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The current method to detect antibody titre against infectious bursal disease virus (IBDV) in chickens is based on enzyme-linked immunosorbent assay (ELISA) using whole virus as coating antigen. Coating the ELISA plates requires a purified or at least semi-purified preparation of virus as antigen, which needs special skills and techniques. In this study, instead of using whole virus, recombinant protein of hexahistidine tag (His 6 tag) and VPX protein of IBDV expressed in E. coli was used as an alternative antigen to coat the ELISA plates. There was a good correlation coefficient (R 2 = 0.972) between the results of the ELISA using plates coated with monoclonal antibody against His 6 tag and those of the commercial IBDV ELISA kit. Hence, His 6 tag and VPX recombinant protein expressed in E. coli has the potential for the development of ELISA for the measurement of IBDV-specific antibody.

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Acta Alimentaria
Authors:
S. Omar
,
R. Abd Ghani
,
H. Khaeim
,
A.H. Sghaier
, and
M. Jolánkai

Abstract

Nitrogen (N) is one of the most essential nutrients affecting the yield and quality of maize (Zea mays L.). A field experiment was conducted at the experimental plot of the Department of Agronomy, The Hungarian University of Agriculture and Life Sciences, Hungary, to investigate the effect of nitrogen fertilisation on the yield and quality of maize. The experimental site included four observation plots with a net of 2 × 5 m size. Four N levels of T1, T2, T3, and T4 were sprayed at indicated plants in four replications according to treatment viz. 0, 50, 100, and 150 kg N ha−1. Nitrogen application in general does not significantly affect maize yield, its components, or grain quality. However, out of the four N treatments, the optimal N application between 50–100 kg N ha−1 potentially increased the yield, also the total expression of protein and starch contents in maize can be achieved with the right amount of N fertiliser, indicating that the treatment could produce a high grain yield as well as high protein and starch contents. Good N fertilising practice will boost the maize's nutritional value and make it more significant in the agriculture in the future. In addition, more research and assessment are essential to acquire the most benefit from the effect of optimal N application on maize yield and quality, and the findings could be beneficial to researchers and growers.

Open access

Abstract

Soybean is one of the most important leguminous crops that contributes to human alimentation and animal feed. Soybean grain with its high protein and valuable lipid content is an essential component for the food and feed industries worldwide. Apart from the genetically determined quality characteristics of a certain variety, management practices may have an influence on the manifestation of quality parameters. At the Department of Agronomy, Hungarian University of Agriculture and Life Sciences, agronomic impacts on grain yield, protein and lipid content of soybean crop has been studied in a replicated field trial. Nitrogen (N) application and various means of weed control were studied, and grain yields were evaluated in accordance with the treatments. The results obtained suggest, that N topdressing has positive but no significant effect on grain yield, however, the means of weed control resulted in an almost twofold yield improvement compared to the control. The treatments had diverse effects regarding both protein and lipid contents of the crop yield, however, significant protein and lipid yield improvement of the crop could be observed.

Open access
Journal of Flow Chemistry
Authors:
Druval S. De Sá
,
Bojan A. Marinkovic
,
Eric C. Romani
,
Tommaso Del Rosso
,
Rodrigo O. M. A. de Souza
,
Alessandro Massi
, and
Omar Pandoli

We present prototyping of meso- and microfluidic photocatalytic devices, functionalized through incorporation of TiO2 nanoparticles in polydimethylsiloxane (PDMS), and comparison of their efficiencies for the degradation of rhodamine B (10−5 mol/L). The prototyping of the photocatalytic devices involves simple and low-cost procedures, which includes microchannels fabrication on PDMS, deposition and impregnation of TiO2 on PDMS, and, finally, plugging on the individual parts. For the microfluidic device with 13 μL internal volume, photocatalytic TiO2–PDMS composite was sealed by another PDMS component activated by O2 plasma (PDMS–TiO2–PDMS). For the mesofluidic device, a homemade polyetheretherketone (PEEK) flow cell with 800 μL internal volume was screwed on a steel support with a glass slide and the photocatalytic composite. The photocatalytic activities of the devices were evaluated using two different pumping flow systems: a peristaltic pump and a syringe pump, both at 0.05 mL/min under the action of 365 nm ultraviolet (UV) light. The characterization of TiO2–PDMS composite was performed by confocal Raman microscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The photocatalytic microreactor was the most efficient, showing high organic dye photodegradation (88.4% at 12.5 mW/cm2).

Restricted access
Acta Chromatographica
Authors:
Omar M. Khalaf
,
Mosad A. Ghareeb
,
Amal M. Saad
,
Hassan M. F. Madkour
,
Ahmed K. El-Ziaty
, and
Mohamed S. Abdel-Aziz

Different solvent extracts of the aerial parts of Senna italica (Mill.) were investigated for their chemical constituents and biological activities. Moreover, bio-guided fractionation led to isolation and identification of six compounds, namely: physcion (1), emodin (2), 2-methoxy-emodin-6-O-β-d-glucopyranoside (3), 1-hydroxy-2-acetyl-3-methyl-6-hydroxy-8-methoxynaphthalene (tinnevellin) (4), quercetin 3-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (rutin) (5), and 1,6,8-trihydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene (6). The chemical structures of these compounds were established via 1D and 2D 1H- and 13C-NMR spectroscopy. Ethyl acetate and n-butanol extracts as well as compound 3 were evaluated for their anticancer activity against tumor cell lines. The tested extracts showed a moderate to weak activity, while compound 3 showed a moderate activity against human liver cancer (Hep G2) and breast cancer (MCF-7) cell lines with IC50 values of 57.5 and 42.3 μg/mL, respectively. Both ethyl acetate and n-butanol extracts exhibited antimicrobial activities with different strengths, i.e., ethyl acetate exhibited antimicrobial activity against seven test microbes while n-butanol extract showed antimicrobial activity against all tested microbes. This is the first report for the isolation of compound 3 as a new compound from S. italica growing in Egypt.

Open access