Open Access Original Research Article

Biodecolorization of Six Synthetic Dyes by Pleurotus ostreatus ARC280 Laccase in Presence and Absence of Hydroxybenzotriazole (HBT)

Ali M. Elshafei, Maysa A. Elsayed, Mohamed M. Hassan, Bakry M. Haroun, Abdelmageed M. Othman, Ayman A. Farrag

Annual Research & Review in Biology, Page 1-16
DOI: 10.9734/ARRB/2017/35644

Aim: The aim of the present study was to investigate the potential effect of laccase enzyme produced by the fungus Pleurotus ostreatus to decolorize six synthetic dyes in presence and absence of hydroxybenzotriazole (HBT) as a laccase mediator.

Study Design: Qualitative and quantitative evaluation for the efficiency of laccase produced by Pleurotus ostreatus to decolorize six tested dyes in the presence and absence of HBT.

Place and Duration of Study: Department of Microbial Chemistry, Genetic Engineering and Biotechnology Division, National Research Centre (NRC), Cairo, Egypt, between April 2016 and May, 2017.

Methodology: Pleurotus ostreatus ARC280 was maintained on Potato Dextrose Agar (PDA) medium and kept at 4ºC. Production of laccase was preceded by growing Pl. ostreatus on liquid media under static conditions. The efficiency of laccase obtained from P. ostreatus ARC280 on dyes decolorization was determined by the decrease in absorbance at the maximum wavelength of each dye. The efficiency of decolorization was expressed in terms of decolorization percentage.

Results: Results obtained showed that the enzyme was efficient in decolorizing Acid-Green 27 (95.33%), Acid dye Lanapel Red BM 143-PL (100%) and Congo Red (72.76%) at dye concentration of 25 mg/l; enzyme units, 0.657 U and after 6 h of incubation at 30ºC. In the presence of HBT (1 mM), the time required for reaching 100% decolorization of Acid Green-27 and Acid dye Lanapel Red BM 143-PL was reduced to the half. Absorbance reduction at the maximum wavelength was recorded with all the tested dyes indicating the efficiency of the decolorization process.

Conclusion: The results obtained indicated the effectiveness of P. ostreatus ARC280 laccase and its mediated system in the decolorization of six structurally different dyes. Addition of HBT decreased the time required to reach the maximum decolorization percentage of Acid-Green 27 and Acid dye Lanapel Red BM 143-PL to the half. The decolorization percentage of Cibacron D-Blue was greatly affected by HBT-laccase mediator system by about 45% increase.

Open Access Original Research Article

Adhesion of Heterotrophic Bacteria on the Surface of Containers Used for Well Water Storage in Garoua (North Cameroon)

Moussa Djaouda, Daniel Ebang Menye, Bouba Gaké, Moïse Nola, Thomas Njiné

Annual Research & Review in Biology, Page 1-8
DOI: 10.9734/ARRB/2017/33975

Aims: The abundance of heterotrophic bacteria adsorbed on the walls of four types (polypropylene, glass, aluminium, clay) of containers used for well water storage in Garoua was compared.

Methodology: Water samples were obtained from two wells. In each well water sample, 3 sterilized slides of each type of container were introduced, at mid-depth from the surface. Their immersion times were respectively 24, 48 and 72 h. After an immersion time, slides were aseptically removed from the water samples and transferred into sterile test tubes containing 10 ml of saline. The resulting bacterial suspension was used to determine abundance of heterotrophic bacteria adsorbed on the slides.

Results: The maximum abundance of adsorbed bacteria (8.06x104 CFU/cm2 to 2.47x106 CFU/cm2) was obtained on the clay slide while the minimum (45 CFU/cm2 to 5.90x103 CFU/cm2) was recorded on the aluminium slide from first to third day of water storage. The bacterial abundance differs significantly depending on the slide type and the duration of water storage (P <0.001).

Conclusion: Rather than using massively clay pots for drinking water storage, people in North Cameroon are recommended to use metallic or glass containers to reduce bacterial adhesion.

Open Access Original Research Article

Effects of Methyl Tert-butyl Ether (MTBE) on the Mucosal Immunity in the Small Intestine of the White Albino Mice

Luay M. M. Alkazmi, Zuhair Y. Al-Sahhaf, Hesham A. Malak, Hussein H. Abulreesh

Annual Research & Review in Biology, Page 1-11
DOI: 10.9734/ARRB/2017/35016

Some chemical compounds have a significant effect on living organisms. This is shown in the physiological and biological changes that appear on some cells and tissues of the body. The current study aimed to investigate the effect of the dissolved MTBE in drinking water on the mucosal immune cells of the small intestine of the white mice. The presence of dissolved MTBE at a concentration of 5000 ppm in drinking water has significant increase (P <0.02) of mast cells in the mucosa of mice. Similarly, at a concentration of 2500 ppm a significant increase (P <0.01) of goblet cells were observed in treated rats compared with untreated rats. The Experiment has also shown that the effect of MTBE in drinking water included the weights of animals in general, where the weight gain was weak in the treated rats compared to those where the drinking water was free of the compound. Another observation of the effects of MTBE in drinking water was the increase of the weights of some internal organs (e.g. liver, kidneys and heart) in the treated animals, as well as effects on the behavior of these animals with an obvious fatigue was observed on treated individuals. The chronic exposure of intestinal tissues to MTBE may led to inflammatory effects and /or tissue damages, and as a response the mucosal innate immunity, particularly the numbers of mast, Paneth and goblet cells were increased in synergistic fashion to play their protective role in lessen the damages caused by MTBE.

Open Access Original Research Article

Determination of Cs-137 Concentration in Some Environmental Samples around the Semipalatinsk Nuclear Test Site in the Republic of Kazakhstan

Sergazy Duyssembaev, Ainur Serikova, Eleonora Okuskhanova, Nadir Ibragimov, Nailya Bekturova, Nurgul Ikimbayeva, Yaroslav Rebezov, Olga Gorelik, Malika Baybalinova

Annual Research & Review in Biology, Page 1-8
DOI: 10.9734/ARRB/2017/35239

Cs-137 was measured in the soil, vegetation, water, milk and meat samples taken from five different settlements around the Semipalatinsk nuclear test site (SNTS) (Kazakhstan). The settlements of Sarzhal, Kainar, Akzhar, Novopokrovka and Karkaraly belong to extreme, very high, very high, high and minimal radiation risk zones, respectively. Radionuclide activities concentrations were determined using a pure Ge gamma-spectrometer (Canberra, USA) and the measured activity levels were not found to exceed the maximum allowable limits 10 Bq/kg for water and 1000 Bq/kg for meat and milk according to the guidelines of World Health Organization. The highest activity concentration levels of Cs-137 were found in soil while the lowest levels were measured in water. Vegetation, milk and meat showed intermediate levels. In soil, the highest  values were obtained on samples collected in Sarzhal (35.0±1.0 Bq/kg) and Kainar (23.0±1.0 Bq/kg).  Sarzhal also showed the most elevated levels in vegetation (2.2±0.1 Bq/kg), milk (1.8 ± 0.6 Bq/kg) and water (0.05 Bq/kg). Kainar showed the most elevated level in meat (1.8±0.6 Bq/kg). 

Open Access Original Research Article

Water Physico-chemical Characteristics, Species Diversity and Density of Zooplankton in Two Perennial Lakes of Coimbatore City (India)

R. Kalpana, P. Saravana Bhavan, R. Udayasuriyan

Annual Research & Review in Biology, Page 1-17
DOI: 10.9734/ARRB/2017/34749

In order to assess the suitability of the Ukkadam lake (Lat. 10.99° N and Long. 76.96° E) and the Singanallur lake (Lat. 10.59° N and Long. 77.88° E) of Coimbatore (Tamil Nadu, India) for inland aquaculture, the species diversity and density of zooplankton were assessed for a period of one year (December, 2015 to November, 2016) under four seasons, post-monsoon, summer, pre-monsoon and monsoon. In the Ukkadam lake, a total of 28 zooplankton species, including 7 species of Rotifera, 6 species of Cladocera, 8 species of Copepoda and 7 species of Ostracoda were identified. Their mean density were 4890 ind. l-1 for Rotifera, 5338 ind. l-1 for Cladocera, 5811 ind. l-1 for Copepoda and 8002 ind. l-1 for Ostracoda (total of 24042), and their order of dominance were Ostracoda > Copepoda > Cladocera > Rotifera. In the Singanallur lake, a total of 24 zooplankton species, of which 7 species of Rotifera, 6 species of Cladocera, 6 species of Copepoda and 5 species of Ostracoda were identified with the mean   density of 3146 ind. l-1 for Rotifera, 2492 ind. l-1 for Cladocera, 2342 ind. l-1 for Copepod and 2355 ind. l-1 for Ostracoda (total of 10337) in the following order of dominance: Rotifera > Cladocera > Ostracoda > Copepoda. This study revealed that the annual zooplankton abundance was found to be higher in the Ukkadam lake than that of the Singanallur lake (24042 ind. l-1 and 10337 ind. l-1, respectively). When looking seasonal variation both the Ukkadam and the Singanallur lakes showed maximum zooplankton abundance during summer season (25989 ind. l-1 and 10821 ind. l-1, respectively), followed by post-monsoon (24089 ind. l-1 and 9577 ind. l-1, respectively), pre-monsoon (23954 and 10807 in, respectively) and monsoon (20436 ind. l-1 and 10142 ind. l-1, respectively). In both lakes, zooplankton was positively correlated with physico-chemical parameters, such as water temperature, pH, salinity and electrical conductivity, and not properly correlated with dissolved oxygen and total dissolved solids. Regarding the diversity indices, considerable degree of differences were seen between these two lakes, the Ukkadam lake showed more diversity and density than those found in the Singanallur lake. When individual lake was considered, considerable degree of differences was seen in the species diversity of each zooplankton group in different season.