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Fusarium verticillioides and F. proliferatum from Syrian wheat grains: fumonisin production
No full textFusarium species are predominantly found associated with Fusarium head blight in wheat and other small-grain cereals all over the world. F. verticillioides (Fv) and F. proliferatum (Fp), the less frequently encountered species, are less pathogenic but toxigenic. The occurrence of these species in harvested wheat and cereals grains could indicate the presence of fumonisin mycotoxins. The risks of the consumption of fumonisin contaminated grains must not be ignored. In Syria, wheat is the main strategic crop and its two main products, bread and bulgur, are common food stuffs. The average consumption of bread per capita per month is 12.9 Kg.
The aim of the study was to detect the presence of fumonisins in Syrian wheat grains and the ability of Fv and Fp in their production.
Fourty-eight grain samples of durum and soft wheat were collected from different Syrian areas during years 2009 and 2010. Mycological analysis was performed on four hundred kernels for each sample. All Fusarium isolates were studied morphologically and molecularly, and then screened for their ability in producing mycotoxins in wheat cultivation. Fusarium infected samples were analyzed also for mycotoxin content using HPLC–MS/MS.
The data revealed that F. verticillioides and F. proliferatum were present in Syrian wheat grains with frequencies of 10.4% and 8.0%, respectively towards the total of Fusarium population. All the strains were able to produce fumonisins B1, B2, B3 (FB1, FB2, FB3), and 10 % of the grain samples were contaminated with low levels of FB1, FB2
Effect of fungicides and herbicides on in vitro sensitivity of Clonostachys rosea and different strains of Trichoderma
No full textEFFECT OF OSMOTIC DEHYDRATION ON KIWIFRUIT: RESULTS OF A MULTIANALYTICAL APPROACH TO STRUCTURAL STUDY
No full textThis paper presents the results of the comparison of different analytical techniques (Differential Scanning Calorimetry - DSC,
Low Field Nuclear Magnetic Resonance - LF-NMR, Light Microscopy - LM and Transmission Electron Microscopy – TEM) in order
to evaluate the mass transfer, water status and cellular compartment modifications of the kiwifruit outer pericarp tissue during osmotic dehydration treatment (OD). Two kiwifruit species, A. deliciosa and A. chinensis were submitted to OD. OD was performed in
a 61.5 % w/v sucrose solution at three different temperatures (25, 35 and 45 °C), with treatment time from 0 to 300 min. Peleg’s
model highlighted that the main response differences between the two kiwifruit species occurred during the initial phase of the osmotic treatment. DSC parameters appeared to be sensitive to water and solid exchange between fruits and osmotic solution. LF-NMR
proton T2 revealed the consequences of the water-solid exchange on the cell compartments, namely vacuole, cytoplasm plus extracellular space and cell wall. During OD, the reduction of the vacuole proton pool, detected by LF-NMR, suggested a shrinkage of such
compartment, confirmed by LM. Cell walls of outer pericarp showed considerable changes in size, structure and stain uptake during
OD observed at TEM. The proposed multianalytical approaches should enable better design of combined processing technologies
permitting the evaluation of their effects on tissue respons
Biochar addition has contrasting effects on aggregate stability dynamics of clay and sandy-loam soils
No full textBifidobacterium aerophilum sp. nov., Bifidobacterium avesanii sp. nov. and Bifidobacterium ramosum sp. nov.: Three novel taxa from the faeces of cotton-top tamarin (Saguinus oedipus L.)
No full textForty-five microorganisms were isolated on bifidobacteria selective medium from one faecal sample of an adult subject of the cotton-top tamarin (Saguinus oedipus L.). All isolates were Gram-positive, catalase-negative, anaerobic, fructose-6-phosphate phosphoketolase positive, and asporogenous rod-shaped bacteria. In this study, only eight out of the forty-five strains were characterized more deeply, whereas the others are still currently under investigation. They were grouped by BOX-PCR into three clusters: Cluster I (TRE 17T, TRE 7, TRE 26, TRE 32, TRE 33, TRE I), Cluster II (TRE CT), and Cluster III (TRE MT). Comparative analysis of 16S rRNA gene sequences confirmed the results from the cluster analysis and revealed relatively low level similarities to each other (mean value 95%) and to members of the genus Bifidobacterium. All eight isolates showed the highest level of 16S rRNA gene sequence similarities with Bifidobacterium scardovii DSM 13734T (mean value 96.6%). Multilocus sequence analysis (MLSA) of five housekeeping genes (hsp60, rpoB, clpC, dnaJ and dnaG) supported their independent phylogenetic position to each other and to related species of Bifidobacterium. The G + C contents were 63.2%, 65.9% and 63.0% for Cluster I, Cluster II and Cluster III, respectively. Peptidoglycan types were A3α l-Lys-l-Thr-l-Ala, A4β l-Orn (Lys)-d-Ser-d-Glu and A3β l-Orn-l-Ser-l-Ala in Clusters I, II and III, respectively. Based on the data provided, each cluster represented a novel taxon for which the names Bifidobacterium aerophilum sp. nov. (TRE 17T = DSM 100689 = JCM 30941; TRE 26 = DSM 100690 = JCM 30942), Bifidobacterium avesanii sp. nov. (TRE CT = DSM 100685 = JCM 30943) and Bifidobacterium ramosum sp. nov. (TRE M = DSM 100688 = JCM 30944) are proposed
Physiological responses in roots of the grapevine rootstock 140 Ruggeri subjected to Fe deficiency and Fe-heme nutrition
No full textBackground and aims In many important viticultural
areas of the Mediterranean basin, plants often face
prolonged periods of scarce iron (Fe) availability in the
soil.The objective of the present work was to perform a
comparative analysis of physiological and biochemical
responses of Vitis genotypes to severe Fe deficiency.
Methods Three grapevine rootstocks differing in susceptibility to Fe chlorosis were grown with and without
Fe in the nutrient solution.
Results Rootstock 101-14, susceptible to Fe chlorosis,
responded to severe Fe deficiency by reducing the root
activity of phosphoenolpyruvate carboxylase (PEPC)
and malate dehydrogenase(MDH),however,it accumulated
high levels of citric acid. By contrast, rootstock
110 Richter, tolerant to Fe chlorosis, maintained an
active metabolism of organic acids,but citric acid accumulation was lower than in101-14.Similarly to101-14,
rootstock SO4 showed a strong decrease in PEPC and
MDH activities. Nevertheless it maintained moderate
citric acid levels in the roots, mimicking the response
by 110 Richter.
Conclusions Root PEPC and MDH activities can be
used as tools for screening Fe chlorosis tolerance.
Conversely, organic acids accumulation in roots may
not be a reliable indicator of Fe chlorosis tolerance,
particularly under conditions of severe Fe deficiency,
because of their probable exudation by roots.Our results
show that drawing sound conclusions from screening
programs involving Fe deficiency tolerance requires
short as well as long-term assessment of responses to
Fe deprivation
Bifidobacterium. eulemuris sp. nov. isolated from the faeces of the black lemur (Eulemur macaco)
No full textForty strains of bifidobacteria were isolated from the faeces of two adult subjects of black lemur, Eulemur macaco. Twenty-five were identified as Bifidobacterium lemurum, the novel species recently described in Lemur catta. All other isolates resulted Gram-positive-staining, non-spore-forming, fructose-6-phosphate phosphoketolase positive, microaerophilic, irregular rod-shaped bacteria that often resembled Y or V shapes cells. Typing techniques revealed these isolates were nearly identical and strain LMM_E3T was chosen as representative and characterized further. Phylogenetic analysis based on 16S rRNA gene sequences clustered this isolate inside the genus Bifidobacterium and showed the highest levels of sequence similarities with Bifidobacterium lemurum DSM 28807T (99.6%), with Bifidobacterium pullorum LMG 21816T and Bifidobacterium longum subsp. infantis ATCC 15697T (96.4 % and 96.3%, respectively). Analysis of hsp60 gene sequences revealed that strain LMM_E3T was also closely related to Bifidobacterium stellenboschense DSM 23968T (93.3%). DNA-DNA reassociation value with the closest neighbour B. lemurum DSM 28807T was found to be 65.4%. The DNA base composition was 62.3 mol% G+C. Strain LMM_E3T showed a peptidoglycan structure which has not been detected in bifidobacteria so far: A3α L-Lys - L-Ser - L-Thr - L-Ala. Based on the phylogenetic, genotypic and phenotypic data, strain LMM_E3 T represents a novel species within the genus Bifidobacterium for which the name Bifidobacterium eulemuris sp. nov. is now proposed; the type strain is LMM_E3T (=DSM 100216T; = JCM 30801T)
Dose-effect studies of Coridothymus capitatus and rosmarinus officinalis essential oils on swine spermatozoa.
No full textDetection of Fumonisins in Fresh and Dehydrated Commercial Garlic
No full textAn epidemic fungal disease caused by Fusarium proliferatum, responsible for fumonisin production (FB1, FB2, and FB3), has been reported in the main garlic-producing countries in recent years. Fumonisins are a group of structurally related toxic metabolites produced by this pathogen. The aim of this work was to establish an enzyme-linked immunosorbent assay (ELISA) procedure, mostly applied to cereals, that is suitable for fumonisin detection in garlic and compare these results to those obtained by high-performance liquid chromatography (HPLC) and screening of fresh and dehydrated garlic for toxicological risk. The results show good correlation between the two analytical methods. In fresh symptomatic garlic, fumonisin levels were higher in the basal plates than those in the portions with necrotic spots. Among the 56 commercially dehydrated garlic samples screened, three were positive by ELISA test and only one was above the limit of quantitation. The same samples analyzed by HPLC showed the presence of FB1 in trace amounts that was below the limit of quantitation; FB2 and FB3 were absent. The results are reassuring, because no substantial contamination by fumonisins was found in commercial garlic
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