Effects Of Nutritional Conditions Research Articles

How Trophic Conditions Affect Development of Fire Salamander (Salamandra salamandra) Larvae: Two Extreme Cases

Reduced trophic resources can pose relevant constraints to the development of freshwater animals with complex life cycles. For amphibians, food deprived environments, such as high-altitude ponds and springs and groundwaters are frequently used for breeding. The aim of this study is to outline trophic conditions leading to extreme cases of delayed larval development and increased size at metamorphosis of a European widespread amphibian, the fire salamander (Salamandra salamandra). We collected 150 fire salamander larvae, split them in two groups, one with high and one with low trophic resource availability. We then observed the effects of nutritional conditions on larval development recording time to metamorphosis and average day growth. Moreover, in the field, we surveyed larvae growth and size at metamorphosis in two artificial subterranean sites with low prey availability. Trophic conditions strongly affected larval development and under low food treatment time to metamorphosis reached up to 416 days. In the subterranean environments we observed a similar pattern, with larvae requiring more than one year to attain metamorphosis but reaching unexpected large sizes. Environmental trophic conditions experienced during early stages can induce strong delay in metamorphosis of the fire salamander; this plasticity makes fire salamander larvae optimal models for comparative studies and cross-environment experiments.

Nutritional Regulation of Mammary Tumor Microenvironment

The mammary gland is a heterogeneous organ comprising of immune cells, surrounding adipose stromal cells, vascular cells, mammary epithelial, and cancer stem cells. In response to nutritional stimuli, dynamic interactions amongst these cell populations can be modulated, consequently leading to an alteration of the glandular function, physiology, and ultimately disease pathogenesis. For example, obesity, a chronic over-nutritional condition, is known to disrupt homeostasis within the mammary gland and increase risk of breast cancer development. In contrast, emerging evidence has demonstrated that fasting or caloric restriction can negatively impact mammary tumorigenesis. However, how fasting induces phenotypic and functional population differences in the mammary microenvironment is not well understood. In this review, we will provide a detailed overview on the effect of nutritional conditions (i.e., overnutrition or fasting) on the mammary gland microenvironment and its impact on mammary tumor progression.

The effect of nutritional condition by two nucleic acid derived indices on the growth to post-flexion of Atlantic bluefin tuna and Atlantic bonito larvae

Notochord flexion increases the swimming capacity of fish larvae, aids in the capture of mobile prey, and coincides with the timing of when the physiological capacities of larvae begin to develop significantly, allowing an early shift to piscivory. Therefore, reaching the flexion stage as soon as possible can be considered beneficial for the growth and survival of the larvae. Individual growth differences of larvae from the same cohort are very common before reaching flexion and the potential explanation is still unknown. In this study, we examined if the nutritional status of the larvae, measured by the RNA:DNA and DNA:DW ratios, explains the differences in the development of notochord flexion in laboratory-reared Atlantic bluefin tuna (ABFT; Thunnus thynnus) and Atlantic bonito (AB; Sarda sarda) larvae. Moreover, we described the ontogeny of the different stages and condition indices. The daily average condition of ABFT estimated by the RNA:DNA and DNA:DW ratios increased with larval age and developmental stage, whereas in AB it was not. In both species, bigger larvae at a specific age had higher nutritional condition than smaller larvae regardless of developmental stage. However, in ABFT the DNA:DW ratio indicated lower condition for the biggest larvae within developmental stages F0 (pre-flexion) and F3 (post-flexion). After removing the size effect, larger individuals of ABFT within flexion stages F1 and F2 had higher condition than any other larval stages, whereas in AB an indistinct trend within stages was found. Our results confirm that in ABFT the RNA:DNA ratio is correlated with faster development while the DNA:DW ratio is negatively correlated with the time to flexion. The trends found in the DNA:DW ratio points at cell growth mechanisms being a better indicator of larval condition that the RNA:DNA ratio. Our findings suggest that under culture, ad libitum conditions, larval nutritional conditions measured by nucleic acid ratios, might not be enough to explain developmental differences in fast growing species.

Tick infestations correlates at a Falkland Islands Black-browed Albatross colony

The tick Ixodes uriae is an ectoparasite widely distributed among seabirds throughout circumpolar regions, usually associated with seabird colonies. Nevertheless, potential effects of infestations, especially in chicks, are not well documented. In this article, we studied factors associated with probability and intensity of infestations in Black-browed Albatross Thalassarche melanophrys nestlings in a colony at the Falklands Islands. We compared the body measurements, physiological parameters, distance to other nests and position inside the colony between infested and non-infested 40 Black-browed Albatross nestlings. Ticks were present in 60% of the nestlings with a mean number per nestlings of 1.47. None of the 12 analysed blood parameters but LDH (Lactate dehydrogenase) showed significant differences between infested and not infested nestlings. Nestlings infected showed significant higher level of LDH than those without ticks. The number of ticks found on each nestling was positively and significantly correlated with their LDH blood levels. Tarsus length (as a proxy of age) and distance to the nearest nest showed a significant effect, with younger nestlings with closer nests showing higher probability to be infected. These variables also affect intensity of infestation. No effects of nutritional condition (butyrate or urea levels) or body condition (residuals of cubic root of mass/tarsus length regression) on probability or intensity of infestation were found. Both small anaemias and tick scars would explain the different values of LDH between infected/non-infected chicks. The low level of infestation found in our colony could be the cause of a non-detectable effect of the presence of ticks on nestling body condition and other blood parameters related to metabolism of fat or protein.

Effects of nutritional conditions on lipid production by cyanobacteria.

The present study evaluated the effects of the culturing media and the levels of nitrogen and phosphorus on the growth, biomass productivity and lipid production of four species of Microcystis (M. novacekii, M. aeruginosa, M panniformis and M. protocystis). The lipid extract was obtained by refluxing with dichloromethane (Soxhlet). The biomass and biomass productivity yields were maximized with ASM-1 medium treatment enriched with nitrogen and/or phosphorus (0.25-0.65 g/L and 25-50.7 mg/L d-1, respectively). The lipid extract yields from M. panniformis and M. novacekii were inversely correlated with the concentration of nitrogen and directly correlated with the concentration of phosphorus (35.8 % and 31.7 %). The lipid extract yield from M. aeruginosa was inversely correlated with the nutrient concentration (23.3 %). M. protocystis exhibited a higher lipid content in the control medium (41.5 %) than in the nitrogen-enriched media. The recorded results show that a nutrient-poor culture medium favours cell growth and stimulates lipid accumulation, which directly affects the cost of cultivation by reducing nutrient consumption. All studied species may serve as biomass sources for biodiesel production, although M. protocystis exhibited the highest lipid production. Further studies are necessary to determine the composition of the recorded lipid extract.

Production of poly-β-hydroxybutyrate by activated sludge in sequencing batch reactor under aerobic conditions

In order to improve poly-β-hydroxybutyrate (PHB) production in activated sludge, the anaerobic/aerobic alternative operating sequencing batch reactor (SBR) process was applied in this paper to accumulate PHB. Effects of nutritional conditions and carbon concentration on PHB accumulation were studied. Results indicated that PHB accumulation reached the highest level and accounted for 11.2 % under anaerobic condition for phosphate limitation and 20.84 % under aerobic condition for nitrogen and phosphate limitation of mixed liquor suspended solid (MLSS), respectively. In addition, 4 g/L was proved to be the optimum carbon concentration in both anaerobic and aerobic experiments, and the PHB accumulation reached 17.1 % (anaerobic, phosphorus limitation) and 60.4 % (aerobic, nitrogen and phosphorus limitation) of MLSS, respectively. PHB could be successfully extracted with sodium hypochlorite and chloroform method from the activated sludge. In addition, the infrared spectrum showed that the PHB sample extracted was of high purity.

Effects of nutritional conditions on growth and biochemical composition of Tetraselmis sp.

BackgroundThis study aimed to maximize biomass concentration, biomass productivity and biochemical composition of the marine microalga Tetraselmis sp.MethodsIn the current study, Box-Behnken Design was used to model the effect of NaNO3, NaH2PO4, metals and vitamins in the F/2 medium on the growth, total chlorophylls, carotenoids and starch contents. The total chlorophylls content was quantified by spectrophotometry. The FT-IR spectroscopy was used to estimate the biochemical compositions of Tetraselmis sp. grown under both optimized medium culture for starch production and standard culture medium.ResultsFinalized NaNO3 (1.76 mM), NaH2PO4 (0.018 mM), metals (1500 μL.L−1) and vitamins (312.5 μL.L−1) concentrations, generated an increase in biomass concentration up to 5.72 g.L−1 which contributed to an increase about 2.4-fold than that of the standard conditions of biomass productivity (408.57 mg.L−1.day−1). The maximum value of carotenoids content (0.3 mg.g DW−1) was achieved at the highest level of all factors. The total chlorophylls content reached also its maximum (5.18 mg.g DW−1) at high nitrate (1.76 mM), phosphate (0.054 mM), metals and vitamins concentrations, while the maximum starch content (42% DW) was achieved with low nitrate and phosphate concentrations (0.58 mM and 0.027 mM) and with metals and vitamins limitations. Thus, the nitrogen, phosphorus, metals and vitamins limitations led to divert the metabolism for the starch biosynthesis.ConclusionsThe high biomass concentration productivity and starch production make Tetraselmis sp. strain a good candidate for biotechnological applications.

Larval and adult nutrition effects on reproductive traits in the red flour beetle

AbstractVariation in individual condition is probably one of the most critical factors affecting the high levels of diversity in animal fitness components, commonly observed in natural populations. Differential access to nutritional resources, in turn, is among the most important determinants of condition. However, our understanding of how resource access at different stages of life cycle shapes animal traits is still far from comprehensive. Here, we analyzed how larval and adult diet affects key reproductive components of males (mating activity) and females (fecundity) in red flour beetles Tribolium castaneum. Furthermore, we used path analysis to investigate whether the effects of nutritional conditions are mediated by body mass. In males, we found that juvenile, but not adult diet affected mating performance, with males developing on rich diet as larvae achieving higher mating success. In females, on the other hand, these effects interacted: malnutrition at larval stage led to fecundity decline, which was partially alleviated if dietary conditions were improved at the adult stage. Interestingly, the effects of diet on reproductive traits were mostly independent of body mass. These results suggest that larval nutrition may influence reproduction via effects on composition, rather than size, of the adult body.

Effects of Nutritional Conditions on the Stable Carbon and Nitrogen Isotope of Microalgae

Carbon and nitrogen stable isotopes were studied among different groups and species of marine phytoplankton on the aspect of growth phase and nutrient conditions. Three investigated algal species which represent the Chlorophyceae, Dinophyceae and Desmokontae classes were grown in batch monocultures and analysed for δ13C and δ15N in both exponential and stationary phase. For all the cultured species, δ13C signatures range from 24.77 (A.carterae) to 17.10 (P. micans) as well as δ15N range from-15.66(P. helgolandica) to 14.40(P. helgolandica).These three species (Platymonas helgolandicavar. tsingtaoensis,Amphidinium carteraeHulburt andProrocentrum micans) were also grown under nutrient sufficient and nitrogen or phosphorus deficient conditions. Nitrogen limitation resulted in a more negative δ13C signature, whereas no effect could be observed during phosphorus limitation compared to nutrient sufficient conditions. But nitrogen and phosphorus limitation resulted in a more positive δ15N signature. The results show that the carbon and nitrogen isotopic signature of phytoplankton may be differ among different phytoplankton species, between exponential and stationary phase, as well as between nutrient treatments.

Effects of Nutritional Conditions on the Stable Carbon and Nitrogen Isotope of Microalgae

Carbon and nitrogen stable isotopes were studied among different groups and species of marine phytoplankton on the aspect of growth phase and nutrient conditions. Three investigated algal species which represent the Chlorophyceae, Dinophyceae and Desmokontae classes were grown in batch monocultures and analysed for δ13C and δ15N in both exponential and stationary phase. For all the cultured species, δ13C signatures range from 24.77 (A.carterae) to 17.10 (P. micans) as well as δ15N range from-15.66(P. helgolandica) to 14.40(P. helgolandica).These three species (Platymonas helgolandicavar. tsingtaoensis,Amphidinium carteraeHulburt andProrocentrum micans) were also grown under nutrient sufficient and nitrogen or phosphorus deficient conditions. Nitrogen limitation resulted in a more negative δ13C signature, whereas no effect could be observed during phosphorus limitation compared to nutrient sufficient conditions. But nitrogen and phosphorus limitation resulted in a more positive δ15N signature. The results show that the carbon and nitrogen isotopic signature of phytoplankton may be differ among different phytoplankton species, between exponential and stationary phase, as well as between nutrient treatments.

Recent Advances in Microbial Metal Bioaccumulation

Removal of hazardous metals through biological means has received considerable attention in the last few decades. Nevertheless, only a fraction of these studies employed growing microbial cells that harbor multiple mechanisms of metal sequestration and thus may hold greater metal uptake capacities. The authors summarize the studies concerning response of growing cells to metals toxicity in terms of growth rate, biomass production, and morphological/structural adaptations along with latest reports involving genomics and proteomics approach. The studies indicate bright potential of metal resistant strains or strains with hormesis phenomenon for field application. In the second part of the review they focuses on the effect of nutritional conditions and process parameters on metal removal capacities and the performance in simultaneous removal of multiple pollutants. Reports demonstrating effective treatment of actual industrial effluents using growing cells have been summarized. With ample evidence available on the success of growing cells in metal bioremediation, the development and testing of large scale industrial bioreactors is warranted.

Nutritional regulation of protease production by the feather-degrading bacterium Chryseobacterium sp. kr6

The effects of nutritional conditions on growth and protease production by the feather-degrading Chryseobacterium sp. kr6 were investigated. Higher growth was observed on feather-containing or tryptone (TR) medium when compared to casein (CA) or glucose-nitrogen (GN) base medium. Protease production occurred during growth on feather-containing and TR media, whereas no protease activity was detected on CA or GN medium, indicating that protease production is not constitutive, depending on the presence of specific complex nitrogen sources. Supplementation of whole feathers (WF) medium with glucose (WFG) or NH(4)Cl (WFN) did not result in major differences in growth and protease production, whereas soluble protein was lower in supplemented media. Glucose consumption and growth were higher on WFG than on GN medium, suggesting that the absence of a specific complex nitrogen source limited bacterial growth. On WF medium, this strain grew closely attached to the feather structures, initially on the barbules and subsequently on the feather rachis. It was observed, through zymogram analysis, that strain kr6 produced diverse proteolytic enzymes in response to different growth substrates. These results were confirmed by the differential behaviors of crude proteases towards protease inhibitors.

Effects of nutritional condition on spring migration: do migrants use resource availability to keep pace with a changing world?

Because of their reliance on temporally predictable resources across large spatial scales, migratory birds may be especially vulnerable to anthropogenic climate and land-use changes. Although some long-distance migrants appear unable to adjust to phenological shifts on their wintering grounds, several short- and medium-distance migrants appear to have altered the timing and/or distance of their yearly movements to compensate for the environmental effects of global warming. Which environmental cues are responsible for stimulating these adjustments is an unanswered question, although most studies have focused on weather conditions. Here, we present a novel field experiment that demonstrates that an alternative cue, food availability, may be a crucial link between local conditions on the wintering grounds and the timing of spring departure. When we provided dark-eyed juncos (Junco hyemalis) with an abundant food supply in early spring, we observed an advance in migration, especially among individuals that increased their mass and fat stores in response to the treatment. This finding indicates a simple mechanism by which short-distance migrants may calibrate their migration behavior such that arrival on the breeding grounds and initiation of reproduction are in sync with resource availability.

Effect of nutritional conditions on dye removal from textile effluent by Aspergillus lentulus

The nutritional conditions supporting growth and maximum dye removal by Aspergillus lentulus have been investigated. Initially a composite media containing yeast extract, glucose and mineral components was used and the effect of various components on dye removal was studied. For maximum dye removal (≈100%), ≥0.5% (w/v) glucose and ≥0.25% (w/v) yeast extract were essential. While glucose played an important role in pellet formation, which in turn was important for dye removal, yeast extract contributed towards higher biomass production. Mineral components (except NH4NO3) did not affect dye removal significantly. Next the alternate sources of carbon (molasses, jaggery, starch and sodium acetate) and nitrogen (peptone, urea, ammonium nitrate, sodium nitrate and ammonium chloride) were tested. Among carbon sources, all the sources produced almost complete dye removal in 48 h (more than 97% in 24 h), except sodium acetate (64% in 48 h). All the tested nitrogen sources resulted in >90% dye removal in 48 h. Yeast extract and peptone gave best results with high dye removal rate (9.8 and 8.1 mg/l/h, respectively). However, among the low cost alternates, urea and NH4Cl came out to be suitable sources due to the high uptake capacity of the biomass produced coupled with high dye removal rate in case of NH4Cl. Therefore, a combination of urea and NH4Cl was tested, which produced complete dye removal with a high dye removal rate (10 mg/l/h). Finally the modified composite media containing urea and NH4Cl as nitrogen sources and glucose as carbon source was utilized for effluent treatment. Results indicated that performance of modified composite media was at par with composite media for supporting growth of A. lentulus and dye removal from the textile effluent.

Impact of nutritional conditions on yields, germination rate and shelf-life of Plectosporium alismatis conidia and chlamydospores as potential candidates for the development of a mycoherbicide of weeds in rice crops

The effect of nutritional conditions on spore qualities was investigated in order to select which propagules, conidia or chlamydospores, would be most suitable for mycoherbicide development. Plectosporium alismatis was grown in a liquid basal medium supplemented with glucose and a mineral nitrogen source (sodium nitrate) or an organic nitrogen source (casamino acids). Conidial and chlamydospore yields, germination rate and shelf-life were compared. Two growth models were developed: on one hand, sodium nitrate added as the sole nitrogen source was partially utilised (8%), resulting in poor growth (1.77±0.02 mg mL−1; 6±1.7×105 conidia mL−1). Under these conditions, P. alismatis produced dense, melanised-like aggregates that contained chlamydospores (12.4±0.7×104 chlamydospores mL−1). Germination rates of chlamydospores and conidia produced under these conditions was high (80%). Twenty percent of chlamydospores were able to germinate after 4 months storage at 25°C, while survival of conidia declined rapidly (<2%). When casamino acids were added to the liquid medium as the sole nitrogen source, P. alismatis produced sparser pellets resulting in high dry weights (5.37±0.09 mg mL−1 and high conidia numbers (9.6±1.5×106 conidia mL−1), while no chlamydospore were observed. The germination rate of conidia produced in casamino acids was low (33±13%) after 8 h incubation and microcycle conidiation occurred. Five percent of these conidia germinated after 4 months storage. These data indicate that chlamydospores may be suitable for mycoherbicide development, provided further optimisation of yields is achieved.

Recovery from Swimming‐Induced Hypothermia in King Penguins: Effects of Nutritional Condition

We investigated changes in the rate of oxygen consumption (V O2) and body temperature of wild king penguins (Aptenodytes patagonicus) in different nutritional conditions during recovery after exposure to cold water. Over time, birds undertook an identical experiment three times, each characterized by different nutritional conditions: (1) having recently completed a foraging trip, (2) after fasting for many days, and (3) having been refed one meal after the fast. The experiments consisted of a 2-h session in a water channel followed by a period of recovery in a respirometer chamber on land. Refed birds recovered significantly more quickly than fed birds, in terms of both time to reach resting V O2 on land and time to reach recovery of lower abdominal temperature. Previous work found that when penguins are in cold water, abdominal temperatures decrease less in refed birds than in fed or fasted birds, suggesting that refed birds may be vasoconstricting the periphery while perfusing the gut region to access nutrients. This, alongside an increased resting [V O2], seems the most reasonable explanation for why refed birds recovered more quickly subsequent to cold-water exposure in this study; that is, vasoconstriction of the insulative periphery meant that they lost less heat generated by the body core.

Effects of food deprivation, body size, and egg load on the mating behavior of female Japanese beetles, Popillia japonica Newman (Coleoptera Scarabaeidae)

Female condition may play an important role in the mating frequency of species that mate at foraging areas. For example, in species where feeding females are more easily encountered or less resistant to mating than females that are performing other activities, low energy levels could increase mating activity. We studied the relationship between female condition and mating activity in the Japanese beetle, Popillia japonica (Coleoptera Scarabaeidae) in a laboratory study. We altered condition by depriving some females of food for one day and comparing their mating behavior to well-fed females. Our results showed that the effect of nutritional condition on mating behavior only became apparent when we considered female body size and fecundity status: well-fed, relatively large females, well-fed, relatively fecund females, and unfed, relatively small females mated more frequently than their counterparts. These patterns may be a result of food deprivation altering the costs and benefits of mating for females of different body sizes and egg loads, and perhaps reflect a need for females that are about to oviposit needing to maximize their food intake.

Effect of nutritional conditions on extracellular protease production by the haloalkaliphilic archaeon Natrialba magadii

The effect of various nitrogen sources and nutritional starvation was examined on the production of an extracellular protease secreted by the haloalkaliphilic archaeon Natrialba magadii. Cell growth and proteolytic activity were measured in cells grown with different nitrogen sources. Proteolytic activity was produced in complex and easily metabolized nitrogen sources such as yeast extract, casein and casamino acids; meanwhile, ammonium repressed enzyme production. The time course and amount of protease accumulated showed an inverse correlation with growth rate and nutrient concentration. Starvation did not induce extracellular protease production. The accumulation of Nab. magadii extracellular protease is stimulated by nutrient limitation and slow growth rate indicating that it is probably induced in response to a deficit in the energetic status of the cells. Nutritional starvation did not induce protease accumulation suggesting that de novo synthesis of this protease and/or factor/s necessary for its activation are required. This enzyme may be regulated by nitrogen catabolite repression and it does not require protein substrates for induction. These results contribute to the basic knowledge on protease regulation in haloalkaliphilic archaea and will help to optimize the production of this extremozyme for biotechnological applications such as protease-catalysed peptide synthesis.

Effects of long-term starvation on hepatocyte ultrastructure of olive flounder Paralichthys olivaceus

The effects of nutritional conditions on alterations in condition factor, liver-somatic index, and hepatocyte ultrastructure in the olive flounder Paralichthys olivaceus were examined. Twelve weeks of starvation significantly decreased the condition factor and the liver-somatic index in the olive flounder. Hepatocytes underwent marked ultrastructural changes in response to 12 weeks of starvation. Compared to those of the initial control and fed group, the prominent features characterizing the hepatocytes of the starved group were: reduction in cell and nucleus size; apparent loss of nucleoli; condensation of chromatin; loss of stored glycogen; reduction of endoplasmic reticulum profile; increase in the number of electron-dense bodies containing large amounts of iron; and increased mitochondrial size. Results suggest that the histological changes caused by ultrastructural alterations in the hepatocytes can be used as alternative indicators to identify starvation in cultured P. olivaceus.

Effect of Nutritional Status and Ozone Exposure on Some Biomarkers of Oxidative Stress in Rat Brain Regions

: The aim of this study was to analyze the effect of nutritional condition and simulated exposure to ozone on Glutathione (GSH), the activity of Na+/K+ ATPase and lipid peroxidation in rat brain. Male Wistar rats were fed with 7% and 23% protein diets. Two groups were formed for each nutritional condition: one group was exposed for 15 successive days to 0.75 ppm of ozone and the other to air. Subsequently, the brain was dissected in cortex, hemispheres, cerebellum, and brainstem to measure the activity of thiobarbituric acid reactive substances (TBARS), ATPase, and levels of GSH. The activity of Na+/K+ ATPase increased in cerebellum of well-nourished rats exposed to ozone, while total ATPase and TBARS decreased in all studied areas in the malnourished groups. The levels of GSH decreased significantly (P < 0.05) in the brain of rats fed with 7% of protein diet and exposed to ozone but increased in rats fed with normal diet and exposed to ozone. These results suggest that malnutrition causes alterations in the values of Na+/K+ ATPase, total ATPase, GSH, and lipid peroxidation, while ozone contributes to these modifications. As a consequence, both variables are involved in oxidative stress in the rat brain.