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Abstract

This work involved the production and thermal characterization of biomass briquettes produced by blending a major agricultural waste with coal dust. In the work, nine different compositions of coal dust/groundnut husk briquettes were produced using starch as the binder while Ca(OH2) was incorporated as the de-sulphurizing agent. The ash content, volatile matter, fixed carbon, moisture content, compressive strength, ignition time, calorific value, water boiling test and burning rate were carried out to determine the physical, mechanical and thermal properties of the briquettes produced. The results showed that moisture content values are in the range 2.43 - 6.44%, for compressive strength 7.72 - 10.85 N/mm3, for ash content 24.18 - 29.15 %, for calorific value 21714.17 - 25027.18 kJ/kg, for fixed carbon 16.77-53.22 %, for ignition time 22.23-45.20 s, for water boiling test 1.50-4.99 min and burning rate 16.10-28.32 g/min. These are appreciable values for the thermal properties of the bio-briquettes. Therefore, the agro-wastes briquettes are beneficial for heating purposes rather than open incineration of the wastes.

Abstract

New organotin (IV) complexes with NaL1 (sodium salt of 2-[[4-(3-methoxy-propoxy) -3-methylpyridin-2-yl]methylsulfinyl]benzimidazol-1-ide) and NaL2s (sodium salt of 3- aminomethyl-5-methylhexanoic acid) were synthesized by the reaction of diorganotin (IV) and triorganotin (IV) salt (Bu3SnCl, Ph3SnCl, Bu2SnCl2, Me2SnCl2) using the solvent (dry toluene) by constant stirring and refluxing. All the organotin (IV) complexes were characterized by different diagnostic techniques such as FT-IR (Infra-red) and UV-visible spectroscopy. The results exhibited that ligand NaL1 (sodium salt) is attached to tin metal by a nitrogen atom of benzimidazole ring and the oxygen atom of the sulfonyl group. While ligand NaL2 (sodium salt) coordinate with tin(IV) moiety through oxygen atom of the carboxylate group. The newly synthesized complexes 1 & 2 of ligand NaL1 (sodium salt) showed trigonal bipyramidal geometry while complexes 3 & 4 octahedral geometry around tin(IV) centre. The organotin(IV) complexes 5-7 of ligand NaL2 (sodium salt) have the tetrahedral geometry around tin(IV) centre. The synthesized complexes (1-7) were tested for antifungal and antibacterial microbial activities. All the complexes showed significant antibacterial and anti-fungal activities against tested bacterial and fungal strains.

Abstract

Studies on the adsorption of Pb(II) on plantain peels biochar (PPB) was conducted. The carbonized and activated, biochar was characterized using Braunauer-Emmett-Teller (BET) surface area and x-ray diffraction crystallography (XRD). BET analysis of the PPB indicated that the pore size (cc/g) and pore surface area (m2/g) was 8.79 and 16.69 respectively. Result of the XRD evaluated through Debye-Scherrer equation, showed a nanostructure with crystallite size of 14.56 nm. Effects of initial metal ion concentration, pH, and contact time were studied in a batch reaction process. Results showed that the adsorption of lead from aqueous solution increased with an increase in pH and initial concentration. Equilibrium modeling studies suggested that the data fitted mainly to the Langmuir isotherm. Adsorption kinetic data tested using various kinetic models fitted the Weber and Morris intraparticle diffusion model implicating pore diffusion as the main rate limiting step. The sorption studies indicated the potential of plantain peel biochar as an effective, efficient and low cost adsorbent for remediating lead (II) ions contaminated environment.

Abstract

Momordica cochinchinensis, or Gac fruit belongs to Cucurbitaceae family. Although this species is considered to be native in Southeast Asia especially in Vietnam, Thailand and Laos, it is still contemplated as a rare and new fruit species in Malaysia. Availability of this species is very limited in Malaysia hence, the raw material for researches is also in short supply. Currently, Gac fruit is utilized as traditional food, health supplements, food colouring and juices. Gac fruit was discovered to have high value pharmaceutically and economically as it had been recognized as a rich source of bioactive compounds. On that account, this study aimed to generate preliminary data on the morphological characterisation and phytochemical composition which focused on β-carotene and lycopene content of Gac fruit aril. This data could be useful for further researches particularly on breeding improvement of Gac fruit. The morphological characterisation was mainly based on both vegetative and reproductive parts of the plant. Both β-carotene and lycopene content of aril was analysed and estimated using UV-Vis Spectroscopy technique. The aril was extracted using mixed solvent of n-hexane 95%, ethanol 99.9% and acetone 99% with ratio of 2:1:1 v/v/v. Furthermore, morphological data of root, stem, leaf, flower, fruit and seeds were also successfully recorded. Besides that, the β-carotene and lycopene content obtained were 0.117 ± 0.011 mg/g FW and 0.021 ± 0.002 mg/g FW, respectively. Discrepancy in the results might be due to numerous factors like collection sites, level of maturity at harvest, storage and processing conditions, analysis techniques and type of solvent extractors used that might have affected the quality and contents of the carotenoid. Several suggestions for extension of this study had been propounded so that the benefits of this species could be exploited in the best possible ways.

Abstract

The ingestion of aluminum from food containers such as cookware, cans, utensils and wrappings and its subsequent release into the environment is a growing public health concern. Aluminum is widely used in manufacturing cookware due to its malleability, high heat conductivity, light weight, durability, availability and affordability. This paper therefore gives a review of most relevant literatures on the benefits and risks of the various types of aluminum cookware in use, the composition and the public health effects of aluminum ingestion. Studies that reported the leaching of aluminum from cookware into food and environmental effects of aluminum leaching were also reviewed. In the developing countries, aluminum cookwares are produced from scrap metals and has been reported to leach harmful substances including heavy metals such as: nickel, arsenic, copper, cadmium, lead, and aluminum into cooked food. Several factors have been reported to increase the rate of leaching of metals from aluminum cookwares. Exposure to metals from aluminum cookware and the public health effects have not been well studied, hence, our recommendation for more studies to elucidate the health effect of this practice. This review also presents measures that can limit exposure to the risks that may arise from the use of aluminum cookware.

Abstract

The volume of pharmaceuticals discharged into the environment increases daily as a consequence of human life. In the present study, the seasonal variation of ibuprofen in sediment, biota, water, and their exposure risk were investigated in River Owena and Ogbese, Nigeria. The high-performance liquid chromatography coupled to a mass spectrometer (HPLC-MS/MS) was used to analyze the samples after clean up and pre-concentration by solid-phase extraction. The mean concentration of IBU in the samples spanned a range of 1.75 - 2.75 μg/g in sediment, 0.01 – 15.00 μg/g in fish, and 0.00002 – 0.005 μg/ml in water. The measurement of IBU in the sediment and water was significantly elevated in the dry season than the wet season, whereas the opposite was the case in biota. There was a significant interaction between season, media, and rivers with respect to IBU occurrence in the sampled rivers. The calculated bio-water accumulation factor (BWAF) was as high as 750,000 μg/g in fish, proving IBU is extremely bio-accumulative. The ecotoxicological risk assessment for average and worst possible outcome showed that the risk quotient (RQ) for IBU present in the water was sufficient to cause toxicity to fish in both freshwater bodies. The potential bioavailability of IBU to aquatic fauna for prolonged periods spanning several months can result in its circling back into the food web afterward. The baseline info provided by this study in these freshwaters may provide valuable information for the implementation of safety limits for the management of IBU influx into the environment.

Abstract

The allelopathic potential of essential oil extracts from Artemisia herba-alba Asso. was assessed on seed germination of nine weeds and two wheat varieties. The samples were collected from El-Rasfa région (Sétif, Algeria). The essential oil was extracted using hydrodistillation of aerial part and characterized using gaz chromatography coupled with mass spectroscopy. The bioassays with organic solvent (ethanol) were tested using four different concentrations (0.2, 0.4, 0.6 and 0.8 µl/ml of oil/ethanol) on seed and seedling growth of the nine weeds and two wheat varieties. The yield obtained is 1.19%, and 36 compound had been identified. The main components are: camphor (28.58%), cis-thujone (22.03%), eucalyptol (11.65%) and trans-thujone (7.03%). The results of bioassays show that essential oil extracts has a significant effect on seed germination and seedling growth of the major weed tested and two wheat varieties. In conclusion, this study shows that the essential oil tested has an interesting allelopathic potential.

Abstract

The experiment was conducted at the level of a pilot farm located in eastern Algeria under a humid bioclimatic stage, during two successive crop years. The study focused on a F1 generation of barley (Hordeum vulgare L.) consisting of twelve hybrids from a complete diallel cross between the two locals varieties (Saida and Tichedrett) and two other introduced varieties (Nadawa and Fouara). The aim was to determine the value of parental genotypes as genitors and to analyze their descendants, while evaluating the phenotypic variability of ten quantitative variables. Analysis of the variance revealed a significant difference for the whole of parameters studied in the parents as in their descendants. Additive and non-additive effects are involved in the genetic control of the analyzed variables. The Hayman model (1954) seems acceptable for five variables on ten variables studied for which additive effects are more important than dominance effects. The analysis of the heterosis effect was significant for the characters tested. For the productivity of the plant, eight hybrids on twelve have expressed a positive heterosis compared to the mid- parent, six combinations on twelve have registered a positive heterosis compared to the over-batter parent and compared to the best variety with an overall heterosis of 17.53%.

Abstract

This study was conducted to evaluate anti-acetylcholinesterase and insecticidal and antifungal activities of the endophytic fungus Trichoderma sp, isolated from Ricinus communis L. leaves, against Locusta migratoria L. and Botrytis cinerea Pers.: Fr.. To evaluate the insecticidal and antifungal activities, different concentrations of the fungal extract were applied against L. migratoria (0.2, 0.3, 0.4 g/l) and against B. cinerea (1, 2, 3 g/l). It was found that the mortality of the targeted insects was positively proportional to fungal extract concentration and time after exposure (24, 48, 72 hours). The concentration 0.4 g/l appeared to be the most effective after 72 hours with mortality rate of 56.52%. Regarding antifungal activity, the concentration 3 g/l was the most effective against B. cinerea after 7 days, with an inhibition rate of 92.06% (excellent antifungal activity). Moreover, it was found that at 4 ug/ml the fungal extract had a maximum inhibitory capacity of Ache of 80% for acetylcholenesterase. Preliminary phytochemical analyses revealed the presence of alkaloids, flavonoids, phenols and saponins. In addition the colony of this endophytic fungus produced chitinases and proteases, which explained its important antifungal and insecticidal activities.

Abstract

Certain phenolics have been recognized to possessing antibacterial and antifungal activities and high levels of flavonoids and tannins have been reported in several varieties of Sorghum bicolor (L.) Moench. Antimicrobial activity and phenolics contents were investigated in five Algerian sorghum seeds. AS20 sorghum extract showed the highest levels of: total phenolics (3214.46±263.64 mg/100 g), flavonoids (32.03±1.64 mg/100 g) and tannins (615.35±6.10 mg/g) contents; however, comparable flavonoids content was recorded in I27 extract. FZ40 and AS12 flavonoids contents were comparable. Screening for antimicrobial activity, carried out by the disc’s diffusion method revealed an antimicrobial potential of sorghum crude extracts against Gram-positive and Gram-negative bacteria and candida albicans yeast. Minimal inhibition concentration determined by microdilution method varied between 0.2 and 2 mg/ml. the lowest value was recorded with F11 and FZ40 extract against Streptococcus pneumoniae and F11 against Escherichia coli. Bacillus subtilis, Staphylococcus aureus ATTCC6538 and MRSA strains showed sensitivity to all extracts. The results show these sorghums as a potential source of natural anti-streptococcal, anti-staphylococcal and anti-candida substances.