Biohydrogen production coupled with wastewater treatment using selected microalgae.

Microalgae such as Chlorella pyrenoidosa, Scenedesmus obliquus and Chlorella sorokiniana were cultivated in domestic wastewater for biohydrogen production. The comparison between the microalgae was executed based on biomass productions, biochemical yields and nutrient removal efficiencies. S. obliquus showed the possibility of growing in domestic wastewater reaching maximum biomass production, lipid, protein, carbohydrate yield and nutrient removal efficiency. All the three microalgae reached high biomass production of 0.90, 0.76 and, 0.71 g/L, respectively for S. obliquus, C. sorokiniana and C. pyrenoidosa. A higher protein content (35.76%) was obtained in S. obliquus. A similar pattern of lipid yield (25.34-26.23%) and carbohydrate yield (30.32-33.21%) was recorded in all selected microalgae. Chlorophyll-a content was higher in synthetic media-grown algae compared algae grown in wastewater. The maximum nutrient removal efficiencies achieved were 85.54% of nitrate by C. sorokiniana, 95.43% of nitrite by C. pyrenoidosa, ∼100% of ammonia and 89.34% of phosphorus by C. sorokiniana. An acid pre-treatment was applied to disintegrate the biomass of microalgae, followed by dark fermentation in batch mode to produce hydrogen. During fermentation process, polysaccharides, protein and lipids were consumed. Maximum hydrogen production of 45.50 ± 0.32 mLH2/gVS, 38.43 ± 0.42 mLH2/gVS and 34.83 ± 1.82 mL/H2/gVS was achieved by C. pyrenoidosa, S. obliquus and C. sorokiniana respectively. Overall, the results revealed the potential of microalgal cultivation in wastewater coupled with maximum biomass production lead to biohydrogen generation for environmental sustainability.

Design of 1,4-Dihydropyridine Hybrid Benzamide Derivatives: Synthesis and Evaluation of Analgesic Activity and Their Molecular Docking Studies.

Purpose: This study aims to determine the analgesic activity of 1,4-dihydropyridine hybrid benzamide derivatives. These hybrid derivatives were synthesized, and their analgesic activity was studied. The synthesis method applied was a one-step reaction involving a green chemistry approach. Methods: The compounds were prepared via the amination method with a yield ranging between 82% and 93%. The title compounds were confirmed by means of IR, 1H and 13C NMR, and mass spectral analyses. The pharmacological activity of all the synthesized compounds was evaluated, and the analgesic activities were monitored in vivo (by tail immersion methods), with a digital analgesiometer. The drug response and damage of tail ata concentration of 10 mg/kg were measured by tail-flicking latency. Results: The activity of compound 2c (81.35% activity at 5mg/kg) can be correlated with its salicylamidemoiety (13.99% activity at 5mg/kg), and diclofenac showed comparable activity (79.21% activity at 5mg/kg reference drugs). Compound 2c has a higher potential to inhibit COX proteins compared to diclofenac. The drug-like nature of the molecule 2c corresponds to its ADME properties. Conclusion: In this study, all the synthesized compounds were found to possess significant analgesic activities; particularly, the performance of compound 2c is excellent. Thus, the preparative method described is an apt route for developing novel therapeutic formulations.

Solanum pubescens Wild Fruits Essential Oil - A Golden Casket for its Antimicrobial and Anti-inflammatory Mediated Wound Healing Efficacy in Vertebrate Model Mus musculus.

BACKGROUND: Solanum pubescens Willd, growing wild in the hills of Rayadurg jurisdiction of Southwestern Andhra Pradesh, has gained significant attention among researchers for its diverse folkloric applications, existence of novel phytochemicals and leaf extracts which hold great medicinal promises. To date, the S. pubescens fruit's essential oil (SPO) has never been investigated. METHODS: The current research has been focused to evaluate the chemical composition of S. pubescens fruit essential oil through Gas Chromatography-Mass Spectrometry (GC-MS), followed by the investigation of antibacterial, antifungal, anti-inflammatory, analgesic and wound healing activities in appropriate models to uncover its biological potentials. Extraction of (Solanopuboil/SPO) from the fresh unripe fruits of Solanum pubescens was carried out in Buchner funnel and Whatman no.10 filter paper and concentrated at 40°C using a rotary evaporator. The metabolic profiling of SPO was analysed by GC-MS technique. The MIC, MBC, activity index, and total antimicrobial activity of SPO were evaluated using standard procedures. Anti-inflammatory activity of SPO was screened using Carrageenan induced paw oedema and Cotton pellet-induced granuloma. Tail immersion test, Acetic acid writhing response and Formalin paw lick test was performed in rats in order to examine the analgesic activity of SPO. Wound healing activity of SPO was investigated by performing the incision wound model, Excision wound model and Dead space wound model in rats. RESULTS: The SPO displayed a constant degree of antimicrobial activity against B. cereus, B. subtilis, E. coli, A. niger, A. fumigatus and C. albicans with significant anti-inflammatory and analgesic activities. Also, a prominent wound healing potential of it was observed in excision, incision and dead space wound models with considerable elevation in granulation tissue hydroxyproline, hexuronic acid and hexosamine content in association with remarkable regulation of anti-inflammatory and antioxidant markers i.e., Lipid peroxidase (LPO), Nitric Oxide (NO), Superoxide dismutase (SOD), Glutathione (GSH), Catalase (CAT), Glutathione Peroxidase (GPx). CONCLUSION: These findings strongly validate the therapeutic potential of S. pubescens fruit essential oil in antimicrobial and anti-inflammatory mediated wound healing and suggests its promising application as valuable and novel indigenous leads in the food and pharmaceutical industries. To the best of our knowledge, this is the first-ever investigatory report on the systematic phytochemical and therapeutic examination of S. pubescens fruit essential oil.

Statistical optimization of silver nanoparticle synthesis by green tea extract and its efficacy on colorimetric detection of mercury from industrial waste water.

For the optimization of silver nanoparticle production, a central composite design was used with three parameters: AgNO3 concentration, green tea extract concentration, and temperature at three different levels. The size of the synthesized silver nanoparticle, its UV absorbance, zeta potential, and polydispersity index were set as the response parameters. Silver nanoparticles obtained in the optimization process were characterized and its efficacy on colorimetric detection of mercury was evaluated. The response variables were significant for the factors analyzed, and each variable had a significant model (P < 0.05). The ideal conditions were: 1 mM AgNO3, 0.5% green tea extract, and 80 °C temperature. To analyze the produced AgNPs under certain ideal conditions, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used. The UV-visible spectra of AgNPs revealed an absorption maxima at 424 nm. The XRD pattern reveals a significant diffraction peak at 38.25°, 44.26°, 64.43°, and 77.49°, which corresponds to the (111), (200), (220), and (311) planes of polycrystalline face-centered cubic (fcc) silver, respectively. The TEM and SEM analyses confirmed that the particles were spherical, and dynamic light scattering study determined the average diameter of AgNPs to be 77.4 nm. The AgNPs have a zeta potential of -62.6 mV, as determined by the zeta sizer analysis. The AgNPs detects mercury at a micromolar concentration. Furthermore, the environmentally friendly generated AgNPs were used to detect mercury in a colorimetric method that was effectively employed for analytical detection of Hg2+ ions in an aqueous environment for the purpose of practical application.

Synthesis and characterization of proanthocyanidin-chitosan nanoparticles: An assessment on human colorectal carcinoma HT-29 cells.

Cancer nanotheranostic materials are helpful in monitoring drug delivery and efficacy against tumor cells. Current chemotherapeutic may have adverse side effects and this necessity to discover the new modern therapeutic nano-drugs. In the present study, we designed the new targeted and degradable polymer of bio-active chitosan nanoparticles with proanthocyanidin (PAC-CSNPs) and evaluated its apoptotic effects against human colorectal carcinoma cells (HT-29). The functional groups were characterized by Fourier-transform infrared spectroscopy and transmission electron microscope. Further, their dispersion of spherical form nanoparticle with an average size of 73.43 nm used for drug delivery system. The PAC-CSNPs were targeted to inhibit the cyclin-dependent kinases and prevent cell cycle/cell division in cancer cells. At high concentrations of PAC (25 µg/mL) exposure, cell viability of HT-29 cells was greater than 80%. However, at low concentrations of PAC-CSNPs (6.25 µg/mL) exposure, HT-29 cell mortality was high, which may be due to the efficient drug release by CSNPs. The percentage of reactive oxygen species (ROS) levels were 12 ± 2.52% (control), 39 ± 4.32% (PAC), and 85.06 ± 3.54% (PAC-CSNPs). The over production of ROS by PAC-CSNPs can prompt DNA damage, cell death and apoptosis in HT-29 cells. The in vivo toxicity of synthesized PAC-CSNPs was tested against zebra fish observed at dose-time-dependent intervals. In conclusion, the PAC-CSNPs enhanced HT-29 cell death and shows promise as a novel future nano-therapy for cancer.

Two-step system consisting of novel vertical flow and free water surface constructed wetland for effective sewage treatment and reuse.

This study developed a unique system by combining the novel vertical flow (NVF) using expanded clay (ExC) and free flow surface constructed wetland (FWS) for dormitory sewage purification and reuse. The NVF tank consisted of filter layers of ExC, sandy soil, sand, and gravel. The FWS consisted of sandy soil substrate and was installed after the NVF. Colocasia esculenta and Dracaena sanderiana was planted in NVF and FWS, respectively. The treatment system was operated and tested for more than 21 weeks by increasing the hydraulic loading rate (HLR) from 0.02 m/d to 0.12 m/d. The results demonstrated that effluents in the system changed proportionally to the HLRs, except for nitrate nitrogen. Furthermore, the maximum removal efficiencies for TSS, BOD5, NH4-N, and Tcol were 76 ± 13%, 74 ± 11%, 90 ± 3%, and 59 ± 18% (0.37 ± 0.19 log10MPN/100 mL), respectively. At HLRs of 0.04-0.06 m/d, the treatment system satisfied the limits of agriculture irrigation.

A novel protease-immobilized carbon catalyst for the effective fragmentation of proteins in high-TDS wastewater generated in tanneries: Spectral and electrochemical studies.

The aim of this study was to degrade proteins in high-total dissolved solids (TDS)-containing wastewater produced during the soaking process in tanneries (tannery-TDS wastewater) using a halotolerant protease-assisted nanoporous carbon catalyst (STPNPAC). A halotolerant protease was obtained from the halophile, Lysinibacillus macroides, using animal fleshing as the substrate. The protease was immobilized using ethylene diamine (EDA)/glutaraldehyde functionalized nanoporous activated carbon (EGNPAC). The optimum conditions for the immobilization of protease were determined as time (120 min), pH (6), protease concentration (575-600 U/g), EGNPAC size, salinity, and temperature (30 °C). The immobilization was confirmed by FTIR, TGA-DSC, SEM, and XRD analyses. The adsorption kinetics was consistent with a pseudo first order rate constant of 1.43 × 10-2 min-1. The thermodynamic parameters (ΔG, ΔH, and ΔS) confirmed the effective immobilization of the protease onto EGNPAC. STPNAPC was found to efficiently degrade the proteins in tannery-TDS wastewater, with a complete fragmentation time of 90 min at pH 6 and 30 °C. Accordingly, the protein fragmentation was confirmed by UV-visible and UV-fluorescence spectroscopy, ESI-mass spectrometric analysis and circular dichroic studies. The formation of protein hydrolysates was confirmed by cyclic voltammetry and electrical impedance studies. BOD5: COD value, 0.426 of treated tannery-TDS wastewater may favor sequential biological treatment processes.

Environmental friendly synthesis of TiO2-ZnO nanocomposite catalyst and silver nanomaterilas for the enhanced production of biodiesel from Ulva lactuca seaweed and potential antimicrobial properties against the microbial pathogens.

TiO2-ZnO heterogeneous catalytic system provides a good replacement of a homogeneous catalytic reaction due to its easier recovery. In this study, biodiesel was produced from Ulva lactuca seaweeds using TiO2-ZnO nanocomposite catalysts with particle size of ~12 nm. The size controlled TiO2-ZnO nanocomposite was characterized by powder XRD analysis and TEM. The result of that TiO2-ZnO catalyst is a promising catalyst for the production of biodiesel under mild reaction conditions and high yield of hydroxydecanoic acid conversion of 82.8%. The various conditions optimized for the higher conversion to FAME (15.8 ml of FAME) were 4 wt% catalysts at 4 h under 60 °C and further there is no increase of conversion to FAME above 60 °C-80 °C. The total product yield was calculated as 82.8% of conversion to FAME. The evaluated biodiesel was found to be up to the mark of ASTM standards. The silver nanoparticles (AgNPs) were synthesized by using leftover biomass of algae obtaining after lipid extraction of U.lactuca. AgNPs particle size was achieved as ~12 nm and was confirmed by UV-Visible spectroscopy, XRD and TEM analysis. Antibacterial activities of the synthesized AgNPs were analyzed and compared. The antibacterial activity was excellent against bacterial pathogens and treatment against P. vulgaris shows the maximum zone of inhibition (13.8 mm). The present work identified that the unutilized bioresource such as U.lactuca can be effectively utilized for biodiesel production so as to replace fossil fuel usage.