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Open access

Amina S. Yusuf, Ibrahim Sada, Yusuf Hassan, Temitope O. Olomola, Christiana M. Adeyemi and Sunday O. Ajibade

Abstract

The synthesis of five monocarbonyl analogues of curcumin is described. In vitro anti-malarial assay of the compounds was carried out and the effect of the substituents on the aryl ring has been described. The results show that all the five compounds exhibited some reasonable activity against the chloroquine-resistant plasmodium parasite. Molecular docking studies further confirmed the observed biological activity of the compounds.

Open access

Nivrati Jain, Harshita Jain, Ashish Jain, Veerasamy Ravichandran and Prateek Jain

Abstract

We described here the synthesis and biological evaluation of a series of 2, 4, 6-trisubstituted quinazoline derivatives as potential anti-inflammatory, analgesic and antibacterial agents. The synthesized compounds were characterized by FTIR, 1H NMR and mass spectroscopy analysis. We found that the compounds 6b, 6e, 6g, 6h and 6j showed better anti-inflammatory activity than indomethacin. Compounds 6b, 6e, 6h, 6j and 6l were found to exhibit appreciable analgesic activity, and 6b, 6g and 6k showed good antibacterial activity against Gram (+) bacteria: B. subtilis, S. aureus, S. epidermis, and Gram (-) bacteria: E. coli, P. aeruginosa and K. pneumoniae. Compound 6b showed overall better anti-inflammatory, analgesic and antibacterial activity among the synthesized compounds. The results of the present study could be helpful for the designing of effective anti-inflammatory, analgesic and antibacterial agents.

Open access

Paschal Okiroro Iniaghe and Gilbert Umaye Adie

Abstract

In this study, soil contamination by toxic metals released from cathode ray tubes (CRTs) openly discarded within the vicinities of artisans’ workshops in Nigeria was assessed in order to ascertain the metal leaching potential of CRTs, mobility and bioavailability of the leached metals in soil. Furthermore, the ecological geochemistry of the impacted soils was carried out. Seventy soil samples were randomly collected from thirty five locations at depths 0 - 15 cm (top-soil) and 15 - 30 cm (sub-soil), respectively from two selected states each within five geographical regions of Nigeria. Environmentally available lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni) and copper (Cu) were extracted from dried and sieved soil samples using aqua regia solution and were analyzed using flame atomic absorption spectrometry (AAS). Additionally, the metals were also sequentially extracted into five fractions and their concentrations determined using AAS. Concentration of Pb ranged from 0.4 - 6510 mg/kg with all top-soils exceeding the Nigerian NESREA regulatory limit of 164 mg/kg while Cd, Cr, Ni and Cu levels were within their respective regulatory limits. Geoaccumulation index values indicated that approximately 83% of all top-soils represented strong to extreme contamination by Pb while sequential extraction showed that majority of the extracted Pb was in the Fe-Mn oxide, residual and exchangeable forms. The results generally suggest that CRT disposal areas are highly polluted with Pb with significant amounts in bioavailable phases. Thus, waste CRTs are required to be managed in an environmentally sound manner to forestall any probable harm to ecological functioning of such areas.

Open access

Faith Iguodala Akinnibosun and Abigail Ashegbare

Abstract

This study was aimed at isolating and characterizing hydrocarbon-degrading fungi from hydrocarbon-contaminated soil in Ogbe-Ijoh oil creek in Warri, Delta State, Nigeria. Isolation and characterization were carried out using standard methods. Biodegradation assay was carried out over 25 days and monitored using the following parameters; pH, total organic carbon, and total hydrocarbon content. The fungi isolated were: Penicillium sp., Aspergillus niger and Fusarium sp., and these were used for the biodegradation study. Physico-chemical analysis of the crude oil contaminated soil during degradation showed that there was significant decrease in pH during degradation from day 10 - 25 (p ≥ 0.05). This showed the ability of the fungal isolates to utilize crude oil as carbon source, producing acid during its metabolism. The highest pH value during degradation by the fungal isolates was recorded in Fusarium sp. and the lowest was recorded in Aspergillus sp. The fungal isolates were able to reduce the total carbon and hydrocarbon content during degradation. This was probably due to the utilization of the nutrients in the soil sample as energy source. The results from this study indicate the potential of the isolated fungi for hydrocarbon bioremediation activity.

Open access

Faith Iguodala Akinnibosun and Adedayo Michael Oyetayo

Abstract

In this study, cashew apple residue (CAR) was subjected to various treatments (boiling, soaking and fermentation), thereafter, proximate composition and anti-nutrient content were determined. Fermentation significantly (p < 0.05) increased the protein content of the CAR by 56.07% and reduced the carbohydrate content to 42.49%. Moreover, soaking and fermentation significantly reduced phytate content of the CAR from 0.4123% to 0.2504% and 0.1106% respectively; all the treatments significantly reduced the oxalate content while boiling and soaking had a significant reducing effect on the tannin content of the CAR. These suggest that pre-treated cashew apple residue may be used for animal feed formulation.

Open access

Shashidhar N. Adarakatti, Veeresh S. Pattar, Prashant K. Korishettar, Bhagyashri V. Grampurohit, Ravindra G. Kharabe, Akshay B. Kulkarni, Shridhar N. Mathad, Chidanandayya S. Hiremath and Rangappa B. Pujar

Abstract

Li-Ni ferrite has gained great scientific elicit owing to of its unparalleled properties and applications. The copper doped Li-Ni ferrite has been synthesized by sucrose method. The structure was characterized by X-ray diffraction, which has confirmed the formation of single-phase spinel structure. X-ray diffraction and FTIR data reveals the formation of cubic structure phase. Unit cell parameters vary with copper content; overall variation of the unit cell parameters obeys Vegard’s law. The main absorption bands of spinel ferrite have appeared through IR absorption spectra recorded in the range of 300–700 cm−1. The copper concentration dependence of lattice parameters obeys Vegard’s law. DC electrical resistivity of the prepared samples decreases with increasing in the temperature which shows the semiconducting behaviour of all nano ferrites. The most prominent influence copper doping on the electrical properties of Li-Ni ferrites has been reported.

Open access

Ceylan Hepokur, Hesna Nursevin Öztop and Dursun Saraydin

Abstract

In this study, molecular imprinted polymers for highly selective recognition of cholic acid, which is a bile acid, were prepared. Acrylamide, methacrylic acid, methacrylamide were chosen as monomer for the production of molecularly imprinted polymers. Functional monomers were polymerized with various crosslinkers; ethylene glycol dimethacrylate (EGDMA), 1,4-butanediol diacrylate (BUT), trimethylpropane triacrylate (TMT) with target molecule (MIP-EGDMA, MIP-BUT and MIP TMT) and various MIPs were prepared. The cholic acid was removed from MIP with a suitable method. NIP polymers were synthesized without cholic acid (NIPEGDMA, NIP-BUT and NIP-TMT). For the characterization of synthesized polymers FTIR, DSC, TGA, SEM analyses were used. The parameters that affect the adsorption of target species on polymers such as temperature, pH, and concentration were evaluated. The selectivity and reusability studies were also investigated.

It is concluded that MIPs showed better adsorption capacity than NIPs for all solvents for cholic acid. The adsorption sequencing is MIP-TMT > MIP-BUT > MIP EGDMA. The maximum adsorption achieved with ethyl alcohol. The adsorption of cholic acid varies with chancing pH for all produced MIPs and NIPs. It is concluded that the adsorption of cholic acid is not affected by the temperature. The adsorption of cholic acid is followed as L type from Giles adsorption isotherms. The thermodynamic parameters are proved the physical nature of adsorption process. The studies conducted with deoxycholic acid, taurocholic acid that is homolog to cholic acid showed that produced MIPs are highly selective for cholic acid.

Open access

Cong Tien Nguyen, Ha Manh Bui and Duyen Hoang My Nguyen

Abstract

The A new benzothiazepine’s derivative names N-(p-tolyl)-2-(2-(4-phenyl-2,3-dihydrobenzo[b][1,4]thiazepin-2-yl)phenoxy)acetamide was synthesized by reaction of o-aminothiophenol and N-(p-tolyl)-2-(2-(3-oxo-3-phenylprop-1-en-1-yl)phenoxy)acetamide, which was prepared from salicylaldehyde and acetophenone through (E)-3-(2-hydroxyphenyl)-1-phenylprop-2-en-1-one. The structures of the compounds were determined by IR, 1H-NMR, 13C-NMR and HR-MS spectral data.

Open access

Fatemeh Rigi and Hamid Reza Shaterian

Abstract

Silica ammonium acetate (SiO2-NH4OAc) was applied as an inexpensive, practical and heterogeneous catalyst for the preparation of new and known dihydropyrazolo[4',3':5,6]pyrano[2,3-d]pyrimidine-5,7-diones via one-pot four-component reaction of hydrazine hydrate, ethyl acetoacetate aldehydes and barbituric acid/dimethyl barbituric acid under solvent-free conditions. Silica supported ammonium acetate (SiO2-NH4OAc) was prepared according to easy procedure under ambient condition. After completion of the reaction, the catalyst was separated by filtration and reused. So, recycling system, simple work-up, using non-toxic materials, excellent yields and short reaction times makes our research green and convenient for preparation of these classes of organic compounds.