Search results for: threatened species
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3309

Search results for: threatened species

1479 Preparation of CuAlO2 Thin Films on Si or Sapphire Substrate by Sol-Gel Method Using Metal Acetate or Nitrate

Authors: Takashi Ehara, Takayoshi Nakanishi, Kohei Sasaki, Marina Abe, Hiroshi Abe, Kiyoaki Abe, Ryo Iizaka, Takuya Sato

Abstract:

CuAlO2 thin films are prepared on Si or sapphire substrate by sol-gel method using two kinds of sols. One is combination of Cu acetate and Al acetate basic, and the other is Cu nitrate and Al nitrate. In the case of acetate sol, XRD peaks of CuAlO2 observed at annealing temperature of 800-950 ºC on both Si and sapphire substrates. In contrast, in the case of the films prepared using nitrate on Si substrate, XRD peaks of CuAlO2 have been observed only at the annealing temperature of 800-850 ºC. At annealing temperature of 850ºC, peaks of other species have been observed beside the CuAlO2 peaks, then, the CuAlO2 peaks disappeared at annealing temperature of 900 °C with increasing in intensity of the other peaks. Intensity of the other peaks decreased at annealing temperature of 950 ºC with appearance of broad SiO2 peak. In the present, we ascribe these peaks as metal silicide.

Keywords: CuAlO2, silicide, thin Films, transparent conducting oxide

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1478 The White Stork (Ciconia ciconia) in the Wetlands of North East of Algeria

Authors: Aicha Beya Mammeria, Idir Bitam

Abstract:

Our study focuses on the distribution of the white stork "Ciconia ciconia L. 1758" in the wetlands of El Tarf (North eastern of Algeria): recognized by its remarkable number of breeding pairs, monitoring of nesting, using a GPS has been performed in an attempt to explain the functioning of populations and population strategies for an overall design of its distribution, which has not so far been investigated in this region. Between 2012 and 2013, the number of breeding pairs has increased considerably from 174 in 1996 to 475 in 2007 and 968 in 2013. It should be noted that in the distribution of breeding pairs between 1996 and 2011, there is a significant development since the density of nests increased from 25.22 in 1996 to 84.16 couples/100 km² in 2013. More endemic bread apears in the region, this fluctuation is related to climatic change and changing season. Changes related to local climatic conditions might induce binding conditions for the development of this species.

Keywords: white stork, Ciconia ciconia, wetland El Tarf, northeast Algeria, climatic changing, density

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1477 Optimization of Process Parameters for Peroxidase Production by Ensifer Species

Authors: Ayodeji O. Falade, Leonard V. Mabinya, Uchechukwu U. Nwodo, Anthony I. Okoh

Abstract:

Given the high utility of peroxidase in several industrial processes, the search for novel microorganisms with enhanced peroxidase production capacity is of keen interest. This study investigated the process conditions for optimum peroxidase production by Ensifer sp, new ligninolytic proteobacteria with peroxidase production potential. Also, some agricultural residues were valorized for peroxidase production under solid state fermentation. Peroxidase production was optimum at an initial medium pH 7, incubation temperature of 30 °C and agitation speed of 100 rpm using alkali lignin fermentation medium supplemented with guaiacol as the most effective inducer and ammonium sulphate as the best inorganic nitrogen. Optimum peroxidase production by Ensifer sp. was attained at 48 h with specific productivity of 12.76 ± 1.09 U mg⁻¹. Interestingly, probable laccase production was observed with optimum specific productivity of 12.76 ± 0.45 U mg⁻¹ at 72 h. The highest peroxidase yield was observed with sawdust as solid substrate under solid state fermentation. In conclusion, Ensifer sp. possesses the capacity for enhanced peroxidase production that can be exploited for various biotechnological applications.

Keywords: catalase-peroxidase, enzyme production, peroxidase, polymerase chain reaction, proteobacteria

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1476 Identification and Characterization of Small Peptides Encoded by Small Open Reading Frames using Mass Spectrometry and Bioinformatics

Authors: Su Mon Saw, Joe Rothnagel

Abstract:

Short open reading frames (sORFs) located in 5’UTR of mRNAs are known as uORFs. Characterization of uORF-encoded peptides (uPEPs) i.e., a subset of short open reading frame encoded peptides (sPEPs) and their translation regulation lead to understanding of causes of genetic disease, proteome complexity and development of treatments. Existence of uORFs within cellular proteome could be detected by LC-MS/MS. The ability of uORF to be translated into uPEP and achievement of uPEP identification will allow uPEP’s characterization, structures, functions, subcellular localization, evolutionary maintenance (conservation in human and other species) and abundance in cells. It is hypothesized that a subset of sORFs are translatable and that their encoded sPEPs are functional and are endogenously expressed contributing to the eukaryotic cellular proteome complexity. This project aimed to investigate whether sORFs encode functional peptides. Liquid chromatography-mass spectrometry (LC-MS) and bioinformatics were thus employed. Due to probable low abundance of sPEPs and small in sizes, the need for efficient peptide enrichment strategies for enriching small proteins and depleting the sub-proteome of large and abundant proteins is crucial for identifying sPEPs. Low molecular weight proteins were extracted using SDS-PAGE from Human Embryonic Kidney (HEK293) cells and Strong Cation Exchange Chromatography (SCX) from secreted HEK293 cells. Extracted proteins were digested by trypsin to peptides, which were detected by LC-MS/MS. The MS/MS data obtained was searched against Swiss-Prot using MASCOT version 2.4 to filter out known proteins, and all unmatched spectra were re-searched against human RefSeq database. ProteinPilot v5.0.1 was used to identify sPEPs by searching against human RefSeq, Vanderperre and Human Alternative Open Reading Frame (HaltORF) databases. Potential sPEPs were analyzed by bioinformatics. Since SDS PAGE electrophoresis could not separate proteins <20kDa, this could not identify sPEPs. All MASCOT-identified peptide fragments were parts of main open reading frame (mORF) by ORF Finder search and blastp search. No sPEP was detected and existence of sPEPs could not be identified in this study. 13 translated sORFs in HEK293 cells by mass spectrometry in previous studies were characterized by bioinformatics. Identified sPEPs from previous studies were <100 amino acids and <15 kDa. Bioinformatics results showed that sORFs are translated to sPEPs and contribute to proteome complexity. uPEP translated from uORF of SLC35A4 was strongly conserved in human and mouse while uPEP translated from uORF of MKKS was strongly conserved in human and Rhesus monkey. Cross-species conserved uORFs in association with protein translation strongly suggest evolutionary maintenance of coding sequence and indicate probable functional expression of peptides encoded within these uORFs. Translation of sORFs was confirmed by mass spectrometry and sPEPs were characterized with bioinformatics.

Keywords: bioinformatics, HEK293 cells, liquid chromatography-mass spectrometry, ProteinPilot, Strong Cation Exchange Chromatography, SDS-PAGE, sPEPs

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1475 Evaluation of Antibiotic Resistance and Extended-Spectrum β-Lactamases Production Rates of Gram Negative Rods in a University Research and Practice Hospital, 2012-2015

Authors: Recep Kesli, Cengiz Demir, Onur Turkyilmaz, Hayriye Tokay

Abstract:

Objective: Gram-negative rods are a large group of bacteria, and include many families, genera, and species. Most clinical isolates belong to the family Enterobacteriaceae. Resistance due to the production of extended-spectrum β-lactamases (ESBLs) is a difficulty in the handling of Enterobacteriaceae infections, but other mechanisms of resistance are also emerging, leading to multidrug resistance and threatening to create panresistant species. We aimed in this study to evaluate resistance rates of Gram-negative rods bacteria isolated from clinical specimens in Microbiology Laboratory, Afyon Kocatepe University, ANS Research and Practice Hospital, between October 2012 and September 2015. Methods: The Gram-negative rods strains were identified by conventional methods and VITEK 2 automated identification system (bio-Mérieux, Marcy l’etoile, France). Antibiotic resistance tests were performed by both the Kirby-Bauer disk-diffusion and automated Antimicrobial Susceptibility Testing (AST, bio-Mérieux, Marcy l’etoile, France) methods. Disk diffusion results were evaluated according to the standards of Clinical and Laboratory Standards Institute (CLSI). Results: Of the totally isolated 1.701 Enterobacteriaceae strains 1434 (84,3%) were Klebsiella pneumoniae, 171 (10%) were Enterobacter spp., 96 (5.6%) were Proteus spp., and 639 Nonfermenting gram negatives, 477 (74.6%) were identified as Pseudomonas aeruginosa, 135 (21.1%) were Acinetobacter baumannii and 27 (4.3%) were Stenotrophomonas maltophilia. The ESBL positivity rate of the totally studied Enterobacteriaceae group were 30.4%. Antibiotic resistance rates for Klebsiella pneumoniae were as follows: amikacin 30.4%, gentamicin 40.1%, ampicillin-sulbactam 64.5%, cefepime 56.7%, cefoxitin 35.3%, ceftazidime 66.8%, ciprofloxacin 65.2%, ertapenem 22.8%, imipenem 20.5%, meropenem 20.5 %, and trimethoprim-sulfamethoxazole 50.1%, and for 114 Enterobacter spp were detected as; amikacin 26.3%, gentamicin 31.5%, cefepime 26.3%, ceftazidime 61.4%, ciprofloxacin 8.7%, ertapenem 8.7%, imipenem 12.2%, meropenem 12.2%, and trimethoprim-sulfamethoxazole 19.2 %. Resistance rates for Proteus spp. were: 24,3% meropenem, 26.2% imipenem, 20.2% amikacin 10.5% cefepim, 33.3% ciprofloxacin and levofloxacine, 31.6% ceftazidime, 20% ceftriaxone, 15.2% gentamicin, 26.6% amoxicillin-clavulanate, and 26.2% trimethoprim-sulfamethoxale. Resistance rates of P. aeruginosa was found as follows: Amikacin 32%, gentamicin 42 %, imipenem 43%, merpenem 43%, ciprofloxacin 50%, levofloxacin 52%, cefepim 38%, ceftazidim 63%, piperacillin/tacobactam 85%, for Acinetobacter baumannii; Amikacin 53.3%, gentamicin 56.6 %, imipenem 83%, merpenem 86%, ciprofloxacin 100%, ceftazidim 100%, piperacillin/tacobactam 85 %, colisitn 0 %, and for S. malthophilia; levofloxacin 66.6 % and trimethoprim/sulfamethoxozole 0 %. Conclusions: This study showed that resistance in Gram-negative rods was a serious clinical problem in our hospital and suggested the need to perform typification of the isolated bacteria with susceptibility testing regularly in the routine laboratory procedures. This application guided to empirical antibiotic treatment choices truly, as a consequence of the reality that each hospital shows different resistance profiles.

Keywords: antibiotic resistance, gram negative rods, ESBL, VITEK 2

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1474 Flavonoids and Phenolic Acids from the Aerial Parts of Alyssum alyssoides

Authors: Olga St. Tsiftsoglou, Diamanto M. Lazari, Eugene L. Kokkalou

Abstract:

Most of Alyssum species of Brassicaceae family have been mainly studied for their contribution in ecology. In this study, A. alyssoides was examined for its chemical substitutes. The methanol extract of its aerial parts was fractionated with liquid-liquid extraction (distribution) with four different solvents of increasing polarity: diethyl ether, ethyl acetate, 1-butanol and water. The diethyl ether and ethyl acetate extracts were further studied for their chemical composition. So far, secondary metabolites which belong to phenolics were isolated by using several chromatographic methods (C.C. and HPLC) and were identified by using spectroscopic methods (UV/Vis, NMR and MS): two phenolic acids (p-hydroxy-benzoic acid and 3-methoxy-4-hydroxy-benzoic acid (vanillic acid)), and five flavonoids, which are derivatives of flavonol: kaempferol 3-O-β-D-glucopyranoside (astragalin), kaempferol 3-O-(6′′-α-L-rhamnopyranosyl)-β-D-glucopyranoside (nicotiflorin), quercetin 3-O-β-D-glucopyranoside (isoquercetin), isorhamnetin-3-O-β-D-glucopyranoside, and isoramnetin 3-O-(6′′-α-L-rhamnopyranosyl)-β-D-glucopyranoside (narcissin).

Keywords: Alyssum, chemical substitutes, flavonoids, phenolic acids

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1473 DFT Study of Half Sandwich of Vanadium (IV) Cyclopentadienyl Complexes

Authors: Salem El-Tohami Ashoor

Abstract:

A novel new vanadium (IV) complexes incorporating the chelating diamido cyclopentadienyl {ArN(CH2)3NAr)}2-((ηn-Cp)Cp)} (Ar = 2,6-Pri2C6H3)(Cp = C5H5 and n = 1,2,3,4 and 5) have been studied with calculation of the properties of species involved in various of cyclopentadienyl reaction. These were carried out under investigation of density functional theory (DFT) calculation, and comparing together. Other methods, explicitly including electron correlation, are necessary for more accurate calculations; MB3LYP (Becke) (Lee–Yang–Parr) level of theory often being used to obtain more exact results. These complexes were estimated of electronic energy for molecular system, because it accounts for all electron correlation interactions. The optimised of [V(ArN(CH2)3NAr)2Cl(η5-Cp)] (Ar = 2,6-Pri2C6H3 and Cp= C5H5) was found to be thermally more stable than others of vanadium cyclopentadienyl. In the meantime the complex [V(ArN(CH2)3NAr)2Cl(η1-Cp)] (Ar = 2,6-Pri2C6H3 and Cp= C5H5) which is showed a low thermal stability in case of the just one carbon of cyclopentadienyl can be insertion with vanadium metal centre. By using Dewar-Chatt-Duncanson model, as a basis of the molecular orbital (MO) analysis and showed the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital LUMO.

Keywords: vanadium (IV) cyclopentadienyl complexes, DFT, MO, HOMO, LUMO

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1472 Development of Folding Based Aptasensor for Ochratoxin a Using Different Pulse Voltammetry

Authors: Rupesh K. Mishra, Gaëlle Catanante, Akhtar Hayat, Jean-Louis Marty

Abstract:

Ochratoxins (OTA) are secondary metabolites present in a wide variety of food stuff. They are dangerous by-products mainly produced by several species of storage fungi including the Aspergillus and Penicillium genera. OTA is known to have nephrotoxic, immunotoxic, teratogenic and carcinogenic effects. Thus, needs a special attention for a highly sensitive and selective detection system that can quantify these organic toxins in various matrices such as cocoa beans. This work presents a folding based aptasensors by employing an aptamer conjugated redox probe (methylene blue) specifically designed for OTA. The aptamers were covalently attached to the screen printed carbon electrodes using diazonium grafting. Upon sensing the OTA, it binds with the immobilized aptamer on the electrode surface, which induces the conformational changes of the aptamer, consequently increased in the signal. This conformational change of the aptamer before and after biosensing of target OTA could produce the distinguishable electrochemical signal. The obtained limit of detection was 0.01 ng/ml for OTA samples with recovery of up to 88% in contaminated cocoa samples.

Keywords: ochratoxin A, cocoa, DNA aptamer, labelled probe

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1471 The Côa Valley Ecosystem (Douro, Portugal) as a Cultural Landscape. Approach to the Management Challenges

Authors: Mariana Durana Pinto, Thierry Aubry, Eduarda Vieira

Abstract:

The Côa River is one of the tributaries of the Douro River, which in turn connects two Portuguese regions: Beira-Alta (Serra das Mesas, Sabugal) and Trás-os-Montes (Douro River, Vila Nova de Foz Côa). The river, which is approximately 140 kilometres in length, is surrounded by characteristic Northern-Estearn Portugal landscape. The dominant flora in the region includes olive and almond trees and vines, which provide habitat for a diverse range of native species. These include mammals such as the lynx and Iberian wolf, as well as birds of prey such as the Egyptian vulture and the griffon vulture. Additionally, herbivorous species such as red deer and roe deer also inhabit the region. However, the Vale Côa is inextricably linked with the rocky outcrops bearing the emblematic open-air Upper Palaeolithic rock art, indeed, it houses the world's largest collection of prehistoric open-air rock art, inscribed on the World Heritage list by UNESCO in 1998. From the initial discovery of the first engravings in 1991 to the present day, approximally 1,500 panels with rock art, mostly engravings and carving, but also some paintings, have been discovered, inventoried and recorded spanning from earlu Upper Paleolithic to the 20th century. The study and interpretation of the engravings and its geoarchaeological context, allow the construction of a chronological timeline of the human occupation and graphical production in this region. The area has been inhabited since the Early Palaeolithic, with human communities exploiting the diversity of the natural resources of the environment and adapting it to their needs. This led to the creation of an archaeological and historical cultural landscape.The region is currently inhabited by rural communities whose primary source of income is derived from agricultural activities, with a particular focus on olive oil and wine production, including the emblematic Vinho do Porto. Additionally, the region is distinguished by activities such as stone exploration and extraction (e.g. schist and granite quarries) and tourism. The latter has progressively assumed a role in the promotion and development of the region, primarily due to the engravings of the Côa Valley itself, as well as the Alto Douro Wine Region. Furthermore, this cultural landscape has been inscribed in the UNESCO World Heritage Site in 2001. The aforementioned factors give rise to a series of challenges and issues pertaining to the management and safeguarding of rock art on a daily basis. These include: I) the management of conflicts between cultural heritage and economic activity (between Rock art and vineyards, both classified as World Heritage Sites); II) the management of land-use planning in areas where the engravings are located (since the areas with engravings are larger than those identified as buffer zones by UNESCO); III) the absence of the legal figure of an 'archaeological park' and the need to solve this issue; IV) the management of tourist pressure and unauthorised visits; and V) the management of vandalism (as a consequence of misinformation and denial).

Keywords: Douro and Côa Valleys, archaeological cultural landscapes, rock art, Douro wine, conservation challenges

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1470 Mechanical Simulation with Electrical and Dimensional Tests for AISHa Containment Chamber

Authors: F. Noto, G. Costa, L. Celona, F. Chines, G. Ciavola, G. Cuttone, S. Gammino, O. Leonardi, S. Marletta, G. Torrisi

Abstract:

At Istituto Nazionale di Fisica Nucleare – Laboratorio Nazionale del Sud (INFN-LNS), a broad experience in the design, construction and commissioning of ECR and microwave ion sources is available. The AISHa ion source has been designed by taking into account the typical requirements of hospital-based facilities, where the minimization of the mean time between failures (MTBF) is a key point together with the maintenance operations, which should be fast and easy. It is intended to be a multipurpose device, operating at 18 GHz, in order to achieve higher plasma densities. It should provide enough versatility for future needs of the hadron therapy, including the ability to run at larger microwave power to produce different species and highly charged ion beams. The source is potentially interesting for any hadron therapy facility using heavy ions. In this paper, we analyzed the dimensional test and electrical test about an innovative solution for the containment chamber that allows us to solve our isolation and structural problems.

Keywords: FEM analysis, electron cyclotron resonance ion source, dielectrical measurement, hadron therapy

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1469 Post Harvest Preservation of Mango Fruit Using Freeze Drying and Tray Drying Methods

Authors: O. A. Adeyeye, E. R. Sadiku, Selvam Sellamuthu Periyar, Babu Perumal Anand, B. Nambiar Reshma

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Mango is a tropical fruit which is often labelled as ‘super-fruit’ because of its unquantifiable benefits to human beings. However, despite its great importance, mango is a seasonal fruit, and only very few off-seasonal species are available in the market for consumption. Therefore, in order to overcome the seasonal variation and to increase the shelf-life of mango fruits, different drying methods are considered In this study, freeze drying and tray drying methods were used to preserve two different cultivars of mango from South Africa. Moisture content, total soluble solid, ascorbic acid, total phenol content (TPC), antioxidant activity (DPPH) and organoleptic tests were carried out on the samples before and after drying. The effects of different edible preservatives and selected packaging materials used were analyzed on each sample. The result showed that freeze drying method is the best method of preserving the selected cultivar.

Keywords: postharvest, mangos, cultivar, total soluble solid, total phenol content, antioxidant

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1468 Mechanical Transmission of Parasites by Cockroaches’ Collected from Urban Environment of Lahore, Pakistan

Authors: Hafsa Memona, Farkhanda Manzoor

Abstract:

Cockroaches are termed as medically important pests because of their wide distribution in human habitation including houses, hospitals, food industries and kitchens. They may harbor multiple drug resistant pathogenic bacteria and protozoan parasites on their external surfaces, disseminate on human food and cause serious diseases and allergies to human. Hence, they are regarded as mechanical vector in human habitation due to their nocturnal activity and nutritional behavior. Viable eggs and dormant cysts of parasites can hitch a ride on cockroaches. Ova and cysts of parasitic organism may settle into the crevices and cracks between thorax and head. There are so many fissures and clefts and crannies on a cockroach which provide site for these organisms. This study aimed with identifying role of cockroaches in mechanically transmitting and disseminating gastrointestinal parasites in two environmental settings; hospitals and houses in urban area of Lahore. Totally, 250 adult cockroaches were collected from houses and hospitals by sticky traps and food baited traps and screened for parasitic load. All cockroaches were captured during their feeding time in natural habitat. Direct wet smear, 1% lugols iodine and modified acid-fast bacilli staining were used to identify the parasites from the body surfaces of cockroaches. Among human habitation two common species of cockroaches were collected i.e. P. americana and B. germanica. The results showed that 112 (46.8%) cockroaches harbored at least one human intestinal parasite on their body surfaces. The cockroaches from hospital environment harboured more parasites than houses. 47 (33.57%) cockroaches from houses and 65 (59.09%) from hospitals were infected with parasitic organisms. Of these, 76 (67.85%) were parasitic protozoans and 36(32.15%) were pathogenic and non-pathogenic intestinal parasites. P. americana harboured more parasites as compared to B. germanica in both environment. Most common human intestinal parasites found on cockroaches include ova of Ascaris lumbricoides (giant roundworm), Trichuris trichura (whipworm), Anchylostoma deodunalae (hookworm), Enterobius vermicularis (pinworm), Taenia spp. and Strongyloides stercoralis (threadworm). The cysts of protozoans’ parasites including Balantidium coli, Entomoeba hystolitica, C. parvum, Isospora belli, Giardia duodenalis and C. cayetenensis were isolated and identified from cockroaches. Both experimental sites were significantly different in carriage of parasitic load on cockroaches. Difference in the hygienic condition of the environments, including human excrement disposal, variable habitat interacted, indoor and outdoor species, may account for the observed variation in the parasitic carriage rate of cockroaches among different experimental site. Thus a finding of this study is that Cockroaches are uniformly distributed in human habitation and act as a mechanical vector of pathogenic parasites that cause common illness such as diarrhea and bowel disorders. This fact contributes to epidemiological chain therefore control of cockroaches will significantly lessen the prevalence of illness in human. Effective control strategies will reduce the public health burden of the gastro-intestinal parasites in the developing countries.

Keywords: cockroaches, health risks, hospitals, houses, parasites, protozoans, transmission

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1467 Chemical Composition and Antimicrobial Activity of the Essential Oil of Mentha piperita Endemic in Khorasan-Iran

Authors: V. Hakimzadeh, M. Noori, M. maleki

Abstract:

The aim of this study was to determine the composition and antimicrobial effect of Mentha piperita essential oil in "in-vitro" condition. The chemical composition of the essential oil obtained by hydro-distillation was examined by GC/MS and the antimicrobial effect was studied on the growth of seven microbial species including Bacillus cereus, Pseudomonas aeruginosa and Proteus vulgaris using micro-dilution method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. Chemical composition analysis identified a total of 28 compounds in which the main components were menthol (32%), mentone (13.4), menthyl acetate (12%), 1,8-cineole (8.2%) and neomenthol (4%) representing 69.6 % of the total oil. Other separated components accounted for less than 30.4% of the oil. Results of antimicrobial analysis showed that the MIC values for Bacillus cereus, Pseudomonas aeruginosa and Proteus vulgaris was respectively 50, 200 and 100 µg/ml and the MBC was determined at 200, 400 and 200 µg/ml respectively. The results of the present study indicated that Mentha piperita essential oil had significant antimicrobial activity.

Keywords: antimicrobial activity, essential oil composition, Mentha piperita

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1466 India’s Foreign Policy toward its South Asian Neighbors: Retrospect and Prospect

Authors: Debasish Nandy

Abstract:

India’s foreign policy towards all of her neighbor countries is determinate on the basis of multi-dimensional factors. India’s relations with its South Asian neighbor can be classified into three categories. In the first category, there are four countries -Sri Lanka, Bangladesh, Nepal, and Afghanistan- whose bilateral relationships have encompassed cooperation, irritants, problems and crisis at different points in time. With Pakistan, the relationship has been perpetually adversarial. The third category includes Bhutan and Maldives whose relations are marked by friendship and cooperation, free of any bilateral problems. It is needless to say that Jawaharlal Nehru emphasized on friendly relations with the neighboring countries. The subsequent Prime Ministers of India especially I.K. Gujral had advocated in making of peaceful and friendly relations with the subcontinental countries. He had given a unique idea to foster bilateral relations with the neighbors. His idea is known as ‘Gujral Doctrine’. A dramatical change has been witnessed in Indian foreign policy since 1991.In the post-Cold War period, India’s national security has been vehemently threatened by terrorism, which originated from Pakistan-Afghanistan and partly Bangladesh. India has required a cooperative security, which can be made by mutual understanding among the South Asian countries. Additionally, the countries of South Asia need to evolve the concept of ‘Cooperative Security’ to explain the underlying logic of regional cooperation. According to C. Rajamohan, ‘cooperative security could be understood, as policies of governments, which see themselves as former adversaries or potential adversaries to shift from or avoid confrontationist policies.’ A cooperative security essentially reflects a policy of dealing peacefully with conflicts, not merely by abstention from violence or threats but by active engagement in negotiation, a search for practical solutions and with a commitment to preventive measures. Cooperative assumes the existence of a condition in which the two sides possess the military capabilities to harm each other. Establishing cooperative security runs into a complex process building confidence. South Asian nations often engaged with hostility to each other. Extra-regional powers have been influencing their powers in this region since a long time. South Asian nations are busy to purchase military equipment. In spite of weakened economic systems, these states are spending a huge amount of money for their security. India is the big power in this region in every aspect. The big states- small states syndrome is a negative factor in this respect. However, India will have to an initiative to extended ‘track II diplomacy’ or soft diplomacy for its security as well as the security of this region.Confidence building measures could help rejuvenate not only SAARC but also build trust and mutual confidence between India and its neighbors in South Asia. In this paper, I will focus on different aspects of India’s policy towards it, South-Asian neighbors. It will also be searched that how India is dealing with these countries by using a mixed type of diplomacy – both idealistic and realistic points of view. Security and cooperation are two major determinants of India’s foreign policy towards its South Asian neighbors.

Keywords: bilateral, diplomacy, infiltration, terrorism

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1465 Infection of Phlebotomus Sergenti with Leishmania Tropica in a Classical Focus of Leishmania Major in Tunisia

Authors: Kaouther Jaouadi, Jihene Bettaieb, Amira Bennour, Ghassen Kharroubi, Sadok Salem, Afif Ben Salah

Abstract:

In Tunisia, chronic cutaneous leishmaniasis due to Leishmania (L) tropica is an important health problem. Its spreading has not been fully elucidated. Information on sandfly vectors, as well as their associated Leishmania species, is of paramount importance since vector dispersion is one of the major factors responsible for pathogen dissemination. In total, 650 sandflies were captured between June and August 2015 using sticky paper traps in the governorate of Sidi Bouzid, a classical focus of L. major in the Central-West of Tunisia. Polymerase chain reaction-restriction fragment length polymorphism analysis of the internal transcribed spacer 1 and sequencing were used for Leishmania detection and identification. Ninety-seven unfed females were tested for the presence of Leishmania parasite DNA. Six Phlebotomus sergenti were found positive for L. tropica. This finding enhances the understanding of the cycle extension of L. tropica outside its original focus of Tataouine in the South-East of the country.

Keywords: cutaneous leishmaniasis, Leishmania tropica, sandflies, Tunisia

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1464 Biodegradation Effects onto Source Identification of Diesel Fuel Contaminated Soils

Authors: Colin S. Chen, Chien-Jung Tien, Hsin-Jan Huang

Abstract:

For weathering studies, the change of chemical constituents by biodegradation effect in diesel-contaminated soils are important factors to be considered, especially when there is a prolonged period of weathering processes. The objective was to evaluate biodegradation effects onto hydrocarbon fingerprinting and distribution patterns of diesel fuels, fuel source screening and differentiation, source-specific marker compounds, and diagnostic ratios of diesel fuel constituents by laboratory and field studies. Biodegradation processes of diesel contaminated soils were evaluated by experiments lasting for 15 and 12 months, respectively. The degradation of diesel fuel in top soils was affected by organic carbon content and biomass of microorganisms in soils. Higher depletion of total petroleum hydrocarbon (TPH), n-alkanes, and polynuclear aromatic hydrocarbons (PAHs) and their alkyl homologues was observed in soils containing higher organic carbon content and biomass. Decreased ratio of selected isoprenoids (i.e., pristane (Pr) and phytane (Ph)) including n-C17/pristane and n-C18/phytane was observed. The ratio of pristane/phytane was remained consistent for a longer period of time. At the end of the experimental period, a decrease of pristane/phytane was observed. Biomarker compounds of bicyclic sesquiterpanes (BS) were less susceptible to the effects of biodegradation. The ratios of characteristic factors such as C15 sesquiterpane/ 8β(H)-drimane (BS3/BS5), C15 sesquiterpane/ 8β(H)-drimane (BS4/BS5), 8β(H)-drimane/8β(H)-homodrimane (BS5/BS10), and C15 sesquiterpane/8β(H)-homodrimane (BS3/BS10) could be adopted for source identification of diesel fuels in top soil. However, for biodegradation processes lasted for six months but shorter than nine months, only BS3/BS5 and BS3/BS10 could be distinguished in two diesel fuels. In subsoil experiments (contaminated soil located 50 cm below), the ratios of characteristic factors including BS3/BS5, BS4/BS5, and BS5/BS10 were valid for source identification of two diesel fuels for nine month biodegradation. At the early stage of contamination, biomass of soil decreased significantly. However, 6 and 7 dominant species were found in soils in top soil experiments, respectively. With less oxygen and nutrients in subsoil, less biomass of microorganisms was observed in subsoils. Only 2 and 4 diesel-degrading species of microorganisms were identified in two soils, respectively. Parameters of double ratio such as fluorene/C1-fluorene: C2-phenanthrene/C3-phenanthrene (C0F/C1F:C2P/C3P) in both top and subsoil, C2-naphthalene/C2-phenanthrene: C1-phenanthrene/C3-phenanthrene (C2N/C2P:C1P/C3P), and C1-phenanthrene/C1-fluorene: C3-naphthalene/C3-phenanthrene (C1P/C1F:C3N/C3P) in subsoil could serve as forensic indicators in diesel contaminated sites. BS3/BS10:BS4/BS5 could be used in 6 to 9 months of biodegradation processes. Results of principal component analysis (PCA) indicated that source identification of diesel fuels in top soil could only be perofrmed for weathering process less than 6 months. For subsoil, identification can be conducted for weathering process less than 9 months. Ratio of isoprenoids (pristane and phytane) and PAHs might be affected by biodegradation in spilled sites. The ratios of bicyclic sesquiterpanes could serve as forensic indicators in diesel-contaminated soils. Finally, source identification was attemped for samples collected from different fuel contaminated sites by using the unique pattern of sesquiterpanes. It was anticipated that the information generated from this study would be adopted by decision makers to evaluate the liability of cleanup in diesel contaminated sites.

Keywords: biodegradation, diagnostic ratio, diesel fuel, environmental forensics

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1463 Molecular Cloning and Identification of a Double WAP Domain–Containing Protein 3 Gene from Chinese Mitten Crab Eriocheir sinensis

Authors: Fengmei Li, Li Xu, Guoliang Xia

Abstract:

Whey acidic proteins (WAP) domain-containing proteins in crustacean are involved in innate immune response against microbial invasion. In the present study, a novel double WAP domain (DWD)-containing protein gene 3 was identified from Chinese mitten crab Eriocheir sinensis (designated EsDWD3) by expressed sequence tag (EST) analysis and PCR techniques. The full-length cDNA of EsDWD3 was of 1223 bp, consisting of a 5′-terminal untranslated region (UTR) of 74 bp, a 3′ UTR of 727 bp with a polyadenylation signal sequence AATAAA and a polyA tail, and an open reading frame (ORF) of 423 bp. The ORF encoded a polypeptide of 140 amino acids with a signal peptide of 22 amino acids. The deduced protein sequence EsDWD3 showed 96.4 % amino acid similar to other reported EsDWD1 from E. sinensis, and phylogenetic tree analysis revealed that EsDWD3 had closer relationships with the reported two double WAP domain-containing proteins of E. sinensis species.

Keywords: Chinese mitten crab, Eriocheir sinensis, cloning, double WAP domain-containing protein

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1462 Metabolic Regulation of Rhizobacteria for Cool-Season Grass Tolerance to Heat Stress

Authors: Kashif Jaeel, Bingru Huang

Abstract:

Stress-induced accumulation of ethylene exacerbates drought damages in plants, and suppressing stress induction of ethylene may promote plant tolerance to heat stress. The objective of this study was to investigate the effects of endophytic bacteria (Paraburkholderia aspalathi) with 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase enzymes in suppressing ethylene production on plant tolerance to heat stress and underlying physiological mechanisms of P. aspalathi-regulation in creeping bentgrass (Agrostis stolonifera). A novel strain of P. aspalathi, ‘WSF23’, with ACC deaminase activity was used to inoculate the roots of plants (cv. ‘Penncross’) subjected to heat stress in controlled-environment chambers. Inoculation with WSF23 bacteria resulted in improved shoot and root growth during heat stress. The differential changes in metabolite regulation due to the bacterial inoculation could contribute to ACC deamination bacteria-improved heat tolerance in cool-season grass species.

Keywords: rhizobacteria, grass, heat, plant metabolism, soil bacteria

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1461 Microstructure Characterization on Silicon Carbide Formation from Natural Wood

Authors: Noor Leha Abdul Rahman, Koay Mei Hyie, Anizah Kalam, Husna Elias, Teng Wang Dung

Abstract:

Dark Red Meranti and Kapur, kinds of important type of wood in Malaysia were used as a precursor to fabricate porous silicon carbide. A carbon template is produced by pyrolysis at 850°C in an oxygen free atmosphere. The carbon template then further subjected to infiltration with silicon by silicon melt infiltration method. The infiltration process was carried out in tube furnace in argon flow at 1500°C, at two different holding time; 2 hours and 3 hours. Thermo gravimetric analysis was done to investigate the decomposition behavior of two species of plants. The resulting silicon carbide was characterized by XRD which was found the formation of silicon carbide and also excess silicon. The microstructure was characterized by scanning electron microscope (SEM) and the density was determined by the Archimedes method. An increase in holding time during infiltration will increased the density as well as formation of silicon carbide. Dark Red Meranti precursor is likely suitable for production of silicon carbide compared to Kapur.

Keywords: density, SEM, silicon carbide, XRD

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1460 Bacteria Flora in the Gut and Respiratory Organs of Clarias gariepinus in Fresh and Brackish Water Habitats of Ondo State, South/West Nigeria

Authors: Nelson R. Osungbemiro, Rafiu O. Sanni, Rotimi F. Olaniyan, Abayomi O. Olajuyigbe

Abstract:

Bacteria flora of Clarias gariepinus collected from two natural habitats namely Owena River (freshwater) and Igbokoda lagoon (brackish water) were examined using standard microbiological procedures. Thirteen bacterial species were identified. The result indicated that from the identified bacteria isolated, Vibrio sp, Proteus sp. Shigella sp. and E. coli were present in both habitats (fresh and brackish waters). Others were habitat-selective such as Salmonella sp., Pseudomonas sp, Enterococcus sp, Staphylococcus sp. that were found only in freshwater habitat. While Branhamella sp, Streptococcus sp. and Micrococcus sp. were found in brackish water habitat. Bacteria load from Owena river (freshwater) was found to be the highest load recorded at 6.21 x 104cfu. T-test analysis also revealed that there was a marked significant difference between bacterial load in guts of sampled Clarias from fresh water and brackish water habitats.

Keywords: bacteria flora, gut, Clarias gariepinus, Owena river

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1459 Paucity of Trauma Literature from a Highly Burdened Developing Country

Authors: Rizwan Sultan, Hasnain Zafar

Abstract:

Trauma is the leading cause of death among young population not only in USA but Pakistan as well. The high prevalence of disease should result in larger amount of data and larger number of publications resulting in exploring room for improvement in the field. We aimed to review trauma literature generated from Pakistan in journals indexed with PubMed from January 2010 to December 2014. Search using term “Trauma AND Pakistan” filtering for relevant dates and species human was done on Pubmed. The abstracts and articles were reviewed by the authors to collect data on a preformed performa. 114 articles were published from Pakistan during these 5 years. 64% articles were published in international journals. 63% articles were published in journals with impact factor less than 1. 54% articles were published from one of the four provinces of Pakistan. 64% of articles provided level 4 while 14% articles provided level 5 evidence on the topic. 55% articles discussed epidemiology in non-representative populations. Trauma literature from Pakistan is not only lacking significantly but is also of poor quality and is unable to offer conclusions on this particular subject. There is a lot of space for improvement in the upcoming years.

Keywords: trauma, literature, Pakistan, level of evidence

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1458 Incidence of Listeria monocytogenes in Ready-To-Eat Food Sold in Johannesburg, South Africa

Authors: Hattie Hope Makumbe, Bhekisisa Dlamini, Frederick Tabit

Abstract:

Listeria monocytogenes is one of the most important foodborne pathogens associated with ready-to-eat (RTE) food. This study investigated the incidence of Listeria monocytogenes in 80 RTE food sold in the formal (dairy and processed meat) and informal markets (vegetable salads, beef stew, and rice) of Johannesburg, South Africa. High Enterobacteriaceae, S. aureus, and E. coli counts were obtained, which ranged from 1.9-7.5 log CFU/g. Listeria monocytogenes microbial counts in the food samples ranged from 3.5-6.0 log colony forming unit per gram except in cooked rice. The Listeria monocytogenes isolates were identified using biochemical tests and confirmed with the Biolog identification system and PCR analyses. The percentage incidence for Listeria monocytogenes in ready to eat food was 12.5%. When Minimum Inhibitory Concentrations were under consideration, all disinfectants were effective against Listeria monocytogenes strains. For antimicrobial work, rates of resistance amongst the antibiotics ranged from 17-100%. Therefore, more effective preventive control strategies for Listeria monocytogenes are needed to reduce the prevalence of the pathogen in RTE food that is sold in Johannesburg.

Keywords: Listeria monocytogenes, Listeria species, ready to eat food, sanitiser efficacy

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1457 Morphological and Molecular Identification of Endophytic Colletotrichum Species from Medicinal Plants and Their Antimicrobial Potential

Authors: Gauravi Agarkar, Mahendra Rai

Abstract:

Endophytic fungi from medicinal plants are important source of numerous pharmacologically important compounds. In the present investigation, the endophytic fungi were isolated from three medicinal plants; Andrographis paniculata, Rauwolfia serpentina and Tridax procumbens. Endophytic Colletotrichum sp. were identified on the basis of cultural and morphological characteristics as well as internal transcribed spacer (ITS) sequence analysis. Antibacterial and antifungal activity of the ethyl acetate and methanol extract of endophytic Colletotrichum sp. was evaluated against seven different human pathogenic bacteria and six Candida sp. The extracts were effective and showed significant activity against all the test pathogens. In case of yeast Candida, the combined effect of extracts and standard antibiotic was enhanced greatly showing synergistic activity. Further, the extracts were assayed for Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal/Fungicidal Concentration (MBC/MFC) where, MIC values were in the range of 100-250 μg/ml. These results suggest that the endophytic Colletotrichum sp. isolated from the medicinal plants are capable of producing promising antimicrobial metabolites.

Keywords: antimicrobial, colletotrichum, endophytic fungi, medicinal plants

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1456 Effect of Intraperitoneal Administration of Ghrelin on Serum Glucose and Insulin Levels in Turkey

Authors: Habib Aghdam Shahryar

Abstract:

The aim of the present study was investigation on the effect of intraperipheral (IP) injection of ghrelin on serum insulin and glucose levels in native turkey. Seventy-two 28 day (d)-old native turkey were assigned into three treatments and four replicate for 40 days experimental rearing period: group 1, intact without any injection, group 2, injected 50 ng ghrelin/kg body weight (BW), and group 3, injected 100 ng ghrelin/kg BW. Intraperitoneal injection of rat ghrelin was conducted on d 28 and before the onset of the experimental rearing period. Blood samples were taken 12 hr after injection and 40 days after injection. The result showed glucose concentrations have been affected by administered ghrelin and significant between groups (P<0.01). Injection of ghrelin at G 100 increased glucose level of serum in 12 hr after injection and 40 days after injection (276.6 and 260.0 mg/dl, respectively). Also, by increasing the dose of injected ghrelin, insulin levels than the control group showed an increase (P < 0.001). This study suggests roles of ghrelin in serum biochemical regulation may show a different effect of ghrelin on blood parameters in avian species.

Keywords: ghrelin injection, insulin, glucose, turkey

Procedia PDF Downloads 487
1455 Antimicrobial Agents Produced by Yeasts

Authors: T. Büyüksırıt, H. Kuleaşan

Abstract:

Natural antimicrobials are used to preserve foods that can be found in plants, animals, and microorganisms. Antimicrobial substances are natural or artificial agents that produced by microorganisms or obtained semi/total chemical synthesis are used at low concentrations to inhibit the growth of other microorganisms. Food borne pathogens and spoilage microorganisms are inactivated by the use of antagonistic microorganisms and their metabolites. Yeasts can produce toxic proteins or glycoproteins (toxins) that cause inhibition of sensitive bacteria and yeast species. Antimicrobial substance producing phenotypes belonging different yeast genus were isolated from different sources. Toxins secreted by many yeast strains inhibiting the growth of other yeast strains. These strains show antimicrobial activity, inhibiting the growth of mold and bacteria. The effect of antimicrobial agents produced by yeasts can be extremely fast, and therefore may be used in various treatment procedures. Rapid inhibition of microorganisms is possibly caused by microbial cell membrane lipopolysaccharide binding and in activation (neutralization) effect. Antimicrobial agents inhibit the target cells via different mechanisms of action.

Keywords: antimicrobial agents, yeast, toxic protein, glycoprotein

Procedia PDF Downloads 369
1454 Green Walls and Living Facades: The Portuguese Experience

Authors: Andreia Cortes, Carla Pimentel-Rodrigues, Joao Almeida, Myriam Kanoun-Boule, Carla Carvalho, Antonio Tadeu, Armando Silva-Afonso

Abstract:

The adoption of green infrastructure is nowadays encouraged as an essential measure of urban planning and territorial development whenever it offers a better alternative, or is complementary, to current solutions. Green walls and living facades often provide healthy alternatives to traditional grey infrastructures, offering many benefits for both citizens and cities. Beyond the ability to improve environmental conditions and quality of life, they can augment the energy efficiency of buildings, enhance biodiversity and deliver a range of ecosystem services such as water purification, reduction of the urban heat island effect, improvement of air quality and climate change adaptation. For this communication, a systematic survey of the existing green walls and living facades in Portugal was carried out. Different systems were analyzed and compared in terms of dimensions, constructive solutions, vegetative species, maintenance necessities and environmental aspects.

Keywords: green buildings, green walls, living facades, sustainability construction

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1453 Animal Modes of Surgical or Other External Causes of Trauma Wound Infection

Authors: Ojoniyi Oluwafeyekikunmi Okiki

Abstract:

Notwithstanding advances in disturbing wound care and control, infections remain a main motive of mortality, morbidity, and financial disruption in tens of millions of wound sufferers around the sector. Animal models have become popular gear for analyzing a big selection of outside worrying wound infections and trying out new antimicrobial techniques. This evaluation covers experimental infections in animal models of surgical wounds, pores and skin abrasions, burns, lacerations, excisional wounds, and open fractures. Animal modes of external stressful wound infections stated via extraordinary investigators vary in animal species used, microorganism traces, the quantity of microorganisms carried out, the dimensions of the wounds, and, for burn infections, the period of time the heated object or liquid is in contact with the skin. As antibiotic resistance continues to grow, new antimicrobial procedures are urgently needed. Those have to be examined using popular protocols for infections in external stressful wounds in animal models.

Keywords: surgical wounds, animals, wound infections, burns, wound models, colony-forming gadgets, lacerated wounds

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1452 Biodiversity and Distribution of Tettigonioidea, Ensifera of Pakistan

Authors: Riffat Sultana Pathan, Waheed Ali Panhwar, Muhammad Saeed Wagan

Abstract:

Tettigonioidea are phytophagous insects damaging agricultural crops, forest, fruit orchards, berry shrubs, and grasses. The material was collected from different agricultural fields of rice, sugarcane, wheat, maize surrounding by different grasses. Beside this, forest, hilly areas, semi-desert and desert regions were also inspected time to time. All material was captured, killed and stored by using the standard entomological method. As a result of extensive survey fair numbers were captured from the different climatic zone of country. Seven sub-families of Tettigonioidea viz: Pseudophyllinae, Phaneropterinae, Conocephalinae, Tettigoniinae, Hexacentrinae, Mecopodinae and Decticinae came in collection. This fauna contributes 29 new records to Pakistan and 5 new species to science. Beside this, a brief description of each supra-generic category of Tettigonioidea along with photographs and synonymy is also documented. In addition to this, detailed list of host plants from Pakistan was also composed. This study provides important data for Integrated Pest Management (IPM) of Tettigonioidea biodiversity conservation and grassland restoration in Pakistan.

Keywords: agriculture, conocephalinae, pest, phaneropterinae, tettigoniidae

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1451 Cloning and Analysis of Nile Tilapia Toll-like receptors Type-3 mRNA

Authors: Abdelazeem Algammal, Reham Abouelmaatti, Xiaokun Li, Jisheng Ma, Eman Abdelnaby, Wael Elfeil

Abstract:

Toll-like receptors (TLRs) are the best understood of the innate immune receptors that detect infections in vertebrates. However, the fish TLRs also exhibit very distinct features and a large diversity, which is likely derived from their diverse evolutionary history and the distinct environments that they occupy. Little is known about the fish immune system structure. Our work was aimed to identify and clone the Nile tilapiaTLR-3 as a model of freshwater fish species; we cloned the full-length cDNA sequence of Nile tilapia (Oreochromis niloticus) TLR-3 and according to our knowledge, it is the first report illustrating tilapia TLR-3. The complete cDNA sequence of Nile tilapia TLR-3 was 2736 pair base and it encodes a polypeptide of 912 amino acids. Analysis of the deduced amino acid sequence indicated that Nile tilapia TLR-3 has typical structural features and main components of proteins belonging to the TLR family. Our results illustrate a complete and functional Nile tilapia TLR-3 and it is considered an ortholog of the other vertebrate’s receptor.

Keywords: Nile tilapia, TLR-3, cloning, gene expression

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1450 Isolation and Identification of Low-Temperature Tolerant-Yeast Strains from Apple with Biocontrol Activity

Authors: Lachin Mikjtarnejad, Mohsen Farzaneh

Abstract:

Various microbes, such as fungi and bacteria species, are naturally found in the fruit microbiota, and some of them act as a pathogen and result in fruit rot. Among non-pathogenic microbes, yeasts (single-celled microorganisms belonging to the fungi kingdom) can colonize fruit tissues and interact with them without causing any damage to them. Although yeasts are part of the plant microbiota, there is little information about their interactions with plants in comparison with bacteria and filamentous fungi. According to several existing studies, some yeasts can colonize different plant species and have the biological control ability to suppress some of the plant pathogens. It means those specific yeast-colonized plants are more resistant to some plant pathogens. The major objective of the present investigation is to isolate yeast strains from apple fruit and screen their ability to control Penicillium expansum, the causal agent of blue mold of fruits. In the present study, psychrotrophic and epiphytic yeasts were isolated from apple fruits that were stored at low temperatures (0–1°C). Totally, 42 yeast isolates were obtained and identified by molecular analysis based on genomic sequences of the D1/D2 and ITS1/ITS4 regions of their rDNA. All isolated yeasts were primarily screened by' in vitro dual culture assay against P. expansum by measuring the fungus' relative growth inhibition after 10 days of incubation. The results showed that the mycelial growth of P. expansum was reduced between 41–53% when challenged by promising yeast strains. The isolates with the strongest antagonistic activity belonged to Metschnikowia pulcherrima A13, Rhodotorula mucilaginosa A41, Leucosporidium Scottii A26, Aureobasidium pullulans A19, Pichia guilliermondii A32, Cryptococcus flavescents A25, and Pichia kluyveri A40. The results of seven superior isolates to inhibit blue mold decay on fruit showed that isolates A. pullulans A19, L. scottii A26, and Pi. guilliermondii A32 could significantly reduce the fruit rot and decay with 26 mm, 22 mm and 20 mm zone diameter, respectively, compared to the control sample with 43 mm. Our results show Pi. guilliermondii strain A13 was the most effective yeast isolates in inhibiting P. expansum on apple fruits. In addition, various biological control mechanisms of promising biological isolates against blue mold have been evaluated to date, including competition for nutrients and space, production of volatile metabolites, reduction of spore germination, production of siderophores and production of extracellular lytic enzymes such as chitinase and β-1,3-glucanase. However, the competition for nutrients and the ability to inhibit P. expansum spore growth have been introduced as the prevailing mechanisms among them. Accordingly, in our study, isolates A13, A41, A40, A25, A32, A19 and A26 inhibited the germination of P. expansum, whereas isolates A13 and A19 were the strongest inhibitors of P. expansum mycelia growth, causing 89.13% and 81.75 % reduction in the mycelial surface, respectively. All the promising isolates produced chitinase and β-1,3-glucanase after 3, 5 and 7 days of cultivation. Finally, based on our findings, we are proposing that, Pi. guilliermondiias as an effective biocontrol agent and alternative to chemical fungicides to control the blue mold of apple fruit.

Keywords: yeast, yeast enzymes, biocontrol, post harvest diseases

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