PHENOLIC COMPOSITION AND ANTIMICROBIAL ACTIVITY OF ESSENTIAL OILS FROM THE FRUIT PULP OF THE ARGAN TREE

The study of the chemical composition of essential oils, the pulp of argan leachate, the phenolic compounds and the identification of the biological activity of secondary metabolites making it possible to increase the industrial and commercial value of the argan tree in the field of cosmetics, therapeutics and nutraceuticals and to allow the protection of the argan tree and the extension of the arganieraie. After the extraction and purification of the polyphenolic compounds and the essential oils of the argan fruit pulp, we used high performance liquid chromatography coupled with mass spectrometry and UV spectroscopy (LC/UV/MS). This technique allowed us to identify 16 phenolic compounds by comparing their LC/MS mass spectrum and their retention time with literature data. The main phenolic compounds found in the fruit of the argan tree are phenolic acids, flavonoids-O-rhamnoglucosides, flavonoids-O-glycosides, flavan-3-ols and flavones. Our results also show that the pulp contains a latex which is a polyisoprene whose structure has been elucidated. Furthermore, the GC/MS analysis of the chemical composition of the essential oils of the fruit pulp of the argan tree has identified several terpenes, the majority of which are camphor, 1,8-cineode and borneol. The presence of camphor in appreciable quantity in the fruit pulp of the argan tree is very interesting because it has an insecticidal activity, these activities could be valorized on the industrial level. The essential oil of the fruit pulp of the argan tree contains phenolic compounds with antioxidant effect and terpenes with insecticidal effect can lead to its use in phytotherapy. Key words: essential oils; bio-active components; polyphenols; pulp.   Composição fenólica e atividade antimicrobiológica de óleos essenciais da polpa do fruto da árvore de Argão   RESUMO: O estudo apresenta a composição química dos óleos essenciais, da polpa do lixiviado de argão, dos compostos fenólicos e a identificação da atividade biológica de metabólitos secundários, possibilitando assim aumentar o valor industrial e comercial da árvore de argão nas áreas da cosmética, terapêutica e nutracêuticos, e além disso, permitir a proteção das árvores de argão e a extensão da arganieraie. Após a extração e purificação dos compostos polifenólicos e dos óleos essenciais da polpa do fruto de argão, utilizou-se a cromatografia líquida de alta eficiência acoplada à espectrometria de massas e espectroscopia UV (LC/UV/MS). Esta técnica permitiu identificar 16 compostos fenólicos comparando seu espectro de massa LC/MS e seu tempo de retenção com dados da literatura. Os principais compostos fenólicos encontrados no fruto da árvore de argão são ácidos fenólicos, flavonóides-O-ramnoglicosídeos, flavonóides-O-glicosídeos, flavan-3-ols e flavonas. Nossos resultados também mostram que a polpa contém um látex, que é um poliisopreno, cuja estrutura foi elucidada. Além disso, a análise GC/MS da composição química dos óleos essenciais da polpa do fruto da árvore de argão identificou vários terpenos, sendo a maioria cânfora, 1,8-cineode e borneol. A presença de cânfora em quantidade apreciável na polpa do fruto da árvore de argão é muito interessante porque tem atividade inseticida, que poderiam ser valorizadas a nível industrial. O óleo essencial da polpa do fruto da árvore de argão contém compostos fenólicos com efeito antioxidante e terpenos com efeito inseticida podendo levar ao seu uso na fitoterapia. Palavras-chave: óleos essenciais; componentes bioativos; polifenóis; polpa.The study of the chemical composition of essential oils, the pulp of argan leachate, the phenolic compounds and the identification of the biological activity of secondary metabolites making it possible to increase the industrial and commercial value of the argan tree in the field of cosmetics, therapeutics and nutraceuticals and to allow the protection of the argan tree and the extension of the arganieraie. After the extraction and purification of the polyphenolic compounds and the essential oils of the argan fruit pulp, we used high performance liquid chromatography coupled with mass spectrometry and UV spectroscopy (LC/UV/MS). This technique allowed us to identify 16 phenolic compounds by comparing their LC/MS mass spectrum and their retention time with literature data. The main phenolic compounds found in the fruit of the argan tree are phenolic acids, flavonoids-O-rhamnoglucosides, flavonoids-O-glycosides, flavan-3-ols and flavones. Our results also show that the pulp contains a latex which is a polyisoprene whose structure has been elucidated. Furthermore, the GC/MS analysis of the chemical composition of the essential oils of the fruit pulp of the argan tree has identified several terpenes, the majority of which are camphor, 1,8-cineode and borneol. The presence of camphor in appreciable quantity in the fruit pulp of the argan tree is very interesting because it has an insecticidal activity, these activities could be valorized on the industrial level. The essential oil of the fruit pulp of the argan tree contains phenolic compounds with antioxidant effect and terpenes with insecticidal effect can lead to its use in phytotherapy. Key words: essential oils; bio-active components; polyphenols; pulp.   Composição fenólica e atividade antimicrobiológica de óleos essenciais da polpa do fruto da árvore de Argão   RESUMO: O estudo apresenta a composição química dos óleos essenciais, da polpa do lixiviado de argão, dos compostos fenólicos e a identificação da atividade biológica de metabólitos secundários, possibilitando assim aumentar o valor industrial e comercial da árvore de argão nas áreas da cosmética, terapêutica e nutracêuticos, e além disso, permitir a proteção das árvores de argão e a extensão da arganieraie. Após a extração e purificação dos compostos polifenólicos e dos óleos essenciais da polpa do fruto de argão, utilizou-se a cromatografia líquida de alta eficiência acoplada à espectrometria de massas e espectroscopia UV (LC/UV/MS). Esta técnica permitiu identificar 16 compostos fenólicos comparando seu espectro de massa LC/MS e seu tempo de retenção com dados da literatura. Os principais compostos fenólicos encontrados no fruto da árvore de argão são ácidos fenólicos, flavonóides-O-ramnoglicosídeos, flavonóides-O-glicosídeos, flavan-3-ols e flavonas. Nossos resultados também mostram que a polpa contém um látex, que é um poliisopreno, cuja estrutura foi elucidada. Além disso, a análise GC/MS da composição química dos óleos essenciais da polpa do fruto da árvore de argão identificou vários terpenos, sendo a maioria cânfora, 1,8-cineode e borneol. A presença de cânfora em quantidade apreciável na polpa do fruto da árvore de argão é muito interessante porque tem atividade inseticida, que poderiam ser valorizadas a nível industrial. O óleo essencial da polpa do fruto da árvore de argão contém compostos fenólicos com efeito antioxidante e terpenos com efeito inseticida podendo levar ao seu uso na fitoterapia. Palavras-chave: óleos essenciais; componentes bioativos; polifenóis; polpa

Multispectral palmprint recognition using Pascal coefficients-based LBP and PHOG descriptors with random sampling

Local binary pattern (LBP) algorithm and its variants have been used extensively to analyse the local textural features of digital images with great success. Numerous extensions of LBP descriptors have been suggested, focusing on improving their robustness to noise and changes in image conditions. In our research, inspired by the concepts of LBP feature descriptors and a random sampling subspace, we propose an ensemble learning framework, using a variant of LBP constructed from Pascal’s coefficients of n-order and referred to as a multiscale local binary pattern. To address the inherent overfitting problem of linear discriminant analysis, PCA was applied to the training samples. Random sampling was used to generate multiple feature subsets. In addition, in this work, we propose a new feature extraction technique that combines the pyramid histogram of oriented gradients and LBP, where the features are concatenated for use in the classification. Its performance in recognition was evaluated using the Hong Kong Polytechnic University database. Extensive experiments unmistakably show the superiority of the proposed approach compared to state-of-the-art techniques

A Miniature Microstrip Antenna Array using Circular Shaped Dumbbell for ISM Band Applications

The aim of this work is the achievement, and the validation of a small microstrip patch antenna array using a circular shaped dumbbell defected ground structure. This work has been dividing into two stages: The first step is to miniaturize a microstrip patch antenna resonating at 5.8GHz, which operate in the Industrial Scientific Medical band (ISM) and the second is to use a circular defected ground structure to shift the resonance frequency of the antenna array from 5.8GHz to 2.45GHz. At last, a miniaturization up to 74.47%, relative to the original microstrip antenna array has accomplished. The antenna structure has designed, optimized and miniaturized using CST MW Studio. The obtained results have compared with Ansoft’s HFSS electromagnetic solver. The antenna array has fabricated on FR-4 substrate, and its reflection coefficient is measured

Reduction of Mutual Coupling between Closely Spaced Microstrip Antennas Arrays Using Electromagnetic Band-gap (2D-EBG) Structures

Reducing mutual coupling is a key research area in design of compact microstrip antennas arrays. To minimize the overall size of the antennas arrays, the distance between them must be very small, as a result a strong mutual coupling is appears. Periodic structures can help to design a low profile of antennas arrays and enable to improve their performances by the suppression of surface waves propagation in a given frequency range. This paper proposes a novel configuration of mushroom-like electromagnetic band-gap (2D-EBG) structure created by microstrip technology placed between two antennas arrays to reduce the mutual coupling more than -33.24dB. When 13×2 EBG structures are used, the mutual coupling reduces to -59.36dB at the operation frequency 5.8GHz of the antennas arrays. A 26.12dB mutual coupling reduction is achieved, which proves that the surface wave is suppressed. The proposed configuration is designed, optimized, and miniaturized by using electromagnetic software CST Microwave Studio. The measured results show that there is a good agreement with the computed results

Simulation numérique des transferts thermiques dans une serre agricole chauffée par un bloc solide isotherme

International audienceLes effets provoqués par le transfert thermique radiatif sur la distribution de température, l'écoulement d'air et le transfert de chaleur dans une serre contenant un bloc solide carré, isotherme et chaud, sont étudiés numériquement. Les équations différentielles gouvernant le système sont discrétisées à l'aide d'une méthode des volumes finis et le couplage pression-vitesse est traité par l'algorithme SIMPLER. Les systèmes algébriques obtenus sont résolus par la méthode des gradients conjugués. La serre est supposée de rapport de forme A=2, et les résultats sont présentés en termes d'isothermes, de lignes de courant et de nombre de Nusselt pour des nombres de Rayleigh compris entre 103 et 106

Multi-spectral palmprint recognition based on oriented multiscale log-Gabor filters

Among several palmprint recognition methods proposed recently, coding-based approaches using multi-spectral palmprint images are attractive owing to their high recognition rates. Aiming to further improve the performance of these approaches, this paper presents a novel multi-spectral palmprint recognition approach based on oriented multiscale log-Gabor filters. The proposed method aims to enhance the recognition performances by proposing novel solutions at three stages of the recognition process. Inspired by the bitwise competitive coding, the feature extraction employs a multi-resolution log-Gabor filtering where the final feature map is composed of the winning codes of the lowest filters’ bank response. The matching process employs a bitwise Hamming distance and Kullback–Leibler divergence as novel metrics to enable an efficient capture of the intra- and inter-similarities between palmprint feature maps. Finally, the decision stage is carried pout using a fusion of the scores generated from different spectral bands to reduce overlapping. In addition, a fusion of the feature maps through two proposed novel feature fusion techniques to allow us to eliminate the inherent redundancy of the features of neighboring spectral bands is also proposed. The experimental results obtained using the multi-spectral palmprint database MS-PolyU have shown that the proposed method achieves high accuracy in mono-spectral and multi-spectral recognition performances for both verification and identification modes; and also outperforms the state-of-the-art methods

A trade-off design of microstrip broadband power amplifier for UHF applications

In this paper, the design of a Broadband Power Amplifier for UHF applications is presented. The proposed BPA is based on ATF13876 Agilent active device. The biasing and matching networks both are implemented by using microstrip transmission lines. The input and output matching circuits are designed by combining two broadband matching techniques: a binomial multi-section quarter wave impedance transformer and an approximate transformation of previously designed lumped elements. The proposed BPA shows excellent performances in terms of impedance matching, power gain and unconditionally stability over the operating bandwidth ranging from 1.2 GHz to 3.3 GHz. At 2.2 GHz, the large signal simulation shows a saturated output power of 18.875 dBm with an output 1-dB compression point of 6.5 dBm of input level and a maximum PAE of 36.26%

Design of L-S band broadband power amplifier using microstip lines

This contribution introduces a novel broadband power amplifier design, operating in the frequency band ranging from 1.5 GHz to 3 GHz which cover the mainstream applications running in L and S bands. Both matching and biasing networks are synthesized by using microstrip transmission lines. In order to provide a wide bandwidth, two broadband matching techniques are deployed for this purpose, the first technique is an approximate transformation of a previously designed lumped elements matching networks into microstrip matching circuits, and the second technique is a binomial multi-sections quarter wave impedance transformer. The proposed work is based on ATF-13786 active device. The simulation results depict a maximum power gain of 16.40 dB with an excellent input and output matching across 1.5 GHz ~ 3 GHz. At 2.2 GHz, the introduced BPA achieves a saturated output power of 16.26 dBm with a PAE of 21.74%, and a 1-dB compression point of 4.5 dBm input power level. The whole circuitry is unconditionally stable over the overall bandwidth. By considering the broadband matching, the proposed design compares positively with the most recently published BPA