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The toxicity and PAH of C. gariepinus (0.98±0.01g, n=480) to 1, 3, 6, 9, 12 and 0.0 ml/L of BLCO oil was determined and were exposed to 3 treatment sublethal concentrations (2.40, 1.20, 0.60 (corresponding to 1/16, 1/8 and 1/4 of 96h LC50) and 0.00 ml/L of WSF of BLCO in triplicate replications of 60 fish per treatment for 10 weeks. The 96h median lethal concentration of BLCO to the experimental fish fingerlings was 9.6 ml/L. The mean ∑ 16PAH gave 6% compared to 11% that of its mean 8PAH. Mean TEQ and MEQ in 8PAH both corresponded to 11%, however BaP-TEQ in BLCO ranged from 0% in Chry to 84% in DahA while BaP-MEQ ranged from 0% in Chry to 30% in DahA. The respective Benzo [a] Pyrene carcinogenic and mutagenic equivalents of Clarias gariepinus to BLCO was 2 and 9%. There was a significant difference (P

This study aimed to get an insight into the effects of household processing on the leaching behaviour of 137Cs and 40K from fresh, frozen and dried Boletus edulis (King Bolete) mushrooms. Three processes were investigated—blanching, blanching and pickling, and drying followed by grinding and soaking. The activity concentrations of 137Cs and 40K in the fresh unprocessed mushrooms were 270 Bq kg−1 dry biomass (27 Bq kg−1 whole weight) and 590 Bq kg−1 db (59 Bq kg−1 ww), respectively. Blanching of fresh mushrooms decreased 137Cs activity by 55%, and 40K activity by 34%, and blanching of deep-frozen mushrooms caused a reduction of 52% and 44% (db) (equivalent to whole weight reductions of 37% and 8.5%, and 67% and 22%, respectively). Blanching and pickling of fresh mushrooms decreased 137Cs activity by 83% and 40K activity by 87%, while blanching deep-frozen mushrooms resulted in decreases of 88% and 80% (db) (whole weight decreases of 77% and 81%, and by ~ 84% and 72%, respectively). This study confirms earlier reports that blanching of fresh or frozen mushrooms alone is not as efficient at removing 137Cs as blanching followed by pickling. The study also shows that the initial rate of fruiting body disintegration and pre-preparation (comparing fresh, deep-frozen, or dried and ground) can have an impact on the leaching rate of the water soluble fraction of metallic elements.

Sukun (Artocarpus altilis), the breadfruit, has been known to contain phytochemicals that have inhibitory activity against xanthine oxidase, however little is known about their efficacy in lowering uric acid levels. This study aims to determine the effect of water-soluble fraction of breadfruit leaf extract on blood uric acid levels in purine-rich food-induced mice. Twenty-five male mice received beef liver extract once daily for 7 days and were grouped into five. The first group receives only solvent as the normal control. At day 8, mice of first group were sacrificed for taking their blood and measuring its uric acid levels. As for the group 2, 3, and 4, in the period of day 8 to day 14, consecutively received sukun leaves extract at the dosage of 58.5, 117 and 234 mg/kg BW. Group 5 received allopurinol at the dose of 13 mg/kg BW as the positive control. At the day 15 all mice were sacrificed and their blood uric acid levels were determined. The results showed that the water fraction of sukun leaf extract significantly decreased blood uric acid levels of test mice. At the dose of 234 mg / kg BW the anti-hyperuricemic properties of the plant leaf extract equals the standard drug, the allopurinol.

Судак является одним из наиболее часто встречающихся и широко распространенных видов рыб на территории Калининградского региона. После разделки рыбы на филе как вид пищевых отходов образуется кожа. Цель исследования –изучить физико-химические свойства покровных тканей судака в различные периоды вылова и показать возможность их использования в качестве сырья для проведения высокотемпературного гидролиза. Определены физико-химические показатели в соответствии с ГОСТ 7636-85 «Рыба, морские млекопитающие, морские беспозвоночные и продукты их переработки. Методы анализа» с установлением массовых долей воды, белка, жира и золы. Оценка показателей проводилась у сырья, отобранного из объекта сентябрьского и ноябрьского вылова 2019 г. Гидролиз выполнен с использованием автоклавирования при температуре 130 °С под давлением 0,25 МПа в течение 60 мин при скорости вращения мешалки 60 об/мин. В результате температурного воздействия на костную, хрящевую ткани с прирезями мышц получены три фракции: верхняя (водорастворимая), нижняя (осадочная) и жировая (следы). Проведена оценка их физико-химического состава с определением массовой доли воды, белка, жира, золы, а также органолептическая оценка полученных фракций до высушивания, измельчения и после них. В связи с низким содержанием липидов в исходном сырье последняя фракция (следы) в ходе термолиза не была образована, и, соответственно, оценка ее физико-химического состава не проводилась. Перспективной является возможность получения и использования композиций из покровных тканей судака в качестве обогащающих добавок в технологии функциональных продуктов питания, так как гидролизованная кожа рыб – источник легкоусвояемого белка и его структурных компонентов, а также минеральных веществ и некоторых гликозаминогликанов.

This study evaluated the Hematotoxic effect of water soluble fraction (WSF) of Bonny Light Crude Oil (BLCO) in Wistar Albino rats. After preparation of the WSF and a range finding test, the Wistar albino rats were administered three concentrations (25%, 50% and 100%) of WSF of BLCO for 30 and 60days. Data from the study showed that there was a significant decrease (p≤0.05) in PCV values (30.2% in the control group to 17.2% in the 100% group), Hb levels decreased significantly from 9.25 g/dl in the control group to 5.27 g/dl in the 100% group. WBC count decreased significantly from 2932 mm3 in the control group to 136 mm3 in the 100% group and finally RBC count decreased significantly from 241.8E4 mm3 to 567 mm3 with increasing concentrations in the treatment groups after 60days administration. These results suggest that the oral consumption of the WSF of BLCO led to an onset of anaemia which indicates the presence of less than normal concentrations of PCV, Hb and RBC.

This study evaluated the Nephrotoxic effect of water soluble fraction (WSF) of Bonny Light Crude Oil (BLCO). After preparation of the WSF and a range finding test, the Wistar albino rats were administered three concentrations (25%, 50% and 100%) of WSF of BLCO for 30 and 60days. Data from the study showed that Urea concentration increased significantly (p≤0.05) with increasing dose of BLCO ranging from 14.71 mg/dl in the control to 35.28 mg/dl in the 100% group after 30days and 14.28 mg/dl in the control to 41.08mg/dl in the 100% group after 60days, Creatinine concentration increased significantly (p≤0.05) from 0.22 mg/dl in the control to 0.82mg/dl in the 100% group after 60 days administration while electrolyte (Na, K, Cl) concentration increased significantly (p≤0.05) with increasing dose of BLCO after 60days administration. Histopathological examination of the kidney was characterized by partial partitioning of the glomerular tufts, obliteration of the Bowman’s capsule and distortion of the renal tubules. The findings in this research suggest that WSF of BLCO induced nephrotoxicity.

The cortex root of Paeonia ostii, is used as a traditional Chinese medicine for treating female diseases. Phytochemical investigation of the water-soluble fraction of the plant led to the isolation of two new acetoisovanillone glycosides: acetoisovanillone-3-O-β-D-glucopyranoside (1) and 2-hydroxy-acetoisovanillone-3-O-β-D-glucopyranoside (2). Their structures were elucidated by extensive spectroscopic methods.

The effects of different concentrations of water-soluble fraction of crude oil (WSFO) from the Zhanazhol oil field (Aktobe region, Kazakhstan) and compared to o-xylene, prevalent in this oil, on growth and development of marsh frog (Rana ridibunda) were assessed. In subchronic experiments (7 d), a dose-related increase in mortality and incidence of deformities in embryos were observed. In chronic experiments (60 d; starting from the Gosner stage 26), a dose-dependent decrease in body weight, size and developmental delay by 3-4 stages were also detected. In addition, the content of lipid hyperoxide (LHO) and malondialdehyde (MDA), as well as activities of superoxide dismutase (SOD) and catalase (CAT) enzymes in liver of the tadpoles were determined at the end of chronic experiment. Exposure to 0.5 mg/L or 1.5 mg/L WSFO elevated the content of LHO by 76% and 86%, and MDA by 47% and 58% but decreased SOD activity by 26% and 49%, and CAT by 35% and 46%, respectively. A less pronounced adverse effect was found after chronic exposure to the same concentrations of o-xylene. In tadpole liver exposed to o-xylene levels of LHO was increased by 40% and 51%, MDA by 11% and 29%, while the activity of SOD was lowered by 18% and 41%, and CAT - by 13% and 37% in the 0.5 mg/L and 1.5 mg/L treatment groups, respectively. Data demonstrated the embryotoxic and teratogenic effects attributed to WSFO and o-xylene exposure which may involve oxidative stress mechanisms.

Two new lignans mubezhisol (1) and mubezhisal (2), together with twenty six known compounds (3–28) were isolated from water-soluble fraction from the semens of Momordica cochinchinensis. In the sub...

Background The application of chemical dispersants is a common remediation strategy when accidental oil spills occur in aquatic environments. Breaking down the oil slick into small droplets, dispersants facilitate the increase of particulate and dissolved oil compounds, enhancing the bioavailability of toxic oil constituents. The aim of the present work was to explore the effects of water accommodated fractions (WAF) of a naphthenic North Sea crude oil produced with and without the addition of the chemical dispersant FINASOL OSR 52 to adult zebrafish exposed for 3 and 21 d. Fish were exposed to environmentally relevant concentrations of 5% and 25% WAFOIL (1:200) and to 5% WAFOIL+D (dispersant–oil ratio 1:10) in a semi-static exposure setup. Results The chemically dispersed WAF presented a 20-fold increase of target polycyclic aromatic hydrocarbons (PAHs) in the water phase compared to the corresponding treatment without dispersant and was the only treatment resulting in markedly bioaccumulation of PAHs in carcass after 21 d compared to the control. Furthermore, only 5% WAFOIL+D caused fish mortality. In general, the undispersed oil treatments did not lead to significant effects compared to control, while the dispersed oil induced significant alterations at gene transcription and enzyme activity levels. Significant up-regulation of biotransformation and oxidative stress response genes (cyp1a, gstp1, sod1 and gpx1a) was recorded in the livers. For the same group, a significant increment in EROD activity was detected in liver along with significant increased GST and CAT activities in gills. The addition of the chemical dispersant also reduced brain AChE activity and showed a potential genotoxic effect as indicated by the increased frequency of micronuclei in erythrocytes after 21 d of exposure. Conclusions The results demonstrate that the addition of chemical dispersants accentuates the effect of toxic compounds present in oil as it increases PAH bioavailability resulting in diverse alterations on different levels of biological organization in zebrafish. Furthermore, the study emphasizes the importance to combine multilevel endpoints for a reliable risk assessment due to high variable biomarker responses. The present results of dispersant impact on oil toxicity can support decision making for oil spill response strategies.

Humic acids are a heterogeneous mixture of organic compounds that are naturally found in water and soil. In recent years, there has been a growing interest in the application of green fertilizers containing humic acids in agricultural activities. Water-soluble fraction of humic acid (WSHA) can be released from these fertilizers and subsequently interact with metallic materials (e.g. steel) located in soils and waters. WSHA were leached from an aqueous suspension of humic acids isolated from South Moravian lignite. Corrosion tests were performed on a low-carbon steel using a potentiodynamic polarization test and electrochemical impedance spectrometry. Results suggest that corrosion was initially promoted due to the formation of complex compounds of water-soluble humic acids with released iron ions. After a long time, a positive effect of WSHA was observed as the corrosion resistance of low-carbon steel increased.

Cereal derived arabinoxylans (AXs) are non-starch polysaccharides that have immunomodulatory activities. These activities are thought to be related to the low molecular weight fractions of AXs. Wheat and wheat byproducts are rich in AXs, however, the water extractable fraction of AXs in wheat products is low. Water extraction of AXs can be improved by extrusion processing, which increases the extractability of the water soluble fraction. The aim of this study was to determine the extractability and molecular weight of the water soluble fraction of AXs from wheat endosperm after extrusion at screw speeds of 80 and 160 rpm. Extrusion processing significantly (P < 0.05) increased the water extractability of AXs in a screw-speed dependent manner (13.07 ± 0.12% at 80 rpm and 15.45 ± 0.16% at 160 rpm compared to 8.95 ± 0.10% in the non-extruded control) due to a significant increase (P < 0.05) in low molecular weight fractions of AXs in extruded samples.

Shelf life of pearl millet flour is very short because of rapid development of rancidity. This investigation was carried out in view of generating breeding material for development of low rancid pearl millet hybrids/varieties. Flour of twenty-one genotypes; seven hybrids, seven CMS lines, five inbreds and two composites stored in covered aluminium boxes at 37 °C for 30 days along with respective fresh flour was analysed for shelf life indicators/determinants. Crude fat content and fat acidity (FA) of fresh flour of the genotypes varied from 3.8 to 7.2% and 11 to 75 mg KOH/100 g d.m., respectively. FA in stored flour ranged between 180 and 330 mg KOH/100 g d.m. After storage, magnitude of decrease in pH of water extract of flour of the genotypes varied from 0.15 to 0.44. Activity of peroxidase (POX) varied from 378 to 588 units in control flour and irrespective of the genotypes decreased upon storage. Increase in FA (difference between FA of fresh and stored flour) rather total build up of FA was positively associated with crude fat content (r = 0.440*) indicated comparatively more prominent role of lipolytic enzymes. Chemical changes taking place in water soluble fraction of flour were independent of fat content as no correlation was discerned between fat content and decrease in pH. Among the hybrids, HHB 197 had lowest crude fat content (4.7%), lowest total build up FA (212 mg KOH/100 g d.m.), slowest increase in FA (191 mg KOH/100 g d.m.), least decrease in pH (0.31) of water soluble fraction flour during storage and lowest activity of POX in fresh flour (377 units/g d.m). Among all the tested CMS lines, inbreds and composites, HBL 11 showed pattern of quantitative changes in FA, pH and POX activity similar to the hybrid HHB 197 and was identified a promising inbred for developing low-rancid pearl millet variety or hybrid.

Defatted heterotrophic microalgae (Aurantiochytrium limacinum SR21) was treated with high temperature water (175-350°C, 10-90min) to obtain nitrogen and phosphorous nutrients as a water soluble fraction (WS). Yields of nitrogen and phosphorous recovered in WS varied from 38 to 100% and from 57 to 99%, respectively. Maximum yields of nitrogen containing compounds in WS were proteins (43%), amino acids (12%) and ammonia (60%) at treatment temperatures of 175, 250 and 350°C, respectively. Maximum yield of phosphorous in WS was 99% at a treatment temperature of 250°C. Cultivation experiments of microalgae (A. limacinum SR21) using WS obtained at 200 and 250°C showed positive growth. Water soluble fractions from hydrothermal treatment of defatted microalgae are effective nitrogen and phosphorous nutrient sources for microalgae cultivation.

Method of allocation and analysis of mobile forms of chemical elements in soil are considered. Chemical characteristics of the extracted liquid phase of the soil reflect its water-soluble part properties. Two reference soil profiles on glaciolacustrine clays (soddy-eluvial-metamorphic soil) and sands (soddy podzol) were investigated on the Russian Plain. The comparison of the data obtained with the results of analysis for the whole soil allows assessment of a share of highly mobile and less mobile forms of chemical compounds. The behavior of macro- and microelements was studied in soils and their liquid phase. Mobile forms of chemical elements play the important role as the basis for the development of a model describing their migration on soil profile, used in prospecting geochemistry and in environmental geochemistry.

The importance of interindividual variability in environmental responses has been little studied, although the available information suggests that, e.g., changes in environmental temperature may be associated with changes in variability. We studied, if exposure to water-soluble fraction (WSF) of crude oil can be associated with changes in interindividual variability in phenotype in Daphnia magna, which reproduces parthenogenetically. By using these clonal organisms, we could exclude the possibility that the observed changes were caused by genetic variability. The results show that the variability of oxygen consumption rate decreased in 48 h 30% WSF-exposed animals as compared to 10% WSF-exposed or control animals without a change in the mean of oxygen consumption rate. The clonal Daphnia magna could also be used to study transgenerational effects without genetic contribution, as the different generations are genetically identical. We observed that the oxygen consumption rates in F1 and F2 generations of unexposed and 10% WSF-exposed Daphnia had decreased from parental F0 generation and were also lower than in offspring of 30% WSF-exposed specimens. The studies did not aim at environmental realism but were designed to show the possibility of variability changes without changes in the mean value of a parameter, and transgenerational effects as a result of environmental contamination.

Background: Ocimum sanctum is a well reputed medicinal herb being used in the treatment of various ailments in this Indo Pak Subcontinents since ancient time.Methods: In this study the Antihypertensive effects of water extract of Ocimum sanctum and Water soluble fraction of methanol extract of Ocimum sanctum were tried for its antihypertensive effects on albino rats. Extracts were administered via vein and BP was recorded in the carotid artery by direct invasive method.Result: Normal blood pressure was 81/71 mm of Hg (mean blood pressure was 75 mm of Hg. Water extract of Ocimum sanctum has got significant antihypertensive effect (19-30 %). Water soluble fraction of methanol extract of Ocimum sanctum has also got significant antihypertensive effect (15-27 %).Bangladesh Journal of Medical Science Vol.15(3) 2016 p.357-361

As an option for utilizing glycerol in stationary applications (e.g. combustion in boilers or furnaces), fuel mixtures prepared by the current approach of mixing crude glycerol, the whole bio-oil, and/or biochar have limitations of low glycerol blending ratio, high demand of methanol, and still in acidic nature. This study aims to overcome these limitations via preparing fuels from crude glycerol, the bio-oil–water-soluble fraction (WSF), and/or biochar. Three types of formulated crude glycerols (FCGs) were used in the experimental program: FCG1 and FCG3 representing crude glycerol without purification and FCG2 representing crude glycerol with an acidification process. The FCGs were mixed with the bio-oil–WSF obtained at the water/bio-oil ratio of 0.5 for preparing fuel mixtures, achieving remarkably high glycerol blending levels (50–70% for FCG1 and FCG3, while completely miscible for FCG2) without methanol addition. Moreover, the FCG/WSF blends have considerably lower acidities and water contents and hi...

Volcanic ash contains thallium (Tl), which is highly toxic to the biosphere. The aim of this study was to determine the Tl concentration in fractions of volcanic ash samples originating from the Eyjafjallajökull volcano. A sequential extraction scheme allowed for a study of element migration in the environment. Differential pulse anodic stripping voltammetry using a flow measuring system was selected as the analytical method to determine Tl content. The highest average content of Tl in volcanic ash was determined in the fraction entrapped in the aluminosilicate matrix (0.329 µg g(-1)), followed by the oxidizable fraction (0.173 µg g(-1)). The lowest content of Tl was found in the water soluble fraction (0.001 µg g(-1)); however, this fraction is important due to the fact that Tl redistribution among all the fractions occurs through the aqueous phase.

Using isotopic ratio mass spectrometry (IRMS) measurements, this study analyzed samples of saffron originating from two distinct geographical regions. We then used the results to distinguish saffron of the two considered origins. δ13C data related to the crocin fractions in 48 saffron samples from Western Macedonia (Greece) and 48 samples from Khorasan Province (Iran) were correlated to an index derived from triacylglycerols. Isotopic data could clearly differentiate between samples from the two areas. The isotopic measurements were -28.3 to -26.9 for Greek samples, and -26.1 to -24.5 for Iranian samples. Another index, derived from a gas-chromatographic analysis of the triacylglycerols, successfully determined that the range of isotopic values that characterized Greek samples was 52% larger than the range that characterized Iranian samples. The application of statistical evaluations permitted us to identify the two groups of saffron with confidence and to accurately identify the site of origin of a saffron sample.

Here, we investigated that the mechanocatalytic depolymerization of cellulose in the presence of Aquivion, a sulfonated perfluorinated ionomer. Under optimized conditions, yields of water soluble sugars of 90-97% were obtained using Aquivion PW98 and PW66, respectively, as a solid acid catalyst. The detailed characterization of the water soluble fraction revealed (i) the selective formation of oligosaccharides with a DP up to 11 and (ii) that depolymerization and reversion reactions concomitantly occurred during the mechanocatalytic process, although the first largely predominated. More importantly, we discussed on the critical role of water contained in Aquivion and cellulose on the efficiency of the mechanocatalytic process.

The amount of the soluble fraction of trace elements released from inhaled particulate matter seems to be one of the key factors of the toxicity of these particles. This study reports the concentrations of PM10 and trace elements in total and water-soluble fractions (bioavailable form). Weekly samples were collected at two rural sites in Upper Silesia, Poland. Measurements were carried out from April to August 2013, divided between heating and non-heating sessions. During heating sessions, the concentrations of PM10 in selected sites varied in the range of 32.88–48.70 μg m−3, while for the non-heating sessions the range was 16.14–27.89 μg m−3. Selected PM10 samples (characteristic for both sessions) were determined by means of total and water-soluble content of eight trace elements. The elements are characteristic of carcinogenic (As, Cr, Cd and Ni), probably carcinogenic (Co and Pb) and toxic (Mn and Sb) groups. The analyses of the mineralized samples as well as the water-soluble fractions were carried out by ICP-MS method using a Varian 810 MS. The total concentration of carcinogenic Cd, Cr and Ni during non-heating sessions was 2.81, 7.97 and 4.82 ng m−3, respectively. While during heating sessions the total content was twice as high. Similar relation was observed for the concentration of PM10. The concentration of the soluble fraction of these elements in the atmospheric air in heating sessions was 1.62, 0.75, 2.20, 1.79, 1.85 ng m−3 for As, Cr, Pb, Mn, Sb, respectively and remained almost the same as in non-heating sessions. Lower levels of Ni and Cd (0.15 and 0.11 ng m−3) were determined during heating sessions. The obtained data indicate that during heating periods these elements are probable present mainly in other fractions with lower mobility, so less harmful to human health.

This study determines mineralogical association of trace elements in the ash core samples and provides insight into various factors that promote their mobility and eventual release into surface and groundwater systems. Fly ash from a power station ash dump in Mpumalanga Province (South Africa) was characterized using X-ray diffraction and X-ray fluorescence. A five-step sequential extraction procedure was used to determined mineralogical association of elements as a function of depth in the ash dump. The dry disposed ash cores are sialic in chemical composition. The mineral peak height as revealed by X-ray diffraction analysis showed variations due to heterogeneity in the ash dump and in homogenous continuous brine irrigation. The sequential extraction results showed that some trace elements are moving in a leaching pathway through the fly ash in the water soluble fraction. Toxic analytes are present in water soluble, exchangeable, and carbonate fractions. Observed Pb concentration maxima in the carbonate...

Steam explosion of oil palm frond has been carried out under different temperatures between 180 and 210°C for 4 min (severity of 2.96-3.84) after impregnation of the frond chips with water or KOH solution. The effects of impregnation and steam explosion conditions of oil palm fronds on the water soluble fraction and insoluble fraction were investigated. The maximum yield of hemicelluloses in water soluble fractions recovered was 23.49% and 25.33% for water and KOH impregnation, treated with steam explosion at temperature of 210°C (severity of 3.84) with a fractionation efficiency of 77.30% and 83.32%, respectively. Under this condition, the water insoluble fractions contained celluloses at 60.83% and 64.80% for water and KOH impregnation, respectively. The steam explosion temperature of 210°C for 4 min (logR(o) 3.84) was found to be the best condition in the extraction of hemicelluloses from OPF for both types of impregnation.

Three hydrocarbonoclastic bacteria isolated from crude oil-impacted mesotidal waters of the Niger Delta area of Nigeria, and identified, by 16S rRNA sequencing, as Vibrio fluvialis OWPB63, Serratia sp. MWPB18 and Pseudomonas fluorescens OWPB17 demonstrated commendable protease production ability in skimmed milk-minimal medium. Protease biosynthesis commenced in all three bacteria before the first 2 h of fermentation with peak productivities of 4.12, 0.73 and 1.12 μg/mL/h reached at 12, 36 and 48 h for Vibrio fluvialis, Serratia sp. and Pseudomonas fluorescens respectively. Activities of the enzymes assessed with azocasein as standard substrate were respectively 116.61, 174.56 and 145.84μg/mL/min. Median inhibition concentration (IC50) for Vibrio fluvialis enzyme biosynthesis, significantly (PRead Complete Article at ijSciences: V62017071344 AND DOI: http://dx.doi.org/10.18483/ijSci.1344

Acute toxicity of water soluble fraction (WSF) of diesel fuel was assessed by evaluating its effects on growth of two marine microalgae, Isochrysis and Chaetoceros. Pure cultures of each of the two microalgae were exposed to concentrations of 0% (controls), 5%, 10%, 15% and 20% of diesel WSF (in triplicates) and allowed to grow for 96 hours. Cell density was determined in each of the culture vessels every 24 hour. Cell density growth rate in every treatment, percentage growth inhibition by various concentrations and IC50 of diesel WSF on the two microalgae were determined following standard methods. While control cultures recorded exponential growth within 96 hour, the four WSF concentrations resulted in inhibition of cell growth of the two microalgae species every 24 hour. Cell growth inhibition effect increased significantly (p0.05). Ecological implications of the growth inhibition effects of diesel WSF microalgae were discussed.Key Words: Cell density, water soluble fraction (WSF), concentration, growth inhibition, 96 hour IC50, Isochrysis, Chaetoceros