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Retraction: Reproducibility testing of RAPD and SSR markers in TomatoRajput S.G., Wable K.J., Sharma K.M. , Kubde P.D. and Mulay S.A

Antigenotoxicity and antioxidant activities of bitter leaf (Vernonia amygdalina Del.) accessions from different parts of Nigeria

Bitter leaf (Vernonia amygdalina Del.) plant is a tree species that is highly cultivated in Nigeria for its nutritive and therapeutic values. This study aimed to determine the antioxidant and antigenotoxicity effects (in vitro) of 52 accessions of V. amygdalina collected from six geopolitical zones of Nigeria (North East, North West, North Central, South South, East and West) by evaluating the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO-) scavenging antioxidant activities, flavonoid and phenolic contents as well as ethidium bromide-induced DNA (deoxyribonucleic acid) damage of bitter leaf. The results showed that accessions MN628016 (Oshimili South, Delta State) and MN628010 (Akoko Edo, Edo State), respectively had higher amounts of flavonoid (287.19 mg/g/FW) and phenolic (307.90 mg/g/FW) contents. The accessions MN627984 (Ikpoba Okha, Edo State) and MN627975 (Owerri, Imo State) had the highest nitric oxide (85.73%) and DPPH radical scavenging inhibitory effect (98.92%). The highest percentage fragmented DNA (45.05%), was observed in Allium cepa roots homogenised and mixed with ethidium bromide followed by the A. cepa roots homogenised and mixed with the leaf extract of V. amygdalina accession MN627977 (36.12%). However, V. amygdalina accessions MN628008 (457.62%, Warri North, Delta State) had the highest percentage increase of fragmented DNA followed by MN628024 (395.04%, Oshimili North, Delta State), MN628015 (345.54%; Aniocha North, Delta State) and MN627984 (342.04%; Ikpoba Okha, Edo State) while accession MN628010 (7.32%; Akoko Edo, Edo State) had the lowest. Accession MN628010 which possessed the highest amount of phenolic content had the lowest percentage increase of fragmented DNA and accession MN627984 which possessed the highest nitric oxide radical scavenging inhibitory effect was among the accessions with the highest percentage increase of fragmented DNA. The findings of this study suggest that the observed lowest percentage of fragmented DNA of A. cepa roots growth induced with the solution of ethidium bromide and treated with V. amygdalina accessions MN628010 extracts (antigenotoxic) could be as a result of the high antioxidant activities in the V. amygdalina accessions. In summary, the findings of this study showed that the 52 V. amygdalina accessions obtained from different locations of Nigeria will help to combat ethidium bromide induced genoxicities and any other genotoxicant that may lead to different complications in plant (A. cepa roots), as all the accessions possessed antioxidant and antigenotoxic properties, as such, possessed comparable amount of natural antioxidant activities and antigenotoxicity

Disruption of Trichoderma reesei cre2, encoding an ubiquitin C-terminal hydrolase, results in increased cellulase activity

The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1472-6750/11/103Background: The filamentous fungus Trichoderma reesei (Hypocrea jecorina) is an important source of cellulases for use in the textile and alternative fuel industries. To fully understand the regulation of cellulase production in T. reesei, the role of a gene known to be involved in carbon regulation in Aspergillus nidulans, but unstudied in T. reesei, was investigated. Results: The T. reesei orthologue of the A. nidulans creB gene, designated cre2, was identified and shown to be functional through heterologous complementation of a creB mutation in A. nidulans. A T. reesei strain was constructed using gene disruption techniques that contained a disrupted cre2 gene. This strain, JKTR2-6, exhibited phenotypes similar to the A. nidulans creB mutant strain both in carbon catabolite repressing, and in carbon catabolite derepressing conditions. Importantly, the disruption also led to elevated cellulase levels. Conclusions: These results demonstrate that cre2 is involved in cellulase expression. Since the disruption of cre2 increases the amount of cellulase activity, without severe morphological affects, targeting creB orthologues for disruption in other industrially useful filamentous fungi, such as Aspergillus oryzae, Trichoderma harzianum or Aspergillus niger may also lead to elevated hydrolytic enzyme activity in these species.Jai A Denton and Joan M Kell

Effect of preservation on the chlorophyll content, phytochemicals, and antioxidant capacity of two different varieties of pumpkin (Telfairia occidentalis) leaves

The aim of the present study was to investigate the effect of two preservation techniques (refrigeration and freezing) on the chlorophyll content, phytochemicals, and antioxidant capacity of two different varieties of pumpkin (Telfairia occidentalis) leaves over a period of two weeks. The biochemical parameters assessed include chlorophyll content, total soluble protein, reducing sugar, total phenolics, total flavonoids and ferric reducing antioxidant power (FRAP). The results of the study show that in both broad and slender leaves pumpkin varieties investigated, refrigeration and freezing for two weeks led to a significant decrease (p<0.05) in their chlorophyll contents. Total chlorophyll a and b content in the preserved broad leaf pumpkin variety (BLP) decreased by an average of 49.12%, whereas the average percentage decrease in total chlorophyll a and b observed in the preserved slender leaf variety (SLP) was 79.01% compared to their respective fresh leaves controls. Refrigeration and freezing for two weeks also resulted in a significant decrease (p<0.05) in total soluble protein and reducing sugar contents of both broad leaf (BLP) and slender leaf (SLP) varieties of pumpkin. However, the preservative methods did not significantly (p>0.05) affect the level of phenolics in the broad leaf pumpkin variety, although it was significantly decreased in the slender leaf pumpkin variety preserved by refrigeration. There was no significant difference (p>0.05) in flavonoid contents among the refrigerated, frozen and fresh leaves of the broad pumpkin leaf variety (BLP). However, the preserved slender pumpkin leaves variety (SLP) again suffered a significant decrease. Though the ferric reducing antioxidant power (FRAP) of broad leaf pumpkin variety (BLP) preserved by refrigeration (4°C) and freezing (-20°C) were slightly decreased by 20.9% and 16.1%, respectively, compared to their fresh broad leaf control, the decrease was not significant (p>0.05). On the contrary, the FRAP of the preserved slender leaf pumpkin variety (SLP) was significantly decreased (p<0.05) relative to their fresh slender leaf control. It could be inferred from the findings of this research that the broad leaf pumpkin variety (BLP) can be preserved by freezing (temperature -20°C) for a period of two weeks without any significant (p>0.05) loss of its valuable phytochemicals and antioxidant capacity compared to the slender leaf pumpkin variety.Key words: Pumpkin (Telfairia occidentalis) leaves, preservation, freezing, refrigeration, chlorophyll, phenols, flavonoids, free radicals scavenging activit

Theileria parva candidate vaccine antigens recognized by immune bovine cytotoxic T lymphocytes.

East Coast fever, caused by the tick-borne intracellular apicomplexan parasite Theileria parva, is a highly fatal lymphoproliferative disease of cattle. The pathogenic schizont-induced lymphocyte transformation is a unique cancer-like condition that is reversible with parasite removal. Schizont-infected cell-directed CD8(+) cytotoxic T lymphocytes (CTL) constitute the dominant protective bovine immune response after a single exposure to infection. However, the schizont antigens targeted by T. parva-specific CTL are undefined. Here we show the identification of five candidate vaccine antigens that are the targets of MHC class I-restricted CD8(+) CTL from immune cattle. CD8(+) T cell responses to these antigens were boosted in T. parva-immune cattle resolving a challenge infection and, when used to immunize naïve cattle, induced CTL responses that significantly correlated with survival from a lethal parasite challenge. These data provide a basis for developing a CTL-targeted anti-East Coast fever subunit vaccine. In addition, orthologs of these antigens may be vaccine targets for other apicomplexan parasites