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Temperature and salinity are well-known environmental factors that affect the growth and biochemical composition of brown algae. In this study, we conducted a culture experiment to test the effects of temperature (10, 15, and 20 °C) and salinity (10, 20, 30, and 40 psu) on specific growth rates (SGR) and five compounds (carbon, nitrogen, chlorophyll (Chl) a, Chl c, and fucoxanthin) of Sargassum fusiforme, an ecologically and commercially important species. The results showed that both temperature and salinity had significant effects on SGR and the tissue contents of carbon and nitrogen. Maximal SGR of 6.04% day−1 was achieved at 20 °C and 30 psu. The highest tissue content of carbon (38.19 ± 1.01%) was obtained at 10 °C and 30 psu, while that of nitrogen (2.78 ± 0.09%) was at 15 °C and 10 psu. Significant positive effects of increased temperature were found on both Chl a and Chl c contents. A significant positive effect of increased salinity was only found on the Chl a content. The Chl a and Chl c contents were maximized at 0.50 ± 0.03 and 0.16 ± 0.03 mg g−1 at 15 °C and 20 psu. In addition, significant positive effect of increased temperature and significant negative effect of increased salinity were detected for the fucoxanthin content; this was at a maximum of 2.62 ± 0.04 mg g−1 at 15 °C and 10 psu. These physiological data provide valuable information related to the enhancement of S. fusiforme composition when in cultivation under controlled conditions.

Diatoms are eukaryotic microalgae that contain genes from various sources, including bacteria and the secondary endosymbiotic host. Due to this unique combination of genes, diatoms are taxonomically and functionally distinct from other algae and vascular plants and confer novel metabolic capabilities. Based on the genome annotation, we performed a genome-scale metabolic network reconstruction for the marine diatom Phaeodactylum tricornutum. Due to their endosymbiotic origin, diatoms possess a complex chloroplast structure which complicates the prediction of subcellular protein localization. Based on previous work we implemented a pipeline that exploits a series of bioinformatics tools to predict protein localization. The manually curated reconstructed metabolic network iLB1027_lipid accounts for 1,027 genes associated with 4,456 reactions and 2,172 metabolites distributed across six compartments. To constrain the genome-scale model, we determined the organism specific biomass composition in terms of lipids, carbohydrates, and proteins using Fourier transform infrared spectrometry. Our simulations indicate the presence of a yet unknown glutamine-ornithine shunt that could be used to transfer reducing equivalents generated by photosynthesis to the mitochondria. The model reflects the known biochemical composition of P. tricornutum in defined culture conditions and enables metabolic engineering strategies to improve the use of P. tricornutum for biotechnological applications.

The paper aims to compare parameters of lipid peroxidation and antioxidant defense system, as well as blood biochemical composition in infertile cows from groups that differ in terms of selenium content in agrocoenosis. Forty-five black-motley and red-motley breeds in each region were selected for the experiment; the groups were formed on the basis of the pathology, 15 animals each. The level of microelements in the blood of animals from all groups in the selenium-deficient biogeochemical province is significantly reduced by 38.4–41.7% (P < 0.05). In these cows, the concentration of malondialdehyde increased significantly, by 1.5–2.1 times (P < 0.05), against the background of decrease in the activity of glutathione antioxidant defense: glutathione peroxidase by 9.4–32.1% (P < 0.05), glutathione reductase by 2.4–2.6 times (P < 0.05), also superoxide dismutase and catalase in some groups. In the groups of infertile animals with lowered selenium content in blood, the author found an increase in enzymes’ activity (P < 0.05): alanine aminotransferase by 25.6–52.6%, aspartate aminotransferase by 17.8% in cysts and by 44.3% in ovarian hypofunction, gamma-glutamyltransferase by 18.3% in ovarian hypofunction. In addition, the calcium content in the blood of cows was reduced by 8.1–14.0% (P < 0.05) when selenium levels were lowered. In combination with elevated levels of urea and urea/creatinine ratio, the above may be evidence of pathological processes in muscle, liver, and kidney tissues. Thus, the author traced the dependence of the balance of lipid peroxidation and antioxidant defense system on the microelement level, as well as the effect of low selenium provision of animals in biogeochemical provinces on the biochemical composition of their blood.

Our understanding of ice algal responses to the recent changes in Arctic sea ice is impeded by limited field observations. In the present study, environmental characteristics of the landfast sea-ice zone as well as primary production and macromolecular composition of ice algae and phytoplankton were studied in the Kitikmeot Sea near Cambridge Bay in spring 2017. Averaged total chlorophyll-a (Chl-a) concentration was within the lower range reported previously for the same region, while daily carbon uptake rates of bottom-ice algae were significantly lower in this study than previously reported for the Arctic. Based on various indicators, the region's low nutrient concentrations appear to limit carbon uptake rates and associated accumulation of bottom-ice algal biomass. Furthermore, the lipids-dominant biochemical composition of bottom-ice algae suggests strong nutrient limitation relative to the distinctly different carbohydrates-dominant composition of phytoplankton. Together, the results confirm strong nitrate limitation of the local marine system.

This study aimed to systematically investigate and compare the biochemical composition of 13 locally abundant shellfish species (Dalian, China) and the taste characteristics of these shellfish and their boiling liquids. The results showed that Chlamys farreri exhibited the highest level of protein (64.58%) and polyunsaturated fatty acids (53.84% of total fatty acids), whereas Scapharca subcrenata showed a better composition and proportion of essential amino acids (EAA/TAA = 39.02%, EAA/NEAA = 63.98%) compared to other species. Glu, Gly, Ala, Arg, 5′-monophosphate (GMP), lactic acid, succinic acid, and malic acid were quantitatively determined as the main taste compounds in shellfish and their boiling liquids. The equivalent umami concentration (EUC) values, reflecting the synergistic effect of umami compounds, showed distinct characteristics, and the maximum umami intensities were found in Meretrix meretrix (586.8 g monosodium glutamate (MSG)/100 g) and the boiling liquid of Clinocardium californiense (358.3 g MSG/100 g), respectively. Based on these experimental results, C. californiense was found to have the highest prehensive quality score as revealed by principal component analysis (PCA). These results are important for promoting studies aimed at nutritional value development and taste compounds improvement of these shellfish species, especially for flavor enhancer development. Meanwhile, different shellfish species can be comprehensively developed and utilized based on their distinct nutritional properties, and this would translate into greater profitability for producers.

The edible milky mushroom is the most widely cultivated mushroom in tropical and sub-tropical regions. Studies were conducted on the cultivation and nutritional analysis of this mushroom. The pure culture of Calocybe indica was carried out in the laboratory. The culture was maintained on potato dextrose agar slant and sub-cultured at a regular monthly interval to sustain their fruiting vigor. The above stock culture was used in studies. Wheat grain spawn of C. indica was prepared in glass bottles. The filled paddy grain spawn of C. indica was used at 6% level to the wet weight of the substrate and the beds were spawned. After harvest, the mushrooms were dried at 40°C under the hot air oven to make it powered for further analysis. The collected fresh mushrooms were dried in shade and coarse powder was analyzed for nutrients namely moisture, crude protein, lipid, ash, crude fiber, and minerals. It shows the dominant compounds of protein, fiber, and carbohydrate and the contents are 14.11%, 8.30% and 5.62% respectively. Lipid, ash, ether extract and pH contents are 4.06%, 7.04%, 3.15% and 5.4% respectively. The carbon and nitrogen contents are 33.60% and 3.56% respectively. In the estimation of saturated fatty acids and unsaturated fatty acids present in C. indica, totally, 17 fatty acids were recorded. In the estimation of essential and non-essential amino acids present in C. indica, totally, 15 amino acids were recorded. In the estimation of minerals composition present in C. indica, it was recorded that the species had a good resource of mineral composition. Totally, 6 macro minerals and 8 micro minerals were recorded. This investigation may provide that the paddy straw substrates can be recommended for the commercial cultivation of C. indica to obtain highly nutritious mushrooms.

Due to their relevant ecological position and well-studied biology, sea urchins are reference organisms for ocean acidification studies, at both within-and transgenerational levels. In this study, we examined gamete quality in specimens exposed to future predicted (-0.4 units) pH conditions during gametogenesis. Egg physical characteristics, biochemical composition, and fatty acid profiles were assessed after two and six months of exposure, while sperm viability and velocity were analysed after six months of exposure. Considering the documented intraspecific variability in response to ocean acidification, this study involved two populations of Paracentrotus lividus. One population was sampled from the highly variable lagoon of Venice (Site 1), while the other was obtained from a coastal area (Site 2) characterized by more stable environmental conditions and facing minimal anthropogenic stress.A different response was highlighted in the two sites. Noteworthy trends emerged, especially in the fatty acid profile and sperm traits. Although adults were fed the same diet, Site 1 eggs contained more high-energetic fatty acids than Site 2, potentially boosting the survival odds for the next generation. Moreover, Site 1 sperms displayed higher viability but slower motility compared to those from Site 2. Within sites, a significant difference between time points and a change in the fitness strategy of sea urchin females emerged when comparing eggs spawned after two and six months of exposure to reduced pH. The effects of time and exposure pH are more pronounced in animals from Site 1, suggesting a higher adaptability of this population rather than negative effects of ocean acidification.Overall, our findings suggest that sea urchins have the potential to acclimate to reduced pH and to produce gametes of the same quality as controls held at the currently natural pH. Our findings emphasize the relevance of combining investigations of gamete quality characteristics, particularly egg biochemistry and fatty acid composition, and considering site variability to fully understand the transgenerational response potential of sea urchins to ocean acidification.

Aims The objective of this study was to investigate the effects of future warming and drought on (1) the biochemical composition of above-ground biomass of forage plants (Festuca arundinacea and Dactylis glomerata), (2) the potential mineralization of this material in soil, and (3) its priming effect on native soil organic matter. Methods We sampled above-ground plant material from spring regrowth and summer regrowth of a climate change experiment. While in spring, the plants were well watered, the summer regrowth was exposed to drought and elevated temperature (+3 °C) by infrared heating of the canopy during 3 weeks. We assessed the elemental and isotopie composition, lignin and non-cellulosic carbohydrate content and composition of plant material grown under all three conditions. Its mineralization potential in soil and priming effects were evaluated during laboratory incubation. Results Warming had no significant effect on elemental and stable isotope composition of both plant materials. In contrast, it resulted in reduction of lignin content for both plant species and decrease of the lignin-to-N ratio for F. arundinacea and increased non-cellulosic carbohydrate content for D. glomerata. Summer regrowth was characterised by increase of δ¹³C values, which is consistent with variations in stomatal conductance due to water shortage. Moreover, summer drought induced an increase in N content leading to decrease of the C/N ratio and increase of lignin-to-N ratio of summer regrowth compared to spring regrowth. Differences in decomposition were small, while priming effects were more strongly altered by the different exposure to enviromental. Conclusion Our results provide direct experimental evidence that extreme climatic events (high temperature and precipitation deficit) have an influence on soil carbon storage particularly through their effect on priming of native soil organic matter induced by altered plant litter. These effects seem to be governed by alterations of stoichiometry and to a smaller extent by alterations of plant chemical composition.

Microalgae biomass is considered one of the most promising raw materials for the development of high commercial value products, mainly because they are potential sources of proteins, lipids, carbohydrates, and vitamins. In this way, the optimization of culture medium of these microorganisms can help to reduce production costs, making final products more accessible. In this sense, the present study aimed to investigate the effect of different trace metal concentrations on growth and biochemical composition of Scenedesmus obliquus. Cultures of S. obliquus were performed using the LCA-AD medium (pH 7.6), in 2-L cylindrical borosilicate glass flasks that were constantly stirred by bubbling 0.7% CO2 enriched air (v/v), irradiance ranging from 520 to 1200 μmols m−2 s−1, and temperature at 22 ± 1 °C. Four trace metal concentrations were tested: control (standard concentration used on Bold’s Basal Medium), ten (10−1), hundred (10−2), and thousand (10−3) times less than control. The trace metal concentration did not significantly affect the growth of S. obliquus – all treatments have reached about 4.2 g L−1 on the tenth day of cultivation. As well for growth performance, no significant differences were observed among the treatments for biomass composition percentages. The dry S. obliquus biomass was mainly composed of carbohydrates (about 65%), crude protein (about 20%), and finally lipids (about 12%). These findings suggest that up to 1000-fold reduction in trace metal concentration does not affect the growth and biochemical composition of the green microalga S. obliquus.

Flax is one of the oldest oil crops, but only since the end of the twentieth century nutritional use of its whole seeds and flour has been resumed. This crop has been evaluated for its oil fatty acid composition, content of sterols and tocopherols, carbohydrate composition of mucilage, but a comprehensive study has never been carried out, so the aim of the work was to identify differences in the metabolomic profiles of flax lines contrasting in color and size of seeds. The biochemical composition of seeds from 16 lines of the sixth generation of inbreeding was tested using gas chromatography coupled with mass spectrometry. In total, more than 90 compounds related to sugars (78% of the identified substances), free fatty acids (13%), polyatomic alcohols (5%), heterocyclic compounds, free amino acids, phytosterols and organic acids (no more than 2.5% in total) were identified. Statistical analyses revealed six main factors. The first is a factor of sugar content; the second one affects most of organic acids, as well as some free fatty acids, not related to reserve ones, the third factor is related to compounds that play a certain role in the formation of “storage” substances and resistance to stress, the fourth factor is influencing free polar amino acids, some organic and free fatty acids, the fifth one is a factor of phenolic compounds, the sixth factor combined substances not included in the first five groups. Factor analysis made it possible to differentiate all 16 lines, 10 of which occupied a separate position by one or two factors. Interestingly, the first two factors with the highest loads (20 and 15% of the total variability, respectively) showed a separate position of the gc-432 line, which differed from the others, not only by chemical composition, but also by the phenotype of the seeds, while gc-159 differed from the rest ones by the complex of organic acids and other substances taking about 1% of the extracted substances of the seed. Thus, the analysis of metabolomic profiles is promising for a comprehensive assessment of the VIR flax genetic collection, which has wide biochemical diversity.