RefDoc
Haut

Faire une nouvelle recherche
Make a new search
Lancer la recherche


Titre du document / Document title

Nutritional effects on oxalic acid production and solubilization of gypsum by Aspergillus niger

Auteur(s) / Author(s)

GHARIEB M. M. (1) ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

(1) Department of Botany, Faculty of Science, Menoufia University, Shebein El-Koom, EGYPTE

Résumé / Abstract

The effects of varying carbon, nitrogen, phosphate and sulphate source on solubilization of natural gypsum by Aspergillus niger were assessed. The fungus was grown on Czapek Dox agar amended with 0.5% (w/v) gypsum. Solubilization activity was monitored by measuring the clear zone formed underneath and around the growing colonies. On different concentrations of glucose, nitrate, ammonium, urea, phosphate and sulphate, linear growth rate [Rg] was not significantly correlated with gypsum solubilization rate [Rs] but the solubilization ratio [Rs/Rg] was increased by increasing the concentration of glucose, nitrate, and urea. On ammonium nitrogen, the mycelial dry weight was negatively correlated with linear growth, and gypsum solubilization activity was markedly lower than that on nitrate or urea. Gypsum solubilization was strongly correlated with both biomass dry weight and oxalic acid production. The fungus was unable to grow on carbonate, as a carbon source, but the addition of sucrose alleviated the effect of alkalinity caused by sodium carbonate. The optimum C:N ratio for gypsum solubilization was 50:1, and the importance of phosphate, rather than sulphate, was also shown. Implication of critic acid in the solubilization process was also suggested. This work emphasizes the importance of organic acids, particularly oxalic acid, production by fungi in gypsum solubilization and revealed the optimum nutritional conditions for the solubilization process.

Revue / Journal Title

Mycological research    ISSN  0953-7562 

Source / Source

2000, vol. 104 (5), pp. 550-556 (47 ref.)

Langue / Language

Anglais

Editeur / Publisher

Elsevier, Kidlington, ROYAUME-UNI  (1989-2009) (Revue)

Mots-clés anglais / English Keywords

Nutrition

;

Dose activity relation

;

Production

;

Biosynthesis

;

Solubilization

;

Sulfates

;

Aspergillus niger

;

Gypsum

;

Oxalic acid

;

Carbon

;

Nitrogen

;

Phosphorus

;

Fungi Imperfecti

;

Fungi

;

Thallophyta

;

Nutrient

;

Mots-clés français / French Keywords

Nutrition

;

Relation dose réponse

;

Production

;

Biosynthèse

;

Solubilisation

;

Sulfate

;

Aspergillus niger

;

Gypse

;

Oxalique acide

;

Carbone

;

Azote

;

Phosphore

;

Fungi Imperfecti

;

Fungi

;

Thallophyta

;

Nutriment

;

Mots-clés espagnols / Spanish Keywords

Nutrición

;

Relación dosis respuesta

;

Producción

;

Biosíntesis

;

Solubilización

;

Sulfato

;

Aspergillus niger

;

Yeso

;

Oxálico ácido

;

Carbono

;

Nitrógeno

;

Fósforo

;

Fungi Imperfecti

;

Fungi

;

Thallophyta

;

Nutriente

;

Localisation / Location

INIST-CNRS, Cote INIST : 3185, 35400009175671.0070

Nº notice refdoc (ud4) : 1480073



Faire une nouvelle recherche
Make a new search
Lancer la recherche
Bas