scholarly journals Biochemical Effects of Two Pesticides in Three Different Temperature Scenarios on the Diatom Thalassiosira weissflogii

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1247
Author(s):  
Andreia F. Mesquita ◽  
Fernando J. M. Gonçalves ◽  
Carolina P. Rocha ◽  
João C. Marques ◽  
Ana M. M. Gonçalves
Keyword(s):  
Growth Rate ◽  
Copper Sulfate ◽  
Nutritive Value ◽  
Climatic Changes ◽  
Marine Diatom ◽  
Main Concern ◽  
Trophic Chain ◽  
Thalassiosira Weissflogii ◽  
Different Temperatures ◽  
Aquatic Food

The exponential increase of the human population demands the overuse of fertilizers and pesticides in agriculture practices to suppress food production needs. The excessive use of these chemicals (fertilizers and pesticides) can comport deleterious effects to the ecosystems, including aquatic systems and communities. Oxyfluorfen is a fluorine-based herbicide, and its application has increased, since it is seen as an alternative to control glyphosate-resistant weeds. Copper sulfate is an inorganic pesticide based on copper which is being used in several chemical formulations, and it is the second main constituent of fungicides. Besides the known effects of such products in organisms, climatic changes pose an additional issue, being a main concern among scientists and politicians worldwide, since these alterations may worsen ecosystems’ and organisms’ sensitivity to stress conditions, such as the exposure to pollutants. Thalassiosira weissflogii (Grunow) G. A. Fryxell & Hasle, 1977 plays an important role in aquatic food webs as a primary producer and an essential food source to zooplankton. Thus, alterations on the diatom’s abundance and nutritional value may lead to consequences along the trophic chain. However, few studies have evaluated the biochemical impacts of oxyfluorfen and copper sulfate exposure on diatoms. This study intends to (1) evaluate the effects on the growth rate of both contaminants on T. weissfloggi at three temperatures, considering the actual scenario of climatic changes, and (2) assess biochemical changes on the diatom when exposed to the chemicals at different temperatures. To achieve these aims, the marine diatom was exposed to the two chemicals individually at different temperatures. The results showed an increase in the growth rate with increasing temperatures. Oxyfluorfen exhibited higher toxicity than copper sulfate. At the biochemical level, the microalgae were greatly affected when exposed to oxyfluorfen at 20 °C and 25 °C and when exposed to copper sulfate at 15 °C. Moreover, a general increase was observed for the polysaccharide content along the copper sulfate and oxyfluorfen concentrations. Therefore, the contaminants show the ability to interfere with the diatom growth and the nutritive value, with their effects dependent on the temperature.

scholarly journals Response of the marine diatom Thalassiosira weissflogii to iron stress1

1986 ◽  
Vol 31 (5) ◽  
pp. 989-997 ◽  
Author(s):  
Gail I. Harrison ◽  
F. M. M. Morel
Keyword(s):  
Marine Diatom ◽  
Thalassiosira Weissflogii

scholarly journals Effects of light intensity and temperature on Cylindrospermopsis raciborskii (Cyanobacteria) with straight and coiled trichomes: growth rate and morphology

2012 ◽  
Vol 72 (2) ◽  
pp. 343-351 ◽  
Author(s):  
MC. Bittencourt-Oliveira ◽  
B. Buch ◽  
TC. Hereman ◽  
JDT. Arruda-Neto ◽  
AN. Moura ◽  
...  
Keyword(s):  
Growth Rate ◽  
Light Intensity ◽  
Morphological Changes ◽  
Population Control ◽  
Distinct Species ◽  
Cylindrospermopsis Raciborskii ◽  
Climatic Chamber ◽  
Light Intensities ◽  
Different Temperatures ◽  
Lower Temperature

Cylindrospermopsis raciborskii (Woloszynska) Seenayya et Subba Raju (Ordem Nostocales) is one of the most troublesome bloom-forming species in Brazil. Understanding the population dynamics of the different morphotypes of C. raciborskii (straight and coiled) could assist in the prediction of favourable conditions for the proliferation of this potentially toxin-producing species. The aim of the present study was to assess the effects of two different light intensities and temperatures on the growth rate and morphology of the trichomes of the straight and coiled morphotypes. For such, two non-toxin producing strains of C. raciborskii were used - one with a coiled trichome (ITEP31) and another with a straight trichome (ITEP28). The strains were cultured in BG-11 medium in a climatic chamber under controlled conditions. Two light intensities (30 and 90 µmol.m-2.s-1 ) were combined at temperatures of 21 and 31 °C and the growth rate and morphological changes were analysed. The morphotypes responded differently to the different temperatures and light intensities. Both strains exhibited faster growth velocities when submitted to higher light intensity and temperature. The lower temperature and higher luminosity hampered the development of both strains. Variations in cellular morphology and an absence of akinetes in both strains were related to the lower temperature (21 °C). The coiled morphotype demonstrated considerable phenotype plasticity, changing the morphology of trichome throughout its growth curve. Although molecular analysis does not sustain the separation of the morphotypes as distinct species, their different eco-physiological responses should be considered further knowledge of extreme importance for the population control of these potentially toxic organisms.

scholarly journals Characteristics оf growth and fluorescence оf certain types оf algae under acclimation to different temperatures under conditions оf cultures

2019 ◽  
Vol 59 (3) ◽  
pp. 347-359
Author(s):  
A. I. Akimov ◽  
E. S. Solomonova
Keyword(s):  
Growth Rate ◽  
Positive Temperature ◽  
Tolerance Zone ◽  
Lower Growth ◽  
Culture Collections ◽  
Thermal Growth ◽  
Different Temperatures ◽  
Temperature Rate ◽  
Relative Variable ◽  
Stable Growth

The temperature rate growth dependence and the relative variable fluorescence, (Fv/Fm) of some of marine planktonic algae from the culture collections were investigated. The algae optima temperature growth (Topt), upper and lower limits tolerant zone of species, and in some cases, changes in the dynamics of these parameters outside the tolerance zone were determined. The similarity of species temperature characteristics with vegetation conditions these species in the nature was observed. Prolonged stress exposure to low positive temperature (4–6°C) was reversible; recovery of the growth rate and Fv/Fm was observed immediately after the increase of temperature. At temperatures above Topt on 2–3°C for diatoms was observed gradual degradation of culture, which, depending on the duration of exposure can lead to the death of the algae. Dinoflagellate species of the summer growing season had higher temperature resistance, and remained viable at temperatures above 5–8°C high Topt, due to lower growth rates. Rising part temperature dependence of the rate of growth approximated by a linear relation, the regression coefficient is 0.08–0.13 for diatoms and 0.03–0.11 for dinophyte. The normalized values for this parameter (the relative value of change in the growth rate, %) was 5.3±0.4 for diatoms and 6.4±0.5 for dinophyte at 1°C of temperature change. For dinophyte species were also been observed larger values of the parameter Q10. The value Fv/Fm for most species had high values in the whole temperature range, in which maintained a stable growth of algae. The fall of this parameter was observed in increasing the border of tolerance zone, and was associated with inhibition of thermal growth processes.

scholarly journals Performance of fat snook juveniles reared at different temperatures

2018 ◽  
Vol 40 (1) ◽  
pp. 39766
Author(s):  
Daniel Correia ◽  
Luiz Henrique Castro David ◽  
Sara Mello Pinho ◽  
João Costa-Filho ◽  
Maurício Gustavo Coelho Emerenciano ◽  
...  
Keyword(s):  
Growth Rate ◽  
Weight Gain ◽  
Specific Growth ◽  
Survival Rates ◽  
Feeding Rates ◽  
Feed Conversion ◽  
Final Weight ◽  
Different Temperatures ◽  
Water Recirculation ◽  
Fat Snook

We aimed at evaluating the effects of different water temperatures on the zootechnical performance of fat snook. The experiment lasted for 60 days, which was conducted in water recirculation systems, and was randomly designed with three treatments and three replicates each, corresponding to three water temperatures (25, 28 and 31°C). A total of 225 fat snook juveniles with a mean weight of 6.45 ± 0.58 g were used, which were fed daily until apparent satiety. Zootechnical parameters were assessed and feeding rates were registered for each tested temperature. Survival rates varied from 96 to 100% among treatments. Higher values of standard and total length, and weight gain were found in 28 and 31°C (p < 0.05). With regard to final weight, final biomass, feed conversion and specific growth rate, no significant differences were observed (p > 0.05). Feeding rates did not differ among evaluated temperatures. The results show that the used temperatures did not negatively affect zootechnical performance of fat snook juveniles. 

Growth Kinetics of Salmonella Isolates in a Laboratory Medium as Affected by Isolate and Holding Temperature†

1998 ◽  
Vol 61 (8) ◽  
pp. 964-968 ◽  
Author(s):  
THOMAS P. OSCAR
Keyword(s):  
Growth Rate ◽  
Stationary Phase ◽  
Growth Kinetics ◽  
Brain Heart Infusion ◽  
Lag Time ◽  
Culture Collection ◽  
Subsequent Growth ◽  
Laboratory Medium ◽  
Different Temperatures ◽  
Holding Temperature

Salmonella isolates were surveyed for their growth kinetics in a laboratory medium for the purpose of identifying isolates suitable for modeling experiments. In addition, the effect of holding stationary phase Salmonella cultures at different temperatures on their subsequent growth kinetics was evaluated for the purpose of developing a protocol to prevent the need for midnight sampling in modeling experiments. In Experiment 1, 16 isolates of Salmonella, 2 from the American Type Culture Collection (ATCC) and 14 from broiler operations, were surveyed for their growth kinetics in brain heart infusion (BHI) broth at 40°C. Lag time (P = 0.005) and growth rate (P = 0.022) were affected by identity of the isolate. Lag time ranged from 0.73 to 1.38 h, whereas growth rate ranged from 0.78 to 0.94 log10 CFU/ml/h. Overall, isolate S1 (Salmonella infantis from ATCC) was the fastest growing. In Experiment 2, 4 isolates of Salmonella, 1 from ATCC and 3 from broiler operations, were used to determine whether holding temperature influences subsequent growth kinetics. Salmonella isolates were grown to stationary phase at 37°C in BHI and then held for 24 h at 5, 22, or 37°C before dilution and reinitiation of growth in BHI at 37°C. Holding temperature did not alter or interact with identity of the isolate to alter subsequent growth kinetics. From the latter finding, a protocol was devised in which a dual-flask system is used to prevent the need for midnight sampling in modeling experiments. Similar to the results obtained in Experiment 1, identity of the isolate had only minor effects on growth kinetics in Experiment 2 indicating that all isolates examined were suitable for modeling experiments.

scholarly journals Detoxification of a toxic variety of Jatropha curcas using heat and chemical treatments, and preliminary nutritional evaluation with rats

2003 ◽  
Vol 21 (1) ◽  
pp. 51 ◽  
Author(s):  
E. M. Aregheore ◽  
K. Becker ◽  
H.P.S. Makkar
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Food Intake ◽  
Jatropha Curcas ◽  
Nutritive Value ◽  
Body Weight Loss ◽  
Casein Diet ◽  
Sprague Dawley ◽  
Chemical Treatments ◽  
Diet Control

Seeds from a toxic variety of Jatropha curcas (Capo Verde, Nicaragua) were processed, defatted and ground to obtain the meal. The meal was subjected to heat and 14 different chemical treatments to detoxify the meal of lectin and phorbolesters. Heat treatment inactivated lectin, but not phorbolester. One of the treatments reduced phorbolesters to a tolerable level of 0.09 mg/g. The treated meals with other ingredients were used in diets to assess acceptance and nutritive value of detoxified Jatropha curcas meal in two experiments. Experiments 1 and 2 had twelve (12) male weanling rats each, Sprague Dawley strain, 28-30 days old, pre-experimental average body weights of 8379±7.2 and 84.6±6.4 g, respectively. They were divided into three groups according to body weight and fed casein diet (control) and two diets in which Jatropha curcas was the protein source. In experiment 1, the rats accepted diet 1, but did not fully accept diet 2. Food intake, growth rate, protein efficiency ratio (PER) and food transformation index (T1) were significantly better (P<0.05) in diet 1 than in the casein and diet 2. In experiment 2, casein diet was better (P<0.05) in food intake, growth rate, PER and TI than diets 1 and 2. Food intake with Jatropha meal was significantly reduced and the rats had drastic body weight loss (P<0.05) and this might be due to the presence of phorbolesters in the diets. Generally, the presence of phorbolesters in food has significant effect on its acceptance. Jatropha meal obtained from treatment 3 had a crude protein (CP) content of 68%, far higher than the CP content of most oilseed meals (soyabean). This treatment seems a better method of detoxifying Jatropha curcas meal for livestock but in economic terms it is expensive to produce a meal from it.

scholarly journals Enhancing Algal Growth by Stimulation with LED Lighting and Ultrasound

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Shao-Yi Hsia ◽  
Shiuh-Kuang Yang
Keyword(s):  
Growth Rate ◽  
Algal Growth ◽  
Ultrasound Treatment ◽  
Health Food ◽  
Led Lighting ◽  
Natural Factors ◽  
Potential Market ◽  
Different Temperatures ◽  
Biomechanical Stimulation ◽  
Led Lights

Algae are not only rich in natural nutrients, but are also a high-priced health food. An important constituent called “growth factor” is extracted from algae and used as an ingredient in medical drugs, foods, cosmetics, and other products. Its enormous potential market should not be taken lightly. Algae are mostly found near coastal areas and their habitats are limited by a number of natural factors, leading to large labor and financial expenditures to harvest. This report describes our study of indoor algae production using LED lights and ultrasound and manipulating other growth factors at different temperatures. Ultrasound treatment at the alga’s natural resonant frequency was varied to determine optimal algal growth using the Taguchi method to plan and to analyze the experiments. The results were very satisfying, showing an 8.23% increase in the growth rate by the fifth day due to ultrasound treatment and an amazing 27.01% growth rate due to biomechanical stimulation.

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