Production of pectolytic enzymes by Aspergillus niger: effect of inoculum size and potassium hexacyanoferrate II-trihydrate

1990 ◽  
Vol 33 (4) ◽  
Author(s):  
Jo?ica Friedrich ◽  
Aleksa Cimerman ◽  
Walter Steiner
2013 ◽  
Vol 48 (1) ◽  
pp. 25-32 ◽  
Author(s):  
S Islam ◽  
B Feroza ◽  
AKMR Alam ◽  
S Begum

Pectinase activity among twelve different fungal strains, Aspergillus niger IM09 was identified as a potential one to produce maximal level 831 U/g at pH 4.0. Media composition, incubation temperature, incubation time, substrate concentration, aeration, inoculum size, assay temperature and nitrogen sources were found to effect pectinase activity. Moisture content did not affect the activity significantly. Media composition was varied to optimize the enzyme production in solid state fermentation. It was observed that the highest pectinase activity of 831.0 U/g was found to produce in presence of yeast extract as a nitrogen source in combination with ammonium sulfate in assay media. Aeration showed positive significant effects on pectinase production 755 U/g at 1000 ml flasks. The highest pectinase production was found at 2 g pectin (521 U/g) used as a substrate. Pectinolytic activity was found to have undergone catabolite repression with higher pectin concentration (205 U/g at 5 g pectin). The incubation period to achieve maximum pectinase activity by the isolated strain Aspergillus niger IM09 was 3 days, which is suitable from the commercial point of view. DOI: http://dx.doi.org/10.3329/bjsir.v48i1.15410 Bangladesh J. Sci. Ind. Res. 48(1), 25-32, 2013


2011 ◽  
Vol 5 (3) ◽  
pp. 14-21
Author(s):  
Muhamed Omar Abdulatif ◽  
Hyder H. Assmaeel ◽  
Raghad kadhim Obeid ◽  
Ayat Adnan Abbas

he Xylanase producing strain Aspergillus niger was isolated from soil on potato dextrose agar in the presence of xylan as its first substrate for primary isolation, and then grown under liquid medium fermentation in the presence of crude xylan (rice husk) to produce D-Xylanase. the optimum conditions were determined as follows: the Optimum pH for xylanase production was found pH 5.0, xylanase was induced by xylan (rice husk) 0.1% and the production was (61.221 U/ml) and nitrogen source Yeast extract recorded highest enzyme production( 89.71 U/ml), and repressed by carbon source xylose the highest enzyme production (88.69 U/ml). The optimum temperature was 40°с for xylanase production was (35.15 U/ml), the optimum period after 7 days of incubation was (52.33 U/ml) ,the optimum substrate concentration 0.1% was (45.95 U/ml), and the optimum inoculum size was 1 x 106 (spore /ml) recorded (57.19 U/ml ).


2004 ◽  
Vol 70 (6) ◽  
pp. 3506-3511 ◽  
Author(s):  
Andrew Plumridge ◽  
Stephan J. A. Hesse ◽  
Adrian J. Watson ◽  
Kenneth C. Lowe ◽  
Malcolm Stratford ◽  
...  

ABSTRACT The growth of the filamentous fungus Aspergillus niger, a common food spoilage organism, is inhibited by the weak acid preservative sorbic acid (trans-trans-2,4-hexadienoic acid). Conidia inoculated at 105/ml of medium showed a sorbic acid MIC of 4.5 mM at pH 4.0, whereas the MIC for the amount of mycelia at 24 h developed from the same spore inoculum was threefold lower. The MIC for conidia and, to a lesser extent, mycelia was shown to be dependent on the inoculum size. A. niger is capable of degrading sorbic acid, and this ability has consequences for food preservation strategies. The mechanism of action of sorbic acid was investigated using 31P nuclear magnetic resonance (NMR) spectroscopy. We show that a rapid decline in cytosolic pH (pHcyt) by more than 1 pH unit and a depression of vacuolar pH (pHvac) in A. niger occurs in the presence of sorbic acid. The pH gradient over the vacuole completely collapsed as a result of the decline in pHcyt. NMR spectra also revealed that sorbic acid (3.0 mM at pH 4.0) caused intracellular ATP pools and levels of sugar-phosphomonoesters and -phosphodiesters of A. niger mycelia to decrease dramatically, and they did not recover. The disruption of pH homeostasis by sorbic acid at concentrations below the MIC could account for the delay in spore germination and retardation of the onset of subsequent mycelial growth.


1981 ◽  
Vol 46 (12) ◽  
pp. 3145-3156 ◽  
Author(s):  
Kvetoslava Heinrichová ◽  
Mária Dzúrová

A mixture of pectolytic enzymes was isolated from a commercial preparation of Pectinex Ultra. endo-D-Galacturonanase (EC 3.2.1.15) was obtained from this mixture of enzymes, produced by Aspergillus niger cultures, by affinity chromatography using cross-linked pectic acid as a support and by subsequent chromatography on a Sephadex G-100 column. One form of endo-D-galacturonanase only of approximate molecular weight of 35 000 was detected in the purified product by electrophoresis in polyacrylamide gel. The enzyme showed maximal activity and stability at pH 4.9 and 40°. The mode of degradation of a high molecular weight substrate and the per cent of the glycosidic bonds cleaved (6%) at a viscosity decrease by 50% indicate an endo type action pattern. endo-D-Galacturonanase was characterized by the mode of cleavage and the kinetic constants Km and V for oligogalacturonic acids and polygalacturonic acid. On the basis of the knowledge of the kinetic constants and the degradation products the mode of action of the enzyme and the extent of its active site are discussed.


2018 ◽  
Vol 10 (1) ◽  
pp. 60-67 ◽  
Author(s):  
Patricia F. OMOJASOLA ◽  
Damola O. ADEJORO

The present study aimed to produce gibberellic acid through fermentation using banana (Musa sapientum) peel waste as substrate. Banana peel, a domestic and industrial waste, constitutes a potential source of cheap fermentable substrate for the production of other value-added products. Fusarium moniliforme ATCC 10052 and Aspergillus niger CBS 513.88 were used as fermenting organisms. The substrate was dried, ground and its proximate composition determined. The powdered substrate was added to a modified CzapekDox broth (a semisynthetic medium), with Carboxyl methylcellulose (CMC) as control. The fermentation conditions were: pH 5.5; inoculum size 1% (5 × 105 spores/mL F. moniliforme) (2 × 106 spores/mL A. niger); substrate concentration 2 g; temperature 25 ± 2 oC; fermentation time 7 days. The fermentation was optimized by varying pH, inoculum size, substrate concentration and fermentation time. The extracted GA was subjected to infra-red spectroscopy using FT-IR. The parameters which gave the highest GA yields were thereafter combined in a single fermentation. The results of proximate analysis of banana peel substrate revealed 8.65% moisture, 9.54% protein, 5.40% lipids, 11.45% ash, 22.34% crude fibre, and 42.62% carbohydrate. The GA yields of 13.55 g/L and 12.44 g/L were produced from the banana peel substrate and 3.62 and 2.61 g/L from the CMC control by F. moniliforme and A. niger respectively. Under optimized conditions, F. moniliforme produced 17.48 g/L GA, while A. niger produced 13.50 g/L. Extracted GA was similar to standard GA sample and the present results support the potential use of banana peel for fermentative GA production.


Author(s):  
Abdulhakeem Olarewaju Sulyman ◽  
Yusuf A Iyanda ◽  
Afolabi Olaniyi Opasola ◽  
OtunOla Adedayo ◽  
Raliat Abimbola Aladodo

This research investigated the purification and partial characterization of cellulase produced by Aspergillus niger cultured on Vitellaria paradoxa shells. Cellulase (endoglucanase) from A. niger was produced under optimum fermentation conditions at 35 °C, pH 4.7, V. paradoxa, 4 g/L, inoculum size of 10 mm and the fermentation media incubated for 120 hours. The crude endoglucanase obtained were partially purified by subjecting to ammonium sulphate precipitation, dialysis and gel filtration chromatography for further purification. The effect of temperature and pH on the activity of purified endoglucanase was determined. Cellulase was purified to 734.33 folds by Sephadex G-100 column chromatography with a specific activity and yield of 4.406 U/mg and 63.03% respectively. Fractions 4 and 7 contained the highest endoglucanase activity out of 18 fractions collected and the two fractions were pooled for further analysis. The activity of purified endoglucanase was optimum at a temperature of 40 °C and pH 5. Therefore, the purified endoglucanase produced may be explored in detergent industry.


2019 ◽  
Vol 81 (6) ◽  
Author(s):  
Halifah Pagarra ◽  
Roshanida A. Rahman ◽  
Rachmawaty ◽  
Nor Hasmaliana Abdul Manas

Exo-polygalacturonase was produced by Aspergillus niger ATCC 120120 in a solid-state fermentation using Nephrolepis biserrata leaves. Factors affecting the production of exo-polygalacturonase were determined using a two-level fractional factorial design. The screening process for six factors; pH, incubation time, temperature, pectin concentration, inoculum size and moisture content, that influence the production of exo-polygalacturonase by A. niger was performed. The result of variance analysis (ANOVA) suggested that there were four statistically significant (P < 0.005) factors in the production of exo-polygalacturonase by A. niger. These factors were incubation time, temperature, pectin concentration and moisture content. The statistical analysis shows that the linear mathematical model is significant with coefficient of determination (R2) value of 0.9711. The optimum production of exo-polygalacturonase obtained using the model in this study was at 40.00 U/g.


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