Faculty of Applied Sciences
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Item 7 Unlocking nature’s remediation arsenal : the role of polyphenol oxidases in efficient and eco-friendly industrial wastewater treatment(De Gruyter, 2024-04-08) Nagarajan, Prithiviraj; Rajathy, Leena; Patil, Sharangouda J.; Golla, Narasimha; Krishna, Suresh Babu NaiduPhenol and its derivatives have gained considerable attention recently due to their high toxicity, teratogenicity, and mutagenicity. Petroleum refinery wastewater is a significant source of phenolic compounds. However, conventional techniques used to treat these wastewaters have several drawbacks, such as incomplete or inefficient removal of phenols. In contrast, biocatalytic processes have garnered significant attention as they offer sustainable and effective removal of toxins, including phenols, from wastewater. Among various biocatalysts, polyphenol oxidases have emerged as major biocatalytic enzymes. These enzymes contain copper and catalyze the oxidation of specific phenolic substrates to quinones in the presence of molecular oxygen. Polyphenol oxidases have a wide range of applications. In the food industry, they are utilized for cocoa and tea production, enhancing coffee flavor and assessing food quality. In medicine, they find applications in treating phenylketonuria, Parkinson's disease, and leukemia. In environmental technology, they play a crucial role in removing phenolic pollutants from industrial wastewater. In the pharmaceutical industry, polyphenol oxidase-immobilized electrodes differentiate between morphine and codeine. This chapter provides comprehensive details about polyphenol oxidases' structure, biochemical properties, and applications, specifically focusing on their role in wastewater treatment.Item 12 Polyphenol oxidases : the future toward global sustainability(De Gruyter, 2024-04-08) Harun-Ur-Rashid, Mohammad; Krishna, Suresh Babu Naidu; Golla, Narasimha; Bin Imran, AbuPolyphenol oxidases (PPOs) are enzymes that catalyze the oxidation of phenolic compounds, which are abundant in many plant-based foods. PPOs are crucial in postharvest losses and food waste, especially in developing countries with underdeveloped food supply chains. There has been a growing interest in utilizing PPOs for sustainable food production and preservation, modifying phenolic compounds to develop new food products, detecting phenolic compounds in various products, and utilizing bioremediation, agriculture, biotechnology, and waste management techniques to promote global sustainability. These advances have the potential to provide effective solutions toward achieving a more sustainable future. The most promising application of PPOs for achieving global sustainability is their use as a natural preservative to prolong the shelf life of fresh produce. They can be used to produce novel food products, such as functional foods and nutraceuticals, by modifying the phenolic compounds. The approach can add value to the food industry by creating new products with health benefits and reducing waste. PPOs can be used in bioremediation processes to degrade phenolic compounds found in industrial wastewater and produce natural antioxidants from food waste, promoting circular economy principles. They can also contribute to sustainable agriculture by increasing plant resistance to pests and diseases, reducing synthetic pesticides and herbicides, and improving crop yields. Overall, PPOs have a promising role in creating a more sustainable environment. This chapter thoroughly examines the latest developments in utilizing PPOs for sustainable food production and waste management. It emphasizes the enzyme's potential in natural preservation, novel food production, bioremediation, and sustainable agriculture. Additionally, the authors explore the wide range of applications for PPOs, such as biosensors, bioremediation, agriculture, and biotechnology.Item Green synthesis of silver nanoparticles from Hibiscus tiliaceus L. Leaves and their applications in dye degradation, antioxidant, antimicrobial, and anticancer activities(Elsevier BV, 2024-05) Konduri, Vinay Viswanath; Kalagatur, Naveen Kumar; Gunti, Lokanadhan; Mangamuri, Usha Kiranmayi; Kalagadda, Venkateswara Rao; Poda, Sudhakar; Krishna, Suresh Babu NaiduThe present study reports the green synthesis of silver nanoparticles (AgNPs) from aqueous extract of Hibis cus tiliaceus L. leaves and their application in dye degradation, antioxidant, antimicrobial, and anticancer activities. Analysis using Fourier transform infrared (FT-IR) spectroscopy revealed that plant metabolite func tional groups had a role in the reduction and stability of AgNPs, and X-ray crystallography (XRD) demon strated that the AgNPs were in crystal form. The UV vis spectroscopy, dynamic light scattering (DLS), and zeta potential investigations revealed that the AgNPs were formed with an average size of 88.10 nm in colloi dal form and were stable (-49 mV). The field emission scanning electron microscopy (FE-SEM) and high-reso lution transmission electron microscopy (HR-TEM) confirmed the shape and size of the AgNPs as spherical with a particle size of 30 - 35 nm, respectively. The AgNPs exhibited potential antioxidant activity by total antioxidant, DPPH, and reducing power assays. The biosynthesized AgNPs displayed a wide range of antibac terial activity on Gram-ve and Gram+ve bacteria by the zone of inhibition assay. AgNPs showed good antican cer activity on MCF-7 cells with an IC50 value of 65.83 mg/mL. Furthermore, AgNPs acted as potential catalysts in combination with the reducing agent sodium borohydride (NaBH4) for the degradation of methylene blue (MB), methylene orange (MO), and methylene green (MG) dyes. The degradation efficiency of catalyst AgNPs in the attendance of NaBH4 for 15 min was noted to be 12.8 %, 26.92 %, and 47.56 % for MO, MB, and MG, respectively. The study concluded that green synthesized AgNPs could be highly applicable as an antioxidant, antimicrobial, and anticancer agents in the biomedical field. Furthermore, AgNPs could be helpful in the remediation of dye effluents.Item ZnO based 0-3D diverse nano-architectures, films and coatings for biomedical applications(Royal Society of Chemistry (RSC), 2024) Krishna, Suresh Babu Naidu; Jakmunee, Jaroon; Mishra, Yogendra K.; Prakash, JaiThin-film nano-architecting is a promising approach that controls the properties of nanoscale surfaces to increase their interdisciplinary applications in a variety of fields. In this context, zinc oxide (ZnO)-based various nano-architectures (0–3D) such as quantum dots, nanorods/nanotubes, nanothin films, tetrapods, nanoflowers, hollow structures, etc. have been extensively researched by the scientific community in the past decade. Owing to their unique surface, charge transport, optoelectronic properties, and reported biomedical applications, ZnO has been considered one of the most important futuristic bio-nanomaterials. This review is focused on the design/synthesis and engineering of 0–3D nano-architecture ZnO-based thin films and coatings with tunable characteristics for multifunctional biomedical applications. Although ZnO has been extensively researched, ZnO thin films composed of 0–3D nanoarchitectures with promising thin film device bio-nanotechnology applications have rarely been reviewed. The current review focuses on important details about the technologies used to make ZnO-based thin films, as well as the customization of properties related to bioactivities, characterization, and device fabrication for modern biomedical uses that are relevant. It features biosensing, tissue engineering/wound healing, antibacterial, antiviral, and anticancer activity, as well as biomedical diagnosis and therapy with an emphasis on a better understanding of the mechanisms of action. Eventually, key issues, experimental parameters and factors, open challenges, etc. in thin film device fabrications and applications, and future prospects will be discussed, followed by a summary and conclusion.Item Antioxidant potential of zephyranthes citrina seed extract in saccharomyces cerevisiae’s oxidative stress response system(Association of Biotechnology and Pharmacy, 2023-10-15) Patil, Sharangouda J.; Jyothi, Renuka; Sadashiv, S. O.; Vishwantaha, T.; Adam, Jamila Khatoon; Krishna, Suresh Babu NaiduItem Enhancing the mechanical properties of hydrogels with vinyl-functionalized nanocrystalline cellulose as a green crosslinker(IOP Publishing, 2023-12-10) Islam, Hasanul Banna Muhammad Zukaul; Krishna, Suresh Babu Naidu; Bin Imran, AbuHydrogels have gained significant attention in scientific communities for their versatile applications, but several challenges need to be addressed to exploit their potential fully. Conventional hydrogels suffer from poor mechanical strength, limiting their use in many applications. Moreover, the crosslinking agents used to produce them are often toxic, carcinogenic, and not bio-friendly. This study presents a novel approach to overcome these limitations by using bio-friendly modified nanocrystalline cellulose as a crosslinker to prepare highly stretchable and tough thermosensitive hydrogels. The surface of nanocrystalline cellulose was modified with 3-methacryloxypropyltrimethoxysilane (MPTS) to obtain modified nanocrystalline cellulose (M-NCC) crosslinker and used during free radical polymerization of thermosensitiveN-isopropyl acrylamide (NIPA) monomer to synthesize NIPA/M-NCC hydrogel. The resulting nanocomposite hydrogels exhibit superior mechanical, thermal, and temperature-responsive swelling properties compared to conventional hydrogels prepared with traditional bi-functionalN,N'-methylene bis (acrylamide) (MBA) as a crosslinker. The elongation at break, tensile strength, and toughness of the NIPA/M-NCC hydrogels significantly increase and Young's modulus decrease than conventional hydrogel. The designed M-NCC crosslinker could be utilized to improve the mechanical strength of any polymeric elastomer or hydrogel systems produced through chain polymerization.Item The future of graphene oxide-based nanomaterials and their potential environmental applications: a contemporary view(Springer International Publishing, 2023) Chakroborty, Subhendu; Panda, Pravati; Krishna, Suresh Babu Naidu; Prakash, Jai; Junghuyn, Cho; Janegitz, Bruno Campos; Shuhui, SunEnvironmental safety is vital to life on Earth. Environment and life are interconnected like two sides of a coin. Pollution is a serious challenge in both developing and developed nations. Rapid rise in human civilization, together with metrological works and industrialization, affects the environment. Due to the excessive release of heavy metal ions, air, water, and soil-borne diseases as corona, cholera, cardiovascular issues, chronic conditions, and cancer increase. Different research organizations use several ways to combat environmental problems. Nanotechnology-based solutions are cost-effective and efficient. Nanomaterials’ multifaceted applications revolutionize science. Its particle-to-size ratio gives a wide surface area with several reactive sites. Carbon-based nanomaterials like graphene, fullerene, carbon nanotubes, graphene oxide, carbon-based quantum dots, etc., have received a lot of attention due to their application to combat environmental issues. Through this chapter, we want to draw researchers’ and academics’ attention to recent trends and applications of graphene oxide based photocatalysts in degradation of organic dye pollutants, biomedical significance, challenges, and future perspectives which will improve the development and application of more multidimensional nanomaterials to human health and for the development of biodiagnostics.Item Palladium immobilized on guanidine functionalized magnetic nanoparticles : a highly effective and recoverable catalyst for ultrasound aided Suzuki-Miyaura cross-coupling reactions(Royal Society of Chemistry (RSC), 2023-10-16) Hegde, Sumanth; Nizam, Aatika; Vijayan, Ajesh; Dateer, Ramesh B.; Krishna, Suresh Babu NaiduWe designed and prepared a palladium catalyst that can be magnetically recyclable by anchoring guanidine moiety on the surface of Fe3O4 nanoparticles, named Fe3O4@SiO2-TCT-Gua-Pd. It was established to be a potent catalyst for the Suzuki–Miyaura cross-coupling reaction (SMCR) in the EtOH/ H2O system under ultrasonic conditions. FT-IR spectroscopy, field-emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) microanalysis, vibration sample magnetometry (VSM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), and inductively coupled plasma atomic emission spectrometry (ICP-AES) analyses were used to characterize the structure of the Fe3O4@SiO2-TCT-Gua-Pd nanoctalyst. The Fe3O4@SiO2-TCT Gua-Pd catalyst produced favorable coupled products with excellent yields and was harmonious with various aryl halides and aryl boronic acids. The stability, low palladium leaching, and heterogeneous nature of the nanocatalyst were confirmed by a hot-filtration test. The palladium nanocatalyst could be easily recovered by magnetic field separation and recycled at least 6 times in a row without noticeable loss in its catalytic activity.Item Biogenic synthesis of zinc oxide nanoparticles mediated by the extract of Terminalia catappa fruit pericarp and its multifaceted applications(American Chemical Society (ACS), 2023-10-09) Fernandes, Cannon Antony; Jesudoss M, Nameeta; Nizam, Aatika; Krishna, Suresh Babu Naidu; Lakshmaiah, Vasantha VeerappaZinc oxide nanoparticles (ZnO-NPs) were bio synthesized by using the pericarp aqueous extract from Terminalia catappa Linn. These NPs were characterized using various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet (UV) spec troscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM), and XRD studies of the nanoparticles reported mean size as 12.58 nm nanocrystals with highest purity. Further SEM analysis emphasized the nanoparticles to be spherical in shape. The functional groups responsible for capping and stabilizing the NPs were identified with FTIR studies. DLS studies of the synthesized NPs reported ζ potential as −10.1 mV and exhibited stable colloidal solution. These characterized ZnO-NPs were evaluated for various biological applications such as antibacterial, antifungal, antioxidant, genotoxic, biocompatibility, and larvicidal studies. To explore its multidimensional application in the field of medicine. NPs reported a potential antimicrobial activity at a concentration of 200 μg/mL against bacterial strains in the decreasing order of Streptococcus pyogenes > Streptococcus aureus > Streptococcus typhi > Streptococcus aeruginosa and against the fungi Candida albicans. In vitro studies of RBC hemolysis with varying concentrations of NPs confirm their biocompatibility with IC50 value of 211.4 μg/mL. The synthesized NPs’ DPPH free radical scavenging activity was examined to extend their antioxidant applications. The antiproliferation and genetic toxicity were studied with meristematic cells of Allium cepa reported with mitotic index (MI index) of 1.2% at the concentration of 1000 μg/mL. NPs exhibited excellent Larvicidal activity against Culex quinquefasciatus larvae with the highest mortality rate as 98% at 4 mg/L. Our findings elicit the therapeutic potentials of the synthesized zinc oxide NPsItem Studies on phytochemical screening, GC-MS analysis and their antibacterial property against Vibrio cholerae(2023-10-05) Guru Prasad, V.; Kuruvalli, Gouthami; Lavanya, L.; Krishna, Suresh Babu Naidu; Imran, Khalid; Reddy, Vaddi DamodaraIn the current study, two different MTCC strains of Vibrio cholera, 3904 and 3906, were used to determine the anti-bacterial properties of Cinnamomum verum (C. verum) leaves (Family: Lauraceae). This was done through qualitative phytochemical compound screening and quantitative identification of volatile compounds using gas chromatography and mass spectrometry (GC-MS). Methanolic extract was subjected to phytochemical screening in order to determine the active components. Through qualitative examination revealed that the substance contained alkaloids, total carbohydrates, cardiac glycosides, flavonoids, glycosides, phenols, saponins, and tannins. Due to the abundance of phytochemical agents in the extract, GC-MS experiments were conducted. Based on their retention times and coverage percentages in mass spectra, these studies identified 42 volatile chemicals. The maximum zone of inhibition for the antibacterial activity of methanol extract were 15.9 mm for the V. cholera MTCC 3904 strain and 16.3 mm for the V. cholera MTCC 3906 strain, respectively, at concentrations of 100μL, Azithromycin showed 22.30 mm, a positive control, at a dosage of 30μg. Total antibacterial activity was determined to be 15.05 ±1.15 mm and 15.10±1.15 mm, respectively, in the examined bacterial strains. These values are equivalent to conventional azithromycin. In conclusion, C. verum can be a potential therapeutic agent against V. cholera strains, this is due to strong antibacterial nature of active biomolecules present in the medicinal plant.
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