Kinetics, detergent compatibility and feather-degrading capability of alkaline protease from Bacillus subtilis AKAL7 and Exiguobacterium indicum AKAL11 produced with fermentation of organic municipal solid wastes

2020 ◽  
Vol 55 (11) ◽  
pp. 1339-1348
Author(s):  
Tanvir Hossain Emon ◽  
Al Hakim ◽  
Diptha Chakraborthy ◽  
Farhana Rumzum Bhuyan ◽  
Asif Iqbal ◽  
...  
2020 ◽  
Vol 5 (4) ◽  
pp. 202-209
Author(s):  
Alexander Topal ◽  
◽  
Iryna Holenko ◽  
Luidmyla Haponych ◽  
◽  
...  

For the municipal solid waste (MSW) to be used in a proper way, it is necessary to implement clean technologies capable of thermal treatment of MSW and RDF in order to produce heat and electricity while meeting current ecological requirements. Nowadays, a number of technologies for MSW/RDF thermal treating are being used worldwide. Among them, the most proven technologies, applicable for industrial introduction, have been considered while analyzing their advantages/ disadvantages accounting for local conditions of Ukraine.


1997 ◽  
Vol 35 (8) ◽  
pp. 231-238 ◽  
Author(s):  
Tay Joo Hwa ◽  
S. Jeyaseelan

Conditioning of sludges improves dewatering characteristics and reduces the quantity of sludge to be handled. Anaerobic digested sludge collected from a sewage treatment plant contained 1.8% to 8% oil. The increase of specific resistance and capillary suction time (CST) with increasing oil content observed in these samples indicates the interference of oil in dewatering. It has been found that addition of municipal solid wastes incinerator fly ash decreases the specific resistances and capillary suction times of oily sludges rapidly up to 3% dosage. Beyond 3% fly ash, the decrease is less significant and the solids content in the sludge cake increases. This optimum dosage remains the same for sludges with varying oil contents from 1.8% to 12%. The total suspended solids of filtrate decreases with fly ash dosage but the toxic concentrations of heavy metals increases considerably. However at the optimum dosage of 3%, concentrations of heavy metals are within the limits for discharging into the sewers. The correlations of CST with the dewatering characteristics such as specific resistance, filter yield and corrected filter yield are established. These correlations can be used to obtain a quick prediction on dewaterability.


2009 ◽  
Vol 191 (9) ◽  
pp. 3050-3058 ◽  
Author(s):  
Sadanobu Abe ◽  
Ayako Yasumura ◽  
Teruo Tanaka

ABSTRACT Expression of the gene for the extracellular alkaline protease (aprE) of Bacillus subtilis is subject to regulation by many positive and negative regulators. We have found that aprE expression was increased by disruption of the glutamine synthetase gene glnA. The increase in aprE expression was attributed to a decreased in expression of scoC, which encodes a negative regulator of aprE expression. The glnA effect on scoC expression was abolished by further disruption of tnrA, indicating that aprE expression is under global regulation through TnrA. In the scoC background, however, aprE expression was decreased by glnA deletion, and it was shown that the decrease was due to a defect in positive regulation by DegU. Among the genes that affect aprE expression through DegU, the expression of degR, encoding a protein that stabilizes phosphorylated DegU, was inhibited by glnA deletion. It was further shown that the decrease in degR expression by glnA deletion was caused by inhibition of the expression of sigD, encoding the σD factor, which is required for degR expression. In accordance with these findings, the expression levels of aprE-lacZ in glnA scoC degR and scoC degR strains were identical. These results led us to conclude that glnA deletion brings about two effects on aprE expression, i.e., a positive effect through inhibition of scoC expression and a negative effect through inhibition of degR expression, with the former predominating over the latter.


2021 ◽  
Vol 13 (3) ◽  
pp. 1462
Author(s):  
Faisal A. Osra ◽  
Huseyin Kurtulus Ozcan ◽  
Jaber S. Alzahrani ◽  
Mohammad S. Alsoufi

In many countries, open dumping is considered the simplest, cheapest, and most cost-effective way of managing solid wastes. Thus, in underdeveloped economies, Municipal Solid Wastes (MSW) are openly dumped. Improper waste disposal causes air, water, and soil pollution, impairing soil permeability and blockage of the drainage system. Solid Waste Management (SWM) can be enhanced by operating a well-engineered site with the capacity to reduce, reuse, and recover MSW. Makkah city is one of the holiest cities in the world. It harbors a dozen of holy places. Millions of people across the globe visit the place every year to perform Hajj, Umrah, and tourism. In the present study, MSW characterization and energy recovery from MSW of Makkah was determined. The average composition of solid waste in Makkah city is organic matter (48%), plastics (25%), paper and cardboard (20%), metals (4%), glass (2%), textiles (1%), and wood (1%). In order to evaluate energy recovery potential from solid waste in Kakia open dumpsite landfill, the Gas Generation Model (LandGEM) was used. According to LandGEM results, landfill gas (methane and carbon dioxide) generation potential and capacity were determined. Kakia open dump has a methane potential of 83.52 m3 per ton of waste.


2015 ◽  
Vol 78 ◽  
pp. 185-195 ◽  
Author(s):  
Nuno Couto ◽  
Valter Silva ◽  
Eliseu Monteiro ◽  
Sandra Teixeira ◽  
Ricardo Chacartegui ◽  
...  

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