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Hidayat A.,Ehime University | Hidayat A.,Forest Research and Development Agency FORDA | Tachibana S.,Ehime University | Itoh K.,Ehime University
Fungal Biology | Year: 2012

Sixty-two rotted wood and soil samples were used to screen for chrysene-degrading fungi. A strain of Fusarium, named F092, was identified as most capable of degrading chrysene. F092 was active under saline and nonsaline conditions, breaking down 48 % of the chrysene in 30 d. The percentage of chrysene degraded did not change at 35‰ salinity with pH 8.2 in solid and liquid cultures. The degradation under saline conditions increased about 0.6- and 2.1-fold in cultures with polypeptone and Tween80, and 0.03-fold in agitated cultures. F092 secreted nonligninolytic enzymes named 1,2-dioxygenase and 2,3-dioxygenase. The level of 1,2-dioxygenase activity reached 203.5 U L -1 at 30 d and that of 2,3-dioxygenase activity, 29.7 U L -1 at 40 d. The degradation pathway was clarified from the intermediates produced; chrysene 1,2-oxide, chrysene trans-1,2-dihydrodiol, 1-hydroxy 2-naphtoic acid, and catechol. F092 is a potential degrader of chrysene for bioremediation. © 2012 The British Mycological Society.

Hidayat A.,Ehime University | Hidayat A.,Forest Research and Development Agency FORDA | Tachibana S.,Ehime University
International Biodeterioration and Biodegradation | Year: 2013

Degradation of 2,4,8-trichlorodibenzofuran (2,4,8-TCDF) by the isolate F0607, identified as belonging to the genus Cerrena, was investigated in liquid culture medium. Strain F0607 showed good decolorization and production of ligninolytic enzymes. The degradation of 2,4,8-TCDF per-unit biomass increased during the incubation period in presence of 1 or 10 mg l-1 2,4,8-TCDF and the mycelial biomass increased with the increase in 2,4,8-TCDF concentration. The rate of glucose consumption (k1) also increased rapidly when 2,4,8-TCDF was present in the culture. All three types of ligninolytic enzymes were detected in which laccase had the highest enzyme activity. CuSO4 could induce the activity of laccase and increase the degradation of 2,4,8-TDCF, whereas 1-hydroxybenzotriazole (HBT) also enhanced degradation via nitroxy radical (>N-O) oxidation. © 2012 Elsevier Ltd.

Hidayat A.,Ehime University | Hidayat A.,Forest Research and Development Agency FORDA | Tachibana S.,Ehime University
Journal of Environmental Science and Technology | Year: 2013

Biodegradation of crude oil-A and-C and n-octadecane, by the Fusarium sp. F092 was investigated under saline conditions. In liquid saline culture, less crude oil-C (56%) than crude oil-A (89%) was degrade which was increased by the addition of optimum surfactant T80 (78%) or T40 (67%), or Mn2+ (67%). In sea sand contaminated with crude oil-C, the degradation was higher than in soil which indicated that F092 was suitable to degrade oil under saline conditions. The metabolites of the aliphatic fraction with n-octadecane were identified to form six carboxylic acid groups, where the dioxygenase and monooxygenase inhibitor influenced the degradation of n-octadecane. This suggested that F092 could initially convert n-octadecane to form octadecyl peroxides by a dioxygenase and was further catalyzed to produce carboxylic acid. F092 is a potential degrader for bioremediation in crude oil-contaminated saline environments. © 2013 Asian Network for Scientific Information.

Prihantini A.I.,Ehime University | Prihantini A.I.,Forest Research and Development Agency FORDA | Tachibana S.,Ehime University | Itoh K.,Ehime University
Pakistan Journal of Biological Sciences | Year: 2014

The antioxidant and α-glucosidase inhibitory activities of the methanolic leaf extracts of some subtropical plants were evaluated in the present study. Antioxidant activity was evaluated based on 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, reducing power, hydrogen peroxide and β-carotene bleaching assays. α-Glucosidase inhibitory activity and enzyme kinetics as well as the total phenolic content of the extracts were also investigated. Elaeocarpus sylvestris extract had the highest activities on all the antioxidant assays performed such as DPPH scavenging activity (IC50 12.7±0.5 μg mL-1), reducing power (491.1±6.3 mg QE g -1 dry extract), hydrogen peroxide (IC50 65.6±0.4 μg mL-1) and β-carotene bleaching assays (IC50 5.1±1.9 μg mL-1). The total phenolic content of the E. sylvestris extract also had the highest values for gallic acid, quercetin and rutin equivalents (353.8±28.6 mg GAE g-1 dry extract; 294.9±24.5 mg QE g-1 dry extract; 663.0±52.3 mg RE g-1 dry extract, respectively). α-Glucosidase inhibition assay revealed that Distylium racemosum had the highest activity with an IC50 value of 22.6±1.9 μg mL-1. The results of the present study revealed the potencies of E. sylvestris, D. racemosum, Acer mono Maxim and Liquidambar styraciflua as alternative sources for antioxidants and α-glucosidase inhibitors. © 2014 Asian Network for Scientific Information.

Ordonez J.C.,The World Agroforestry Center | Luedeling E.,International Center for Research in Agroforestry | Kindt R.,International Center for Research in Agroforestry | Tata H.L.,The World Agroforestry Center | And 4 more authors.
Current Opinion in Environmental Sustainability | Year: 2014

On-farm tree diversity patterns result from a social-ecological process shaped by different actors. Farmer preferences, tree-site matching, seed dispersal, tree domestication and delivery via nurseries all play important roles in forming these patterns. As part of a wider interest in tree cover transition curves that link agroforestation stages of landscapes to a preceding deforestation process, we here focus on 'tree diversity transition curves' i. as a conceptual framework to understand current processes and how shifts in drivers affect tree diversity and ii. to help identify constraints and opportunities for interventions. We provide some examples of current research efforts and make suggestions for databases and analyzes that are required to improve our understanding of tree diversity transitions. We explore drivers, consequences and entry points for tree diversity management to achieve multifunctional agriculture. © 2013 The Authors.

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