaccharidases were found at 50 °C and 6.0–6.5, respectively. Xylanase was found to be virtually stable at 50°C, CMCase and lichenase were stable at 40 °C for 200 min, however amylase was found more sensitive to heat treatment. The fibrolytic enzymes of the isolate GMLF5 were observed to be capable of hydrolyze the avicel

Cloning, characterization and paper pulp applications of a newly isolated DyP type peroxidase from Rhodococcus sp. T1

WOS: 000462022300057PubMed: 30474775A newly identified ligninolytic Rhodococcus strain (Rhodococcus sp. T1) was isolated from forestry wastes (Trabzon/Turkey). The DyP type peroxidase of Rhodococcus sp. T1 (DyPT1) was cloned, characterized and paper treated for industrial applications. Molecular weight of the protein was about 38kDa. The kinetic parameters were 0.94mM and 1417.53 mu mol/min/mg for Km and Vmax, respectively. The enzyme was active at the temperature range of 25-65 degrees C and optimum temperature was 35 degrees C, enzyme was stable up to 6 days at room temperature. Optimum pH of the DyPT1 was 4.0 and it was stable between pH 4.0-6.0 up to 8 days at room temperature. Effects of some metal ions, Hemin, and some chemical agents on DyPT1 were determined. Hemin has implemented protective effects on the stability and the activity of the enzyme in long time periods when added into growing medium. DyPT1 was applied to eucalyptus kraft pulp for analyzing the bleaching efficiency, physical and optical tests of the manufuctared paper were carried out. Application of lignin peroxidase to kraft pulp caused a decrease of 5.2 units for kappa number and an increase from 52.05 to 64.18% in the delignification rate.Karadeniz Technical University Research Foundation [FBA-2015-5182]This study was financially supported by Karadeniz Technical University Research Foundation (Project No: FBA-2015-5182)