Aims: This study is aimed at determining the molecular identification and genetic relationships of Spirogyra collected from northern Thailand using the genotyping of ISSR markers.
Study Design: The 13 Spirogyra specimens in northern Thailand will be investigated by profiling the specimens via a two-step analysis process, which includes morphological and molecular methods using ISSR markers.
Place and Duration of Study: The 13 Spirogyra specimens were collected randomly from all parts of Thailand from February 2009 to May 2011, specifically including Phrae, Nan, Chiang Rai, Chiang Mai, Tak, Mae Hong Son, Lampang, Lamphun and Phayao Provinces.
Methodology: The morphological characteristics of each sample were recorded. These characteristics included the cell dimensions (width and length) and the number and arrangement of the chloroplast spiral/granules. In addition, with regard to the molecular study, the 10 ISSR primers were amplified in order to examine the DNA fingerprints of all Spirogyra specimens.
Results: The Spirogyra specimens were classified by 5 distinct patterns as follows; Pattern 1: condensed and slightly compacted chloroplast spirals, Pattern 2: short cells with scattered chloroplast spirals, Pattern 3: long cells with fewer chloroplast spirals, Pattern 4: short cells with fewer chloroplast spirals and Pattern 5: long cells with condensed and compacted chloroplast spirals. Morphological characteristics were found to be significantly different through an examination of 5 specific traits (p< 0.05) among all of the specimens using Turkey’s criteria. The major criterion for classification involved the number and arrangement of the chloroplast spirals. Moreover, 61 fragment sizes from ISSR-PCR were analyzed using the UPGMA method. They can be separated and represented by 5 groups of the Spirogyra according to their morphology in this study. These results correspond to the morphological study, so it can be concluded that the ISSR PCR can be applied for the accurate identification of Spirogyra populations.
Conclusion: The results of both methods were used to successfully divide the Spirogyra specimens collected from northern Thailand into 5 distinct groups. The phylogenetic analysis used in this study presented useful information in the confirmation of the taxonomy of Spirogyra, which can be compared to the taxonomy that was achieved based on morphological observations that were made during molecular identification. All of which can be of significant use with regard to Spirogyra classification in Thailand.
Quinolones are an important kind of antibiotics employed in the treatment of clinical relevant bacterial infections. It is well known that quinolones causes DNA damage inducing the SOS response system of DNA repair. Many ideas about the effect of these antibiotics on bacterial physiology have been obtained through of treatment of planktonic cultures and sessile biofilms. However, despite these studies, many aspects of how quinolones affect to bacterial metabolism and growth of colonies remains still poorly understood. Here, I report that norfloxacin quinolone antibiotic interferes with the normal development of Escherichia coli K-12 old macrocolony biofilms, altering its morphology, abolishing the formation over its surface of characteristic autoaggregative chondrule-like formations observed in macracolonies non treated with norfloxacin; but intriguingly the norfloxacin treatment induces in this kind of biofilms the formation of a new kind of superficial structures that exhibit a “spider-like” morphology, which has not previously been reported. Interestingly, these spider-like formations are also found outside the colony. Most importantly, when macrocolony biofilms carrying a recA-gfp transcriptional fusion were ordered sequentially in rows, the norfloxacin promoted the SOS induction of recA-gfp activity as well as the alteration of morphology of E. coli K-12 macrocolonies in norfloxacin concentrations lower that the sub-inhibitory concentrations, in a regime of influence that is not expected to be active. The biological implications of these findings are discussed.
Due to increased environmental and toxicological problems originating from the release of toxic contaminants in the environment, it has become obvious that cheaper and reliable methods of evaluating genotoxicity of these contaminants are needed. Hence, the effect of industrial effluent from tobacco on Allium cepa L. root mitosis was investigated with the view to ascertaining its genotoxic effects using the biological test. Healthy sprouted onion roots were treated with concentrations of 20%, 50% and 100% of Tobacco wastewater for 6 h, 12 h and 18 h time duration respectively, while distilled water served as control. Healthy roots were harvested after the treatment periods and fixed in 1:3 acetic alcohol for 24h. After this, roots were hydrolysed in 1N HCl before squashing, staining with FLP-Orcein and observed on the microscope. There was significant difference in the mitotic indices between the treatment concentrations (27.71; 32.32; 27.09; 33.85) and (21.98; 26.89; 16.17; 34.04), and the control (20% 50%; 100%; control), at 6 h and 12 h respectively. However, exposures of root cells to even the least concentration beyond 12 h to 18 h produced a toxic effect on the cells and a complete inhibition of mitosis of the root cells. Similarly, the treatment concentrations induced various mitotic chromosomal aberrations such as Stickiness, C-metaphase, bridges, unequal distribution of chromosomes, breaks, laggards, vagrant and ring chromosomes at concentrations of 20%, 50% and 100%, and between 6 and 12 h exposure. These observations confirm the assumption that wastewater of tobacco has a genotoxic potential and capable of affecting DNA biosynthesis, especially when high concentrations are absorbed for a prolonged period of time.
One of the reasons Egypt do not achieve very high maize crop yield is that cultivars used commercially are bred and grown under low plant density (ca 20,000 plants/ fed; one fed= 4200 m2). Therefore, the objective of the present study was to identify maize genotypes of tolerance to high plant density in order to enhance grain productivity from unit area. Six inbred lines of maize differing in adaptive traits to high plant density were crossed in a diallel fashion. Higher plant densities (30,000 and 40,000 plants/fed) caused a significant increase in grain yield/fed (GYPF) compared with the low-density (20,000 plants/fed) by 5.7 and 6.3% for inbreds and 14.0 and 27.6% for F1 crosses, respectively. The inbreds L17, L18 and L53 proved to be tolerant (T), while the L29, L54 and L55 inbreds were sensitive (S) to high density. The T×T group of crosses exhibited better performance in most studied traits than T×S and S×S groups of crosses under the three plant densities. The cross L17 × L54 came in the 1st rank under all plant densities for both grain yield/plant and grain yield/fed; this cross gave 42.7 ard/fed (ca. 14 ton/ha) [one ard (ardab) = 140 kg] under the high plant density (40,000 plants/fed) and showed a significant superiority of 28.6% over the best check cultivar in this study (SC 2066) under this density. The crosses L17 × L18, L29 × L55, L53 × L54 and L53 × L55 came in the 2nd, 3rd, 4th and 5th ranks, for grain yield/fed under all plant densities. Grain yield/fed of all studied genotypes showed a quadratic response of increase to the increase in densities from low to high levels, except L29, L54 and L55 inbreds, which showed a quadratic response of decrease. Optimum plant density in this study differed from genotype to genotype and was the lowest (20,000 plants/fed) for the three inbreds L29, L54 and L55, but was the medium one (30,000 plants/fed) for the inbred L53 and the two crosses L17 × L29 and L54 × L55 and was the highest density (40,000 plants/fed) for the inbreds L17 and L18 and the rest of F1 crosses.
Aims: In this study, the purified cellulase was examined for its ability to deink the photocopier waste paper effluent and the application of enzymatic deinking improved ink removal.
Study Design: OFAT (One Factor At a Time).
Place and Duration of Study: Medical Labs Department of Unayza Community College, Qassim University, KSA between October 2012 and April 2013.
Methodology: Four fungal isolates were isolated from rice husks and screened for their production of cellulase and the most potent ones were selected. The resultant extracts were identified and used for deinking of photocopier waste paper. One isolate that showed efficient deinking and maximum cellulase production was identified morphologically and microscopically.
Results: The enzyme was successively optimized for its maximum productivity and purified by precipitation with 80% ammonium sulfate followed by chromatography on G-100 Sephadex. The purification procedure provided 2.36 folds purification with 64.78% yield recovery of cellulase. The maximum production was achieved in flasks with shaking speed of 200 rpm at pH 5.0, 30°C and incubation time of 5 days. SDS-PAGE indicated that the molecular weight of the purified cellulase was 71.6 KDa. Results also revealed that, the ink color was removed gradually by increasing the reaction time between cellulase and the effluent and the maximum color removal was achieved after 9 hours.
Conclusion: This study suggested that toxic pollutants like waste paper effluents (concentrated in industrial wastes and contaminated sites) can potentially be eliminated by low cost bioremediation systems using microbial cultures. The knowledge about the optimum environmental factors or conditions could help to employ biological approaches efficiently to clean up the water discharged from waste paper recycling industry. Mucor hiemalis cellulase effectively deinked wastepaper effluents.