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Abstract

Zinc phosphodiesterase (ZiPD) participates in the maturation of tRNA precursors. The roles of metal ions in promoting phosphoryl transfer reaction on zinc phosphodiesterase (ZiPD) activity have not been fully characterized. Therefore, this study investigated the effects of some metal ions on phosphodiesterase activity of Escherichia coli ZiPD as well as the binding site and binding affinity of the metal ions. ZiPD activity was measured by monitoring the rate of hydrolysis of bis-para-nitrophenyl phosphate (bis-pNPP) in the presence of some selected divalent metal ions (Mn2+, Co2+, Mg2+ and Zn2+). The results obtained revealed that Mn2+ at 1 mM activated ZiPD activity by 4-fold with binding affinity score of 1.795. Co2+ at 0.5 mM activated ZiPD activity by 2-fold with binding affinity score of 1.773. Mg2+ at 0.5 mM enhanced the binding affinity of ZiPD for bis-pNPP but did not increase the turnover rate of ZiPD. Zn2+ at 1.5 mM activated ZiPD activity by 2-fold via increased affinity of ZiPD for bis-pNPP. In conclusion, the findings from this study showed that Mn2+ and Zn2+ are the most effective stimulatory ions of ZiPD for bis-pNPP while Zn2+ exerted the highest binding affinity of ZiPD for bis-pNPP.

Abstract

Christia vespertilionis (butterfly wing plant) is an ornamental plant originated from South East Asia with reported usage in traditional medicine practice and potential as an anticancer and antitumor. This research aims to estimate the genome size of C. vespertilionis via flow cytometry (FCM) method. The research was conducted with the optimisation of nuclear suspension preparation followed by the genome size estimation. Two chopping techniques [manual chopping (MC) and BDTM Medimachine (MM)] and two lysis buffers (Otto and LBO1) were tested. Otto buffer with manual chopping was found to be the most suitable method, generated fine DNA peak with minimum debris background, and coefficient of variation (CV) value less than 3%. Five replicates of the FCM analysis were made for the genome size determination. The estimated genome size of C. vespertilionis was found to be 3.22 pg by using Glycine max cv. Polanka (2C=2.5pg) as an external reference standard. Further comparison with other Christia species was not possible due to the lack of data on genome size. The genome size data of C. vespertilionis can be useful for future morphology and genetics studies of Christia species.

Abstract

Fall armyworm (Spodoptera frugiperda, J.E. Smith) is a pest with devasting effects on maize. A laboratory biassay was conducted to analyse the phytochemicals and determine the efficacy of M. spicata and R. officinalis extracts on FAW. Treatments were laid out in a Completely Randomized Design (CRD) with 3 replications. The factors included solvent [Methanol (Me), dichloromethane (DCM), distilled water (Di)] and the plant species (M. spicata and R. officinalis). Coragen SC 200 (Co) and Distilled water (Di) were the positive and negative controls, respectively. FAW rearing, plant extract preparation and phytochemical screening were done using standard procedure. Data collection and analysis was done using standard procedures. The extract yield was highest for R. officinalis regardless of the solvent used. Me-R. officinalis and Di-M. spicata extracts yielded the highest. Saponins, glycosides, alkaloid, flavonoids and tannins. Flavonoid contents were 7.9036 mg/mL and 6.0073 ± 0.6117 mg/mL in methanolic extract of M. spicata and R. officinalis, respectively. M. spicatha and R. officinalis extracts caused 100% mortality to 3rd instar larvae. Based on the findings, both M. spicata and R. officinalis have several secondary metabolites that confer insecticidal activity of the plants against FAW, hence should be evaluated under field conditions.

Abstract

The aim of this study was to evaluate the polycyclic aromatic hydrocarbons load in soils of Ogale community, Rivers State, Nigeria and as well delineate the lateral and vertical extensions of the soils and groundwater. Geo-electric characterization of the soils and groundwater, using Electrical Resistivity methods (vertical electrical sounding, VES by Abem Terrameter and Gas chromatograph - Flame Ionization Detector (GC-FID) for finger-print was employed. The interpreted VES results revealed four geo-electric subsurface layers. The first layer which has a resistivity value of 60Ωm and a thickness of 2.0M was interpreted as top soil. Underlying the first layer is the second layer which had a resistivity value of 122Ωm with a thickness of 3m, interpreted as lateritic sand. The third layer had a resistivity value of 750Ωm and a thickness of 9.0m, and is interpreted as coarse sand. The fourth layer which had a resistivity value of 1255Ωm and a thickness of 49m is interpreted as very coarse sand. Borehole one was used as control and it is 1.85km away from the Resistivity sampling points. The results revealed that the presence of C10-C40 hydrocarbon which indicates un-weathered to fresh hydrocarbon in parts of the study area and heavy metals were below detection limits. The vulnerability of the aquifer to hydrocarbon contamination was due to high permeability, unconsolidated coarse grained and poorly sorted sands, of the vadose zone as well as shallowness of the aquifer. It is recommended that boreholes in the study area should be of deeper depths, and well constructed to avoid contaminated water from the polluted zone entering the borehole through the annulus.

Abstract

This study aims to synthesize hybrid compounds “via” the coupling of sulphonamide and benzothiazole into one structure that may have improved antibacterial property. The N-(biphenyl-4-yl) thiourea (1) used for the synthesis of the targeted sulphonamides was obtained by reacting diphenylamine and ammonium thiocyanate at room temperature. Cyclization of N-(biphenyl-4-yl)thiourea gave 2-amino-6-phenylbenzothiazole (2) which reacted with benzenesulphonyl chloride and para-toulene sulphonyl chloride to give the targeted sulphonamides (3a & 3b). The synthesized compounds were characterised using melting point, infra-red spectroscopy, nuclear magnetic resonance and elemental analysis. Anti-bacterial screening of the synthesised compounds indicated that all the compounds showed anti-bacterial properties, except 2-amino-6-phenylbenzothiazole that did not show any activity on Escherichia coli.

Abstract

In an effort at developing new filters and bio-packaging materials with antibacterial properties, nanocomposite fluorescence films of cellulose acetate reinforced with cellulose nanoparticles, methylcellulose nanoparticles, propylcellulose nanoparticles, toluene diisocyanate modified cellulose and cellulose acetate nanoparticles were prepared and characterized. The effects of the nanoparticles on the mechanical, crystallinity and morphology of the nanocomposite films was studied. The sensitivity of bacteria against the new nanocomposite films was experimented. Scanning electron microscopy showed the films to be well dispersed. Modulus increase was directly proportional to nanoparticle loading. Samples with maximum compatibility were cellulose nanoparticles (CNPs) loading of 40% with modulus of 113.3Mpa and toluene diisocyanate modified cellulose nanoparticles (TDI-CNPs) at 20% loading had 146.0Mpa. Others include cellulose acetate nanoparticles (CANPs) at 30% loading with 73.0Mpa; methylcellulose acetate nanoparticles (MCNPs) with 5% loading had a modulus of 87.3Mpa and pure cellulose acetate had 45.0Mpa. The films were applied as filters for the removal of cells of Bacillus; Enterococcus and Micrococcus sp. from the crude bacteriocin, with recoverability of 95.9% based on the bacteriocin produced. The films showed limited antibacterial properties against clinical Pseudomonas sp 1, Pseudomonas sp 2 and Proteus sp. It is concluded that the films showed limited antibacterial properties hence it has antibacterial potentials and capabilities.

Abstract

Bangladesh produces a large amount of corn, pumpkin and carrots every year. To meet its huge energy demand and to lessen dependence on traditional fossil fuel these products are cost effective, renewable and abundant source for bioethanol production. The research was aimed to evaluate Bangladeshi corn, rotten carrot and pumpkin for bioethanol production. About 100 g of substrates was mixed with 300 ml distilled water and blended and sterilized. All the experiment was conducted with a temperature of 35oC, pH 6.0 and 20% sugar concentration. For fermentation, 200 ml yeast (Saccharomyces cerevisiae CCD) was added to make the total volume 500 ml. Addition of small amount of 1750 unit α-amylase enzyme to the substrate solution was found to enhance the fermentation process quicker. After 6- days of incubation, corn produced 63.00 ml of ethanol with 13.33 % (v/v) purity. Bioethanol production capacity of two different local varieties of pumpkin (red and black color) was assessed. Red pumpkin (Cucurbita maxima L.) produces 53 ml of ethanol with purity 6 %v/v and black color pumpkin produces 40 ml of yield with a low purity 4 %v/v. Carrot (Daucus carota L.) produces 73.67 ml of ethanol with 12.66 % (v/v) purity.

Abstract

World health organization (WHO) data shows that air pollution kills an estimated seven million people worldwide every year. A nanofiber based biodegradable facemask can keep breath from smoke and other particles suspended in the air. In this study, we propose branched polymeric nanofibers as a biodegradable material for air filters and facemasks. Fibers have been elecrospun using double bubble electrospinning technique. Biodegradable polymers, PVA and PVP were used in our experiment. Two tubes, each filled with one of the polymers, were supplied with air from the bottom to form bubbles of polymer solutions. DC 35-40 kV was used to deposit the fibers on an aluminum foil. Results show that the combination of polymers under specific conditions produced branched fibers with average nanofibers diameter of 495nm. FT-IR results indicate the new trends in the graph of composite nanofibers.

Abstract

The opening of mitochondrial permeability transition (mPT) pore is a well recognized important event in the execution of mitochondrial-mediated apoptosis. Some bioactive compounds induce apoptosis in tumour cells via the induction of mPT pore opening. This study therefore investigated the effect of 3-Para-fluorobenzoyl-propionic acid (3PFBPA), a metabolite of haloperidol on mPT pore, mitochondrial ATPase activity (mATPase), mitochondrial lipid peroxidation (mLPO) and cytochrome c release (CCR). Thirty-two male Wistar rats, were acclimatized for 14 days in clean cages. After 30 days of treatment, they were sacrificed and the liver mitochondria isolated using differential centrifugation. The mPT pore, mATPase, mLPO and CCR were determined by standard methods using a spectrophotometer. The mPT pore opening was induced by 3PFBPA by 1.4, 3.6, 5.6, 6.6 and 7.4 folds, when compared with the control. Also, there was release of cytochrome c and enhancement of mATPase activity by 3PFBPA. The results also show that 3PFBPA reduced lipid peroxidation. However, oral administration of 3PFBPA at 50, 100 and 200 mg/kg did not have any effect on mPT pore opening and mATPase activity when compared with the control but there was inhibition of mLPO. These findings suggested the pharmacological potential of 3PFBPA against the pathological processes related to insufficient apoptosis (based on the in vitro data) and oxidative stress due to its anti-lipidperoxidative effect.

Abstract

In the present era of continually increasing energy demand, Europe faces many challenges, such as high and unstable energy prices, growing global energy demand, increasing threat of climate change, sluggish progress within energy efficiency and issues related to increasing demand for the use of renewable energy sources. It is desirable to seek opportunities to use energy consumed most reasonably, thus ensuring continuous improvement of energy efficiency in the industry. The scope of the research includes reviewing studies in this matter and analysing the most beneficial solutions for the plant. The work aims to assess possible undertakings to modernise the energy management of an industrial plant on the example of Bulten Poland S.A. rationally and profitably for the plant. The work contains an analysis of the profitability of the potentially most beneficial solutions in terms of improving the energy efficiency of the plant. Mentioned in the article solutions, aiming increasing energy efficiency, helped become the plant independent within heating up facilities. Total heat recovery potential in amount of 18 965 GJ is motivation for further activities. This is a great opportunity to reduce significantly carbon footprint (replacing lightening into LED technology reduced CO2 by 206.3 Mg/year) and be more competitive on the market by reducing costs of product.