Open Access Original Research Article

An Enzyme-based Spectrophotometric Method for the Determination of Phenolic Compound (2- Methoxyphenol) Using Peroxidase from Ipomea batata

A. M. Magomya, G. G. Yebpella, U. C. Okpaegbe, H. Ataitiya

Asian Journal of Applied Chemistry Research, Page 11-18
DOI: 10.9734/ajacr/2022/v12i2216

Phenolic compounds and their derivatives are considered priority pollutants because they are harmful to living organisms even at low concentrations. Due to their toxicity and persistence in the environment, many efforts are been made to develop simple and effective methods for their determination. This study describes a peroxidase-based method for the quantitative determination of a named phenolic compound. The method is based on the oxido-reductase activity of peroxidase in a H2O2/2-Methoxyphenol system. Calibration curve of peroxidase activity (absorbance) against the phenol concentration forms the basis for its quantitative estimation. Factors influencing the reaction were evaluated and optimized; Optimum pH and temperature were 6 and 40°C respectively while optimum reaction time was 6 minutes.  The calibration curve for the analyte was linear (R2 =0.998) within the concentration range of 0.01–5 mM.  Repeatability of analysis was 3.8% RSD for 7 replicate measurements. Recovery tests for the analyte in water samples gave values between 85.33 – 112%.

Open Access Original Research Article

Physicochemical Quality and Health Risks Associated with Use of Water from Nyamwamba River, Kasese, Western Uganda

Jockus Masereka, Denis Byamugisha, Christopher Adaku

Asian Journal of Applied Chemistry Research, Page 19-33
DOI: 10.9734/ajacr/2022/v12i2217

Aim: In Kasese district of Western Uganda, farmers cultivating near Nyamwamba River (NR) experience crop wilting whenever the river banks burst. Increased cases of cancer and ulcers in the district is anecdotally blamed on ingestion of contaminated water from water resources polluted by tailings from Kilembe copper mines. Sand miners attested that mining in NR caused body irritations and itching while drinking water from the same river results in abdominal complications in infants. The aim of this study was to assess the seasonal variations in the physicochemical parameters and heavy metals (HMs) content of water from NR, and the associated health risks.

Place and Duration of Study: The experiments were done at the Department of Chemistry, Faculty of Science, Mbarara University of Science and Technology, Uganda from 2018 to 2019.

Methodology: This study employed quantitative research design. Water was sampled from down, middle and upstream of NR and Mubuku River, Western Uganda during the dry and wet seasons. The samples were analyzed for physicochemical parameters (pH, conductivity, total dissolved solids, total suspended soils) and HMs: chromium (Cr), cadmium (Cd), zinc (Zn), iron (Fe), lead (Pb), arsenic (As) and copper (Cu) by atomic absorption spectrometry. The estimated daily intake (EDI), target harzard quotient (THQ) and cancer risks were calculated to explore if there are any carcinogenic and non-carcinogenic health risks that could arise from ingestion and dermal contact with water from NR.

Results: Most physicochemical parameters of the water samples only met WHO guidelines for drinking water in the upstream. The mean concentration of Fe, Cu, Pb, Zn, Cr, Cd and As were 0.90-29.66 mg/L, 0.21-10.74 mg/L, 0.40-8.21 mg/L, 1.10-13.47 mg/L, 0.79-13.47 mg/L, 0.05-1.40 mg/L and 0.22-4.34 mg/L, respectively. Wet season recorded higher HMs concentrations when compared to the dry season, with all its samples exceeding the WHO guidelines for drinking water. There was an extremely high concentration of HMs in the upstream samples than expected. Health risk assessment indicated that the EDI through dermal contact ranged from 0.015 to 4.150 mg/kg/day while through ingestion of contaminated water, the values ranged from 0.008 × 10-6 to 38.266 × 10-6 mg/Lday. Some of the EDI doses were higher than corresponding reference doses for ingestion and contact with the HMs in water. THQ and total THQ exceeded 1 while cancer risk values were beyond the US EPA cancer risk borderline.

Conclusion: This study revealed that there are serious non-carcinogenic and carcinogenic health risks that could arise from consumption and contact with water from NR. Future studies should examine the relationship between the occurrence of trace metals in food stuffs with cancer, ulcers and other associated diseases in the area.

Open Access Original Research Article

Preparation and Evaluation of 1, 2-Dibromoethane Product as Oil Field Emulsion Breaker

Okoye Ogechi, Onyewuchi Akaranta, Uche Chukwu

Asian Journal of Applied Chemistry Research, Page 34-52
DOI: 10.9734/ajacr/2022/v12i2218

Quercetin rich compound and cardanol rich compound were extracted and modified via the William ether synthesis using 1,2-dibromoethane in the presence of a base catalyst. The FTIR spectral analysis of the modified product confirmed its chemical modification. The modified product MRCNSL was evaluated as emulsion breakers. Medium crude and seawater, characterized with ASTM standards were used in producing laboratory-simulated crude oil emulsions at varying crude oil: water mixing ratios of 90:10, 70:30 and 50:50. Performance of MRCNSL demulsifier was evaluated based on variation in dosage (10 ppm – 50 ppm), water content (10%, 30% and 50%), and solvent types (ethanol, butanol, xylene and a binary mixture of butanol and xylene in ratio 30:70, 50:50 and 70:30) at room temperature within a 3-hr period via bottle testing. Results obtained showed that water separation increases with demulsifier concentration and emulsion water content respectively, though water separation varied among the solvents. In conclusion, the evaluated MRCNSL product possesses emulsion breaking potential using binary mixture of Butanol/xylene (70:30) as solvent at shorter times. This may be due to the synergetic effect of Butanol as a solvent, thus, Butanol/xylene (70:30) should be considered as solvent substitute for xylene due to reduced cost and less toxicity levels, unlike using xylene alone which is toxic and expensive.

Open Access Original Research Article

Characterization of Chemical Constituent and Biological Activity of Roots from Cleistanthus oblonggifolius (Roxb.) Mull. Arg

Saranya Wattananon, Wilart Pompimon, Phansuang Udomputtimekakul, Puttinan Maepowpan, Thanatcha Taratong, Amornrat Khamkaew, Atchariyaporn Mookaewkrue, Raksina Boonthadang, Nopawit Khamto, Puracheth Rithchumpon, Narong Nuntasaen

Asian Journal of Applied Chemistry Research, Page 53-60
DOI: 10.9734/ajacr/2022/v12i2219

Background: C. oblongifolius is a species of Asian trees, originally described by William Roxburgh and later placed by Johannes Müller Argoviensis; it is now included in the family Phyllanthaceae. Distributed throughout Indochina and Malesia, its name in Vietnam is cọc rào; it has been recorded from the Andaman & Nicobar Islands, Australia (Queensland), Bangladesh, Borneo, Cambodia, Java, Lesser Sunda Islands, peninsular Malaysia, Maluku, Myanmar, New Guinea, Philippines, Solomon Islands, Sulawesi, Sumatera, Vietnam and Thailand. Several species of this genus are highly poisonous (C. collinus), some are brewed for treating dysentery (C. decurrens), and used for treatment of asthma (C. myrianthus).

Objective: This study was conducted to investigate the effect of crude extract and purified substance on inhibition of AIDS and cancer.

Methods: Phytochemical studies were extracts from these solvents used for the study: hexane, ethyl acetate and methanol. The dried herbs were ground and extracted by chromatography. Extracts and compound have been tested for HIV-1 RT, anti-syncytium and cytotoxicity. The obtained purification compounds were used to determine the structure by spectroscopic techniques such as UV. IR, NMR and MS.

Results: The study found that compound 3-O-methylellagic acid 4'-O-alpha-L-rhamnopyranoside from the roots of this plant, it was also found that ethyl acetate and methanol class extracts inhibited anti-HIV-1 RT up to 100% and 65% pure substance. For all extracts and purified compounds, syncytium inhibition assay showed inhibition HIV with EC50 <7.8 µM, TI>2.31. SH-SY5Y anticancer was showed with ED50 = 6.7 µM.

Conclusion: C. oblongifolius extract, most of these fractions were potent in inhibiting HIV-1 RT and syncytium (MC99+1A2) inhibition. In addition, hexane extract inhibited the growth of SH-SY5Y cancer cells more than other cancer cells. However, the isolated purified compound only had an inhibitory effect on HT-29 cells with ED50 10.11 µg/mL.

Open Access Review Article

Production, Properties and Applications of Xylooligosaccharides (XOS): A Review

C. E. Anarado, F. M. Chukwubueze, O. F. Obumselu, N. U. Ejimofor, N. P. Okafor, C. J. O. Anarado, C. B. Nsofor

Asian Journal of Applied Chemistry Research, Page 1-10
DOI: 10.9734/ajacr/2022/v12i2215

Xylooligosaccharides derived from Xylan, significant component of hemicellulose in lignocellulosic plant biomass, are essential raw materials used in the food, pharmaceutical and agricultural industries. They find application in these industries due to their unique physicochemical properties such as pH stability, growth regulatory ability, and anti-allergic property. In addition, they have been shown to exhibit promising antimicrobial, anti-cancer, antioxidant and anti-inflammatory activities. Xylooligosaccharides convert waste into valuable foods, pharmaceuticals, and agricultural products, promoting health, the economy, and the environment.