Chemical Science International Journal <p style="text-align: justify;"><strong>Chemical Science International Journal&nbsp;(ISSN:&nbsp;2456-706X)&nbsp;</strong>aims to publish&nbsp;high quality papers (<a href="/index.php/CSIJ/general-guideline-for-authors">Click here for Types of paper</a>)&nbsp;in all aspects of chemical science. The journal also encourages the submission of useful reports of negative results. This is a quality controlled,&nbsp;OPEN&nbsp;peer reviewed, open access INTERNATIONAL journal.</p> en-US (Chemical Science International Journal) (Chemical Science International Journal) Sat, 11 Apr 2020 11:12:22 +0000 OJS 60 Evaluation of Phytochemical, Antimicrobial and Antioxidant Capacities of Pennisetum purpureum (Schumach) Extracts <p>Medicinal plants are valuable natural sources for the development of potentially safe drugs. The biological activities associated with these plants are due to the presence of certain phytochemicals that act individually or synergistically. Thus, this study examined the phytochemical components, antioxidant and antimicrobial activities of n-hexane, ethylacetate and methanolic extracts of&nbsp;<em>Pennisetum purpureum</em> (Schumach). Qualitative and quantitative phytochemical assays of&nbsp;<em>P. purpureum</em>&nbsp;showed the presence of alkaloids (0.004%), saponins (0.002%), flavonoids (0.021%), steroids, terpenoids and glycosides (0.008%). Methanol, n-hexane and ethylacetate extracts of <em>P. purpureum</em> were examined for antimicrobial activity using the disc diffusion method. Six microbial strains were exposed to six different concentrations of each extracts; 200 mg/ml, 100 mg/ml, 50 mg/ml, 25 mg/ml, 12.5 mg/ml and 6.25 mg/ml. The three extracts demonstrated varied concentration-dependent antimicrobial activities against the test organisms. The methanolic extract showed antibacterial activity against&nbsp;<em>E. coli, S. aureus, B. cereus</em> and antifungal activity against <em>T. mentagrophyte </em>and <em>A. niger</em>. Among all extracts, the methanolic extract of <em>P. purpureum </em>exhibited relatively strong antifungal activity against&nbsp;<em>A. niger </em>(10.3±0.12 mm) when compared to the standard antifungal agent, fluconazole (13.9±0.12 mm). Furthermore, antioxidant activities were spectrophotometrically studied using vitamin C as standard; methanol and ethylacetate extracts of&nbsp;<em>P. purpureum </em>showed pronounced scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH); and had a potent reductive ability on ferric ion and phosphomolybdate. However, only the non-polar extract of&nbsp;<em>P. purpureum</em>&nbsp;showed a non-significant correlation and significant differences when compared to vitamin C. Antioxidant activities of the plant extracts were observed in the order of methanol &gt;ethylacetate&gt; n-hexane extracts. The results showed that <em>P. purpureum </em>contains phytochemicals that significantly contributed to the observed antimicrobial and antioxidant abilities of the plant and could be used as a potential source for the development of novel therapeutic drugs.</p> I. R. Jack, P. D. Clark, G. I. Ndukwe ##submission.copyrightStatement## Sat, 11 Apr 2020 00:00:00 +0000 Differential Pulse Polarography Method for the Determination of Trace Fe, Ni, Pb, Zn, Se and Cu in Black Tea Leaves <p>In this work a new and simple polarographic method has been established for the determination of trace elements present in tea. After digestion with acids, tea samples were analyzed using various electrolytes such as acetate and ammonia at different pH values in the presence or absence of EDTA. Thus, it was possible tochoosethe best medium for the determination of6 trace elements in one tea sample. Polarographic peaks of copper and iron could be separated in HAc at about pH =7 in the presence of EDTA and their quantities were determined. Ni and Zn peaks could be separated and determined in ammonia buffer at about pH= 10. Lead could be determined at pH= 2HAc electrolyte. Selenite, was determined from its hydrogen catalytic peak in KCl, pH= 2 medium in the presence of Mo (VI). The LOD was found as 2.4x10<sup>-7</sup> for instead of (S/N=3).The trace element ranges in black tea were found as, Fe 35 μg/g, Cu 45 μg/g, Ni 19 μg/g, Zn&nbsp; 22 μg/g, Pb 28 μg/g and Se 77&nbsp; μg/g.</p> Sukru Kalaycı, Guler Somer ##submission.copyrightStatement## Sat, 25 Apr 2020 00:00:00 +0000 Evaluation of Cytotoxic Profile of Some Chalcone Derivatives with Antimalarial Properties <p>Malaria continues to kill thousands of people worldwide. People South of the Sahara are paying the heaviest price for this epidemic. In addition, the resistance of <em>Plasmodium falciparum</em> which spreads to artemisinin derivatives becomes worrying. To respond to this emergency, the search for new molecules effective against the parasite is essential. Otherwise, chalcones have shown their potential as an effective pharmaceutical agent in numerous studies. However, despite their mainly antiparasitic efficacy, several compounds have been shown to be cytotoxic. This study aimed to assess the cytotoxic profile of chalcone derivatives. Cytotoxicity tests were carried out according to the method described by Taylor and collaborators on Vero cells. The 96-well plates were used in carrying out this study, 100 µl of the compounds were added with concentrations ranging from 7.5 to 1000 µg/ml in DMEM. The results obtained report three compounds derivatives (Chal_B14, Chal_B17 &amp; Chal_SCA03) no-cytotoxic with LDH product values between 129 - 132.5 U/L and ATP ranging from 8.55 to 13.6 RLU. The IC<sub>50s</sub> for no-cytotoxic compounds ranged from 102 to 236 µM. On the other hand, the cytotoxic compounds had IC<sub>50s</sub> of less than 30 µM.</p> <p>The results of this study show that the derivatives Chal_B14, Chal_B17 &amp; Chal_SCA03 are candidate compounds with a view to finding new molecules.</p> Marius Trésor Dable, Mahama Ouattara, Edgard Valéry Adjogoua, Konan Dominique Tano, Akissi Jeanne Koffi, Nkoua Badzi Cynthia, William Yavo ##submission.copyrightStatement## Wed, 06 May 2020 00:00:00 +0000