Vol 7, No 2 (2022)

Table of Contents

Research Articles

872 Views, 111 PDF Downloads
Abrar Akbar, Rita Rahmeh, Mohamad Kishk, Batool Akbar, Mustafa AL-Shamali, Dalal Al-Baijan
DOI:10.26789/AEB.2022.02.005

Abstract

Soil contamination by polycyclic aromatic hydrocarbons (PAHs) and heavy metals is a major concern affecting soil quality. Bioremediation is an efficient approach to decontaminate these pollutants while posing the lowest risk to the environment. This technique is based on  identifying microorganisms with the metabolic potential to degrade the pollutants. In this study, the physiochemical properties of oil-contaminated soils in Kuwait were investigated. The soil had alkaline pH (8.36) with a salinity of 0.08% and PAHs compounds were detected at high concentrations (pyrene, 1212 mg/kg), (phenanthrene, 710 mg/kg) and (fluorene 326 mg/kg). Heavy metals such as iron, aluminum, sodium, magnesium, vanadium, copper, etc., were also detected in the soil samples. Then, selective screening for PAH degraders was performed and assessed by colony forming units (CFU) and 16S rDNA gene sequences to determine their growth profiles and taxonomical identification. In total, 21 strains were selected for their resistance to PAHs, which include Pseudomonas (9), Burkholderia (6), Bacillus (2), Bordetella (1), Microbacterium (1), Micrococcus (1), and Kocuria (1). Among all, the growth by Burkholderia sp. P14, in the presence of phenanthrene and fluorene, has maintained a stationary phase from day 5 to 8 with a 6 log CFU/ml bacterial count. The draft genome of the Burkholderia contaminans P14 strain comprised 68 contigs with 8,584,157bp, 66% GC content, 4 rRNA and 75 tRNA. A total of 80 genes were involved in the degradation of the benzoate, naphthalene, and PAH . Genes that encode the PAH degradation were clustered into four distinct groups, including pcaHG, pcaB, pcaIJ, and pcaKFR and were found to be in contigs 5, 11, 8 and 13 of B. contaminans P14, respectively. KEGG analysis suggested that PAHs were degraded in P14 via the protocatechuate and catechol branches of the β-ketoadipate protocatechuate degradation pathway. The genomic island regions in P14 differed from those in the reference genome of B. contaminans M14, indicating the novelty and genomic recombination of the strain. Genomic information on P14 has helped clarify the molecular mechanisms involved in PAH catabolism. Burkholderia contaminans P14 strain will enhance the bioremediation of oil-contaminated soils.

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217 Views, 55 PDF Downloads
Dominic Zhongxian Gu
DOI:10.26789/AEB.2022.02.004

Abstract

Observation has been made and is registered for the event of the naturally fell cotton tree (Bombax ceiba L.) flowers on the ground in terms of their orientation and distribution to the cardinal directions. By collecting data from the natural fall of the tree flowers on the ground, the data were then grouped to four arbitrary groups according to the cardinal directions. The results show a clear tendency of the flowers to be more aligned to the East or West directions, a non-random event of distribution. To compare and verify the collected data, a simulation experiment was also conducted using the commercially available badminton shuttlecocks to simulate the fall, and the distribution and orientation. The data of badminton shuttlecocks, though not perfectly random, are much closer to a random event through the repeated simulations. The overall results indicate that the distribution and orientation of the cotton tree flowers on ground are not a random event, and this may have fundamental biological and physical reasons deserving further investigations.

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21-25
300 Views, 109 PDF Downloads
Ankita Chatterjee, Nida Afreen
DOI:10.26789/AEB.2022.02.003

Abstract

The presence of hormones, drugs and chemicals in the environment are disrupting the ecosystem. The existence of chemicals in the environment is a threat to the ecosystem as they have dangerous effects on animals, plants and microbes. Progesterones are steroid hormones used for human contraceptives and therapeutic purposes as well as promoting animal growth. The cases of consumption of progesterone for medical purposes are much higher than estrogens, however, much studies related to estrogens have been conducted thereby neglecting the effects of progesterone. This invention focuses on removal of progesterone using fungal strain. Aspergillus niger NAAC efficiently degraded the progesterone content and transformed it into non-toxic end product. The uniqueness of this study involves preparation of a formulated product which would store the fungal strain and maintain its viability. The bioformulation was prepared using used vegetable cooking oil mixed with water as carrier. The bioformulation would reduce the efforts required to isolate the microorganism for regular usage and can be commercialized for large scale applications. To determine the storage conditions of bioformulation, various parameters were analysed which showed that storing the formulation in air tight container at room temperature would result in maximum longevity of the efficient strain.

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15-20
860 Views, 91 PDF Downloads
Nguyen Khoi Nghia, Nguyen Thi Kieu Oanh, Nguyen Hoai Thanh, Le Thi Xa, Duong Minh Vien, Chau Thi Anh Thy
DOI:10.26789/AEB.2022.02.002

Abstract

The aim of this study was to isolate and select salt tolerant bacteria having both functions in phosphorus solubilization and phosphatase synthesis from rice-shrimp farming soil in saline areas in Mekong River Delta of Vietnam. Phosphorus solubilizing bacteria were isolated on National Botanical Research Institute's Phosphate (NBRIP) agar medium containing 1% NaCl and the activity of phosphatase enzyme was determined by disodium p-nitrophenyl phosphate reagent method at a wavelength of 420 nm. The result showed that from 15 saline soil samples, a total of 95 strains of phosphorus solubilizing bacteria were isolated and 19 of them showed their good phosphorus solubilization. The results about phosphatase activities of these 19 strains illustrated that TBT5-3 bacterial strain was the highest phosphatase producing strain with an amount of 0.377 U/mL after 10 days of incubation. This strain showed its best phosphatase producing capacity when cultured in the liquid culture medium containing pH 5, 1% NaCl, glucose and urea under the shaking speed of 120 rpm. Based on 16S rRNA gene sequence analysis this phosphatase synthesizing bacterial strain was genetically identified as species of Bacillus sp. TBT5-3 since 100% of this train sequence is affiliated with Bacillus megaterium.

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5-14

Opinion

452 Views, 118 PDF Downloads
Ji-Dong Gu
DOI:10.26789/AEB.2022.02.001

Abstract

Technology has been playing a very important role in the advancement of science, and big breakthroughs in science are dependent upon technologies available from time to time. Between science and technology, a good understanding is required so that available technologies can be used most efficiently and effectively to solving the targeted questions in scientific research. Genome nucleotide sequencing as an available technology after several generations of the technical improvement is capable of extract the full nucleotide sequences of any single organism or a mixed population of organisms in a given sample. This technology has a major important role in medicine and health science for diagnosis of the microorganisms and early detection of genetic diseases. In microbial ecology and applied microbiology, it is now fashionable to sequence the microbial community, the microbiome, so that the community composition and diversity are described from air, soil, water, sludge to skin and gut of animals, including humans. This routine practice, too frequently used by far too many, neither provide any significant insights of knowledge nor unravel the fundamental science in any way, but it serves as a cosmetic decoration for publication mostly. Because of this, not sequencing or sequencing less is the view expressed here to alert researchers for a better focus on the research questions, and the selection and implementation of the necessary physical science methods to obtain the solid research data that can advance science in a significant way. Publication driven experiments to produce more papers are eroding the essence of science, especially the pure spirit of science.

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