Bioprocessing of Agro-Industrial Waste for Maximization of Pectinase Production by a Novel Native Strain <i>Aspergillus cervinus</i> ARS2 Using Statistical Approach

The demand for microbial pectinase has increased due to its vast applications in different industries. The current study dealt with the synthesis of pectinase by a novel native strain Aspergillus cervinus ARS2 using agro-industrial waste. Comparative studies conducted on pectinase production by submerged fermentation (SmF) and solid-state fermentation (SSF) showed that pectinase activity was more increased in SSF (44.51 ± 1.33 IU/mL) than in SmF (40.60 ± 1.15 IU/mL) when using orange peel as a substrate. Using SSF, one-factor-at-a-time (OFAT) studies were conducted, considering different process variables such as inoculum size, initial pH, incubation time, moisture content, incubation temperature, and substrate particle size, all of which affected the pectinase activity. OFAT results showed the highest pectinase activity at an inoculum size of 106 spores/mL (43.11 ± 1.06 U/mL), an incubation time of 6 days (43.81 ± 1.21 U/mL), a moisture content of 100% (44.30 ± 1.69 U/mL), a substrate particle size of 1.7 mm (42.06 ± 1.20 U/mL), an incubation temperature of 37 °C (45.90 ± 1.33 U/mL), and an initial pH of 4 (43.31 ± 0.89 U/mL). The identified significant process variables were then optimized by response surface methodology (RSM)-central composite design (CCD). The results showed optimum pectinase activity of 107.14 ± 0.71 IU/mL for a substrate particle size of 2 mm, an incubation temperature of 31.5 °C, an initial pH of 4.9, and a moisture content of 107%, which was obtained from the Minitab optimizer. By using statistical optimization, the pectinase production from the isolated novel fungal strain A. cervinus ARS2 was increased 2.38-fold. Therefore, the A. cervinus ARS2 strain can be further explored for large-scale pectinase production which could meet the growing industrial demands

Media Optimization by Response Surface Methodology for the Enhanced Production of Acidic Extracellular Pectinase by the Indigenously Isolated Novel Strain Aspergillus cervinus ARS2 Using Solid-State Fermentation

Pectinolytic enzymes are related enzymes that hydrolyze pectic substances. Pectinolytic enzymes are of great interest in industrial applications for softening fruits, extracting and clarifying juices, extracting olive oil, retting textile fibers, preparing gel, and isolating protoplasts. The current work presents acidic extracellular pectinase production using low-cost agro-industrial waste with the indigenously isolated novel strain Aspergillus cervinus. Two fungal isolates, ARS2 and ARS8, with maximum pectinase activity, 41.88 &plusmn; 1.57 IU/mL and 39.27 &plusmn; 1.14 IU/mL, respectively, were screened out of 27 isolates from decayed fruit peels (orange, banana, and lemon) and soil containing decomposed vegetables. The isolate ARS2, identified as Aspergillus cervinus by molecular characterization, showed the highest pectinase activity of 43.05 &plusmn; 1.38IU/mL during screening and was further used for media component screening and optimization studies. To understand their effect on pectinase activity, one-factor-at-a-time (OFAT) studies were conducted on carbon sources, nitrogen sources, and mineral salts. The OFAT results showed the highest pectinase activity for orange peel (carbon source) at 44.51 &plusmn; 1.33 IU/mL, peptone (nitrogen source) at 45.05 &plusmn; 1.04 IU/mL, and NaH2PO4 (mineral salts) at 43.21 &plusmn; 1.12 IU/mL. The most significant media components screened by the Plackett&ndash;Burman (PB) design based on the p-value, Pareto chart, and main effect plot, were orange peel (p &lt; 0.001), peptone (p &lt; 0.001), NaH2PO4 (p &lt; 0.001), and KH2PO4 (p &lt; 0.001), which were further optimized using Response Surface Methodology (RSM) and Central Composite Design (CCD). The optimization results for the media components showed a maximum pectinase activity of 105.65 &plusmn; 0.31 IU/mL for 10.63 g orange peel, 3.96 g/L peptone, 2.07 g/L KH2PO4, and 2.10 g/L NaH2PO4. Thus, it was discovered that the indigenously isolated novel strain Aspergillus cervinus ARS2 was able to successfully produce a significant amount of pectinase using agro-industrial waste. Therefore, it can be considered for the large-scale optimized production of pectinase to meet industrial demands

Sustainable Synthesis and Characterization of Zinc Oxide Nanoparticles Using <i>Raphanus sativus</i> Extract and Its Biomedical Applications

Zinc Oxide Nanoparticles (ZnONPs) are one of the most widely used metal oxide nanoparticles in biological applications because of their outstanding biocompatibility, affordability, and low toxicity. In biomedicine, ZnONPs have shown promise, particularly in the disciplines of anticancer and antibacterial fields. In comparison to other standard synthesis methods, the environmentally-friendly synthesis of metallic nanoparticles utilizing various plant extracts is a good option. The current research focuses on the synthesis of zinc oxide nanoparticles (ZnONPs) from R. sativus leaf extract under various physical conditions (Precipitation method). Analytical methods were used to confirm and characterize the produced ZnONPs. The spherical nature of the produced nanoparticles was established by SEM analysis. The generation of very pure ZnONPs was confirmed by EDS data. The crystalline nature of the produced nanoparticles, with a particle size of 66.47 nm, was confirmed by XRD. The XRD graphs’ presence of the (100), (002), and (101) planes strongly suggest the production of wurtzite ZnO. The visual and infrared area exhibits transmissions of 84 percent in the pH 10 nanoparticles. The band gap of the nanoparticles increases from 3.34 to 3.38 eV when the pH increases. These nanoparticles were effective against both Gram-positive and Gram-negative bacteria. The effect of several process parameters such as pH and temperature were investigated, and the best conditions were discovered to be pH 12 and 80 °C, respectively. The effect of ZnONPs was tested with human breast cancer cells (MCF-7), and they showed significant cytotoxic results. Collectively, our data suggest that ZnONPs of R. sativus leaf extract inhibit breast cancer cell lines. The ZnONPs are, therefore, a prospective source of chemopreventive drugs that merit additional exploration in order to uncover lead compounds with cancer chemotherapeutic potential

Production of Extracellular Lipase by Bacillus halotolerans from Oil-Contaminated Soil in a Pilot-Scale Submerged Bioreactor

Microbial lipases are the biocatalyst of choice for the present and future because of their characteristics, including their ability to remain active as an enzyme throughout a broad pH, temperature, and substrate range. The goal of the current investigation was to find novel sources of substrates and isolates from soil contaminated by oil for the synthesis of lipase. On tributyrin media, 10 lipolytic bacterial strains that were isolated from oil-contaminated soil were grown. Using the zone of clearance, it was possible to identify the isolates with the highest activity. Following phylogenetic tree analysis, molecular characterization of the 16S rRNA sequence of the bacterial isolates revealed that it was Bacillus halotolerans (VSH 09). The enzyme was purified to near homogeneity. The enzyme activity was found to be optimum at a pH of 7.0 and a temperature of 35 &deg;C. While Ni2+ and Cu2+ had no effect, the presence of Mg2+ and Ca2+ exhibited the highest levels of enzyme activity. At 1%, tributyrin as a substrate exhibited its highest level of activity. The molecular weight, as determined by SDS-PAGE, was found to be 38 kDa. The kinetics of the enzyme were found to be 41.66 and 9.37 mg/mL for Vmax and Km, respectively. The high yield of lipase produced by this method suggests that it holds potential for production on a large scale and could be used for various biotechnological applications