MOSP - Macao Scientific Publishers

Research Article

Identification of Thiobacillus thiooxidans CGMCC 10329 and fundamental application in bioleaching as part of a synergic bacterial consortium

Hongfei Zhu* and Xuesong Zhao

Abstract: Bioleaching has become increasingly important in commercial gold extraction because of its economic benefits. Thiobacillus thiooxidans (also known as Acidithiobacillus thiooxidans) is an important participant in synergic bioleaching processes. In this study, a novel strain was isolated from an underground coal mine, identified and named Thiobacillus thiooxidans CGMCC 10329. A consortium of microorganisms including T. ferrooxidans DSM14882, Leptospirillum ferrooxidans CCTCC AB207038 and T. thiooxidans CGMCC 10329 was used to leach four gold ores and four sulfur-containing coal samples; we then determined gold recovery rates and removal rates of elements. The content that may be harmful to the environment, such as sulfur and arsenic contained in the ores, was investigated. The synergic leaching results indicated that the maximum deprivation rates of carbon, sulfur and arsenic were respectively 59.91%, 67.21%, and almost 100%. Bioleaching pretreatment markedly improved the gold recovery rate by 10.7% to 20% in subsequent cyanidation, compared with traditional extraction operations. The average sulfur removal rate by synergic leaching of the four coal samples was 35.4%. This synergic leaching method, to some extent, broadens gold ore resources and benefits the environment by reducing the impact of coal burning. Keywords: Thiobacillus thiooxidans; synergy; bioleaching; recovery rate; sulfur; deprivation[...] Read More.

Keywords: Thiobacillus thiooxidans; synergy; bioleaching; recovery rate; sulfur; deprivation

2021, 20(1), 1-6;

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Research Article

Assessment of Paramecium tetraurelia growth in a new synthetic culture medium

Full Length Research Paper

Abstract: For using an organism for ecotoxicological studies, it is important to understand its model of growth under some physicochemical parameters that influence with a direct manner its development. The knowledge of the optimal parameters for the paramecia development leads to realize a model of growth with clear stages. For that, we tried to study the influence of temperature, pH, nutrient density in the culture medium and pollution on the growth of Paramecium tetraurelia. Obtained results showed that paramecia prefer definite conditions. However, the growth was better in temperatures included between 25 and 30°C, with preference to increased temperatures and a slightly acidic pH. The culture medium was prepared from the mixture of several vegetables which the rates were studied depending to the growth. The combined effects of azoxystrobin and cyproconazole on the growth kinetics were studied. Results showed that treatment affected the population growth, the generation time and the velocity of generation.[...] Read More.

Keywords: Paramecium tetraurelia, growth kinetics, physicochemical parameters, azoxystrobin, cyproconazole.

2021, 20(1), 1-6;

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Research Article

Use of herbal extract for quantitative estimation of the antifouling activity in marine paint

A. M. Chandak*, Shastri P. N. and Gogte B. B.

Abstract: Biofouling and biofilm formations are of great concern to many modern industries, including marine, food, water, mining and medical field. The shipping industry has serious problems with biofouling (complex communities of marine organisms) on most surfaces submerged in seawater. This leads to problems such as increasing water resistance, fuel consumption and microbial corrosion of metal surfaces. The primary fouling agents on aquatic surfaces exposed to light happen to be algae and diatoms, whereas fungi and bacteria follow the trend, forming a biofilm on the surface. This further attracts the crustaceans and molluscs, which are responsible for macro-fouling. Various components such as tin, arsenic, mercury, lead and copper are used as the biocides. These components are polluting the environment affecting the marine life. The paper contents the use of herbal extract as the antifouling agent and approach for quantitative estimation of the antifouling activity of the Curcuma longa extract as compare to that of tin.[...] Read More.

Keywords: Antifouling, Curcuma longa, leaching, paint, Gleocapsa.

2021, 20(1), 1-6;

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Research Article

A study of purified and characterized novel glucose oxidase-like melanoidin to decolorize wastewater

Chin-Fa Hwang, Ying-Shu Jiang, Shyang-Chwen Sheu, Pao-Chuan Hsieh and Jia-Hsin Guo*

Abstract: A novel melanoidin decolorizing enzyme (MDE) produced by Geotrichum sp. No. 56, which exhibits decolorization activity against synthetic melanoidin and molasses containing wastewater, was purified and characterized. The purification process was performed using ammonium sulfate fractionation, DEAE-Cellulose and Sephadex G-150 column chromatography. The melanoidin decolorization activity of the MDE was improved up to 7.3 U mg-1, the equivalent to 8.3-fold increase from the initial protein preparation, with an overall yield of 9.1%. The results of gel filtration and SDS-PAGE revealed that the purified MDE was a dimmer with 127.5 kDa, and both subunits were alike with 63.5 kDa each. The optimum pH and temperature for the purified MDE were 6.5 and 45°C, respectively. The MDE activity was highly specific for -D-glucose, but completely inhibited by cysteine, iodoacetic acid, 2-mercaptoethanol, gluconic acid, HgCl2 or AgNO3. The MDE also decolorized the spent broth of monosodium glutamate fermentation. The Geotrichum sp. No. 56 producing MDE, which shares various characteristics with glucose oxidase (GOx), could be useful for decolorizing fermented wastewater.[...] Read More.

Keywords: Decolorization, Geotrichum sp., glucose oxidase, melanoidin, molasses wastewater.

2021, 20(1), 1-6;

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Research Article

Effects of intraperitoneal administration of GNPs in blood and tissues of rats in vivo

Mohamed Anwar K. Abdelhalim*, Mohammed S. Al-Ayed and Sherif A. Abdelmottaleb Moussa

Abstract: Nanoparticles (NPs) can potentially cause adverse effects on organ, tissue, cellular, subcellular, and protein levels due to their unusual physicochemical properties. Advances in nanotechnology have identified promising candidates for many biological and biomedical applications. Gold nanoparticles (GNPs) are being increasingly exploited for medical uses and other industrial applications. The aim of the present study was to elucidate the response of heavy elements levels to intraperitoneal administration of different GNPs into rats for period of 3 days in vivo. The experimental rats were divided into normal and 3 groups (G1A, G2A and G3A; G1: 20 nm; G2: 10 nm; G3: 50 nm; A: it means infusion of 0.05 ml of GNPs for 3 days). To investigate the role of GNP size on heavy elements [cadmium (Cd), nickel (Ni), lead (Pb) and cobalt (Co)] levels in blood and several tissues of rats, 50 µl daily dose of 10, 20 and 50 nm GNPs was intraperitonealy injected into rats for 3 days. Cd, Ni and Pb concentrations significantly increased in blood and all tissues of rats compared with the normal. Different changes were observed with Co concentrations in blood and several tissues of rats. Co concentrations significantly increased with 20 nm GNPs in blood and kidney tissue of rats compared with the normal while it significantly decreased in heart, lung and liver tissues of rats. 10, 20 and 50 nm GNPs may be an effective inducer of oxidative stress which was evident by the fact that they caused significant increase in Cd, Ni and Pb concentrations in blood and all tissues of rats compared with the normal. This study suggests that GNPs may interact with proteins and enzymes of the rats interfering with the antioxidant defense mechanism and leading to reactive oxygen species (ROS) generation, which in turn may imitate an inflammatory response and heavy element levels destruction. Exposure to intraperitoneal administration of GNPs is a potential source of oxidative stress toxicity in rats.[...] Read More.

Keywords: Gold nanoparticles, size, severaltissues, blood, heavy elements, toxicity, rats.

2021, 20(1), 1-6;

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Research Article

Evaluation of the biodegradability of starch based plastic polymer by some isolated composted soil fungi

Neveen S. Geweely* and Salama A. Ouf

Abstract: Fourteen fungal species (Alternaria alternata, Aspergillus candidus, Aspergillus flavus, Aspergillus niger, Aspergillus ochrochus, Botrytis cinerea, Chaetomium globosum, Fusarium moniliforme, Fusarium oxysporum, Fusarium solani, Penicillium chrysogenum, Penicillium funiculosm, Penicillium italicum and Phanerochaete chrysosporium) belonging to Ascomycete, Basidiomycete and Deuteromycete groups were isolated from composted soil in Egypt. The ability of laser induced plasma as a new technique to enhance fungal degradation efficiency of starch based plastic polymer was tested. The maximum significant plastic degradation activities for all isolated fungal species were showed after the lowest exposure time (5 min) to laser induced plasma. The highest efficient fungal degraded starch based plastic polymer was A. niger, where the initial appearance of clear zone was recorded only after two days accompanied with the highest significant amylotic activities. The evaluation of changes in starch based plastic polymer degraded by A. niger compared with uninoculated and non plasma treated A. niger degraded starch based plastic polymer was observed by scanning electron microscope (SEM). The maximum degradation efficiency accompanied with the highest loss of tensile strength (90 and 80.7%, respectively) was observed in the plasma treated A. niger degrading starch polymer. Four low molecular weight sugars were detected by HPLC in plasma and non plasma treated A. niger degrading plastic polymer.[...] Read More.

Keywords: Fungi, plastic, degradation, laser.

2021, 20(1), 1-6;

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Research Article

Isolation and characterization of bacteria from Melaka rubber estate agricultural soil to utilize 2,2-DCP as only carbon source

Wen-Yong Wong and Fahrul Huyop*

Abstract: Industrial chemicals and pesticides from agricultural activities cause a considerable threat to the environment. 2,2-dichloropropionate (2,2-DCP) is a synthetic halogenated compound used as herbicide. High concentration of 2,2-DCP is toxic if released to the environment and may pollute the soil and ground water source. Using current enrichment technique it was expected to isolate a new bacteria species able to degrade -halocarboxylic acid. Strain Wy1 isolated from soil in Melaka rubber estate was able to utilize 30 mM 2,2-DCP as the sole source of carbon and energy with maximum chloride ion released of 0.27 mmol/L in the liquid growth medium. The biochemical test and 16S rRNA analysis suggested that the bacterial identity was from the genus Labrys sp., and therefore it was designated as Labrys sp. strain Wy1. The cells doubling time in 30 mM 2,2-DCP liquid minimal medium was 33.44 h. Cell growth was inhibited when grown in liquid minimal medium above 30 mM 2,2-DCP due to the toxicity of 2,2-DCP to the cells. This is the first reported case that the genus Labrys sp. is able to degrade 2,2-DCP.[...] Read More.

Keywords: 2,2-dichloropropionate, dehalogenase, soil bacteria, Labrys sp.

2021, 20(1), 1-6;

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Research Article

Investigation of the occurrence of Eimeria species in native chickens of Shiraz, Iran

Full Length Research Paper

Abstract: The present study was conducted to investigate the prevalence of Eimeria species in native chickens reared under semi-scavenging system and were allowed to scavenge in the yard, in crop fields near water reservoirs. We studied 200 scavenging native chickens in villages around Shiraz City in Southwest Iran. These chickens had no history of vaccination against coccidiosis and had never been given coccidiostat drugs. The chickens were submitted for post-mortem and parasitological examinations. All the villages had chickens that were positive for different Eimeria spp. From a total of 200 native chickens examined, 128 (64%) were infected with coccidiosis. Eimeria tenella was the most prevalent species (24%) followed by Eimeria acervulina (18%), Eimeria necatrix (12%), and Eimeria maxima (10%). Prevalences varied by management and did not vary by flock size.[...] Read More.

Keywords: Eimeria, native chickens, prevalence, Shiraz, Iran.

2021, 20(1), 1-6;

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Review

Significance and use of walnut, Juglans regia Linn: A review

Nael Abu Taha and Mohammed A. Al-wadaan

Abstract: Juglans regia Linn is a medicinal plant that has been widely used in traditional medicine for a wide array of ailments that include helminthiasis, diarrhea, sinusitis, stomachache, arthritis, asthma, eczema, scrofula, skin disorders, and various endocrine diseases such as diabetes mellitus, anorexia, thyroid dysfunctions, cancer and infectious diseases. The present review, attempts to provide comprehensive information on the ethnobotanical use, pharmacology, nutritional value, preclinical and clinical studies, toxicity, other uses and current research prospects of the Juglans regia L. Currently, there is a renewed interest in walnut, and several investigations aimed at scientific validation of its traditional uses and a humble scientific investigation aimed at isolation and identification of active constituents of crude extracts.[...] Read More.

Keywords: Juglans regia, nutritional value, bioactivity, clinical trial, traditional use, toxicity.

2021, 20(1), 1-6;

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Review

Gamma irradiation mediated agriculture

Issa. Piri, Mehdi. Babayan*, Abolfazl. Tavassoli and Mehdi. Javaheri

Abstract: Lately, radiation technology is widely used to produce changes in the product characteristics leading to the development of new products. Gamma irradiation is capable of hydrolyzing chemical bonds, thereby cleaving large molecules of starch into smaller fragments of dextrin that may be either electrically charged or uncharged as free radicals. These changes may affect the physical and rheological properties of irradiated foods, resulting in increased solubility of starch, decreased swelling power, and decreased viscosity of starch paste. Irradiation of gamma rays on bud wood can produce higher frequencies of mutation, leading to the creation of new variants compared to the control. Macronutrients (carbohydrates, proteins and lipids) content are relatively stable against irradiation doses up to 10 kGy, on the other hand, gamma irradiation affects proteins by causing conformational changes, oxidation of amino acids, rupturing of covalent bonds and formation of protein free radicals. Radiation mediated morphological, structural and functional changes in a plant are governed by the intensity and duration of the gamma irradiation.[...] Read More.

Keywords: Irradiation, Foods sterilized, Mutation, Biochemical change, Agriculture.

2021, 20(1), 1-6;

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Research Article

Identification of a potent antiviral terpenes and coumarins from Tunisian caprifig latex, Jrani variety

Houda LAZREG AREF*, Mahjoub AOUNI, Jean Pierre CHAUMON, Khaled SAID and Abdelwaheb FEKIH

Abstract: The aim of this study was to search for new antiviral agents from Tunisian Jrani caprifig latex (Ficus carica L., Moraceae). Terpenes and coumarins were identified by gas chromatography–mass spectrometry (GC-MS) analysis in hexane and hexane ethyl-acetate (1:1, v/v) extracts, and used in experiments to test their influence on a series of viruses, namely Herpes simplex (HSV-1), Adenovirus (ADV) and Echovirus type 11 (ECV-11). To evaluate the capacity of the extracts inhibition of viruses replication cycles by preventing their adsorption and their penetrations in the cells (by interaction with the cellular receivers designed for these viruses) or by inhibition of their intracellular replication or by virus inhibition after a direct contact under microscopic observation of cytopathic effect (CPE). Extracts inhibited virus multiplication in tested techniques at the concentrations of 19.5 and 39 µg/ml, respectively. All extracts had no cytotoxic effect on Vero cells at all tested concentrations. In conclusion, some compounds of Jrani latex which possess antiviral activities may be due to the high level of Triterpens. Their mode of action against the tested viruses was found to be at all stages of multiplication, suggesting the potential use of this compound for treatment of the infection caused by these viruses.[...] Read More.

Keywords: Ficus carica, caprifig, latex, HSV-1, HSV-2, ECV-11, ADV, coumarins, terpens.

2021, 20(1), 1-6;

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Research Article

Assessment of the ahyI gene affected biofilm formation, motility, extracellular virulence and the pathogenicity in a fish model of infection

Weihua Chu*, Yan Jiang, Liu Yongwang and Wei Zhu

Abstract: Aeromonas hydrophila is a pathogen that causes disease in a wide range of homeothermic and poikilothermic hosts due to its multifactorial virulence. The production of many of these virulence determinants is associated with high cell density, a phenomenon that might be regulated by quorum sensing. The quorum sensing system regulates the expression of several virulence factors in a wide variety of pathogenic bacteria. To investigate the pathogenic role of quorum sensing system in A. hydrophila, We constructed an ahyI mutant strain of a fish-clinical isolate YJ-1, named YJ-1∆AhyI. Compared with the wild-type strain, the ahyI mutant strain exhibited a significant decrease of total extracellular virulent activity, and decreased in biofilm formation, intraperitoneal LD50 of YJ-1∆AhyI were more than 109 CFU, about 104 times higher than the parent strain. These results suggest that A. hydrophila is able to regulate its extracellular virulent factors and biofilm formation by quorum sensing systems, and indicate that disruption of quorum sensing could be a good alternative strategy to combat infections caused by A. hydrophila.[...] Read More.

Keywords: Aeromonas hydrophila, quorum sensing, biofilm, virulence factors.

2021, 20(1), 1-6;

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Research Article

Assessment of the H9N2 virus spreading in various organs of the infected SPF chickens at different days after inoculation

Somayeh Asadzadeh Manjili, Iradj sohrabi Haghdoost, Pejman Mortazavi, Hamid Habibi, Hadi lashini and Esmaeil Saberfar*

Abstract: H9N2 Avian influenza virus (AVI) infection is a major cause of economic losses in poultry industry. Therefore further study to explain the virus pathogenesis is necessary. In this study tissue tropism and dissemination of A/chicken/Iran/11T/99(H9N2) virus in various organs of specific pathogen free (SPF) chickens were investigated. Fifty 2-week-old chickens hatched from SPF eggs were divided randomly into two groups. Forty chicks in the experimental and ten chicks in the control group. Experimental chicks were inoculated intranasally-intraorally with the virus. Samples of lung, trachea, pancreas, thymus, spleen, brain, bursa of fabricius, proventriclus, cloaca and kidney were aseptically collected at 1, 3, 5, 7, 9 and 10 day post inoculation (DPI). A reverse transcriptase polymerase chain Reaction (RT-PCR) test was performed for virus detection. Viral RNA was detected in the respiratory system on days 3, 5 and 7 PI. The virus was also found in the kidney on days 3,5,7,9 PI and in the pancreas on days 3 and 5 PI. Viral RNA was observed only on day 5 PI in cloaca. The virus was not detected in the blood, brain and immune system. The virus was not found from any organs on day 10 PI. These results suggest that H9N2 AIV has tropism for respiratory, digestive and urinary system following intranasal/intraoral inoculation.[...] Read More.

Keywords: Avian influenza, H9N2, SPF, RT-PCR.

2021, 20(1), 1-6;

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Research Article

A study of various biological wastewater treatment processes

AYANDA Olushola Sunday* and AKINSOJI Olatunbosun Seun

Abstract: Nitrification is an important biological process in nitrogen cycling and has a significant effect on effluent quality in wastewater treatment. Nitrification occurs in two steps by two types of chemoautotrophic bacteria, the ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB). The ammonia oxidizing bacteria is responsible for the oxidation of ammonia with oxygen into nitrite and is often the rate-limiting step in nitrification in wastewater treatment plants. Hence, a better understanding of the ecology, microbiology and chemistry of ammonia oxidizing bacteria in biological wastewater treatment systems is necessary in order to enhance treatment performance and control. A detailed review of various biological wastewater treatment processes, ammonia oxidizing bacteria and archaea; economic importance, problems, various molecular techniques for the investigation of the diversity and community structure, as well as the isolation of ammonia oxidizing bacteria were discussed.[...] Read More.

Keywords: Wastewater, activated sludge process, nitrification, ammonia oxidizing bacteria, ammonia oxidizing archaea, nitrite oxidizing bacteria, PCR primers.

2021, 20(1), 1-6;

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