54 research outputs found

    Biofuel: Sources, Extraction and Determination

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    Algal Biomass and Biodiesel Production

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    The role of salt stress on laboratory cultivation of green macroalga Enteromorpha compressa and its antioxidant activity

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    تمت زراعة العشب البحري الاخضر انتيرومورفا كومبريسا (المثبت علي دعامته الصخرية الصغيرة) معمليا تحت الظروف الطبيعية لفصل الربيع من درجة حرارة و شدة اضاءه و توقيت ضضوي. و ذلك لدراسة مدي تحمل هذا العشب الاخضر و النامي طبيعيا في منطقة المد و الجزر، للاجهاد الملحي (تركيزات أقل و أكبر من تركيز ماء البحر). و لهذا تمت زراعتة معمليا و نقله بعد جمعه من بيئته و هو مثبت علي دعامتة الصخرية الصغيرة و في فصل الربيع (حيث يسود نموه في منطقة المد و الجزر) و أقلمته لمدة اسبوع علي النمو معمليا تحت نفس ظروف بيئته ثم نموه تحت ظروف اجهاد ملحي صناعي (ASW) و مقارنته بعينه ضابطه تنمو تحت ظروف ماء بحر طبيعي  (NSW) و باستخدام تهويه بمعدل ثابت خلال مده التجربة و تحت ظروف فصل الربيع الطبيعية من ضوء و درجة حرارة. تم تعيين معدل النمو للطحلب (ممثل بالمحتوي الصبغي الكلي للكلوروفيل و الكاروتينويدات) علي فترات منتظمة (كل 5 أيام) خلال مدة التجربة (25 يوما). تم عمل مستخلصات للطحلب النامي تحت ظروف الاجهاد الملحي المختلفة باستخدام مذيبات عضوية مختلفه القطبيه(petroleum ether, chloroform, ethyl acetate and  acetone)   و تعيين المحتوى الصبغي و مضادات الاكسده (مقارنه بمضاد الاكسده القياسي BHT). أظهرت النتائج وجود زياده في معدل النمو خاصة عند تركيزات 35, 53 g/L   و بمعدل أقل عند تركيز106 g/L  و ذلك خلال الخمسه عشر يوما الاولي للتجربة ثم بدأ بعدها تدهور ملحوظ و تدريجي للنمو نتيجة تأثير الاجهاد الملحي التراكمي علي عمليتي البناء الضوئي و التمثيل الغذائي. بالنسبة للنشاط المضاد للاكسده و الذي يعتمد علي التركيز، نوع المذيب العضوي للمستخلص و علي مدة التحضين ، فقد تم تعيينه بعد الخمسه عشر يوما الاولي للتجربة و في نهايتها (25 يوم) ، أظهر مستخلص الاسيتون أعلي نشاط مضاد للاكسدة تحت كل الظروف و التركيزات مقارنة بباقي المستخلصات و بمضاد الاكسدة القياسي BHT، و كان أكثرها نشاط هو أكبر تركيز للملوحة (106 g/L).Cultivation of the green seaweed Enteromorpha compressa was performed under natural laboratory spring environmental conditions of temperature, light intensity and photoperiod to study the salinity tolerance of this intertidal green macroalga. Cultivation was carried out under artificial seawater (ASW) of different concentrations (18, 35, 53 and 106 g/l sea salt) compared to the control using natural seawater (NSW). Growth rate and pigment content of the cultivated alga were recorded at regular intervals during the experimental duration. Antioxidant activity of the crude ethanolic extract and its fractions (petroleum ether, chloroform, ethyl acetate and acetone) was performed against DPPH radical scavenging assay and compared to the standard synthetic antioxidant butylated hydroxy-toluene (BHT). The finding showed that enhancement of algal growth rate under ASW concentrations of 35, 53 and to a lesser extent at 106 g/L during the first 15 days of cultivation were due to the increased pigment biosynthesis, photosynthetic and metabolic activities and followed by gradual retardation due to the impact of prolonged salt stress. Antioxidant activity of alga was found to be concentration, type of extract and incubation time dependent. Acetone fraction of all salt concentrations showed higher antioxidant activity compared to other fractions. Pronounced activity was recorded at higher seawater conc. (106g/l)

    Rice husk templated water treatment sludge as low cost dye and metal adsorbent

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    AbstractThe preparation of adsorbents at low cost as alternatives to the expensive ones in the treatment processes of water and wastewater is the interest of the researchers worldwide. Here, a novel cheap mesoporous adsorbent was prepared via the recycling of wastes namely water treatment sludge and rice husk (RH) as textural modifier. Surface area and pore dimensions were optimized against RH ratio. The mesoporous sludge was employed in adsorption of rosaniline dye, Pb2+, Ni2+ and chlorine from aqueous solutions under dynamic experimental conditions. It was found that the initial dye concentration and textural structure of the adsorbent played important roles in adsorption capacity. The reusability test shows the ease desorption of dye with slightly alkaline water (pH=8) indicating the stability and reusability of the ceramic adsorbent for several times. For metallic cations, the characteristics (ionic radius and ΔHhyd) of ions affect the adsorption affinity. Chlorine adsorption is controlled by the cation exchange capacity(CEC)

    Cytotoxic and antioxidant properties of active principals isolated from water hyacinth against four cancer cells lines

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    BACKGROUND: Eichhornia crassipes (Mart) solms is an invasive macrophyte causing serious problems to the network of irrigation and drainage canals in the Nile Delta region. The present study aim to evaluate the potential anticancer and antioxidant activities of Eichhornia crassipes crude extract and its pure compounds. METHODS: The macrophyte was collected from El-Zomor canal, River Nile (Egypt), cleaned, air dried, grinded then extracted with methanol (crude extract). The extract was fractionated using pre-coated silica gel plates (TLC F(254)) with hexane/ethyl acetate (8.5: 1.5 v/v) as mobile phase. Nine fractions were separated (A-I) then scratched, eluted with the same mobile phase, filtered and the separated fractions were determined and identified using spectroscopic methods (Mass spectrum (MS), Infra red (IR) and Proton H-Nuclear magnetic resonance (H-NMR). Both the crude extract and its nine identified compounds were tested for their antioxidant (using 2, 2 diphenyl-1-picrylhydrazyl (DPPH), 2, 2′- azino-bis {ethylbenzthiazoline-6-sulfonic acid (ABTS(.))} methods) and anticancer activity (using MCF-7, HeLa, Hep.G2 and EACC cell lines). RESULTS: The antioxidant and anticancer activities of the crude extract exhibited the highest effect while the compounds showed variable effects which depend on the type of compound and cancer cell line. The antioxidant activity of the crude extract exhibited the highest followed in descending order by compounds D, E, G and H respectively. Concerning the anticancer potency, the crude extract showed also the highest effect while the identified compounds (A, B, C, D, E, F, G, H and I) showed variable anticancer activities against the four different cell lines. In addition, Compound I exhibited the most potent anticancer activity against HepG2 cell line while compound D exhibited high anticancer activity against HeLa cells and EACC. The results revealed the presence of different compounds (Alkaloids and terpenoids) with variable antioxidant and anticancer activities which elicited an auto-augmentation in the crude extract leading to its greatest activities. The action of the identified anticancer compounds on DNA fragmentation was studied. CONCLUSION: The study illustrated the potential of Eichhornia as a valuable resource for natural compounds of desirable medicinal properties (e.g. antioxidants and anticancer)

    Antioxidant and cytotoxic activities of Artemisia monosperma L. and Tamarix aphylla L. essential oils

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    Essential (volatile) oil from leaves of Artemisia monosperma L. belonging to family Asteraceae, and aerial parts of Tamarix aphylla L. (Athel) belonging to family Tamaricaceae were collected from the desert of Ha'il region, northern region of Saudi Arabia, hydro distilled by Clevenger apparatus and analysed by means of GC-MS techniques. Antioxidant activities of essential oils of A. monosperma and T. aphylla compared with ascorbic acid and butylated hydroxytoluene (BHT) as reference antioxidant compound were determined by method of DPPH radical scavenging assay and ABTS assay. In vitro screening of potential cytotoxicity of essential oils was also evaluated against human promyelocytic leukaemia cell lines (HL60 and NB4). The GC/MS analysis of A. monosperma essential oil resulted in identification of 61 components predominated mainly by β-Pinene as principal component (29.87%) and T. aphylla resulted in identification of 37 components of essential oil predominated mainly by 6,10,14- trimethyl-2-pentadecanone (21.43%) as principal component. Antioxidant activity as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and 2,2 -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) increased with increasing essential oil concentrations of A. monosperma and T. aphylla (25, 50, 75, 100 and 200 μg mL-1). The most pronounced increases detected in the high concentrations of the two essential oils. Biologically, essential oil extracts exhibited cytotoxicity effects in dose dependent manner against human promyelocytic leukaemia cell lines (HL60 and NB4). In conclusion, A. monosperma and T. aphylla essential oils could be valuable source for cytotoxic agents with high safety and selective cytotoxicity profiles

    Enhancement the removal capacity of heavy metals from aqueous solution using different aquatic organisms

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    151-162The Eichhornia sp had high ability for bioremoval of Pb and Cd (97.15 and 97.48%) during 15 min with some ultrastructure changes of the leaf such as, ruptured or disappeared plasma membrane, swollen mitochondria and malformation chloroplast and some anatomical studies; thickness of upper epidermis and mesophyll decreased with presences number of raphide crystals in treated leaf but it not found in untreated plants. It was noticed that treated with Pb was more effect on histological leaf than treated with Cd. While, Gelidium pectinatum had highest efficiency for removal of Cd but during 0.5 hr. The bioremoval efficiency of lead by Gelidium pectinatum increased with Epichlorohydrin 1 from 28.84 to 90.18 % during 240 min contact time and from 77.34 in raw (untreated) algae to 99.58% in case of cadmium during the same contact time

    Allelopathic Effects of Water Hyacinth [Eichhornia crassipes]

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    Eichhornia crassipes (Mart) Solms is an invasive weed known to out-compete native plants and negatively affect microbes including phytoplankton. The spread and population density of E. crassipes will be favored by global warming. The aim here was to identify compounds that underlie the effects on microbes. The entire plant of E. crassipes was collected from El Zomor canal, River Nile (Egypt), washed clean, then air dried. Plant tissue was extracted three times with methanol and fractionated by thin layer chromatography (TLC). The crude methanolic extract and five fractions from TLC (A–E) were tested for antimicrobial (bacteria and fungal) and anti-algal activities (green microalgae and cyanobacteria) using paper disc diffusion bioassay. The crude extract as well as all five TLC fractions exhibited antibacterial activities against both the Gram positive bacteria; Bacillus subtilis and Streptococcus faecalis; and the Gram negative bacteria; Escherichia coli and Staphylococcus aureus. Growth of Aspergillus flavus and Aspergillus niger were not inhibited by either E. crassipes crude extract nor its five fractions. In contrast, Candida albicans (yeast) was inhibited by all. Some antialgal activity of the crude extract and its fractions was manifest against the green microalgae; Chlorella vulgaris and Dictyochloropsis splendida as well as the cyanobacteria; Spirulina platensis and Nostoc piscinale. High antialgal activity was only recorded against Chlorella vulgaris. Identifications of the active antimicrobial and antialgal compounds of the crude extract as well as the five TLC fractions were carried out using gas chromatography combined with mass spectroscopy. The analyses showed the presence of an alkaloid (fraction A) and four phthalate derivatives (Fractions B–E) that exhibited the antimicrobial and antialgal activities

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
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