Test Organisms Research Articles

The Phytochemical Composition and Antibacterial Effects of Allium sativum Clove Extracts on Some Enteric Bacterial Pathogens

In this study, the phytochemicals present in the cloves of Allium sativum were determined, and their antibacterial activities against some enteric bacterial pathogens were assessed. The phytochemical constituents were determined after the extraction process was completed using water and ethanol as the solvents. Furthermore, the aqueous and ethanolic extracts of A. sativum were tested against Escherichia coli, Salmonella typhi and Shigella dysenteriae isolated from faeces of gastroenteritis patients. The agar diffusion technique (punch method) was used for this. Additionally, the extracts' minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. The mean values of the zones of inhibition obtained were statistically analyzed using ANOVA. The least significant difference was determined according to the LSD test at P<0.05. The results of the phytochemical analysis revealed the presence of saponin, alkaloids, flavonoids, and tannins. Furthermore, the antibacterial susceptibility test showed that the aqueous and ethanolic extracts possess antibacterial properties against all the test organisms. The ethanolic extract at the concentration of 500mg/ml had zones of inhibition of 29.00b against E. coli, 24.00b against S. dysenteriae and the lowest 20.00b against S. typhi. On the other hand, at that same concentration, the aqueous extract had zones of inhibition of 20.00b against E. coli and 18.00b against S. dysenteriae and S. typhi. This study suggests that A. sativum extracts possess antibacterial properties. Furthermore, since the ethanolic extract was more effective than the aqueous extract, it could be that the antibacterial potency of A. sativum is solvent-dependent. In conclusion, the findings from this study suggest that further purification of the constituents of the plant might lead to the development of novel antibiotics.

Acute toxicity of rich triethylene glycol on juvenile African freshwater catfish (Clarias gariepinus) around a natural gas dehydration facility

Triethylene glycol (TEG) removes equilibrium water from natural gas but may spill during equipment maintenance and other poor safety practices. Studies on the toxicity of rich TEG in aquatic habitats are scarce. In this study, the toxicity of rich TEG on freshwater juvenile African catfish (Clarias gariepinus) test organism was conducted. The experimental design for the toxicity tests was 3 × 5 × 6 factor in a randomized complete block design, with six levels of treatment, observed at five intervals and in three replicates. The acute toxicity was carried out by exposing them to various lethal concentrations of the Rich TEG in solution. Physicochemical parameters, including temperature, dissolved oxygen, pH, conductivity, and total dissolved solids, were measured and recorded for five test concentrations of 25.92, 12.96, 6.48, 3.24, 1.62, and 0.0 ml/l (control). The concentration responses for the fish mortality at 24, 48, 72, and 96 h were also derived. No mortality was observed between Rich TEG concentrations of 0 ml/l to 25.92 ml/l after 72 h of exposure. However, some mortality was observed between 1.62 ml/l to 25.92 ml/l after 96 h of exposure. The highest concentration of 25.92 ml/l recorded a higher mortality of 6.0 ± 0.4, which is an average of 60%, while the lowest mortality was recorded in the control (0 ml/l), at an average of 0% mortality rate. The results underscore the concentration-dependent effects of rich TEG on the test organism, highlighting the need for targeted attention to higher concentration levels.

Exploring the Antibacterial Properties of Vernonia amygdalina (Bitter Leaf) Extract: A Potential Alternative to Conventional Antibiotics

As part of the ongoing search for potent and resistance-free antibacterial medicinal plants, this study aimed to evaluate the antibacterial properties of the plant extract of Vernonia amygdalina, commonly known as bitter leaf. Standard procedures were used to provide a potential cheap alternative to conventional medication for treating bacterial infections. The aqueous extract of V. amygdalina leaves was prepared and subjected to phytochemical screening, which revealed the presence of tannins, phlobatannins, saponins, terpenoids, cardiac glycosides and alkaloids. The antibacterial activity of the extract was tested against the gram-positive bacterium Staphylococcus aureus and the gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli using the agar well diffusion method. The extract showed moderate antibacterial activity, exhibiting 10 mm and 8 mm zones of inhibition against S. aureus and P. aeruginosa respectively at a concentration of 20 mg/ml. However, it displayed no activity against E. coli. In comparison, the standard antibiotic gentamicin produced larger zones of inhibition of 33.5 mm, 27 mm, and 23.5 mm against the respective test organisms. The results suggest that V. amygdalina extract had greater antibacterial activity on the gram-positive S. aureus than on the gram-negative microorganisms tested. The presence of phytochemicals like tannins, saponins and alkaloids in the extract may contribute to its antibacterial properties. Further research is warranted to fully elucidate the medicinal potential of V. amygdalina and isolate the active compounds responsible for the observed antimicrobial effects. Overall, the findings provide a scientific basis for the traditional use of this plant in treating bacterial infections. Keywords: Vernonia amygdalina, Antibacterial activity, Phytochemicals, Antimicrobial resistance, Traditional. medicine

Evaluation of sponge wipe surface sampling for collection of potential surrogates for non-spore-forming bioterrorism agents.

Evaluate the efficacy of sponge wipe sampling at recovering potential bacterial surrogates for Category A and B non-spore-forming bacterial bioterrorism agents from hard, nonporous surfaces. A literature survey identified seven nonpathogenic bacteria as potential surrogates for selected Category A and B non-spore-forming bacterial agents. Small (2 × 4 cm) and large (35.6 × 35.6 cm) coupons made from either stainless steel, plastic, or glass, were inoculated and utilized to assess persistence and surface sampling efficiency, respectively. Three commercially available premoistened sponge wipes (3M™, Sani-Stick®, and Solar-Cult®) were evaluated. Mean recoveries from persistence testing indicated that three microorganisms (Yersinia ruckeri, Escherichia coli, and Serratia marcescens) demonstrated sufficient persistence across all tested material types. Sampling of large inoculated (≥107 CFU per sample) coupons resulted in mean recoveries ranging from 6.6 to 3.4 Log10 CFU per sample. Mean recoveries for the Solar-Cult®, 3M™ sponge wipes, and Sani-Sticks® across all test organisms and all material types were≥5.7, ≥3.7, and≥3.4 Log10 CFU per sample, respectively. Mean recoveries for glass, stainless steel, and ABS plastic across all test organisms and all sponge types were≥3.8, ≥3.7, and≥3.4 Log10 CFU per sample, respectively. Recovery results suggest that sponge wipe sampling can effectively be used to recover non-spore-forming bacterial cells from hard, nonporous surfaces such as stainless steel, ABS plastic, and glass.

Acute Toxicity Assays with the Artemia salina Model: Assessment of Variables.

The use of the brine shrimp Artemia salina (Leach) in acute toxicity assays has great potential due to its simplicity, low cost and reproducibility. In the current study, some of the variables that can influence the reliability of the assay in terms of test organism survival, were evaluated as part of its implementation in our laboratory. The quality and type of water used, the buffer components and other parameters (salinity, pH and dissolved oxygen level), were all evaluated for optimisation purposes. DMSO (dimethyl sulphoxide) was used as the test substance in the toxicity assay, to evaluate the concentration limits as a solvent in sample preparation. Regarding the buffer salinity, pH and dissolved oxygen level, we found that a 25% to 30% deviation from the standard values did not affect the survival of the nauplii (the first-instar larval stage) under assay conditions. In summary, we corroborate the potential use of this model for the prediction of the toxic potential of substances, to inform future testing strategies.

Ecotoxicological impact of naproxen on Eisenia fetida: Unraveling soil contamination risks and the modulating role of microplastics

Soils represent crucial sinks for pharmaceuticals and microplastics, making them hotspots for pharmaceuticals and plastic pollution. Despite extensive research on the toxicity of pharmaceuticals and microplastics individually, there is limited understanding of their combined effects on soil biota. This study focused on the earthworm Eisenia fetida as test organism to evaluate the biotoxicity and bioaccumulation of the typical pharmaceutical naproxen and microplastics in earthworms. Results demonstrated that high concentrations of naproxen (100 mg kg−1) significantly increased the malondialdehyde (MDA) content, inducing lipid peroxidation. Even though the low exposure of naproxen exhibits no significant influence to Eisenia fetida, the lipid peroxidation caused by higher concentration than environmental relevant concentrations necessitate attention due to temporal and spatial concentration variability found in the soil environment. Meanwhile, microplastics caused oxidative damage to antioxidant enzymes by reducing the superoxide dismutase (SOD) activity and MDA content in earthworms. Metabolome analysis revealed increased lipid metabolism in naproxen-treated group and reduced lipid metabolism in the microplastic-treated group. The co-exposure of naproxen and microplastics exhibited a similar changing trend to the microplastics-treated group, emphasizing the significant influence of microplastics. The detection of numerous including lipids like 17-Hydroxyandrostane-3-glucuronide, lubiprostone, morroniside, and phosphorylcholine, serves to identify potential biomarkers for naproxen and microplastics exposure. Additionally, microplastics increased the concentration of naproxen in earthworms at sub-organ and subcellular level. This study contributes valuable insights into the biotoxicity and distribution of naproxen and microplastics in earthworms, enhancing our understanding of their combined ecological risk to soil biota.

Health Benefits and Antibacterial Properties of Probiotics Isolated From Fermented Food Products

As a result of the continuously expanding scientific evidence probiotic bacteria have become increasingly popular due to their beneficial effects on human health. The main objective of this study was to isolate, identify, and characterize some lactic acid bacterial strains from fermented food products as potential probiotics with antimicrobial activity against some test strains. Total four samples of fermented food products were taken (Sauerkraut, Fermented Cucumber, Idli batter and Dosa batter). The Lactic acid bacteria were isolated from these samples and the probiotics were further tested for their ability to tolerate pH, bile salt at different concentrations. The probiotic strains were found to grow at different pH and also at different conc. of bile and NaCl. These isolates exhibited high antibacterial activity when tested against the test organism (Pseudomonas, Streptococcus, Escherichia coli and Klebsiella) in well diffusion method. The present study concludes that the isolated probiotic strain from the fermented food qualifies pH, bile and NaCl tolerance tests that make an isolate to be an ideal probiotic. Probiotic strains were found to carry antimicrobial property and can be used to control gut microbiota. The result of the present study showed that the fermented food products can be used as a good source of probiotic culture.

In-vitro Evaluation of Wild Bitter Melon (Momordica charantia) Extracts against Periodontopathic Bacteria (Prevotella intermedia and Porphyromonas gingivalis) using Antibacterial, Anti-Inflammatory and Molecular Docking Analysis.

Wild bitter melon (Momordica charantia) extracts were prepared and their antibacterial and anti-biofilm assay were investigated against two different periodontopathic bacteria (Prevotella intermedia and Porphyromonas gingivalis) for the first time to the best of our knowledge based on the presence of different phytochemical compounds. Momordica charantia solvent extracts were prepared and phytochemical analysis was performed. Minimal inhibitory and bactericidal concentrations were determined. Antibacterial activity was evaluated using the standard well diffusion method. Anti-inflammatory studies on periodontal ligament (PDL) cell viability and lipopolysaccharide (LPS)-induced inflammation were performed. Molecular docking was investigated between the bioactive compound (Charantadiol A) of plant extract and biofilm-expressing genes in each test organism. Phytochemicals from ethanol extract showed promising results; alkaloids, flavonoids, phenols, and tannins were found present at considerable levels. The minimum inhibitory concentration was found to be 400 μg/mL for Prevotella intermedia and Porphyromonas gingivalis. Antibacterial activity expressed in terms of zone of inhibition showed 14 mm to 18 mm zones against the test organisms. The molecular docking report revealed the maximum binding energy of about -6.54 Kcal/Mol of binding energy between Charantadiol A and fimA of Porphyromonas gingivalis. Anti-biofilm study showed that the minimum biofilm eradication concentration (MBEC) of Momordica charantia expressed significantly good results against the test organisms. The PDL cell viability values expressed in percentage indicated the anti-inflammatory properties of Momordica charantia extracts at three different known concentrations. The findings concluded that Momordica charantia extracts have promising prospects as an anti-periodontopathic and anti-inflammatory agent.

Estimation of MBC: MIC Ratio of Herbal Extracts against Common Endodontic Pathogens

ABSTRACT Herbal extracts have evoked interest owing to the small number of terpenoids and phenolic compounds, which impart antimicrobial, antioxidant, and anti-inflammatory properties. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and minimum fungicidal concentration (MFC) of four herbal extracts (lemon grass oil, basil oil, peppermint oil, and Obicure tea extract) against endodontic pathogens along with the MIC: MBC/MFC ratio were evaluated. The antimicrobial activity by detecting the MIC of three essential oils and tea extract was evaluated against eight common endodontic pathogens by the broth dilution method, while MBC was detected by subculturing onto blood agar from the first –three to five tubes from the MIC dilution tubes (showing no turbidity), which were plated on blood agar. All herbal extracts proved to be effective antimicrobials against tested endodontic pathogens. Basil oil had a bacteriostatic effect on all the organisms (P < 0.05). Mint oil showed bacteriostatic activity on Enterococcus (E.) faecalis and Peptostreptococcus (P > 0.05). Tea extract had a bacteriostatic effect (P > 0.05) against all tested microbes except Actinomyces, Lactobacilli, Staphylococcus (S.) aureus, and Fusobacterium (F.) nucleatum. Lemon grass oil had a bactericidal effect against all the organisms and a bacteriostatic effect against Peptostreptococcus (P > 0.05). It can be concluded that basil oil showed a strong bactericidal effect on the test organisms. The MIC for the organisms ranged from 0.2 to 50 μg/ml.

The number of test organisms might influence the toxicity evaluation of hydrophobic micropollutants

Evaluating the toxicity of micropollutants forms the basis for understanding their potential risks to the ecosystem and/or human health. To accurately evaluate the toxicity of micropollutants in toxicity tests, many factors have been carefully considered, while the impact of the number of test organisms on toxicity results has rarely been taken into account. In this study, the role of the organism number on the developmental toxicity of five micropollutants was investigated using embryos of the marine polychaete Platynereis dumerilii. The toxicity of hydrophobic micropollutants was found to decrease significantly with increasing the number of embryos used in the test. A quantitative model was developed to better describe how the number of embryos affected developmental toxicity. The model showed a satisfactory fit to the raw data in all scenarios tested. The intrinsic half-maximal effective concentration EC50,int was then determined using the model. For a given compound, the EC50,int was a stable parameter that did not depend on the number of test embryos and thus provided an indication of the intrinsic toxicity of the compounds tested. Compared with the EC50 values determined with the commonly used embryo number (around 120), the EC50,int values of all tested hydrophobic micropollutants were lower. The more hydrophobic the compounds tested, the more pronounced the reduction in toxicity. This suggested that hydrophobic micropollutants could be more toxic than reported in the literature. Some suggestions were also made to eliminate the effect of the number of organisms used in the toxicity evaluation.

Green synthesis of copper nanoparticles by using pineapple peel waste: in vitro characterizations and antibacterial potential.

A considerable amount of fruit waste is being produced every day worldwide. The green synthesis of metal nanoparticles from fruit peel waste can be an innovative, cost-effective, and eco-friendly alternative to traditional methods. Copper nanoparticles (CuNPs) were synthesized by a green method using the pineapple peels extract (PLX) and copper sulfate pentahydrate. The formation of CuNPs was visually identified and detected by UV-Visible spectroscopy. The CuNPs were characterized by Fourier-transform infrared (FTIR) spectroscopy, particle size analyzer, scanning electron microscopy (SEM), and X-ray diffraction (XRD). The antioxidant and reducing power of CuNPs were conducted by %DPPH scavenging and electron transfer-based ferric reducing antioxidant power (FRAP) assay, respectively. The antibacterial properties of CuNPs were determined in gram-positive, and gram-negative bacteria. The results showed that the CuNPs were spherical in shape with mean particle size 290.5nm. The zeta potential of the nanoparticles was found to be -12.3mV indicating the instability in the colloidal state. The FTIR study confirmed the peaks of phytochemicals present in the PLX and the nanoparticles supporting the use of pineapple peels as stabilizing, reducing and capping agents. Both the DPPH and reducing power assay depicted that the synthesized CuNPs had significant antioxidant activity. However, the synthesized CuNPs had strong inhibitory capacity against both gram-positive and gram-negative test organisms. Thus, the CuNPS could be used for its viable antibacterial potential to preserve fruits, flowers, and vegetables from bacterial contamination.

New QSTR models to evaluation of imidazolium- and pyridinium-contained ionic liquids toxicity

We present machine learning studies devoted to the creation of predictive models for toxicity evaluation of imidazolium- and pyridinium-containing ionic liquids. New created predictive models were developed using the OCHEM. The predictive ability of the models was tested by cross-validation, giving a coefficient of determination q2 = 0.77–0.82. The models were applied to screen a virtual chemical library to the toxicity of ILs in Danio rerio and Daphnia magna bioassays. Models were used to predict toxicity for 25 ILs, which were then synthesized and tested in vivo. The in vivo toxicity studies found that D. magna is a more sensitive aquatic test organism than D. rerio – 67 % of the studied ILs are classified as extremely toxic with an LC50 range from 0.005 to 0.01 mg/l. At the same time, only one IL 1-dodecylpyridinium bromide with an LC50 of 0.08 mg/l is classified as extremely toxic, and 76 % are classified as slightly and moderately toxic compounds using D. rerio as a test organism. The most toxic ILs 5 and 19 were docked into the human AChE active center and demonstrated calculated binding energy values −9.5 and −9.3 kcal/mol that is comparable with the complexation of the human AChE inhibitor Donepezil, which provides insight into the potential molecular mechanisms of ILs toxicity. The created QSTR models are a successful tool for the toxicity analysis of new promising ILs. QSTR models demonstrated not only high predictive indicators but also a high percentage of correctly predicted toxicity values in vivo studies.

Modified in-vitro AATCC-100 procedure to measure viable bacteria from wound dressings.

Chronic wounds are reoccurring healthcare problems in the United States and cost up to $50 billion annually. Improper wound care results in complications such as wound debridement, surgical amputation, and increased morbidity/ mortality due to opportunistic infections. To eliminate wound infections, many antimicrobial dressings are developed and submitted to FDA for evaluation. AATCC-100 is a standard method widely used to evaluate cloth wound dressings. This method, requires enrichment, followed by culturing to measure the concentration of culturable organisms; a caveat to this method could result in neglected viable but nonculturable (VBNC) bacteria and overestimate the antimicrobial properties of wound dressings. Therefore, the objectives of this study were to assess this accepted protocol with quantitative real-time polymerase chain reaction (qRT-PCR), to measure time dependent antimicrobial efficacy of wound dressing, and to examine for potential viable bacteria but non-culturable as compared with traditional plating methods. The test organisms included opportunistic pathogens: Pseudomonas aeruginosa (ATCC 15692) and Staphylococcus aureus (ATCC 43300). To mimic a wound dressing environment, samples of commercially available wound dressings (McKesson Inc.) with silver ion (positive control) and dressings without silver ion (positive control) were assessed under sterile conditions. All samples were examined by the original protocol (the extended AATCC-100 method) and qRT-PCR. The expression of specific housekeeping genes was measured (proC for P. aeruginosa and 16s rRNA for S. aureus). Based on these tests, log reduction of experimental conditions was compared to identify time dependent and precise antimicrobial properties from wound dressing samples. These results showed antimicrobial properties of wound dressings diminished as incubation days are increased for both methods from day 1 PCR result of 4.31 ± 0.54 and day 1 plating result of 6.31 ± 3.04 to day 3 PCR result of 1.22 ± 0.97 and day 3 plating result of 5.89 ± 2.41. These results show that data from qRT-PCR generally produced lower standard deviation than that of culture methods, hence shown to be more precise. Complementary parallel analysis of samples using both methods better characterized antimicrobial properties of the tested samples.

ISOLATION, CHARACTERIZATION AND ANTIMYCOBACTERIAL POTENCY OF A FURAN DERIVATIVE FROM THE CHLOROFORM CRUDE EXTRACT OF Icacina trichantha oliv TUBER.

Spectroscopic analysis of a pure isolate (OAU 2, a furan derivative) by column chromatography from the chloroform crude extract of Icacina trichantha tuber was done using FT-IR, 1HNMR, 13CNMR, COSY and was established by literature as well as the investigation of antimycobacterial potency. This anitmycobacterial activity revealed that this isolate actually has activity against DR-TB Strain and H37RV Strain which are American type culture collection strain and multi-drug resistant strains of M. tuberculosis being the test organisms. Hence, confirming the folk believe of the use of I. trichantha tuber in the treatment of “serious cough”

Effect of chlorpyrifos-exposure on the expression levels of CYP genes in Daphnia magna and examination of a possibility that an up-regulated clan 3 CYP, CYP360A8, reacts with pesticides.

Daphnia magna is a test organism used for ecological risk assessments of pesticides, but little is known about the expression levels of cytochrome P450s (CYP)s and their changes after pesticide exposure in the less than 24-h-olds used for ecotoxicity tests. In this study, D. magna juveniles were exposed to 0.2 μg/L of chlorpyrifos under the conditions for acute immobilization test as specified by the OECD test guideline for 24 h, and then the gene expression was compared between the control and chlorpyrifos-exposure groups by RNA-sequencing analysis, with a focus on CYP genes. Among 38 CYP genes expressed in the control group, seven were significantly up-regulated while two were significantly down-regulated in the chlorpyrifos-exposure group. Although the sublethal concentration of chlorpyrifos did not change their expression levels so drastically (0.8 < fold change < 2.6), CY360A8 of D. magna (DmCYP360A8), which had been proposed to be responsible for metabolism of xenobiotics, was abundantly expressed in controls yet up-regulated by chlorpyrifos. Therefore, homology modeling of DmCYP360A8 was performed based on the amino acid sequence, and then molecular docking simulations with the insecticides that were indicated to be metabolized by CYPs in D. magna were conducted. The results indicated that DmCYP360A8 could contribute to the metabolism of diazinon and chlorfenapyr but not chlorpyrifos. These findings suggest that chlorpyrifos is probably detoxified by other CYP(s) including up-regulated and/or constitutively expressed one(s).

Bootstrapping for Estimating the Conservative Kill Ratio of the Surrogate to the Pathogen for Use in Thermal Process Validation at the Industrial Scale

A surrogate is commonly used for process validations. The industry often uses the target log cycle reduction for the test (LCRTest) microorganism (surrogate) to be equal to the desired log cycle reduction for the target (LCRTarget) microorganism (pathogen). When the surrogate is too conservative with far greater resistance than the pathogen, the food may be overprocessed with quality and cost consequences. In aseptic processing, the Institute for Thermal Processing Specialists recommends using relative resistance (DTarget)/(DTest) to calculate LCRTest (product of LCRTarget and relative resistance). This method uses the mean values of DTarget and DTest and does not consider the estimating variability. We defined kill ratio (KR) as the inverse of relative resistance.The industry uses an extremely conservative KR of 1 in the validation of food processes for low-moisture foods, which ensures an adequate reduction of LCRTest, but can result in quality degradation. This study suggests an approach based on bootstrap sampling to determine conservative KR, leading to practical recommendations considering experimental and biological variability in food matrices. Previously collected thermal inactivation kinetics data of Salmonella spp. (target organism) and Enterococcus faecium (test organism) in Non-Fat Dried Milk (NFDM) and Whole Milk Powder (WMP) at 85, 90, and 95°C were used to calculate the mean KR. Bootstrapping was performed on mean inactivation rates to get a distribution of 1000 bootstrap KR values for each of the treatments. Based on minimum temperatures used in the industrial process and acceptable level of risk (e.g., 1, 5, or 10% of samples that would not achieve LCRTest), a conservative KR value can be estimated. Consistently, KR increased with temperature and KR for WMP was higher than NFDM. Food industries may use this framework based on the minimum processing temperature and acceptable level of risk for process validations to minimize quality degradation.

Antimicrobial Activity of Jatropha Curcas Sap on Selected Microorganisms

Jatropha curcas sap is used for medicinal purposes.It has played a major role in the treatment of various diseases including bacterial and fungal infections.This study evaluated the antimicrobial activity of Jatropha curcas sap against selected microorganisms (Shigella spp, Staphylococcus aureus, Salmonella spp,Candida albicans and Trichophyton spp) using standard procedures.The qualitative phytochemical screening of the sap reveals the presence of saponins, alkaloids, flavonoids,tannins, carbohydrate, glycosides while Steroids was absent. It was observed that the test organisms were more susceptible at high concentration which is 100. The highest zone of inhibition for bacteria was observed on Staphylococcus aureus and the lowest zone of inhibition was on Salmonella sp. For fungi the highest zone of inhibition was on Candida albicans and the lowest zone of inhibition was on Trichophyton sp. There was no zone of inhibition for water which serves as negative control. But there was zone of inhibition for the positive controls which were Ciprofloxacin and Ketoconazole. Jatropha curcas sap is a potential antimicrobial substance, active against Gram negative and Gram-positive bacteria and some fungi. It is therefore a potential antimicrobial agent.

Experience in Assessing the Toxicity of Formation (Produced) Water of the LUKOIL-Ukhtaneftegaz RPC for the Environment

The chemical composition and toxicity for living organisms-aquatic organisms of reservoir (waste) and surface (for injection into reservoir) waters of production facilities of the LUKOIL-Ukhtaneftegaz RPC were studied. It has been established that highly mineralized formation waters have acute toxicity for daphnia, green unicellular algae and fish fry, which is eliminated by diluting the samples 2–100 times. Indicators of the Lethal Dilution Ratio of LDR50 and lethal concentrations of LC50 of the studied water samples were calculated for test organisms, which ranged from 10,780 to 27,910 mg/l, averaging 21,140 mg/l. It was concluded that the studied samples of formation water, which differ significantly (by 3–4 orders of magnitude) in a positive direction from the standard LC50 concentration of 10 mg/l, cannot be classified as substances that pose a hazard to the natural environment.

Nutritional Properties, Antioxidant and Antimicrobial Activity of Seed and Peel Extracts of Grapefruit (Citrus paradisi) on Some Selected Clinical Organisms

The need for new antimicrobial agent is linked with the emergence of strains that are restraint to most antibiotics and plants are safer alternative source of antimicrobials. This study aimed at determining the nutritional properties, phytochemical constituents, antioxidant and antimicrobial activity of seed and peel Citrus paradisi. The test organisms were obtained from a tertiary hospital were analyzed using conventional microbiological methods. The ethanol and aqueous extracts of C. paradisi was obtained using the rotary evaporator. Antimicrobial activity was determined using agar well diffusion method. Proximate composition of seed and peel of C. paradisi were moisture, protein, ash, fibre, lipid and carbohydrates. Qualitative phytochemical constituents revealed the presence of alkaloids, saponin, tannin and flavonoids, and Quantitative phytochemical constituents revealed 19.41 mgGallic acid equivalent/g and 8.07 mgGallic acid equivalent/g of total phenols of ethanolic and aqueous peel extracts respectively. The ethanolic extract of seed had phenolic content of 3.73 mgGAE/g. The ethanolic peel and aqueous seed extracts showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity of 35.32% and 25.32% respectively. The ethanolic seed extract of C. paradisi exhibited antimicrobial activity against all the bacterial test isolates at different concentrations. At 500mg/ml and 250mg/ml, P. aeruginosa showed the mean zone of inhibition of 18mm respectively. The largest mean zones of inhibition for S. aureus and E.coli were seen at 500mg/ml and 250mg/ml with 20mm and 27mm respectively. The ethanolic peel extract of C. paradisi exhibited antimicrobial activity at 500mg/ml against P. aeruginosa and S. aureus, with the largest zones of inhibition of 25mm and 20mm respectively. At 250mg/ml, E. coli, had the largest mean zone of inhibition of 25mm. No antimicrobial activity was observed for both ethanolic peel and seed extracts of C. paradisi against Aspergillus spp. The aqueous extract of the seed of Citrus paradisi at the different concentrations showed no antimicrobial activity against both the bacterial and fungal isolates. The aqueous extract of the peel had antimicrobial effect on P. aeruginosa at 125mg/ml with mean zone of inhibition of 15mm. At 500mg/ml S. aureus and E. coli exhibited zones of inhibtion of 15mm and 20mm respectively. No zone of inhibition was observed with Aspergillus spp. This investigation indicates the peel of C. paradisi has medicinal activity and holds the potential as therapeutic agent for treating microbial infections.

Synthesis and Characterization of 4-(1-(2H benzo[d][1,2,3]triazol-2-ylimino)ethyl)benzonitrile and amino acid alanine and its Metal Complexes

The biological actions of transition metal ion complexes with mixed ligands are very different. Amino acid and azomethine containing Schiff bases are very useful building blocks for ternary complexes. The interaction of two ligands 4-(1-(2H-benzo[d][1,2,3]triazol-2-ylimino)ethyl)benzonitrile as L1 and an amino acid alanine as L2, with newly synthesized cuprous chloride solution in a 1:1:1 molar ratio using standard reflux approach has been attempted to create unique metal(I) complexes. Elemental analysis, molecular weight, magnetic moment, thermal analysis and spectroscopic methods are used to characterize the produced ligand and metal(I) complexes. Bacillus subtilis, Escherichia coli and Candida albicans were used as test organisms in antibacterial tests of the produced compounds. Antibacterial and antifungal activity of the metal (I) complexes have been shown to be very high against ciprofloxacin, ketoconazole.