International Research Journal of Pure and Applied Chemistry
EISSN : 2231-3443
Published by: Sciencedomain International (10.9734)
Total articles ≅ 809
Latest articles in this journal
Published: 30 September 2022
International Research Journal of Pure and Applied Chemistry pp 23-32; https://doi.org/10.9734/irjpac/2022/v23i5788
Aims: The aims of the study were to analyse the polyphenols of Pulicaria dysenterica (L.) Bernh. methanolic extracts from aerial and underground parts, assessment of antioxidant activity and to evaluate their cytotoxicity on HeLa cells of cervical cancer. Methodology: The total phenolic content (TPC) of extracts was determined by the Folin-Ciocalteu spectrophotometric method. The qualitative and quantitative analysis of individual polyphenolic compounds were performed by the reverse phase HPLC method. The antioxidant capacity was evaluated by both, 2,2-diphenyl1-picrylhydrazyl radical and FRAP assay, while cytotoxicity of the extracts was assessed by MTT assay. Results: TPC of the samples were 127.62±2.22 and 244.12±8.84 mg gallic acid equivalent/g extract. In the extracts chlorogenic acid in amount of 10.06±0.96 and 11.32±0.28 mg/g, flavonoid rutin in amount of 5.68±0.13 mg/g and three caffeic acid derivatives were recorded. Extract from underground parts achieved better antioxidant activity with IC50 value 55.36±0.75 µg/mL and FRAP value 2411.12±37.22 µmol Fe2+g-1 compared to the one from aerial parts. Extract from aerial parts achieved better cytotoxic activity with 50% inhibition of viability (IC50) at concentration of 0.389±0.07 mg/mL, against HeLa cells, compared to the extract from underground parts. Conclusion: Analyzed Pulicaria dysenterica extracts contained phenolic acids and flavonoids. The extracts showed good antioxidant activity and cytotoxic properties against HeLa cells in vitro.
Published: 15 September 2022
International Research Journal of Pure and Applied Chemistry pp 9-22; https://doi.org/10.9734/irjpac/2022/v23i530474
Biomass systems are based on a wide range of feedstock, like food and agricultural waste. The quest for bio-adsorbents that are environmentally benign is the rationale for this study. Thus, the research is aimed at the isolation, physicochemical, and BET analysis of cellulose obtained from Pentaclethra macrophylla Benth Pod (PMBP) biomass waste. The powdered PMBP was dewaxed with toluene and ethanol (2:1) and, thereafter, treated with aqueous sodium hypochlorite (7.5% at 70oC) and sodium hydroxide (17.5%w/v at 80oC) to obtain isolated cellulose. Proximate, ultimate, and chemical composition analysis reveals the presence of cellulose (42.7%), hemicelluloses (7.8%), lignin (38.5%), silicon (40.72%), aluminium (17.10%) and elements. The FTIR and Raman spectroscopic analysis revealed some of the functional groups associated with isolated cellulose and raw PMBP. The presence of hemicelluloses and lignin in the isolated cellulose implies that the isolation process did not remove all the impurities. The BET analysis reveals a better specific surface area, pore volume, and average pore diameter or size of the isolated cellulose, and could serve as a better adsorbent than the raw. As a result of the increased surface area and high percentage of isolated cellulose in PMBP, it can be used as a sustainable energy source as well as for the environmental remediation of heavy metals.
Published: 31 August 2022
International Research Journal of Pure and Applied Chemistry pp 1-8; https://doi.org/10.9734/irjpac/2022/v23i530473
The Schiff base derived from 2-hydroxy-1-napthaldehyde and 4-aminobenzonitrile and its corresponding Co(II), Ni(II) and Cu(II) complexes were synthesized and characterized by means of FT-IR spectroscopy, thermal analysis, powder x-ray analysis (PXRD), conductivity measurement, magnetic susceptibility and elemental analysis. The mononuclear complexes have been obtained by liquid-assisted mechanochemical method. The Schiff base was synthesized in high yield > 90% with negligible waste. FT-IR study indicates a strong band in the spectra of the Schiff base at 1577 cm-1 assigned to azomethine v(C=N) stretching vibration which shifted to new frequency regions in the spectra of complexes indicating the formation of the anticipated complexes. The Schiff base melted at 197oC while decomposition temperatures of the complexes were in the range of 265 - 300oC, signifying good thermal stability. Molar conductance values were in the range of 4.39 - 1349 Ω-1cm2mol-1, indicating non electrolytic nature of the synthesized complexes. Magnetic susceptibility measurement showed that Co(II), Ni(II) and Cu(II) complexes are paramagnetic and exhibit magnetic moment in the range of 1.50 - 3.19 BM, the values correspond to the tetrahedral geometry. The relative percentage of the constituent elements (C, H, N) obtained from CHN analysis and calculated values using the proposed structures are similar and are in good agreement. The Schiff base and metal complexes were evaluated as agent for inhibiting growth of pathogenic bacteria using disc diffusion method. The results indicated that metal complexes are more active compared to Schiff base ligand against the test organisms.
Published: 22 August 2022
International Research Journal of Pure and Applied Chemistry pp 48-66; https://doi.org/10.9734/irjpac/2022/v23i430472
Water resource contamination is a major concern in several regions, especially in the Niger Delta, in which the oil exploration activities pose serious risks to human health, water resource and the environment. This present study evaluates the properties of surface water in Nembe Creek. Surface water samples were collected from three (3) control stations and twenty-four (24) sampling stations around the creek during the wet and dry seasons. The samples were subjected to analysis following the standard operating procedures of ASTM and APHA analytical methods. The relationship between the parameters and variations of surface water quality of Nembe creek were determined by using descriptive statistics, Analysis of variance (ANOVA) and Pearson correlation analysis. The results indicated pH had a mean value of 6.67± 0.33 (wet season) and 7.21 ± 0.3 (dry season), Electrical Conductivity ranged 200 – 3950 µS/cm (wet season) and 17900 – 25800 µS/cm (dry season), DO ranged between 4.3 – 5.8 (wet season) and 3.9 – 5.6 (dry season), Nitrate had values of 0.007- 0.068 mg/L (wet season) and 0 – 0.007 mg/L (dry season), Sulphate values range 130.58- 158.76 mg/L (wet season) and 215.12 – 657.35 mg/L (dry season). Iron range 3.23 – 5.6 mg/L (wet season) and 0.26 – 7.87 mg/L (dry season), Zinc ranged 0.02 – 0.47 mg/L (wet season) and 0.13 – 2.22 mg/L (dry season). Across all sampling stations and control areas during the wet season, the values for Total Petroleum Hydrocarbon (TPH), total hydrocarbon Content (THC) and Petroleum Aromatic Hydrocarbon (PAH) were below the detection limit; however, the values varied during the dry season. The Pearson Correlation matrix revealed positive, negative and significant correlations between the pairs of parameters at 95% confidence level. Amongst the sampling and control stations, some parameters had no significant difference (p > 0.05), however some differences were statistically significant (p < 0.05). In conclusion, Nembe Creek is marginally more polluted during the dry season than during the wet season. Most parameters on the Person's Correlation matrix were connected with each other based on the metrics. However, some parameters such as metals, do not significantly correlate with one another, indicating that the sources of contamination may have originated from various places. It is possible that the source may not predominantly originate from oil exploration activities but may involve other natural, geological and anthropogenic activities.
Published: 17 August 2022
International Research Journal of Pure and Applied Chemistry pp 29-47; https://doi.org/10.9734/irjpac/2022/v23i430471
Effluents received by surface water increase the concentration of heavy metals and nutrients in the water to a level that is harmful to the aquatic organism and pose a health risk to humans. Santa Barbara River is known for its rich biodiversity; and is a fishing site in Bayelsa state, Nigeria. This study examines the physicochemical characteristics of waters in the Santa Barbara River to ascertain anthropogenic influence on the water quality. In two seasons (wet and dry), surface water samples were collected from 20 sampling stations along the Santa Barbara River and from 4 control points and analyzed according to standard methods and procedures. Total suspended solids, polyaromatic hydrocarbons, and sodium were the only parameters that showed a statistical difference between values obtained in the control and study area (p > 0.05) at 95% confidence interval. The results of polyaromatic hydrocarbons, lead, chromium and sulphate observed indicated anthropogenic influence on the water quality that may be due to the use of lead in fishing net, combustion of fossil fuel, and waste discharge into the River. Impact mitigation measures are therefore recommended to improve the water quality of the River.
Published: 6 August 2022
International Research Journal of Pure and Applied Chemistry pp 23-28; https://doi.org/10.9734/irjpac/2022/v23i430470
This study evaluates the hepatic effects of caladium hortulanum leaf extract on wistar albino rats. A total of twenty-four (24) rats were randomly divided into 4 groups labeled A, B, C and D and kept in a well-ventilated room. Group A served as control and these rats were fed distilled water. Rats in the groups B, C, and D were given three (3) different doses of the leaf extract (1.5, 3.5 and 5.0mL/Kgbw) respectively. They were administered once daily for 14 and 28 days consecutively. Animals were sacrificed 24 hours after the last treatment. Blood samples were collected into heparinized sample bottles for analysis. All liver enzymes and histology results were normal for short term use in this study. Alkaline phosphatase was increased in a dose dependent manner when used in the long term. Histopathological changes were seen in all doses when Caladium hortulanum leaf extract was used in the long term. This suggests that this medicinal plant cause some degree of hepatic damage when used for continuously for long periods at a time. Care should therefore be taken with their use, prescriptions reviewed as needed and regular monitoring of liver function should be instituted.
Published: 3 August 2022
International Research Journal of Pure and Applied Chemistry pp 16-22; https://doi.org/10.9734/irjpac/2022/v23i430469
DFT Calculations were performed on Oxazole, Pyrazole, Imidazole, Isoxazole, Thiazole and Isothiazole as corrosion inhibitors for Al with full optimization of geometries in DFT-B3LYP/6-31 G*Level (d, P( to find a relation between the molecular structure and corrosion inhibition. The electronic properties such as the energy of the highest molecular orbital that is occupied (HOMO), the energy of lowest unoccupied orbital (LUMO), the energy gap (LUMO–HOMO), quantum chemical parameters such as hardness, softness, the fraction of the electron transferred, and the electrophilicity index. In order to know the relationship of molecular structure and corrosion inhibition on surface of the quantum chemical parameters, boundary orbital's isothiazole has been found the highest anti-corrosion efficiency as compared to other.
Published: 21 July 2022
International Research Journal of Pure and Applied Chemistry pp 1-15; https://doi.org/10.9734/irjpac/2022/v23i430467
The percent organic carbon (%OC) is an important soil fertility measure that has important implications in agricultural productivity and food security. In this study, a UV-visible spectrophotometric technique was investigated and applied to quantify %OC from selected soil samples along a river basin that traverses agricultural farmlands, a forest and sewage treatment lagoons for a comparative survey purposes. The study was based on the measurement of absorbance of Cr(III) species that arise from oxidation of sucrose (which is 42.11% carbon) by dichromate ions which contain Cr(VI) species. The uv-visible spectrophotometric double beam wavelength scan measurements elucidated the conversion of Cr(VI) to Cr(III) ions and a calibration plot was developed with r2= 0.99. The analyte peak was identified in the region from 750 nm to 550 nm (the absorbing Cr(iii) species) with a turning point maximum at 576 nm. The kinetic profile of sucrose oxidation by the dichromate ions was studied via absorbance of Cr(III) and Cr(VI) as a function of the reaction time and was used to characterize the reaction model. The absorbance of Cr(III) as a function of reaction time fitted best into the non-linear Belehradek power function equation y=a(x-b)c,, where y = absorbance; x = time(s); a, b, c = are constants (r2 of 0.91). Kinetic analysis revealed that the reaction that leads to the formation of Cr(III) during sucrose oxidation proceeds via pseudo first-order kinetics (r2= 0.83). A comparative quantitative analysis indicated that the sewage treatment lagoons had the highest %OC content at about 5.5-6.6%OC. The soils sampled from the forest regions had about 4.6-5.8%OC whereas the river bank soils had the lowest levels at about 2.0-2.5%OC. A statistical t-test analysis showed that the %OC levels in sub-soils were significantly higher than those of the top-soils (p > 0.05 at 95% CI).
Published: 18 July 2022
International Research Journal of Pure and Applied Chemistry pp 47-52; https://doi.org/10.9734/irjpac/2022/v23i330466
Physicochemical and acoustic propertie of liquid mixtures give knowlegeble information behaviour and interactions studies of liquids. Ultrasonic studies in liquids and solutions provide some valuable information about the structure and interaction in such systems. Ultrasonic velocity and density have been proved to be important properties to test the validity of liquid state model. The ultrasonic velocity (U) and density (ρ) of the binary liquid mixtures Chlorobenzene (polar)+Cyclopentyl methyl ether (nonpolar) [system I] and Methyl acrylate (polar) +Cyclopentyl methyl ether (nonpolar) [system II] are measured at 298.15 K temp. with pure components. With the help of these measured properties are calculated excess acoustic parameters using standard relations. Excess acoustic parameters are used as a qualitative and quantitative analysis in multicomponent liquid mixtures. The sign and magnitude of excess parameters provided information of different type interactions. Structural chemistry is related to the interactions involved in the liquid systems. structural effects also define nature and bonding of both liquid mixture system I and II.
Published: 18 July 2022
International Research Journal of Pure and Applied Chemistry pp 35-46; https://doi.org/10.9734/irjpac/2022/v23i330465
Aims: To assess the vitamin content of locusts, lake flies, grasshoppers, and termites when fresh, sun-dried, oven-dried, and defatted. Study Design: Whole insect samples were sun-dried and oven-dried. Due to their high-fat content, termites and grasshoppers were subjected to an additional defatting step after the sun-drying and oven-drying. Place and Duration of Study: The study was carried out in Kenyatta University's food science lab from August to December 2020. Methodology: Prepared insect samples were ground and analyzed for vitamins using high-performance liquid chromatography (HPLC). Analysis was done in triplicates and results were expressed in mg/100g of dry insect sample. Results: Fresh insect samples had higher vitamin concentrations compared to the processed samples. For ascorbic acid, there was no significant difference between; a) sun-dried and defatted sun-dried termites (p=0.79), b) oven-dried and defatted oven-dried termites (p=0.51), c) defatted oven-dried and defatted sun-dried grasshoppers (p=0.22) and d) sun-dried, and defatted oven-dried grasshoppers (p=0.59). For thiamine, pyridoxine, riboflavin, and α-tocopherol there was a significant difference for all the samples in all the insects (p<0.0001). For niacin, fresh, sun-dried, oven-dried, and defatted oven-dried termites showed no significant difference in concentration (p=0.22). However, there was a significant difference for the other insects (p<0.0001). For beta-carotene, only oven-dried and sun-dried grasshoppers didn’t significantly differ (p=0.76). Degradation for water-soluble vitamins was highest in sun-dried samples, while fat-soluble vitamins were highest in oven-dried samples. Conclusion: Fresh insects contain vitamins that meet the recommended dietary allowance (RDA) values for children up to 36 months, except for beta-carotene. Processing significantly reduces the vitamin levels to below RDA values except for ascorbic acid, thiamine, and alpha-tocopherol in lake flies and termites, which can be used to formulate complementary foods to meet 100% of the RDA.