Applied Chemistry

The phytochemical screening, proximate composition, mineral elements and quantitative assay of anti-nutrients of the seeds of Cassia hirsute have been evaluated. The brown seeds have pungent smell and are bitter and unpleasant to taste. The phytochemical screening indicated the presence of alkaloids, tannins, saponins, phenols, sterols, triterpenes, glycosides and carbohydrates; phlobatannins and flavonoids were absent. The proximate composition of the seeds was 8.7% moisture, 7.7% ash, 7.0% fat, 10.5% protein, 13.2% fibre and 52.9% carbohydrate with estimated caloric value of 316.20 kCal/100g sample. The mineral elements determined in the seeds include K, Ca, Na, Fe, Mg and P, heavy metals such as Pb, Cr and Cu were not present. The antinutrient assay revealed that the total tannins, oxalate and phytic acid contents were high but hydrocyanic acid was not detected. The high values of these toxic materials suggest that the seeds are not suitable for consumption as food, but the solvent extract may be suitable as fumigant to dispel insects, rodents and snakes.

The Schiff base chelate of Cu(II) and Ni(II) derived from condensation reaction of salicylaldehyde and 2-aminophenol have been synthesized and investigated by different physicochemical techniques. The resulting complexes were characterized by elemental analysis, molar conductance, FT-IR, melting point or decomposition measurements, solubility in different solvent. The elemental analysis data show the formation of 1:1 metal to ligand ration. The Schiff base act as a tridentate ligand, coordinated through daprotonated phenolic oxygen and azomethine Nitrogen atom. The synthesized chelates were assayed for antibacterial activity against some pathogenic bacteria:Staphylococcus aureus, and Escherichia coli, and the fungi: Aspergillums niger and Candida albican, using dics diffusion method. The synthesized Schiff base complexes exhibit higher antimicrobial activity than the free Schiff base due to the chelation.

Structural characterization methods in Inorganic Chemistry are tools that lead every synthetic chemist to the final destination of synthesis. Therefore, in this article, the various methods of elucidating newly prepared ligands and the corresponding complexes are discussed. The methods, ranging from spectroscopic to non-spectroscopic have been discussed in principle, functions and uses.

Previous studies have shown that the physiochemical properties of urine could change after ingestion of medicinal plants, and may provide significant clinical and diagnostic information. This study examined the urinary profile of healthy subjects who consumed Cymbopogon citratus (C. citratus) infusion. Urine samples were obtained from 105 participants at days 0, 10 and 30 after treatment with infusions prepared from 2, 4 and 8g of C. citratus powder. Biochemical analyses of the urine to determine its chemical constituents were performed using standard procedures. Results obtained on days 10 and 30 were compared with baseline values. UV and UF increased in all groups. Urinary excretion of some electrolytes (Na⁺ and K⁺) and DA increased at day 10 only, whereas others (Ca²⁺ and Cl^-) increased at both days 10 and 30. USG and colour remained unchanged. Urinary creatinine levels significantly increased (p<0.05) in all groups, whereas urinary urea significantly (p<0.05) increased in all groups except the group treated with 8g for 30 days. Urine uric acid and pH decreased in all groups. Urinary protein, glucose, bilirubin and bicarbonate were undetected. Ingestion of C. citratus infusion is associated with some physiochemical changes in urinary composition and could provide significant clinical information on the systemic effects of the plant in humans.

The ligand, 2-methyl-1,3-oxazole-4-carbaldehyde thiosemicarbazone (HL) was synthesized by reacting equimolar amounts of thiosemicarbazide with the corresponding aldehyde. The synthesized ligand was reacted with Ni(II) and Co(II) chlorides in the 2:1 mole ratio of ligand: metal. These led to the isolation of two new complexes, namely [Ni(HL)2]Cl2 (1), [Co(L)2].1.3Cl (2), the ligand and its metal(II) complexes were characterized by elemental analysis, IR, 1H NMR, 13C NMR spectroscopic methods, UV-Vis spectrophotometry and X-ray diffraction. The X-ray structural studies of the ligand and their corresponding metal complexes 1, 2 revealed that: The free ligand exist in the thione form and remain as neutral tridentate with NNS donor atoms in the complex (1) but in the complex (2) the HL acted as uninegative tridentate ligand, beside Presence of uncoordinated chloride ions in the cavities of the crystal lattice of the complex (2). One of these chlorides is hydrogen bonded to a proton of the amine of the ligand. The coordination environment of Ni(II) and Co(II) metal complexes 1, 2, has a distorted octahedral structure. The oxazole N and S atoms in the two complexes are cis to each other whereas the azomethine N atoms are trans coordinated. The ligand and its metal complexes were tested for their in vitro biological activity against seven standard microorganisms: two Gram positive namely Bacillus subtilis and Micrococcus luteus, and one Gram negative bacteria Escherichia coli and four fungi: Saccharomyces cerevisiae (Baker’s yeast), Candida maltosa, Mucor spec., and Aspergillus niger, at a concentration 100µg/ml. The results showed that the ligand HL and its Ni(II) Co(II) complexes appear inhibition activity for Mucor spec. only.

The UV photofragment spectrum of the dication sandwich complex Ca(Benzene)2]2+ had been recorded in the gas phase using a quadrupole ion trap mass spectrometer. From the DFT calculations, the optimised C2 and C2v conformers of Ca(Benzene)2]2+ were confirmed. Methane activation with calcium benzene dication complex ion resulted in the formation of methane calcium benzene dication complex ion [Ca(Benzene)2CH4]2+ and methane calcium benzene mono-cation [Ca(Benzene)CH4]+. The calculated charge on the metal centre was reduced by 40% in the optimised geometry of [Ca(Benzene)2CH4]2+ as compared to the charge of +2 assumed on Ca metal in the PEC calculation. The DFT calculated result reveal that the binding energy of methane to the metal dication complex ion was 13.28% lower compare to the value obtained on the PEC model.

The present study is aimed to analyze the statistical relationship among various water quality parameters and water quality index (WQI). For this, observed results of physico-chemical analysis of 71 ground water samples of study area in pre- and post-monsoon season and calculated water quality index values for each respective sample were taken into consideration. Correlation coefficient between every water quality parameter and WQI values is calculated and for the pairs having highly significant correlation coefficient (0.8<r<1.0) values; regression model is applied and scatter plots are drawn. The systematic correlation and regression study suggested the perfect linear relationship between Fluoride and WQI Values. The analysis provides essential information regarding the dependency of water quality rating on each water quality parameter.

Schiff bases (E)-4-chloro-2-((phenylimino)methyl)phenol, (E)-4-chloro-2-(((2-methoxyphenyl)imino)methyl)phenol, (E)-4-chloro-2-(((4-chlorophenyl)imino)methyl)phenol, (E)-4-chloro-2-(((5-chloro-2-methylphenyl)imino)methyl)phenol were synthesized from 5-chlorosalicylaldehyde and substituted aniline. The synthesized compounds were characterized by elemental analysis, IR, UV, 1H, and 13C NMR. The antibacterial studies revealed that the compounds exhibit broad spectrum antibacterial activity against Escheriochia coli, Klebsiella pneumonia, proteus mirabilis, Pseudomonas aeruginosa and Salmonella typhimurium. The antibacterial activities was affected by the substituent on the aniline part.

The second order reaction rate constant for the reaction of Cinnemaldehyde with aniline have been reported in ethanol in the temperature range 303 to 318 k .The rate of reaction is first order with respect to Cinnemaldehyde and first order with respect to aniline. Increase in temperature increases the rate of reaction. The thermodynamic parameters are used to explain the nature of reaction .Suitable reaction mechanism has been suggested for the formation of the Schiff base.

Insects are among the most diverse types of animals within the arthropod group that are usually collected for food and feed. The vitamin profile of ten insect samples: adult bee, bee brood, winged termite, termite soldier, mopane worm, scarab beetle, snoult beetle, maize weevil, silkworm larva and silkworm pupa were investigated using standard analytical methods. Among the water-soluble vitamins investigated, vitamin B3 (niacin) had the highest concentration in each of the samples with values 4.57-7.33mg/100g whilst vitamin C (9.27e-5-1.34e-4) recorded the lowest concentration. Other water-soluble vitamins (mg/100g) determined were B1: 0.050-0.096, B2: 0.261-0.387, B5: 1.48e-3-4.14e-3, B6: 0.124-0.156 and B9: 6.55e-3-8.58e-3. Vitamin E (1.50-2.48mg/100g) was most concentrated among the fat-soluble vitamins investigated followed by vitamin A (0.021-0.110mg/100g) whilst vitamin K (6.63e-4-1.04e-3mg/100g) had the least concentration. The statistical analysis using Chi-square at ? = 0.05 showed that no significant differences existed among the samples in the parameters determined. This research work has therefore provided more useful and reliable information on the vitamins composition of the analyzed ten insect samples that could enhance their usefulness and applications in Food industry.