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Composting: Programs, Process, and Product
Published in Robert E. Landreth, Paul A. Rebers, Municipal Solid Wastes, 2020
Lynnann Hitchens, Richard M. Kashmanian
Like pH, temperature is not usually a controlled variable, but is an indicator of the microbial activity existing in the decomposing mass. Both mesophilic and thermophilic organisms are necessary for successful composting and these organisms are naturally present in organic material. Mesophilic microorganisms grow best at temperatures between 25 and 45°C.20 As the microorganisms metabolize the organic matter, generating carbon dioxide and water, the temperature of the composting mass rises. Under less than optimal temperatures, the mesophiles become dormant. Thermophilic microorganisms prefer temperatures between 45 and 70°C.20 So, as the temperature of the composting pile rises, the thermophilic microorganisms dominate. The phase in which the thermophiles are generating heat is the point at which pathogens are destroyed. Time and temperature are necessary to ensure that pathogens are destroyed. Thermophilic decomposition continues as long as sufficient nutrients and oxygen exist.
Leaching, bioleaching, and acid mine drainage case study
Published in Katalin Gruiz, Tamás Meggyes, Éva Fenyvesi, Engineering Tools for Environmental Risk Management – 4, 2019
H.M. Siebert, G. Florian, W. Sand, E. Vaszita, K. Gruiz, M. Csővári, G. Földing, Zs. Berta, J.T. Árgyelán
The composition of leaching communities depends on environmental conditions such as temperature, humidity, heavy metal concentration and substrate conditions. Leaching communities consist of diverse acidophilic bacterial and archaeal species. Chemolithotrophic bacteria like Leptospirillum spp., Acidithiobacillus spp., and archaea such as Sulfolobus spp. or Metallosphaera spp. have been isolated from sites of natural mineral oxidation (Temple & Colmer, 1951; Sand et al., 1992; Kelly & Wood, 2000; Schippers, 2007). Acid-tolerant chemoorganotrophic bacteria such as Acidiphilum spp. are also present in bioleaching communities (Harrison, 1984; Nancucheo & Johnson, 2009). Microorganisms have been subdivided into three groups according to preferred growth temperature ranges. Mesophilic organisms are those with optimum temperatures between 25°C and 40°C, e.g. Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, or Leptospirillum ferrooxidans. They cannot grow above 45°C (Rawlings, 1997). Moderate thermophilic microorganisms such as Leptospirillum ferriphilum, Sulfobacillus thermosulfidooxidans, or Ferroplasma acidarmanus can grow in mixed cultures with mesophiles or with thermophiles. The temperatures for moderate thermophiles range between 40°C and 55°C (Norris, 1997). Thermophilic archaea such as Acidianus brierleyi or Sulfolobus metallicus can grow at temperatures between 55°C and 80°C (Clark & Norris, 1996; Zhu et al., 2011).
Industrial biotechnology
Published in Firdos Alam Khan, Biotechnology Fundamentals, 2018
Thermophiles are microorganisms that live and grow in extremely hot environments that would kill most other microorganisms. Thermophiles are grouped into either prokaryotes or eukaryotes, and these two groups of extremophiles are classified in the group of Archaea. They grow best in temperatures between 50°C/120°F and 70°C/158°F. They will not grow if the temperature reaches 20°C/68°F. Thermophiles are not easy to study because of the extreme conditions that they need to survive. Thermophiles either live in geothermal habitats or in environments that themselves create heat. A pile of compost and garbage landfills are two examples of environments that produce heat on their own. Some thermophiles are fungi such as Chaetomium thermophile, Humicola insolens, H. (Thermomyces) lanuginosus, Thermoascus aurantiacus (a Paecilomyces-like fungus), and A. fumigates. Thermus aquaticus and Thermococcus litoralis are two thermophiles that are used as an enzyme in DNA fingerprinting in criminal cases or in identification of parents or siblings. B. stearothermophilus is another thermophile used as an enzyme in biological detergents. Thermophiles in self-heating environments must have a supply of organic matter like food scraps in order to grow. These kinds of thermophiles turn this organic matter into a rich source of nutrients for living microorganisms and plants to use as food.
Modeling and evaluation of the sucrose-degrading activity of recombinantly produced oligo-1,6-glucosidase from A. gonensis
Published in Preparative Biochemistry & Biotechnology, 2023
Hakan Karaoglu, Zeynep Dengız Balta
According to the CAZy database (http://www.cazy.org/), oligo-1,6-glucosidase (O-1-6-glucosidase) (EC 3.2.1.10) is a member of the glycoside hydrolase family 13 subfamily 31 (GH13_31).[10] O-1-6-glucosidase hydrolyzes non-reducing ends of isomaltooligosaccharides, panose, palatinose, and an a-limit dextrin by breaking α-1,6-glucoside bonds, although it generally lacks activity on α-1,4-glucoside bonds of maltooligosaccharides.[11] The enzyme is also called isomaltase, sucrase-isomaltase, dextrin 6-α-D glucanohydrolase, palatinase, and α-limit dextrinase. O-1-6-glucosidase is commonly used in the saccharification step of HFS production because it hydrolyzes branched oligosaccharides of short lengths and increasing glucose yield.[12] O-1-6-glucosidase can also hydrolyze sucrose to its monomers, glucose and fructose (Figure 1), which are valuable for HFS.[13] While, sucrose hydrolyzing activity was not studied for HFS production before, isomaltooligosaccharides hydrolyzing activity of O-1-6-glucosidase has been well-studied.[14] The microorganisms surviving above the temperature of 40 °C are categorized as thermophilic. Thermophilic microorganisms generally inhabit hot springs and have unique metabolites, especially physically and chemically stable enzymes. Recently, thermophilic microorganisms and their enzymes have been extensively researched due to their advantages for industrial applications.[15]
Biotechnological Avenues in Mineral Processing: Fundamentals, Applications and Advances in Bioleaching and Bio-beneficiation
Published in Mineral Processing and Extractive Metallurgy Review, 2023
Srabani Mishra, Sandeep Panda, Ata Akcil, Seydou Dembele
Moderate thermophiles are able to grow at a temperature range of 40–60ºC. They involve microorganisms such as Acidimicrobium ferrooxidans, Acidithiobacillus caldus and Sulphobacillus thermosulphooxidans, Sulfobacillus acidophilus, Sulfobacillus disulfidooxidans, Thermoplasma acidophylum, and Alicyclobacillus acidocaldrius (Justice et al. 2014; Schippers et al. 2014). In addition, microbes belonging to the genus Leptospirillum, e.g., Leptospirillum thermoferrooxidans has an optimum growth temperature of 45ºC with the capability of iron oxidation at 55ºC (Coram and Rawlings 2002). Sulfobacillus thermosulfidooxidans is seen to be one of most important moderate thermophile used in bioleaching. For example, it has been seen that this microorganism can be used successfully for bioleaching of pyrrhotite (an iron-sulphide mineral) at a temperature of 52°C (Ni et al. 2014). This microbe is a chemolithotrophic bacterium which obtains its energy by oxidizing iron, elemental sulfur and sulfur compounds; also having the capability to grow heterotrophically using some organic compounds (Ni et al. 2014). In general, Sulfobacillus species are gram-positive, rod shaped and thermophilic (45–50°C) bacteria that derive their energy from aerobic oxidation of iron and various sulfur species.
Thermophilic bacteria from Peruvian hot springs with high potential application in environmental biotechnology
Published in Environmental Technology, 2022
Luis Felipe Valdez-Nuñez, Marco A. Rivera-Jacinto
Extreme environments such as hot springs are the natural culture media for the development of well-adapted microorganisms suitable for being used in biotechnology. As an example of this, we can find thermophiles, microorganisms with optimal growth temperature of 45°C or higher, whose thermostable enzymes (thermozymes) are valuable resources not only in biocatalysis but also in bioremediation. Biosurfactants [1], siderophores [2], and hydrolases such as PETases, cutinases, lipases, and proteases [3], are some examples of thermozymes with extensive applications in environmental biotechnology. Additionally, phosphatases and oxidoreductases, with potential application in the degradation of phosphate- and aromatic-like compounds, have also been reported in microorganisms isolated from hot spring environments [4]. Currently, different thermophilic bacteria have been retrieved and identified from hot springs worldwide. Bacillus, Paenibacillus, Anoxybacillus, Geobacillus, Lysinibacillus and Brevibacillus are some examples of thermophilic bacterial genera with different applications in biotechnology [1,4–8].