Optimization of Lipase Activity from Pseudomonas Fluorescens Using Response Surface Methodology

To ensure optimal lipase activity from Pseudomonas fluorescens, selection of various parameters for an optimized fermentation process is vital. The current study is aimed at the optimization of process parameters of the fermentation based on three basic process parameters during fermentation including pH, fermentation temperature and incubation hours so as to improve lipase activity using response surface methodology (RSM) coupled with central composite design method (CCD). As per the experimental data, correlation between the three investigated parameters with respect to lipase activity of Pseudomonas fluorescens was obtained. The results of analysis of variance (ANOVA) proved that the correlation proposed by quadratic regression was adequate for predicting lipase activity of Pseudomonas fluorescens. It was concluded that the lipase activity was significantly influenced by fermentation parameters. The fermentation temperature of 30 ⁰C, pH value of 8.5 and incubation of 30 hours were found to be optimal for optimal enzyme activity

Isolation and characterisation of polysaccharides from traditionally known Chinese medicinal mushrooms

Medicinal mushrooms are known for their traditional use for the treatment of various diseases including diabetes, cancer and cardiovascular diseases. Mushrooms have been traditionally used for curing numerous life-threatening diseases such as cancer, Tuberculosis, Parkinson’s and Alzheimer. Cancer is one of the leading causes of death worldwide and finding better therapeutics to treat this disease is an urgent need. Literature demonstrates the potential of mushroom polysaccharides for their therapeutic value with significant immunostimulatory and anticancer activities with least side effects. A few polysaccharides from medicinal mushrooms (e.g. Polysaccharide Krestin, Polysaccharopeptide) are already in clinical use to treat cancer. This research therefore aims to isolate polysaccharides with immunomodulatory, prebiotic and anticancer properties from traditionally known medicinal mushrooms Ganoderma lucidum, Cordyceps sinensis and Trametes versicolor. The objectives of this research are to study the biological activities relevant to anticancer therapy and to evaluate the structure- function relationship of mushroom polysaccharides. It is therefore expected that these mushrooms have tremendous potential for the discovery of polysaccharides with immune enhancing, prebiotic and anti-cancer properties and hence chosen for this study. A total of six polysaccharides have been identified in this thesis from two medicinal mushrooms (G. lucidum and C. sinensis). Four of these fractions (GLP-1, GLP-2, GLP-3, CSP-1) have displayed significant radical scavenging activities. These activities correlated well with molecular masses and structural elements. GLP-1 and GLP-3 displayed highly significant immunostimulatory activities with respect to both cytokines and are extremely important candidate for immunotherapeutic applications. CSPs and GLPs have also displayed significant prebiotic activities that are highly significant. Overall, the results presented in this thesis strongly suggest immune enhancing, prebiotic and direct anticancer activities of polysaccharides from G. lucidum and C. sinensis (GLPs and CSPs). It is therefore concluded that these polysaccharides form potential candidates for combination “immuno-chemotherapy”. It is therefore suggested that, pre-treatment of cancer patients with immunostimulatory and prebiotic mushroom polysaccharides identified in this research to activate cancer microenvironment and to improve gut microbiota, followed by therapy with suitable immune checkpoint inhibitors is expected to produce enhanced outcomes for cancer patients. It is in this context that the immune enhancing and prebiotic mushroom polysaccharides discovered in this research have great potential in the treatment of cancer

Optimal nutritional modes combination of Chromochloris zofingiensis in multiple cultivation process for biomass and astaxanthin productivity

創価大学博士（工学）Chromochloris zofingiensis is an emerging alternative for the commercial production of astaxanthin, to Haematococcus pluvialis, due to its high productivity and ability to grow in multiple nutritional modes namely, autotrophic, mixotrophic and heterotrophic. The cultivation of microalgae in multiple culture steps (stock, preculture, and biomass production phase) in different nutritional modes can contribute to the enhancement of cell biomass and has hardly been performed. Moreover, it’s effect on cell growth and biomass productivity is still unknown. Therefore, in this study, we firstly observed the cell growth in different nutritional modes in preculture phase (Chapter II, Study 1). Later, the effect of preculture on the biomass production via combination of nutritional modes for determining the optimum conditions (stock, preculture and biomass production phase) was evaluated (Chapter III, Study 2). As a result, heterotrophically precultured cells showed higher biomass productivities than with auto- and mixotrophically precultured cells in autotrophic and mixotrophic in biomass production phase. The increase in productivity was due to the stored cellular materials such as lipids, starch and nuclei in heterotrophically precultured cells (Study 2). In the three-phase culture, a highest biomass productivity was obtained in mixotrophic condition (Chapter IV). This study suggested that the optimum combinations of nutritional modes for higher biomass and astaxanthin productivity are autotrophic for stock (to maintain the following heterotrophic growth), heterotrophic for preculture (to store growth-promoting factors), mixotrophic for biomass production phase (to achieve high productivity), and autotrophic (for astaxanthin induction), respectively.doctoral thesi

Fumaric acid production by Rhizopus oryzae and its facilitated extraction via organic liquid membrane

Microbial fermentations are efficient alternatives to different manufacturing practices being followed for industrially important compounds like organic acids, food and pharmaceutically active products. However, the attractions offered by microbial processes are overshadowed by the costs associated with downstream processing involved in the recovery of pure products from such systems. Reduction of the cost in terms of financial and energy related inputs have been the goal of recent ongoing research in the field of bio-processing. This study has been focused towards development of an efficient method for simultaneous extraction of products from microbial fermentation. Through the study, the domain of liquid membranes and the possibilities of energy efficient extraction of microbial products from ongoing processes have been investigated. Liquid membrane system involves a liquid which is immiscible with the source and receiving solutions serves as a semi permeable barrier between these two liquid phases. The study uses a fumaric acid produced through fermentation of Rhizopus oryzae on Potato Dextrose Broth (PDB) under aerobic conditions as a model sample for extraction analysis. The culture media, that is presumably rich in fumaric acid and some other acidic products, has been subjected to extraction through liquid membrane based process. The reduction in concentration of sample used as source is measured titrimetrically. Thin layered chromatography has been deployed at certain instances for qualitative verification of the concentrations. The set up consisted of a modified layered 'liquid membrane’ setup for a ‘fumaric acid’ source, with toluene as organic membrane and sodium hydroxide as strip phase. The liquid membrane contained a carrier for assisted transfer and was agitated. Maximum extraction takes place during the first 20 to 30 min of the run as fumaric acid concentration falls to almost 40% of its initial concentration.Keywords: Fumaric acid, carrier, trioctylamine (TOA), liquid membrane, facilitated extractionAfrican Journal of Biotechnology, Vol. 13(10), pp. 1182-1187, 5 March, 201

Trends in EEG signal feature extraction applications

This paper will focus on electroencephalogram (EEG) signal analysis with an emphasis on common feature extraction techniques mentioned in the research literature, as well as a variety of applications that this can be applied to. In this review, we cover single and multi-dimensional EEG signal processing and feature extraction techniques in the time domain, frequency domain, decomposition domain, time-frequency domain, and spatial domain. We also provide pseudocode for the methods discussed so that they can be replicated by practitioners and researchers in their specific areas of biomedical work. Furthermore, we discuss artificial intelligence applications such as assistive technology, neurological disease classification, brain-computer interface systems, as well as their machine learning integration counterparts, to complete the overall pipeline design for EEG signal analysis. Finally, we discuss future work that can be innovated in the feature extraction domain for EEG signal analysis

Use of nanomaterials in the pretreatment of water samples for environmental analysis

The challenge of providing clean drinking water is of enormous relevance in today’s human civilization, being essential for human consumption, but also for agriculture, livestock and several industrial applications. In addition to remediation strategies, the accurate monitoring of pollutants in water sup-plies, which most of the times are present at low concentrations, is a critical challenge. The usual low concentration of target analytes, the presence of in-terferents and the incompatibility of the sample matrix with instrumental techniques and detectors are the main reasons that renders sample preparation a relevant part of environmental monitoring strategies. The discovery and ap-plication of new nanomaterials allowed improvements on the pretreatment of water samples, with benefits in terms of speed, reliability and sensitivity in analysis. In this chapter, the use of nanomaterials in solid-phase extraction (SPE) protocols for water samples pretreatment for environmental monitoring is addressed. The most used nanomaterials, including metallic nanoparticles, metal organic frameworks, molecularly imprinted polymers, carbon-based nanomaterials, silica-based nanoparticles and nanocomposites are described, and their applications and advantages overviewed. Main gaps are identified and new directions on the field are suggested.publishe

Sorption and Preconcentration of Lead on Silica Nanoparticles Modified with Resacetophenone

The silica-resacetophenone (SiO2-RATP) nanoparticles were used as a new sorbent for extraction of trace amounts of Pb(II) by batch technique. Conditions of the analysis such as preconcentration factor, effect of pH, sample volume, shaking time, elution conditions and effects of interfering ions for the recovery of analyte were investigated. The adsorption capacity of nanometer SiO2-RATP was found to be 167.24 µ mol/g at optimum pH and the detection limit (3σ) was 0.58 µg/L. The adsorption equilibrium of Pb(II) on nanometer SiO2-RATP was achieved in 20 min. Adsorbed Pb(II) was easily eluted with 5 mL of 0.5 M hydrochloric acid. The maximum preconcentration factor was 60. The method was applied for the determination of trace amounts of Pb(II) in various natural water rivers