Production of amylases by fungi under solid-state fermentation is considered the best methodology for commercial scaling that addresses the ever-escalating needs of the worldwide enzyme market. Here response surface methodology (RSM) was used for the optimization of process variables for α-amylase enzyme production from Trichoderma virens using watermelon rinds (WMR) under solid-state fermentation (SSF). The statistical model included four variables, each detected at two levels, followed by model development with partial purification and characterization of α-amylase. The partially purified α-amylase was characterized with regard to optimum pH, temperature, kinetic constant, and substrate specificity. The results indicated that both pH and moisture content had a significant effect (P < 0.05) on α-amylase production (880 U/g) under optimized process conditions at a 3-day incubation time, moisture content of 50%, 30 °C, and pH 6.98. Statistical optimization using RSM showed R2 values of 0.9934, demonstrating the validity of the model. Five α-amylases were separated by using DEAE-Sepharose and characterized with a wide range of optimized pH values (pH 4.5-9.0), temperature optima (40-60 °C), low Km values (2.27-3.3 mg/mL), and high substrate specificity toward large substrates. In conclusion, this study presents an efficient and green approach for utilization of agro-waste for production of the valuable α-amylase enzyme using RSM under SSF. RSM was particularly beneficial for the optimization and analysis of the effective process parameters.
Marine microorganisms represent virtually unlimited sources of novel biological compounds and can survive extreme conditions. Cellulases, a group of enzymes that are able to degrade cellulosic materials, are in high demand in various industrial and biotechnological applications, such as in the medical and pharmaceutical industries, food, fuel, agriculture, and single-cell protein, and as probiotics in aquaculture. The cellulosic biopolymer is a renewable resource and is a linearly arranged polysaccharide of glucose, with repeating units of disaccharide connected via β-1,4-glycosidic bonds, which are broken down by cellulase. A great deal of biodiversity resides in the ocean, and marine systems produce a wide range of distinct, new bioactive compounds that remain available but dormant for many years. The marine environment is filled with biomass from known and unknown vertebrates and invertebrate microorganisms, with much potential for use in medicine and biotechnology. Hence, complex polysaccharides derived from marine sources are a rich resource of microorganisms equipped with enzymes for polysaccharides degradation. Marine cellulases' extracts from the isolates are tested for their functional role in degrading seaweed and modifying wastes to low molecular fragments. They purify and renew environments by eliminating possible feedstocks of pollution. This review aims to examine the various types of marine cellulase producers and assess the ability of these microorganisms to produce these enzymes and their subsequent biotechnological applications.
An increase in temperature can have a profound effect on the cell cycle and cell division in green algae, whereas growth and the synthesis of energy storage compounds are less influenced. In Chlamydomonas reinhardtii, laboratory experiments have shown that exposure to a supraoptimal temperature (39 °C) causes a complete block of nuclear and cellular division accompanied by an increased accumulation of starch. In this work we explore the potential of supraoptimal temperature as a method to promote starch production in C. reinhardtii in a pilot-scale photobioreactor. The method was successfully applied and resulted in an almost 3-fold increase in the starch content of C. reinhardtii dry matter. Moreover, a maximum starch content at the supraoptimal temperature was reached within 1-2 days, compared with 5 days for the control culture at the optimal temperature (30 °C). Therefore, supraoptimal temperature treatment promotes rapid starch accumulation and suggests a viable alternative to other starch-inducing methods, such as nutrient depletion. Nevertheless, technical challenges, such as bioreactor design and light availability within the culture, still need to be dealt with.
- MeSH
- biomasa * MeSH
- bioreaktory MeSH
- buněčný cyklus MeSH
- Chlamydomonas reinhardtii metabolismus MeSH
- fotobioreaktory * MeSH
- kultivační média MeSH
- mikrořasy MeSH
- průmyslová mikrobiologie metody MeSH
- škrob metabolismus MeSH
- světlo MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Fructosyltransferase (FTase) catalyzes the transfer of a fructosyl group to a sucrose molecule or a fructooligosaccharide (FOS) when a FOS with a longer chain is formed. Production of FTase by two Aspergillus species and its mixture was exploited using solid-state fermentation (SSF) and employing agave sap as substrate. The maximum FTase activity (1.59 U/mL) by Aspergillus oryzae was obtained after 24 h, using a temperature of 30 °C, with an inoculum of 2 × 107 spores/mL. The nucleotide sequence coding for the fructosyltransferase showed 1494 bp and encodes for a protein of 498 amino acids. The hypothetical molecular tertiary structure of Aspergillus oryzae BM-DIA FTase showed the presence of structural domains, such as a five-bladed beta-propeller domain characteristic of GH (glycoside hydrolase) and C terminal, which forms a beta-sandwich module. This study contributes to the knowledge of stability, compatibility, and genetic expression of Aspergillus oryzae BM-DIA under SSF bioprocess conditions for industrial production of fructosyltransferase.
Enzymes of microbial origin are of immense importance for organic material decomposition leading to bioremediation of organic waste, bioenergy generation, large-scale industrial bioprocesses, etc. The market demand for microbial cellulase enzyme is growing more rapidly which ultimately becomes the driving force towards research on this biocatalyst, widely used in various industrial activities. The use of novel cellulase genes obtained from various thermophiles through metagenomics and genetic engineering as well as following metabolic engineering pathways would be able to enhance the production of thermophilic cellulase at industrial scale. The present review is mainly focused on thermophilic cellulolytic bacteria, discoveries on cellulase gene, genetically modified cellulase, metabolic engineering, and their various industrial applications. A lot of lacunae are yet to overcome for thermophiles such as metagenome analysis, metabolic pathway modification study, search of heterologous hosts in gene expression system, and improved recombinant strain for better cellulase yield as well as value-added product formation.
Anaerobic microorganisms (anaerobes) possess a fascinating metabolic versatility. This characteristic makes anaerobes interesting candidates for physiological studies and utilizable as microbial cell factories. To investigate the physiological characteristics of an anaerobic microbial population, yield, productivity, specific growth rate, biomass production, substrate uptake, and product formation are regarded as essential variables. The determination of those variables in distinct cultivation systems may be achieved by using different techniques for sampling, measuring of growth, substrate uptake, and product formation kinetics. In this review, a comprehensive overview of methods is presented, and the applicability is discussed in the frame of anaerobic microbiology and biotechnology.
The full biotechnological exploitation of thermostable enzymes in industrial processes is necessary for their commercial interest and industrious value. The heat-tolerant and heat-resistant enzymes are a key for efficient and cost-effective translation of substrates into useful products for commercial applications. The thermophilic, hyperthermophilic, and microorganisms adapted to extreme temperatures (i.e., low-temperature lovers or psychrophiles) are a rich source of thermostable enzymes with broad-ranging thermal properties, which have structural and functional stability to underpin a variety of technologies. These enzymes are under scrutiny for their great biotechnological potential. Temperature is one of the most critical parameters that shape microorganisms and their biomolecules for stability under harsh environmental conditions. This review describes in detail the sources of thermophiles and thermostable enzymes from prokaryotes and eukaryotes (microbial cell factories). Furthermore, the review critically examines perspectives to improve modern biocatalysts, its production and performance aiming to increase their value for biotechnology through higher standards, specificity, resistance, lowing costs, etc. These thermostable and thermally adapted extremophilic enzymes have been used in a wide range of industries that span all six enzyme classes. Thus, in particular, target of this review paper is to show the possibility of both high-value-low-volume (e.g., fine-chemical synthesis) and low-value-high-volume by-products (e.g., fuels) by minimizing changes to current industrial processes.
Endo-glucanase (cellulase) and xylanase have high industrial demand due to their vast application in industrial processes. This study reports statistical based experimental optimization for co-production of endo-glucanase and xylanase from Bacillus sonorensis BD92. Response surface methodology (RSM) involving central composite design (CCD) with full factorial experiments (23) was applied to elucidate the components that significantly affect co-production of endo-glucanase and xylanase. The optimum co-production conditions for endo-glucanase and xylanase were as follows: carboxymethyl cellulose (CMC) 20 g/L, yeast extract 15 g/L, and time 72 h. The maximum endo-glucanase and xylanase production obtained was 1.46 and 5.69 U/mL, respectively, while the minimum endo-glucanase and xylanase production obtained was 0.66 and 0.25 U/mL, respectively. This statistical model was efficient because only 20 experimental runs were necessary to assess the highest production conditions, and the model accuracy was very satisfactory as coefficient of determination (R2) was 0.95 and 0.89 for endo-glucanase and xylanase, respectively. Further, potential application of these enzymes for saccharification of lignocellulosic biomass (wheat bran, wheat straw, rice straw, and cotton stalk) was also investigated. The results revealed that the biomass was susceptible to enzymatic saccharification and the amount of reducing sugars (glucose and xylose) increased with increase in incubation time. In conclusion, Bacillus sonorensis BD92 reveals a promise as a source of potential endo-glucanase and xylanase producer that could be useful for degrading plant biomass into value-added products of economic importance using precise statistically optimized conditions.
- MeSH
- Bacillus růst a vývoj metabolismus MeSH
- biomasa * MeSH
- celulasa biosyntéza MeSH
- endo-1,4-beta-xylanasy biosyntéza MeSH
- fermentace MeSH
- hydrolýza MeSH
- průmyslová mikrobiologie metody MeSH
- rýže (rod) metabolismus MeSH
- sodná sůl karboxymethylcelulosy MeSH
- statistické modely MeSH
- Publikační typ
- časopisecké články MeSH
Simpler and biocompatible greener approaches for the assembly of nanoparticles (NPs) have been the focus lately which have minimum environmental damage and often entails the use of natural biomolecules to synthesize NPs. Such greener synthesis of nanoparticles has capitalized on the use of microbes, fungi, and plants using biological resources. In this study, Periplaneta americana (American cockroach) wings' extract (chitin-rich) is studied as a novel biomaterial for the first time to synthesize silver NPs (less than 50 nm); chitin is the second most abundant polymer after cellulose on earth. The physicochemical properties of these NPs were analyzed using UV-visible spectroscopy, X-ray diffraction, and transmission electron microscopy (TEM). The insecticidal effect of ensuing NPs was examined on the mortality of Aphis gossypii under laboratory conditions; 48 h after treatments of A. gossypii with silver NPs (100 μg/ml), the mortality rate in treated aphids was about 40% (an average), while an average percentage of losses in the control sample was about 10%. These results indicate the lethal effect of green-synthesized silver NPs on A. gossypii, in vitro. Greener synthesis of silver nanoparticles using American cockroach wings and their insecticidal activities.
- MeSH
- biokompatibilní materiály chemie MeSH
- celulosa chemie MeSH
- chitin chemie MeSH
- difrakce rentgenového záření MeSH
- insekticidy farmakologie MeSH
- kovové nanočástice chemie MeSH
- křídla zvířecí chemie MeSH
- Periplaneta chemie MeSH
- polymery chemie MeSH
- průmyslová mikrobiologie metody MeSH
- spektrofotometrie ultrafialová MeSH
- stříbro chemie MeSH
- technologie zelené chemie metody MeSH
- transmisní elektronová mikroskopie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Quercetin is a flavonoid largely employed as a phytochemical remedy and a food or dietary supplement. We present here a novel biocatalytic methodology for the preparation of quercetin from plant-derived rutin, with both substrate and product being in mostly an undissolved state during biotransformation. This "solid-state" enzymatic conversion uses a crude enzyme preparation of recombinant rutinosidase from Aspergillus niger yielding quercetin, which precipitates from virtually insoluble rutin. The process is easily scalable and exhibits an extremely high space-time yield. The procedure has been shown to be robust and was successfully tested with rutin concentrations of up to 300 g/L (ca 0.5 M) at various scales. Using this procedure, pure quercetin is easily obtained by mere filtration of the reaction mixture, followed by washing and drying of the filter cake. Neither co-solvents nor toxic chemicals are used, thus the process can be considered environmentally friendly and the product of "bio-quality." Moreover, rare disaccharide rutinose is obtained from the filtrate at a preparatory scale as a valuable side product. These results demonstrate for the first time the efficiency of the "Solid-State-Catalysis" concept, which is applicable virtually for any biotransformation involving substrates and products of low water solubility.
- MeSH
- Aspergillus niger enzymologie genetika MeSH
- biokatalýza * MeSH
- disacharidy chemie metabolismus MeSH
- fungální proteiny genetika metabolismus MeSH
- glykosidhydrolasy genetika metabolismus MeSH
- Pichia genetika metabolismus MeSH
- průmyslová mikrobiologie metody MeSH
- quercetin chemie metabolismus MeSH
- rutin chemie metabolismus MeSH
- Publikační typ
- časopisecké články MeSH