International Journal of Biology 

About: International Journal of Biology is an academic journal published by Canadian Center of Science and Education. The journal publishes majorly in the area(s): Population & Germination. It has an ISSN identifier of 1916-9671. It is also open access. Over the lifetime, 883 publications have been published receiving 5280 citations.

Current Usage of Symbiosis and Associated Terminology

Abstract: Confusion has afflicted the definition of symbiosis for over 130 years. Despite the lack of discussion in recent times, the usage of symbiosis has evolved and appears to be stabilizing to broader interpretations. Current usage of symbiosis and its associated terminology in 10 current general biology (GB) and 10 general ecology (GE) textbooks is presented. The restrictive definition (i.e. symbiosis = mutualism) has essentially disappeared. All GB textbooks (100%) surveyed used an explicit or implicit “de Bary” definition of symbiosis (i.e. mutualism, commensalism, and parasitism), while only 40% of GE textbooks did the same. General ecology textbooks also included 30% defining symbiosis to constitute all species interactions and 30% that completely avoided usage of the term. When combining GB and GE textbooks to analyze symbiotic usage, 85% defined mutualism, commensalism, and parasitism as symbiotic interactions. Also, 70% considered a symbiosis to be a species interaction that is “intimate,” with 45% of those both “intimate and constant.” Unfortunately, only 5% used the terms ecto -/ endosymbiosis , which help discern intimacy and constancy in species interactions. Usage of symbiont (55%) was preferred over symbiote (0%). Predator and prey were defined as organisms (vs. animals) in 90% of GB and GE textbooks, while 55% and 75% described carnivores and herbivores as organisms, respectively. Only 25% discussed predation, parasitism, parasitoidism, and grazing/herbivory, with only one (5%) integrating these +/- agonistic interactions in relation to intimacy and lethality. Data reveals trend of biologists/ecologists using broader definitions.

Heterosis and combining ability analysis for yield and related-yield traits in hybrid rice.

Abstract: Study of combining ability and heterosis were conducted on 12 F1 hybrids along with seven rice genotypes (three cytoplasmic male sterile lines and four restorer varieties) to know the pattern of inheritance of some morphological traits for selecting superior genotypes. The experiment was carried out according to line x tester mating design, during 2007-08. Analysis of variance revealed significant differences among genotypes, crosses, lines, testers and line x tester interactions for tiller number, plant height, days to 50% flowering, panicle length, number of spikelets per panicle, spikelet fertility and grain yield traits. Variances of SCA were higher than the GCA variances for traits except for plant height which indicated predominance of non-additive gene action in the inheritance of the traits. The highest heterosis (106.60%) was observed in cross IR68899A x Poya followed by other eight crosses for yield and most of its related traits. The proportional contribution of testers was observed to be higher than that of the interactions of line x tester that revealed the higher estimates of GCA variance that is additive gene action among the testers used. Within CMS parents, IR62829A and among male parents, IR50 and Poya were observed to be good general combiners for most of the characters studied. The cross combinations IR62829A x Mosa-tarom, IR68899A x Poya, IR58025A x IR50 and IR58025A x Poya were observed to be good specific cross combinations for grain yield and most of its related traits due to highly significant SCA and heterotic effects.

Antibacterial activity of some folklore medicinal plants used by Bakhtiari tribal in Southwest Iran

Abstract: In this study, antibacterial activity of ethanol extract and essential oil of 10 Iranian folklore herbs including, Heracleum lasiopetalum Boiss., Satureja bachtiarica Bunge., Thymus daenensis Celak., Ziziphora teniur L., Echiophora platyloba L., Dracocephalum multicaule Benth., Kelussia odoratissima Mozff., Mentha longifolia Hudson., Achillea kellalensis Boiss. and Stachys lavandulifolia Vahl. were investigated against of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae by agar disc diffusion and serial dilution assays. Most of the extracts and essential oils showed relatively high antibacterial activity against all the tested bacteria with the diameter of inhibition zone ranging between 8 and 23 mm. Of the plants studied, the most active extracts were those obtained from essential oil of Satureja bachtiarica and Thymus daenensis. The MIC values for active extract and essential oil ranging between 0.039 and 10 mg/ml. The results obtained appeared to confirm the antibacterial potential of the plants investigated. In conclusion it can be said that the extracts and essential oils of Satureja bachtiarica and Thymus daenensis could be used as natural antibacterial agents in the food preservation and human health.

Pseudomonas aeruginosa - Pathogenesis and Pathogenic Mechanisms

Abstract: Pseudomonas aeruginosa is a common bacterium, Gram-negative opportunistic pathogen capable of infecting humans with compromised natural defenses and causing severe pulmonary disease. It is one of the leading pathogen associated with nosocomial infections. It has a vast arsenal of pathogenicity factors that are used to interfere with host defenses. Pathogenesis in P. aeruginosa facilitates adhesion, modulate or disrupt host cell pathways, and target the extracellular matrix. The propensity of P. aeruginosa to form biofilms further protects it from antibiotics and the host immune system. P. aeruginosa is intrinsically resistant to a large number of antibiotics and can be acquired resistance to many others, making treatment difficult. P. aeruginosa provokes a potent inflammatory response during the infectious process. The majority of mortalities in immunocompromised patients; cystic fibrosis, can be attributed to the progressive decline of lung function resulting from chronic infection by pathogens such as P. aeruginosa. Antibiotic treatment of chronic P. aeruginosa infections may temporarily suppress symptoms; however, they do not eradicate the pathogen. Lung diseases caused by P. aeruginosa are a leading cause of death in immunocompromised individuals as well as in children. Although immunocytes recruitment is critical to augment the host defense, excessive neutrophil accumulation results in life-threatening diseases, such as acute lung injury, as well as acute respiratory distress syndrome. Several virulence factors have been studied for their roles as potential vaccine candidate, although there is currently no clinically accepted vaccine. Understanding host-pathogen interaction is critical for the development of effective therapeutic strategies to control the damage in the lung.

Antimicrobial activities of Aframomum melegueta (alligator pepper).

Abstract: Antibacterial activity of Aframomum melegueta was tested on salmonella spp, Escherichia coli, Shigella spp and klebsiella spp. Ethanol and distilled water were used as solvents for the extraction of the plant. The ethanolic extract was found to be most effective at high concentration of 50mg/ml on all the isolates. The zones of inhibition of klebsiella spp, salmonella spp, E. coli and Shigella spp are 30mm,15mm,20mm,and 15mm respectively with ethanolic extract. The aqueous extract was found to be less effective when compared with ethanolic extract. The phytochemcial analysis carried out on Aframomum melegueta revealed the presence of alkaloids, tannins, saponin, steroids, cardiacglycoside, flavonoid, terpenoids and phenol. The presence of these phytochemcials support the use of this plant as antimicrobial agent. Aframomum melegueta can therefore be used as antimicrobial agent against the groups of Enterobacteriaceae tested.