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Phenolic Contents, in vitro Antioxidant and Antimicrobial Activities of Genista microcephala Coss. & Dur.

Abstract

This study was carried out to determine the phenolic contents as well as to evaluate the antioxidant and antimicrobial activities of Genista microcephala. Total phenolic and flavonoid compounds were quantified. Antioxidant activity was evaluated by various in vitro tests, including Ferric Ion Reducing Activity (FRP), Cuprac Ion Reducing Antioxidant Capacity (CUPRAC), and total antioxidant capacities (TAC). The antimicrobial activity of ethyl acetate and butanolic extracts of G. microcephala in addition of fatty acids content of different parts of the studied plant was evaluated against human pathogenic bacteria, fish bacteria and two yeast. The used methods were agar diffusion method and the determination of minimal bactericidal and fungicidal concentrations (MBC and MFC). No significant difference was found between the two used solvents on total phenolic content (TPC). While, difference in total flavonoid content (TFC) were found to be significant. Ethylene acetate extract was the most actif regarding antioxidant assay. The tested activity seems to be due to the high content of this extract on isoflavonoids. The tested extracts demonstrated the lowest inhibition concentration for B.cereus RSKK 863.

Open access
Preparation and characterization of a porous material from an Algerian desert sand

Abstract

The objective of the present work is to prepare and characterize a porous material using quite particular and localized dunar sand (erg) of the desert near the El-Oued (south-east of Algeria). The porous material is prepared according to the mechanism of co-operative self-assembly. The method consists of polymerizing a silicic precursor (sodium silicate obtained by alkali fusion of sand with the sodium carbonate) around micelles of surfactant in an acid aqueous solution according to the sol-gel process. The elimination of the surfactant by calcining at high temperature leads to the final material which was characterized by XRF, XRD, MEB-EDX, FTIR and BET techniques.

Open access
Sex estimation using foot measurements, stature and body mass index (BMI) in a Nigerian population

Abstract

Identification of dismembered bodies recovered in disasters or crime scene is very important in forensic. This study was carried out to ascertain if foot size, body weight, height, stature and BMI can be used to predict sex using tape rule and Stadiometer scale. 150 subjects between 18 - 25yrs were recruited. Independent T-test, Pearson Correlation, Linear and Multiple Regression Analysis were determined using SPSS version 23. All measurements were higher in male than female and there was significant (p≤0.05) difference in the sex. The average foot length of 257.39mm was used to determine sex of the subjects. All foot lengths ≤ 257.39mm were presumed to belong to females while all values > 257.39mm was presumed males. Foot size and weight had the highest correlation values. Foot length gave better estimation of sex than foot breadth, BMI and weight. Results of Multiple regression equation was better than linear regression equation. In forensic anthropology, foot size has been used to predict sex. Limitation of this study is the formulae generated can only be applied to Nigerians aged 18-25 yrs. Studies should be carried out on diverse population for future inferences

Open access
The acceptors behavior in the Single and Double Doped Bi12TiO20

Abstract

The absorption coefficient of Bi12TiO20:AlI, Bi12TiO20:AlII, Bi12SiO20:P and Bi12SiO20:Al+P single crystals is measured in the spectral region of Urbach’s rule (1.52 – 2.92 eV) at room temperature. The parameters of electron-phonon interaction, Urbach’s energy and the constants of Urbach’s rule are calculated. The behavior of the acceptors Al3+ and P5+ in Urbach’s rule region has been considered.

Open access
Allenephosphonic phosphine oxides in reactions with electrophilic reagents

Abstract

The reactivity of the titled compounds towards electrophilic reagents has been investigated and new experimental evidences for the mechanism of the electrophilic addition reactions to 1,2-alkadienephosphonates have been reported

Open access
Descriptor Fingerprints and Their Application to WhiteWine Clustering and Discrimination.

Abstract

This study continues the attempt to use the statistical process for a large-scale analytical data. A group of 3898 white wines, each with 11 analytical laboratory benchmarks was analyzed by a fingerprint similarity search in order to be grouped into separate clusters. A characterization of the wine’s quality in each individual cluster was carried out according to individual laboratory parameters.

Open access
First bioacoustic and morphological data for the presence of Pelophylax bedriagae in Bulgaria

Abstract

Water frog mating calls from two localities were studied and analyzed. Recordings were made in the summer of 2010 at the Arkutino swamp near the town of Primorsko and at the Vurbitza River near the town of Momchilgrad. A total of 154 calls were analyzed and the results suggested the presence of both the Marsh frog (Pelophylax ridibundus) and the Levant frog (Pelophylax bedriagae) in both sites, with the former being more frequent in Vurbitza River, and the latter – in Arkutino. At Vurbitza, we also captured and measured 2 specimens, which morphological characteristics differed from P. ridibundus and matched those of P. bedriagae. These are the first localities for P. bedriagae in Bulgaria.

Open access
In vitro cytotoxicity of allelopathic plants Adonis vernalis L. Origanum vulgare ssp. vulgare L. and Nepeta nuda subsp. nuda

Abstract

Medicinal plants produce various secondary metabolites as a part of their chemical defence and survival in nature. These compounds have a wide range of biological activities. Nowadays, medicinal plants are used as source of allelochemicals and new effective anticancer agents. Our previous studies revealed allelopathic potential of water extracts of Adonis vernalis L. (Ranunculaceae), Origanum vulgare ssp. vulgare L. and Nepeta nuda subsp. nuda (Lamiaceae). Present study aimed to evaluate the effect of the same extracts in vitro on human hepatoma cell line SK-HEP-1. Cell proliferation/viability was assessed using Premixed WST-1 Cell Proliferation Reagent.

Adonis water extract (1.83mg/ml) had notable negative influence on cancer cell line tested. Oregano (3.5 mg/ml) also exerted negative effect, but to a lesser degree. On the contrary, nepeta water extract (6.59 mg/ml) had an opposite effect, stimulating cell proliferation. One possible explanation could be the type of extraction: after treatment with nepeta methanol extract (6.59 mg/ml) cell viability was significantly reduced.

In conclusion, Adonis vernalis and Nepeta nuda subsp. nuda possess metabolites with growth inhibitory effect on human hepatoma cell line SK-HEP-1. Further research is needed to clarify biological activity of lower concentrations which are appropriate to enable the design of new anticancer drugs.

Open access
Notes on the hatching phases and the size of the juveniles in the Snake-eyed skink Ablepharus kitaibelii (Bibron & Bory de Saint-Vincent, 1833)

Abstract

Most of the studies dealing with the Snake-eyed skink (Ablepharus kitaibelii) treat predominantly aspects of the distribution and taxonomy of the species. In the present study we provide information concerning the mechanism of hatching in the Snake-eyed skink and the dimensions of the hatched specimens. We collected data from wild animals, as well as from indoor incubated juveniles. The present study provides the first data concerning the weight of the newly hatched juveniles of the species and discuss on potential misleading data concerning the size of the juveniles in A. kitaibelii.

Open access