Open Access Original Research Article

Study of Water Quality of the Ebrié Lagoon and Proposal of Toxin Structures in Relation to Algal Efflorescences

MEL Hayo Vianney, OUFFOUE Koffi Sébastien, BAMBA Kafoumba, ZOAKOUMA Roger Simplice Pépin, DIABAGATE Dangui, ZIAO Nahossé, OUATTARA Lassiné

International Research Journal of Pure and Applied Chemistry, Page 1-18
DOI: 10.9734/irjpac/2021/v22i730417

Aims: The aim of this work is to know the interrelationships of the physicochemical parameters likely to explain algal blooms and to identify the potential structures of molecules that can be secreted in an Ivorian lagoon environment: the Ebrié lagoon.

Methodology: Nine stations, selected according to natural influences and anthropogenic pressure, were subject to physicochemical monitoring. It consisted of in situ measurements (temperature, salinity, dissolved oxygen, electrical conductivity) and chemical analyses in the laboratory (pH, nitrates, nitrites). In addition to these measurements, observations were noted in the field, namely the climatology of the day, the colour and smell of the water, the presence of algae (micro and / or macroalgae).

Results: Our results showed that the waters of the Ebrié lagoon are warm (T > 25 °C), with a pH between 6 and 9 and variable salinity. Salinity would be a discriminating factor for the presence of macroalgae. The nutrients levels (nitrates and nitrites) remain within the limits of acceptability.

Conclusion: The waters in our study area are favorable for algal blooms. Given the nuisances associated with algal blooms, the study proposes some structures of toxins which can be secreted on the basis of a literature review.

Open Access Original Research Article

QSPR/QSAR Modelling of the Antioxidant Properties of Some Flavonoids

R. Chabi Doco, M. T. A. Kpota Houngue, Urbain A. Kuevi, Y. G. S. Atohoun

International Research Journal of Pure and Applied Chemistry, Page 19-34
DOI: 10.9734/irjpac/2021/v22i730418

Several methods exist when seeking to experimentally evaluate the antioxidant properties of a natural bioactive substance. In the case of flavonoids, the methods used are mainly based on the experimental determination of the percentage of inhibition (IC50) or the redox potential (E).

In the present work, a prediction study of the redox potential E and the inhibitory concentration LogIC50 was carried out, using the AM1 and HF/6-311G(d,p) method.

At the end of this study, three (03) QSPR models were validated and retained, one (01) for the prediction of the redox potential and four (02) for the prediction of the inhibitory concentration :

  • The Redox Prediction Model, developed at the AM1 approximation level, for which 96.43 of the experimental variance is explained by the descriptors :

E= -0,29 + 0,22EHomo + 0,11ELumo - 0,05

  • The Inhibitory Concentration Prediction Models, developed at the AM1 level, for which 96.35⁒ of the experimental variance is explained by the descriptors :

LogIC50 = -4,92 + 11,37EHomo + 34,36ELumo + 0,67

  • The Inhibitory Concentration Prediction Model, developed at the HF/6-311G level (d, p), for which 99.96⁒ of the experimental variance is explained by the descriptors. LogIC50 = 62,40 + 80,25 EHomo - 28,44Elumo + 52,01S - 71,26 η - 6,11μ

The development of these QSPR models represents a significant advance in predicting the antioxidant properties of bioactive molecules such as flavonoids based on descriptors calculated by quantum chemical methods.

Open Access Original Research Article

Suggestion Petroleum Coke from Iraq Oil Mix. (T-21A+T-5) & PF2 as Alternative Fuel for Cement and Metallurgy

Sherwan Mohammad Simo, Salah Aldin Naman, Kanaan Ramadan Ahmed, Akhmetov Arslan Faritovich, Lapshin Igor Gennadievich

International Research Journal of Pure and Applied Chemistry, Page 35-47
DOI: 10.9734/irjpac/2021/v22i730419

The feasibility of utilizing petroleum coke as an alternative fuel for cement kilns and other industries was suggesting. The feedstock using in this study are mixture (T-21A+T-5) Tawke and Shekhan PF2 AT residues were obtained from two Iraqi-Kurdistan crude oils by removing distillates boiling point up to 350°C  using the atmospheric distillation unit. The coking processing of AT residues at high temperatures to produce gas, coking distillates and petroleum coke. Coking of AT residues were carried out at temperature 450-460°C and atmospheric pressure, at this temperature, the duration of heat treatment of the feed was 2h. 45 min for Tawke and 2h. 15 min for Shekhan. The choice of temperature and time of the experiments was made on the basis that a lower temperature increases the duration of the process, and at a higher temperature a significant reduction in the duration of the process according to GOST methods, it becomes difficult to obtain the target product with the required content of volatile substances. An increase in the duration of the coking process about 3 hours and more in all cases leads to a decrease in the content of volatile substances. The study was suggested petroleum coke can be using instead of fuel oil on industry effectiveness in cost reduction when switched over from fuel oil to petroleum coke. in the last of this work, after all the measurements and characteristic obtained, two types of treatment scheme were proposed for how to refine these types of crude oils, which give petroleum products with a high sulfur content. The research proposed the technological, ecological and economic aspects of petroleum coke as fuel, including high sulfur content, use as energy in the electrical field (electro energy), and as an alternative fuel for cement production and metallurgical manufacture.

Open Access Original Research Article

Identification of Five Acylated Anthocyanins and Determination of Antioxidant Contents of Total Extracts of a Purple-Fleshed Ipomoea batatas L. Variety Grown in Burkina Faso

Dominique Saga Kaboré, Adama Héma, Elie Kabré, Raoul Bazié, Abdoul Karim Sakira, Moumouni Koala, Paul-André Koussao Somé, Eloi Palé, Touridomon Issa Somé, Pierre Duez

International Research Journal of Pure and Applied Chemistry, Page 48-66
DOI: 10.9734/irjpac/2021/v22i730420

Anthocyanins are bioactive compounds, which thanks to their anti-free radical properties, can protect the human body against oxidative stress. The latter can cause many diseases, such as cancer, aging. The extract of the green cap purple variety of the sweet potato (Ipomoea batatas L.) is active against the radical ABTS. Its antioxidant content is estimated at 0.183 mg E TEAC/ g fresh material. The characterization of anthocyanins was performed by high performance liquid chromatography-mass spectrometry-UV (HPLC-MS-UV) and high performance liquid chromatography-mass spectrometry (HPLC-MS/MS) analyses.  These analyses allowed the identification of five anthocyanic compounds. These are: cyanidin 3-(6''-caffeoyl- 6'''-p-hydroxybenzoyl sophoroside) -5-glucoside; cyanidin 3-(6''-feruloyl 6'''-caffeoyl sophoroside) -5-glucoside; peonidin 3-(6'''-caffeoyl sophoroside)-5-glucoside; peonidin 3-(6''-caffeoyl-6'''-p-hydroxybenzoyl sophoroside) -5-glucoside; and peonidin 3-(6''-feruloyl -6'''-caffeoyl sophoroside)-5-glucoside.

Open Access Original Research Article

Degradation of Remazol Black dye from Aqueous Solution by Heterogeneous NH3(MoO3)3/H2O2 System

Kouakou Yao Urbain, Kambiré Ollo, Gnonsoro Urbain Paul, Eroi N’goran Sévérin, Trokourey Albert

International Research Journal of Pure and Applied Chemistry, Page 67-78
DOI: 10.9734/irjpac/2021/v22i730421

Aims: The pollution of the environment by organic dyes in water is a matter of great concern. Wastewater containing dyes is difficult to treat by conventional wastewater treatment methods such as coagulation, ozonation, biological treatment, etc. This is why the implementation of an effective method by not generating pollutants secondary is necessary.

The objective of this work is to study the degradation of remazol black, an azo dye, by the coupling of hydrogen peroxide - molybdenum oxide nanoparticle. The nanoparticles were synthesized by the aqueous sol-gel method using a reflux assembly.

Study Design: Random design.

Methodology: The nanoparticles were synthesized by the aqueous sol-gel method using a reflux assembly and then characterized by X-ray diffraction and using software origin to determine the particles size by Scherrer's formula. The influence of hydrogen peroxide, molybdenum oxide and hydrogen peroxide / molybdenum oxide coupling, and the degradation kinetics of remazol black were studied. We also studied the influence of the pH of the solution, the mass of molybdenum nanoparticles and the concentration of remazol black on the dye degradation process.

Results: The results showed that the synthesized oxide is ammonium molybdenum trioxide NH3(MoO3)3) with a hexagonal structure and size 22.79 nm. The study of the catalytic effect revealed a degradation rate of 17%, 0.83% and 42% respectively for H2O2, NH3(MoO3)3 and the coupling NH3(MoO3)3/H2O2. The study also showed that the degradation of remazol black by the couple NH3(MoO3)3 /H2O2 is better at pH = 4 and for a mass of nanoparticles of 400 mg. This degradation kinetics are pseudo 1st order. In addition, the degradation rate decreases when the concentration of remazol black increases. The efficiency of the coupling (NH3(MoO3)3 / H2O2 showed at ambient temperature, that it was possible to remove about 60% of the initial color of remazol black from the water in a batch reaction.

Conclusion: The reflux method makes it possible to synthesize molybdenum nanoparticles. The molybdenum oxide hetero-Fenton process is effective in removing remazol black dye from water.