BackgroundAntioxidant compounds like phenols and flavonoids scavenge free radicals and thus inhibit the oxidative mechanisms that lead to control degenerative and other diseases. The aim of this study was to investigate the antioxidant activity in vitro, total phenolic and flavonoid contents in ethanol extracts and fractions of Crescentia cujete leaves and stem bark.MethodsCrescentia cujete leaves and bark crude ethanol extract (CEE) and their partitionates petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF) and aqueous (AQF) were firstly prepared. Different established testing methods, such as 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radical, ferric reducing power (FRP), and total antioxidant capacity (TAC) assays were used to detect the antioxidant activity. Further, the total yield, total phenolic (TPC) and total flavonoid contents (TFC) of CEE and all the fractions were determined. Ethanol extracts of both leaves and stem bark were also subjected to preliminary phytochemical screening to detect the presence of secondary metabolites, using standard phytochemical methods (Thin layer chromatography and spray reagents).ResultsPhytochemical screening of crude ethanol extract of both leaves and stem bark revealed the presence of steroids, flavonoids, saponins, tannins, glycosides and terpenoids. All the fractions and CEE of leaves and bark exhibited antioxidant activities, however, EAF of leaves showing the highest antioxidant activity based on the results of DPPH, FRP and TAC assay tests. The above fraction has shown the significant DPPH scavenging activity (IC50 = 8.78 μg/ml) when compared with standard ascorbic acid (IC50 =7.68 μg/ml). The TAC and FRP activities increased with increasing crude extract/fractions content. The TPC (371.23 ± 15.77 mg GAE/g extract) and TFC (144.64 ± 5.82 mg QE/g extract) of EAF of leaves were found significantly higher as compared to other solvent fractions for both leaves and bark. TPC were highly correlated with the antioxidant activity (R2 = 0.9268 and 0.8515 in DPPH test for leaves and bark, respectively).ConclusionThe results of the study show that leaves of C. cujete possesses significant free radical scavenging properties compared with stem bark and a clear correlation exists between the antioxidant activity and phenolic content.

BackgroundThe various parts of Cresecentia cujete have some important biological activities. In folklore medicine leaves are used to treat hematomas, tumors and hypertension. Fruit decoction is used to treat diarrhea, stomachaches, cold, bronchitis, cough, asthma, and urethritis. The present study was designed to explore the anti-inflammatory and antibacterial potential of C. cujete leaves and stem bark. Anti-inflammatory activity was evaluated by in vitro human red blood cell (HRBC) membrane stabilization method and antibacterial activity by disc diffusion method.MethodsIn vitro anti-inflammatory activity was evaluated by human red blood cell (HRBC) membrane stabilization method while in vitro antibacterial activity was evaluated using cultures of Escherichia coli and Staphylococcus aureus by disc diffusion method. Total phenolic (TPC) and total flavonoid contents (TFC) of the crude extract and fractions were also determined by Folin–Ciocalteu’s phenol reagent and by aluminium chloride method, respectively.ResultsThe crude ethanol extract (CEE) of leaves and bark (concentration of each 1.0 mg/ml) demonstrated strong membrane stabilizing activity (53.86 and 61.85 % protection, respectively), whereas their chloroform fractions (CHF) revealed moderate activity (48.74 ± 0.56 and 43.55 ± 6.20 %, respectively) compared with standard aspirin (concentration 0.10 mg/ml) which showed 75.81 % protection in this test. All the samples showed a dose dependent anti-inflammatory activity in HRBC membrane stabilization test. Total phenolic (TPC) and total flavonoid contents (TFC) of the crude extract and fractions were also determined. Again, in in vitro antibacterial study, the extractives exhibited potent antibacterial activity.ConclusionResults from this study showed that the leaves and bark of C. cujete possessed anti-inflammatory as well as antibacterial activities indicating that the plant extract has therapeutic potential against the bacterial infection and also have effect on disease processes by causing destabilization of biological membranes.

Herbal medicines have traditionally been used worldwide for the prevention and treatment of liver disease with fewer adverse effects. The leaves of the Syzygium jambos (SJL) plant were chosen and studied for their antioxidant activity in vitro and hepatoprotective activity in vivo. The antioxidant activity of the ethanol extract was examined in vitro using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay, reducing capacity, total phenol, total flavonoid content, and total antioxidant capacity. The extract had significant dose-dependent antioxidant activity in all in vitro experiments. IC 50 values of SJL and ascorbic acid (standard) were found to be 14.10 and 4.87 μg/mL, respectively, according to a DPPH radical scavenging assay. Hepatoprotective activity of the plant extract was evaluated in a rat model of carbon tetrachloride (CCl 4 )-induced liver damage. CCl 4 significantly altered serum marker enzymes, total bilirubin, total protein, and liver weight. The extract caused these values to return to normal in rats with CCl 4 -induced liver damage that were given SJL. This indicated the hepatoprotective potential of SJL and was comparable to use of the standard drug silymarin. Thus, the present study revealed that SJL may have antioxidant and hepatoprotective activity.

Zebrafish pou5f1, also known as pou2, encodes a POU-family transcription factor that is transiently expressed in the prospective midbrain and anterior hindbrain during gastrulation, governing brain development. In the present study, we found that the main regulatory elements reside in the proximal upstream DNA sequence from ؊2.2 to ؊0.12 kb (the ؊2.2/؊0.1 region). The electrophoretic gel mobility shift assay (EMSA) revealed four functional octamer sequences that can associate with zebrafish Pou2/Pou5f1. The expression of mutated reporter constructs, as well as EMSA, suggested that these four octamer sequences operate in a cooperative manner to drive expression in the mid/hindbrain. We also identified a retinoic acid (RA) -responsive element in this proximal region, which was required to repress transcription in the posterior part of the embryo. These data provide a scheme wherein pou2/pou5f1 expression in zebrafish embryos is regulated by both an autoregulatory loop and repression by RA emanating from the posterior mesoderm. Developmental Dynamics 237:1373-1388, 2008.

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It is concluded that all the extracts possess potential analgesic and CNS depressants activity. This study also showed that different fractions of methanol extract could be potential sources of new antimicrobial agents.

Background: Reactive oxygen species (ROS) and free radicals are produced during normal physiologic events in a healthy organism. Under pathological conditions ROS are overproduced resulting oxidative stress. This leads to oxidative modifications of the cellular membranes or intracellular molecules. It is accepted that the intake of antioxidant substances reinforces the defense against ROS. Aims: To evaluate the antioxidant activity of various solvent fractions of leaves extract of the plant Pterygota alata. Methods: Crude ethanol extract (CEE) of P. alata leaves and its various fractions such as n-hexane (HF), chloroform (CF), ethyl acetate (EF), and aqueous (AF) were subjected to assay for antioxidants activity. The in vitro antioxidant property was investigated by employing various established systems such as 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay, ferric reducing power assay, and total antioxidant capacity by the phosphomolybdenum assay. Mice with carbon tetrachloride (CCl 4 )-induced liver injury were used to assess antioxidant effect in vivo by examining the levels of malondialdehyde and tissue protein, and the activities of most important antioxidant enzyme, superoxide dismutase using standard procedures. Results: Among the CEE and various fractions, CF exhibited strong antioxidant ability in vitro. The liver of CCl 4 -intoxicated animals exhibited a significant (p < 0.001) decrease in the superoxide dismutase level and a significant (p < 0.001) increase in the malondialdehyde level. Mice treated with CF and standard drug silymarin caused these values to return to normal level in CCl 4 -induced liver damage. Conclusion: The present study provides evidence that CF of CEE of P. alata leaves possesses excellent in vitro and in vivo antioxidant effects, which can be a potential source of natural antioxidants and should be further exploited for its use in clinical medicine.

In vertebrate embryos, positioning of the boundary between the midbrain and hindbrain (MHB) and subsequent isthmus formation are dependent upon the interaction between the Otx2 and Gbx genes. In zebrafish, sequential expression of gbx1 and gbx2 in the anterior hindbrain contributes to this process, whereas in mouse embryos, a single Gbx gene (Gbx2) is responsible for MHB development. In the present study, to investigate the regulatory mechanism of gbx2 in the MHB/isthmic region of zebrafish embryos, we cloned the gene and showed that its organization is conserved among different vertebrates. Promoter analyses revealed three enhancers that direct reporter gene expression after the end of epiboly in the anterior-most hindbrain, which is a feature of the zebrafish gbx2 gene. One of the enhancers is located upstream of gbx2 (AMH1), while the other two enhancers are located downstream of gbx2 (AMH2 and AMH3). Detailed analysis of the AMH1 enhancer showed that it directs expression in the rhombomere 1 (r1) region and the dorsal thalamus, as has been shown for gbx2, whereas no expression was induced by the AMH1 enhancer in other embryonic regions in which gbx2 is expressed. The AMH1 enhancer is composed of multiple regulatory subregions that share the same spatial specificity. The most active of the regulatory subregions is a 291-bp region that contains at least two Pax2-binding sites, both of which are necessary for the function of the main component (PB1-A region) of the AMH1 enhancer. In accordance with these results, enhancer activity in the PB1-A region, as well as gbx2 expression in r1, was missing in no isthmus mutant embryos that lacked functional pax2a. In addition, we identified an upstream conserved sequence of 227bp that suppresses the enhancer activity of AMH1. Taken together, these findings suggest that gbx2 expression during the somitogenesis stage in zebrafish is regulated by a complex mechanism involving Pax2 as well as activators and suppressors in the regions flanking the gene.