Partial Purification of Amylase from the Culture Filtrates of Aspergillus flavus Grown on Cassava Peels

Author(s):  
M O Oyewale

Amylase from a Cassava peel culture of Aspergillus flavus was partially purified by Ammonium Sulphate precipitation as well as dialysis. The dialysed 60% (NH4)2 SO4 precipitated enzyme had an activity of 1.087 mg T.R.S released/ min/mg protein which was two folds of the activity of the crude culture filtrate. Hydrogen ion concentration as well as temperature had profound influence on enzyme activity of the partially purified enzyme while Amylase activity increased progressively as pH was increased from 3 to 7 reaching a maximum of 1.68 mg T.R.S released/min/mg/protein at PH 7.0. A rapid decrease in amylase activity was observed as pH was increased from 7 to 9 while the amylase activity increased with increase in temperature from 300C to 450C and reached a maximum of 1.15 mg T.R.S. released/min/mg/protein at 450C. Subsequent increase in temperature resulted into decrease in activity of the amylase enzyme.

Author(s):  
M O Oyewale

The mycelial dry weight and dinitrosalicylic acid (D.N.S.A.) method was used to determine growth and amylase production by Aspergillus flavus grown on different carbon sources. Growth of the fungus was determined at 24 h intervals over a period of six days by the dry mycelial weight methods, while the amylase activity in the culture filtrates of A. flavus was determined by the D.N.S.A method. A total of 45 samples were prepared to determine growth and amylase activity of Aspergillus flavus grown on different carbon sources. The concentration of the various carbon sources ranges between 0.4 to 2% W/V. Duncan’s multiple range test was used to determine the level of significance of the different carbon sources for effective growth and amylase production by Aspergillus flavus. Aspergillus flavus demonstrated the capability to produce significant growth and amylase activities in the medium containing soluble starch, sorghum and cassava peel as sole carbon source. The amount of mycelial dry weight produced from soluble starch, sorghum and cassava peel is significantly higher than those produced from other carbon sources. The data revealed that there is a correlation between growth and amylase production by Aspergillus flavus. The available data from this study showed that soluble starch is the best carbon source for optimum growth and amylase production by A flavus while sorghum and cassava peel are close substitute for optimum growth and amylase production by Aspergillus flavus. Keywords: Growth, amylase activity and Aspergillus flavus


2014 ◽  
Vol 13 (52) ◽  
pp. 4657-4662 ◽  
Author(s):  
Moronke Adeyanju Muinat ◽  
Ojewunmi Oyesola ◽  
Akande Temitope ◽  
Nkechi Ezima Esther ◽  
Abolanle Akeredolu Abosede ◽  
...  

2020 ◽  
Vol 36 (2) ◽  
pp. 114-126
Author(s):  
E.T. Aisien ◽  
I.H. Igbinosa

Cassava peels are waste generated from cassava processing and are mostly disposed of in Nigeria by dumping indiscriminately in landfills/waste dumps where they remain as huge mounds and constitute nuisance to the environment. This study was carried out using cassava peels as substrate for the production of α – amylase from three fungi (Aspergillus flavus, Aspergillus niger and Penicillium expansum) selected from twelve microbial isolates obtained from biodegrading cassava peels. The fungi were isolated using cassava peel agar medium and the α – amylase was produced by the solid state fermentation process. The α – amylase was assayed by measuring the decrease in staining power of starch with iodine reagent at 620nm and purified by using Sephadex G-100 and Sephadex C-50. The α – amylase was characterized by examining the effect of temperature, stability at 70oC, pH, substrate concentration, metal ions and EDTA. The results show that the purification fold and specific activity were 95.727, 1.053 Units/mg protein; 81.830, 0.982 Units/mg protein and 85.784, 0.686 Units/mg protein for A. flavus, A. niger and P. expansum respectively. The optimum temperature and pH were 45oC and 4.5 respectively. It was observed that the α – amylase still retained some activity after heating at 70oC for 35 min. The α – amylase activity increased with increase in substrate concentration and metal ion concentration (Na+, K+, Mg2+ and Ca2+) but decreased with increase in heavy metal ion concentration (Hg2+ and Pb2+) and EDTA. Key words: Cassava peels, α – amylase, fungi, starch and Sephadex C – 50.


2014 ◽  
Vol 21 (1) ◽  
pp. 16-22 ◽  
Author(s):  
Ilze Barene ◽  
Irena Daberte ◽  
Sanita Siksna

The aim of the study. The objective of this study was to investigate microscopic, physical and chemical properties of bee bread collected in three regions of Latvia in order to compare the quality and to investigate the possibility of producing granules containing bee bread. Material and methods. Microscopic analysis of bee bread samples was performed. Plant herbaria, special literature and internet sources were used for identification of pollen. Thin layer chromatography was used for identification of carotenoids and flavonoids. Granules were prepared by wet granulation method. Lactose, calcium lactate, calcium carbonate, potato starch and purified water were used as excipients. Appearance, loss on drying, pH of aqueous solution and content of carotenes were estimated. Results. Microscopic analysis showed mostly native pollen identified as willow pollen. Beta-carotene identified and 2 carotenoids found by thin layer chromatography. Two zones of flavonoids found on chromatograms at day light and 6 zones at ultra violet light. The comparison of bee bread samples of 3 regions of Latvia showed insignificant differences in appearance and consistency, hydrogen ion concentration 3.93–4.23, loss on drying 7.72–11.07 %; content of carotenes calculated to bcarotene 6.77–9.35 mg%. Stability study of bee bread samples showed greater changes after storage at 40ºC temperature. All compositions of granules showed appropriate appearance and flowability. Quality of granules: loss on drying 5.48–13.5%, content of carotenes calculated to b-carotene 5.77–6.75 mg%. Conclusions. Pollen of willow can be considered as an indicator of the origin of bee bread in Latvia. Bee bread samples of three regions of Latvia have insignificant differences in physical, chemical parameters.


2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Badusha M. ◽  
Santhosh S

The hydro geochemical features of Neyyar River for a period of one year from May 2015 to April 2016 were analyzed. Six sampling sites were fixed considering physiography and present landuse pattern of the river basin. The residents in the drainage basin are primarily responsible for framing a better landuse and thereby maintain a good water and sediment regime. Geospatial pattern of the present landuse of the study area indicated that the sustainability of this river ecosystem is in danger due to unscientific landuse practices, which is reflected in the river quality as well. The parameters such as hydrogen ion concentration, electrical conductivity, chloride, Biological Oxygen Demand, total hardness and sulphate of river water and Organic Carbon of river bed sediments were analyzed in this study. The overall analysis shows that the highland areas are characterized by better quality of water together with low organic carbon, which is mainly due to better landuse and minimal reclamation. The midland and lowland areas are characterized by poor quality of water with high organic carbon, which is due to high anthropogenic activities and maximum pollutants associated with the region together with the alteration in landuse from a traditional eco-friendly pattern to a severely polluted current pattern.


1977 ◽  
Vol 57 (2) ◽  
pp. 197-203 ◽  
Author(s):  
W. A. RICE ◽  
D. C. PENNEY ◽  
M. NYBORG

The effects of soil acidity on nitrogen fixation by alfalfa (Medicago sativa L.) and red clover (Trifolium pratense L.) were investigated in field experiments at 28 locations, and in greenhouse experiments using soils from these locations. The pH of the soils (limed and unlimed) varied from 4.5 to 7.2. Rhizobia populations in the soil, nodulation, and relative forage yields (yield without N/yield with N) were measured in both the field and greenhouse experiments. Rhizobium meliloti numbers, nodulation scores, and relative yields of alfalfa decreased sharply as the pH of the soils decreased below 6.0. For soils with pH 6.0 or greater, there was very little effect of pH on any of the above factors for alfalfa. Soil pH in the range studied had no effect on nodulation scores and relative yields of red clover. However, R. trifolii numbers were reduced when the pH of the soil was less than 4.9. These results demonstrate that hydrogen ion concentration is an important factor limiting alfalfa growth on acid soils of Alberta and northeastern British Columbia, but it is less important for red clover. This supports the continued use of measurements of soil pH, as well as plant-available Al and Mn for predicting crop response to lime.


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