Verrucarin A and roridin E produced on rocket by Myrothecium roridum under different temperatures and CO2 levels

2017 ◽  
Vol 10 (3) ◽  
pp. 229-236 ◽  
Author(s):  
P. Bosio ◽  
I. Siciliano ◽  
G. Gilardi ◽  
M.L. Gullino ◽  
A. Garibaldi
Keyword(s):  
Disease Severity ◽  
High Temperatures ◽  
Maximum Level ◽  
Temperature Influence ◽  
Eruca Sativa ◽  
Mycotoxin Production ◽  
Co2 Levels ◽  
The Future ◽  
Different Temperatures ◽  
Myrothecium Roridum

The behaviour of Myrothecium roridum, artificially inoculated on cultivated rocket (Eruca sativa), has been evaluated under eight different temperature and CO2 concentration combinations (from 14-18 °C to 26-30 °C and with 400-450 or 800-850 ppm of CO2). The pathogen isolate used for this study was inoculated on rocket and disease severity increased with high temperatures for both CO2 levels. Verrucarin A and roridin E mycotoxins were produced under all the tested temperatures at high CO2 conditions. The maximum level of verrucarin A was found at 14-18 °C and 800-850 ppm of CO2, and the maximum roridin E production was detected at 26-30 °C with 800-850 ppm of CO2. The results obtained in this study show that both the CO2 concentration and the temperature influence disease severity and mycotoxin production in different ways. An increase in temperature, which is favourable for attacks of the pathogen, could induce the spread of M. roridum in temperate regions, and this pathogen could take on even greater importance in the future, considering its ability to produce mycotoxins.

scholarly journals Effect of Temperature during Drying and Storage of Dried Figs on Growth, Gene Expression and Aflatoxin Production

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 134
Author(s):  
Ana Isabel Galván ◽  
Alicia Rodríguez ◽  
Alberto Martín ◽  
Manuel Joaquín Serradilla ◽  
Ana Martínez-Dorado ◽  
...  
Keyword(s):  
Gene Expression ◽  
Aflatoxin Production ◽  
Effect Of Temperature ◽  
Mycotoxin Production ◽  
Industrial Processing ◽  
Factors Associated ◽  
Different Temperatures ◽  
Major Producer ◽  
Main Factors ◽  
And Storage

Dried fig is susceptible to infection by Aspergillus flavus, the major producer of the carcinogenic mycotoxins. This fruit may be contaminated by the fungus throughout the entire chain production, especially during natural sun-drying, post-harvest, industrial processing, storage, and fruit retailing. Correct management of such critical stages is necessary to prevent mould growth and mycotoxin accumulation, with temperature being one of the main factors associated with these problems. The effect of different temperatures (5, 16, 25, 30, and 37 °C) related to dried-fig processing on growth, one of the regulatory genes of aflatoxin pathway (aflR) and mycotoxin production by A. flavus, was assessed. Firstly, growth and aflatoxin production of 11 A. flavus strains were checked before selecting two strains (M30 and M144) for in-depth studies. Findings showed that there were enormous differences in aflatoxin amounts and related-gene expression between the two selected strains. Based on the results, mild temperatures, and changes in temperature during drying and storage of dried figs should be avoided. Drying should be conducted at temperatures >30 °C and close to 37 °C, while industry processing, storage, and retailing of dried figs are advisable to perform at refrigeration temperatures (<10 °C) to avoid mycotoxin production.

Influence of Heat on Seed Germination of Cistus Laurifolius and Cistus Ladanifer

1992 ◽  
Vol 2 (1) ◽  
pp. 15 ◽  
Author(s):  
L Valbuena ◽  
R Tarrega ◽  
E Luis
Keyword(s):  
Seed Germination ◽  
High Temperatures ◽  
Exposure Time ◽  
Germination Rate ◽  
Heat Exposure ◽  
Cistus Ladanifer ◽  
Different Temperatures ◽  
Petri Dishes ◽  
Germinated Seeds

The influence of high temperatures on germination of Cistus laurifolius and Cistus ladanifer seeds was analyzed. Seeds were subjected to different temperatures for different times, afterwards they were sowed in plastic petri dishes and monitored for germinated seeds over two months.The germination rate observed in Cistus ldanifer was greater than in Cistus laurifolius. In both species, heat increased germination percentages. For Cistus laurifolius higher temperatures or longer exposure times were needed. Germination percentages of Cistus ladanifer were lower when heat exposure time was 15 minutes.It must be emphasized that germination occurred when seeds were not treated, while seeds exposed to 150�C for 5 minutes or more did not germinate.

Linear and non-linear analysis on two-dimensional steel frame under different temperatures

2019 ◽  
Vol 10 (1) ◽  
pp. 48-55
Author(s):  
Parthasarathi N. ◽  
Satyanarayanan K.S. ◽  
Prakash M. ◽  
Thamilarasu V.
Keyword(s):  
High Temperatures ◽  
Progressive Collapse ◽  
Transient State ◽  
Steel Frame ◽  
Frame Structure ◽  
Two Dimensional ◽  
Content Type ◽  
Frame Building ◽  
Different Temperatures ◽  
Steel Frame Structure

Purpose Progressive collapse because of high temperatures arising from an explosion, vehicle impact or fire is an important issue for structural failure in high-rise buildings. Design/methodology/approach The present study, using ABAQUS software for the analysis, investigated the progressive collapse of a two-dimensional, three-bay, four-storey steel frame structure from high-temperature stresses. Findings After structure reaches the temperature results like displacement, stress axial load and shear force are discussed. Research limitations/implications Different temperatures were applied to the columns at different heights of a structure framed with various materials. Progressive collapse load combinations were also applied as per general service administration guidelines. Originality/value This study covered both steady-state and transient-state conditions of a multistorey-frame building subjected to a rise in temperature in the corner columns and intermediate columns. The columns in the framed structure were subjected to high temperatures at different heights, and the resulting displacements, stresses and axial loads were obtained, analysed and discussed.

scholarly journals Effects of High Temperatures on the Physical and Mechanical Properties of Carbonated Ordinary Concrete

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Qifang Xie ◽  
Lipeng Zhang ◽  
Shenghua Yin ◽  
Baozhuang Zhang ◽  
Yaopeng Wu
Keyword(s):  
Mechanical Properties ◽  
Weight Loss ◽  
Elastic Modulus ◽  
High Temperatures ◽  
Elevated Temperatures ◽  
Physical And Mechanical Properties ◽  
Surface Characteristics ◽  
Time Service ◽  
Different Temperatures ◽  
Cooling Methods

Fires are always known for seriously deteriorating concrete in structures, especially for those with certain carbonation due to long-time service. In this paper, 75 prism specimens were prepared and divided into four groups (three carbonated groups and one uncarbonated group). Specimens were tested under different temperatures (20, 300, 400, 500, 600, and 700°C), exposure times (3, 4, and 6 hours), and cooling methods (water and natural cooling). Surface characteristics, weight loss rate, and residual mechanical properties (strength, initial elastic modulus, peak, and ultimate compressive strains) of carbonated concrete specimens after elevated temperatures were investigated and compared with that of the uncarbonated ones. Results show that the weight loss rates of the carbonated concrete specimens are slightly lower than that of the uncarbonated ones and that the cracks are increased with raising of temperatures. Surface colors of carbonated concrete are significantly changed, but they are not sensitive to cooling methods. Surface cracks can be evidently observed on carbonated specimens when temperature reaches 400°C. Residual compressive strength and initial elastic modulus of carbonated concrete after natural cooling are generally larger than those cooled by water. The peak and ultimate compressive strains of both carbonated and uncarbonated concrete specimens increase after heating, but the values of the latter are greater than that of the former. Finally, the constitutive equation to predict the compressive behaviors of carbonated concrete after high temperatures was established and validated by tests.

scholarly journals Effect of Temperature, Water Activity and Carbon Dioxide on Fungal Growth and Mycotoxin Production of Acclimatised Isolates of Fusarium verticillioides and F. graminearum

Toxins ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 478 ◽  
Author(s):  
Ladi Peter Mshelia ◽  
Jinap Selamat ◽  
Nik Iskandar Putra Samsudin ◽  
Mohd Y. Rafii ◽  
Noor-Azira Abdul Mutalib ◽  
...  
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Elevated Temperature ◽  
Water Activity ◽  
Fusarium Verticillioides ◽  
Fumonisin B1 ◽  
Fungal Growth ◽  
Effect Of Temperature ◽  
Mycotoxin Production ◽  
Co2 Levels

Climate change is primarily manifested by elevated temperature and carbon dioxide (CO2) levels and is projected to provide suitable cultivation grounds for pests and pathogens in the otherwise unsuitable regions. The impacts of climate change have been predicted in many parts of the world, which could threaten global food safety and food security. The aim of the present work was therefore to examine the interacting effects of water activity (aw) (0.92, 0.95, 0.98 aw), CO2 (400, 800, 1200 ppm) and temperature (30, 35 °C and 30, 33 °C for Fusarium verticillioides and F. graminearum, respectively) on fungal growth and mycotoxin production of acclimatised isolates of F. verticillioides and F. graminearum isolated from maize. To determine fungal growth, the colony diameters were measured on days 1, 3, 5, and 7. The mycotoxins produced were quantified using a quadrupole-time-of-flight mass spectrometer (QTOF-MS) combined with ultra-high-performance liquid chromatography (UHPLC) system. For F. verticillioides, the optimum conditions for growth of fumonisin B1 (FB1), and fumonisin B2 (FB2) were 30 °C + 0.98 aw + 400 ppm CO2. These conditions were also optimum for F. graminearum growth, and zearalenone (ZEA) and deoxynivalenol (DON) production. Since 30 °C and 400 ppm CO2 were the baseline treatments, it was hence concluded that the elevated temperature and CO2 levels tested did not seem to significantly impact fungal growth and mycotoxin production of acclimatised Fusarium isolates. To the best of our knowledge thus far, the present work described for the first time the effects of simulated climate change conditions on fungal growth and mycotoxin production of acclimatised isolates of F. verticillioides and F. graminearum.

The recovery of Gibberella zeae from wheat straws

1968 ◽  
Vol 8 (32) ◽  
pp. 364 ◽  
Author(s):  
LW Burgess ◽  
DM Griffin
Keyword(s):  
Microbial Activity ◽  
High Temperatures ◽  
Soil Fungus ◽  
Gibberella Zeae ◽  
Moist Soil ◽  
Different Temperatures

Attempts were made to recover Gibberella zeae (Schw.) Petch, a soil fungus which attacks wheat, from wheat straws colonized by the fungus and subsequently exposed in contact with soil at different temperatures and soil moistures. In certain treatments, the fungus could still be recovered after two years. In general, however, recovery declined with time and was adversely affected when the straws were exposed to conditions favouring increased microbial activity (moist soil at relatively high temperatures).

scholarly journals On a formula for the elastic force of vapour at different temperatures

1851 ◽  
Vol 5 ◽  
pp. 738-740
Keyword(s):  
High Temperatures ◽  
Low Temperatures ◽  
Elastic Force ◽  
French Academy ◽  
Different Temperatures ◽  
Series Of Experiments ◽  
Better Than

The author adopts as the basis of his formula the first series of experiments at high temperatures made by the French Academy, and those of Magnus at low temperatures. For the Academy’s experiments, he adopts the indications of the smaller thermometer in the steam in preference to those of the larger thermometer in the water. Of Dr. Young’s sort of formulae, he notices that of the Aca­demy and several others with exponents varying from 5 to 7. From the elasticity at freezing, as given by Magnus, compared with four of the Academy’s experiments, he shows that for the range of observation the number 6 is preferable to 5 as an exponent; but, as he states, no formula of this sort with a constant index can be found to agree with the observations throughout. The formula of Magnus he finds to agree with these observations better than any of the others; but being adapted to the air-thermo­meter, and therefore not convenient for ordinary use, he gives his own formula adapted to the mercurial thermometer, t = 500 + 225 log A / 5 - log A, t being the temp. Cent., and A the elasticity in atmospheres of 0 m .76 at zero, or 30 inches at 58° Fahr.; the temperature being given, the formula becomes log A = 5 - 1625 / 225 + t .

Persistent, vertical-migration rhythms in benthic microflora.: II. Field and Laboratory Studies On Diatoms From The Banks Of The River Avon

1966 ◽  
Vol 46 (1) ◽  
pp. 191-214 ◽  
Author(s):  
F. E. Round ◽  
J. D. Palmer
Keyword(s):  
High Temperatures ◽  
Vertical Migration ◽  
Laboratory Experiments ◽  
Biological Clock ◽  
Diatom Species ◽  
Laboratory Studies ◽  
Natural Conditions ◽  
Constant Illumination ◽  
Different Temperatures ◽  
Clock Hypothesis

The vertical migration of two Euglena species and several diatom species into and out of the sediment on the banks of the River Avon has been studied under natural conditions. All species have been shown to migrate vertically upwards when exposed during daylight. Tidal flooding of the sediment is generally preceded by re-burrowing of the algae beneath the surface. Methods have been devised to follow these migrations in both the field and laboratory. Laboratory experiments show that these migrations are rhythmic, continuing under constant illumination and temperature and removed from tidal influence. The effect of three different temperatures and three different light intensities has been investigated. Transfer from low to high temperatures has been shown to reset the phase of the rhythm. The results are discussed in relation to other work and to the ‘biological clock’ hypothesis.

ASSESSMENT OF THE POSSIBILITIES FOR PLACEMENT OF POPULATION’S MONEY

2019 ◽  
pp. 34
Author(s):  
Anastasija Jeršova
Keyword(s):  
Maximum Level ◽  
Financial Instruments ◽  
Maximum Benefit ◽  
The Future

The income of inhabitants can be not only consumed but also deposited or diverted to investments which can be made by using one or several money placement possibilities. This article deals with four money placement possibilities: deposits offered by banks, transactions with financial instruments, financing platforms and transactions with cryptocurrency. During the research was investigated how to calculate the amount of the provisional income, thus clarifying which placement possibilities are worth to choose for getting the maximum benefit in the future. The provisional amount of the income depends on the influence of the several factors; if an investor foresees them he will get the maximum level of the benefit in the future.

Decreased marine dimethyl sulfide production under elevated CO2 levels in mesocosm and in vitro studies

2012 ◽  
Vol 9 (4) ◽  
pp. 399 ◽  
Author(s):  
Valia Avgoustidi ◽  
Philip D. Nightingale ◽  
Ian Joint ◽  
Michael Steinke ◽  
Suzanne M. Turner ◽  
...  
Keyword(s):  
Human Activities ◽  
Dimethyl Sulfide ◽  
Marine Organisms ◽  
In Vitro Studies ◽  
Structural Components ◽  
Seawater Ph ◽  
Co2 Levels ◽  
The Future ◽  
Climate Cooling

Environmental contextAs atmospheric CO2 levels rise due to human activities, more of the gas dissolves in the oceans, increasing their acidity. The effect of these seawater changes on marine organisms is largely unknown. We examine the consequences of higher CO2 levels on the production by plankton of dimethyl sulfide, a climatically active gas. We find that higher CO2 levels leads to lower concentrations of dimethyl sulfide in the seawater, which has potentially important implications for the future climate. AbstractThe oceans have absorbed approximately half of the CO2 produced by human activities and it is inevitable that surface seawaters will become increasingly acidified. The effect of lower pH on marine organisms and ocean–atmosphere exchanges is largely unknown but organisms with CaCO3 structural components are likely to be particularly affected. Because calcifying phytoplankton are significant producers of dimethyl sulfide (DMS), it is vital to understand how lower seawater pH may affect DMS production and emission to the atmosphere. Here we show, by mesocosm (Raunefjorden, Norway, April–May 2003) and in vitro studies, that the net production of DMS and its cellular precursor dimethylsulfoniopropionate (DMSP) is approximately halved in microbial communities subjected to doubled CO2 levels. Our findings provide evidence that the amount of DMS entering the atmosphere could decrease in the future. Because atmospheric oxidation of DMS can lead to climate cooling by increasing cloud albedo, a consequence of reduced DMS emissions from a lower pH ocean would be an enhancement in global warming.

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