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Plants known as obligate aerobes developed different mechanisms to overcome the damage incurred under oxygen limitation. One of the survival strategies to have commonly appeared in hydrophytic plants is the escape strategy, which accelerates plant axial organs' growth in order to escape hypoxic conditions as soon as possible. The present study aimed to distinguish the alterations in coleoptile elongation, viability and metabolic profiles in coleoptiles of slow- and fast-growing rice varieties. All the parameters were tested at 3, 5 and 7 days after sowing, to highlight changes during seedling development in normal and submerged conditions. The obtained results indicated that coleoptile elongation correlated with higher resistance to oxygen deprivation. GS-MS-based metabolic profiling indicated that coleoptiles of the fast-growing cultivar accumulated higher amounts of sugar phosphates, disaccharides, fatty acid derivatives and sterols, which are important for maintaining growth, membrane stability and viability. The slow-growing variety was characterized by a greater abundance of carboxylates, including lactate and phosphoric acid, indicating an energy crisis and cytosol acidification, leading to cell damage and low tolerance. Therefore, a metabolomics approach could be used for phenotyping (chemotyping) in the large-scale screening of newly developed varieties with higher tolerance to oxygen deprivation. [ABSTRACT FROM AUTHOR]

Tobacco BY-2 cell culture is one of the most widely used models in plant biology. The main advantage of BY-2 suspension cultures is the synchronization of cell development and the appearance of polar elongation. In batch culture, BY-2 cells passed through the lag, proliferation, elongation, and stationary phases. During this process, the composition of the growth medium changed dramatically. Sucrose was rapidly eliminated; hexose first accumulated and then depleted. The medium's pH initially decreased and then rose with aging. As a result of the crosstalk between the internal and external stimuli, cells pass through complicated systemic rearrangements, which cause metabolomic alterations. The early stages were characterized by high levels of amino acids and sterols, which could be interpreted as the result of synthetic activity. The most intense rearrangements occurred between the proliferation and active elongation stages, including repression of amino acid accumulation and up-regulation of sugar metabolism. Later stages were distinguished by higher levels of secondary metabolites, which may be a non-specific response to deteriorating conditions. Senescence was followed by some increase in fatty acids and sterols as well as amino acids, and probably led to self-destructive processes. A correlation analysis revealed relationships between metabolites' covariation, their biochemical ratio, and the growth phase. [ABSTRACT FROM AUTHOR]

The work is devoted to the mycelium biochemical composition of Stagonospora cirsii C-211, Calophoma complanata 32.121, Didymella macrostoma 32.52. These phylogenetically distant species of phoma-like micromycetes are the potential mycoherbicides of Cirsium arvense, Heracleum sosnowskyi, and Convolvulus arvensis, respectively. The S. cirsii C-211, C. complanata 32.121, D. macrostoma 32.52 mycelium in the early stationary growth phase was obtained on sucrose-soybean nutrient medium. It was shown that the lipid and carbohydrate (polyols, sugars) profiles of these strains have much in common. We suppose that levels of arabitol and trehalose influence to the stress-resistant of phoma-like micromycetes. In particularly, these carbohydrates serve structural and protective roles in the cell walls during osmotic and temperatures stress. The ratio of phosphatidylcholine to phosphatidylethanolamine and the proportion of phosphatidylserine among structural lipids also determine the properties of mycelium, and can be used to assess its quality.

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Marine invertebrates are a promising source of novel natural products with biological activities. The phylum Bryozoa is relatively under-investigated in this context, although a number of compounds with medical potential has been discovered in recent years. Here, we report on the novel group of brominated metabolites from the bryozoan Terminoflustra membranaceatruncata, including analysis of biological activities of the tribrominated terminoflustrindole A (Cm-1) and the structures of the related dibrominated variants terminoflustrindoles B and C. Terminoflustrindole A was previously shown to have fungicidal properties. Although they vary by just one bromine group in each case from terminoflustrindole A, in this study, we report that terminoflustrindoles B and C exhibit no antimicrobial activity in the same assays. In addition to displaying antifungal activity, Terminoflustrindole A was also found to exhibit potent cytotoxic activity when tested against tumour cell lines. The gradient distribution of this compound within the bryozoan colony was demonstrated using LC-MS-analysis. [ABSTRACT FROM AUTHOR]

The morphology, histochemistry and ultrastructure of the glandular trichomes on Empetrum nigrum leaves have been studied and more than a third of the metabolites were identified. Samples of the leaves were fixed and processed for light and electron microscopy. Glandular trichomes are situated on the inner surface of the rolled leaves. They have a clavate head and a short stalk. Histochemical tests and fluorescent microscopy demonstrate differentiated staining of the various cell types in the glandular trichome for proteins, pectins, lipids, tannins and phenylpropanoids. During secretion, the secretory cells contain rough and smooth endoplasmic reticulum, Golgi stacks with large vesicles, diversiform leucoplasts in contact with a reticular sheath and opaque deposits in the vacuoles. There are ultrastructural and functional differences between the secretory cells in the trichome head: synthesis of hydrophilic substances predominately occurs in the upper and middle secretory cells, whereas synthesis of lipophilic compounds takes place in the middle and lower secretory cells. Gas chromatography-mass spectrometry was used to determine the content of metabolites in the methanol extracts from the leaves. Many phenolic compounds (phenolic acids, bibenzyls, catechins, flavanones and flavan-3-ols) as well as several terpenoids were found. Two chalcones (2′,4′-dimethoxydihydrochalcone and 2′,4′,6′-trihydroxydihydrochalcone), one bibenzyl (batatasin III), one flavanone (7-hydroxyflavanone) and 8 terpenoids (including phytol, α-tocopherol, ß-sitosterol, α-amyrin, uvaol, oleanolic acid, ursolic acid and dehydroursolic acid) were identified in E. nigrum leaf extracts. The total yield of phenolic compounds is five to six times higher than the yield of terpenoids. It has been established that chalcones have no hydroxyl groups in ring B whereas bibenzyls have a hydroxyl group in the 3-position in ring B. On the basis of the histochemistry, fluorescent microscopy, ultrastructure and chemical analysis, it may be concluded that synthesis and accumulation of phenolic substances and terpenoids takes place in the clavate glandular trichomes. Secondary metabolites synthesized in the trichomes protect leaf tissues from viruses, bacteria and pathogenic fungi. [ABSTRACT FROM AUTHOR]

B Journal: b Natural Product Research B Bibliometrics: b Volume 31, Number 16, pages 1840-1848 B DOI: b https://doi.org/10.1080/14786419.2016.1261344 When the article was first published online, the below reference was not included and cited in the article. Yao B, Prinsep MR, Nicholson BK and Gordon DP, The Pterocellins, Novel Bioactive Alkaloids from the Marine Bryozoan Pterocella vesiculosa, J. Nat. [Extracted from the article]