scholarly journals Brief review of phototrophs in the Crimean hypersaline lakesand lagoons: diversity, ecological role, the possibility of using

2017 ◽  
Vol 2 (2) ◽  
pp. 80-85 ◽  
Author(s):  
N. V. Shadrin ◽  
E. V. Anufriieva ◽  
S. N. Shadrina
Keyword(s):  
Secondary Metabolites ◽  
Oxygenic Photosynthesis ◽  
Green Bacteria ◽  
Ecological Role ◽  
Anoxygenic Photosynthesis ◽  
Adaptive Mechanisms ◽  
Different Types ◽  
Extreme Habitats

Widespread, including in Crimea, hypersaline waters are among the most extreme habitats of the planet. The need to adapt organisms to living in polyextreme environment has led to the development of a variety of adaptive mechanisms with a synthesis of unique secondary metabolites, which makes organisms dwelling hypersaline waters very promising to use them in different areas of biotechnology and aquaculture. There are three groups of phototrophs using different types of phototrophy in the Crimean hypersaline waters: oxygenic photosynthesis (cyanobacteria, microalgae, and plants), anoxygenic photosynthesis (purple and green bacteria) and proton bacteriorhodopsin pump (archaea). Diversity and roles of these groups in the Crimean lakes and lagoons as well as some perspectives of their practical use are discussed.

scholarly journals ANTIMICROBIAL ACTIVITIES AND PHYTOCHEMICAL INVESTIGATION OF FERN, LYGODIUM FLEXUOSUM (LINN) SW.

2017 ◽  
Vol 4 (1) ◽  
pp. 87-91
Author(s):  
Jeeshna M.V
Keyword(s):  
Secondary Metabolites ◽  
Polar Solvent ◽  
Antimicrobial Activities ◽  
Klebsiella Pneumonia ◽  
Significant Activity ◽  
Active Constituent ◽  
Methanol Extracts ◽  
Phytochemical Investigation ◽  
Different Types ◽  
Rhizopus Sp

The present study revealed the presence of many medicinally active constituent in Lygodium flexuosum, suggesting that this species have potential to synthesize useful secondary metabolites. In this studies two different types (vegetative material and sporophyll bearing type) of this species showed the presence of secondary metabolites such as alkaloids, flavonoids, saponins, tannins, phenols and glycosides. In which vegetative material showed the presence of all secondary metabolites. The low polar solvent extracts such as petroleum ether and acetone showed minimum presence of secondary metabolites. The antibacterial studies revealed that methanol extracts of sporophyll type exhibited significant activity (8.5 mm) against the bacterium, Klebsiella pneumonia. The next antibacterial activity showed by chloroform extracts of sporophyll type against the same bacteria (8.2 mm). In antifungal studies, methanol extracts of vegetative material has the highest inhibitory activity (19.3 mm) against the fungus Cladosporium sp. Next higher fungal activity was showed by same extract of sporophyll type against the fungus Rhizopus sp. (16.08 mm). The study confirms the antimicrobial potential of Lygodium flexuosum extracted using various solvents.

scholarly journals Natural Products of Marine Macroalgae from South Eastern Australia, with Emphasis on the Port Phillip Bay and Heads Regions of Victoria

Marine Drugs ◽  
2020 ◽  
Vol 18 (3) ◽  
pp. 142 ◽  
Author(s):  
James Lever ◽  
Robert Brkljača ◽  
Gerald Kraft ◽  
Sylvia Urban
Keyword(s):  
Natural Products ◽  
Secondary Metabolites ◽  
Phenolic Acids ◽  
Red Algae ◽  
Brown Algae ◽  
Marine Macroalgae ◽  
Eastern Region ◽  
South Eastern ◽  
Eastern Australia ◽  
Different Types

Marine macroalgae occurring in the south eastern region of Victoria, Australia, consisting of Port Phillip Bay and the heads entering the bay, is the focus of this review. This area is home to approximately 200 different species of macroalgae, representing the three major phyla of the green algae (Chlorophyta), brown algae (Ochrophyta) and the red algae (Rhodophyta), respectively. Over almost 50 years, the species of macroalgae associated and occurring within this area have resulted in the identification of a number of different types of secondary metabolites including terpenoids, sterols/steroids, phenolic acids, phenols, lipids/polyenes, pheromones, xanthophylls and phloroglucinols. Many of these compounds have subsequently displayed a variety of bioactivities. A systematic description of the compound classes and their associated bioactivities from marine macroalgae found within this region is presented.

scholarly journals New Ecological Role of Seaweed Secondary Metabolites as Autotoxic and Allelopathic

2020 ◽  
Vol 11 ◽  
Author(s):  
Daniela Bueno Sudatti ◽  
Heitor Monteiro Duarte ◽  
Angélica Ribeiro Soares ◽  
Leonardo Tavares Salgado ◽  
Renato Crespo Pereira
Keyword(s):  
Secondary Metabolites ◽  
Ecological Role

scholarly journals Evolutionary ecology during the rise of dioxygen in the Earth's atmosphere

2008 ◽  
Vol 363 (1504) ◽  
pp. 2651-2664 ◽  
Author(s):  
Norman H Sleep ◽  
Dennis K Bird
Keyword(s):  
Ferrous Iron ◽  
Evolutionary Ecology ◽  
Granitic Rocks ◽  
Oxygenic Photosynthesis ◽  
Ridge Axis ◽  
Anoxygenic Photosynthesis ◽  
Arc Volcanism ◽  
Oxidized Iron ◽  
Mid Ocean Ridge ◽  
Ocean Ridge

Pre-photosynthetic niches were meagre with a productivity of much less than 10 −4 of modern photosynthesis. Serpentinization, arc volcanism and ridge-axis volcanism reliably provided H 2 . Methanogens and acetogens reacted CO 2 with H 2 to obtain energy and make organic matter. These skills pre-adapted a bacterium for anoxygenic photosynthesis, probably starting with H 2 in lieu of an oxygen ‘acceptor’. Use of ferrous iron and sulphide followed as abundant oxygen acceptors, allowing productivity to approach modern levels. The ‘photobacterium’ proliferated rooting much of the bacterial tree. Land photosynthetic microbes faced a dearth of oxygen acceptors and nutrients. A consortium of photosynthetic and soil bacteria aided weathering and access to ferrous iron. Biologically enhanced weathering led to the formation of shales and, ultimately, to granitic rocks. Already oxidized iron-poor sedimentary rocks and low-iron granites provided scant oxygen acceptors, as did freshwater in their drainages. Cyanobacteria evolved dioxygen production that relieved them of these vicissitudes. They did not immediately dominate the planet. Eventually, anoxygenic and oxygenic photosynthesis oxidized much of the Earth's crust and supplied sulphate to the ocean. Anoxygenic photosynthesis remained important until there was enough O 2 in downwelling seawater to quantitatively oxidize massive sulphides at mid-ocean ridge axes.

scholarly journals Type II photosynthetic reaction center genes of avocado (Persea americana Mill.) bark microbial communities are dominated by aerobic anoxygenic Alphaproteobacteria

2020 ◽  
Author(s):  
Eneas Aguirre-von-Wobeser
Keyword(s):  
Microbial Communities ◽  
Reaction Center ◽  
Photosynthetic Reaction Center ◽  
Persea Americana ◽  
Algorithm Analysis ◽  
Tree Bark ◽  
Oxygenic Photosynthesis ◽  
Type Ii ◽  
Additional Energy ◽  
Anoxygenic Photosynthesis

AbstractThe tree bark environment is an important microbial habitat distributed worldwide on thrillions of trees. However, the microbial communities of tree bark are largely unknown, with most studies on plant aerial surfaces focused on the leaves. Recently, we presented a metagenomic study of bark microbial communities from avocado. In these communities, oxygenic and anoxygenic photosynthesis genes were very abundant, especially when compared to rhizospheric soil from the same trees. In this work, Evolutionary Placement Algorithm analysis was performed on metagenomic reads orthologous to the PufLM gene cluster, encoding for the bacterial type II photosynthetic reaction center. These photosynthetic genes were found affiliated to different groups of bacteria, mostly aerobic anoxygenic photosynthetic Alphaproteobacteria, including Sphingomonas, Methylobacterium and several Rhodospirillales. These results suggest that anoxygenic photosynthesis in avocado bark microbial communities functions primarily as additional energy source for heterotrophic growth. Together with our previous results, showing a large abundance of cyanobacteria in these communities, a picture emerges of the tree holobiont, where light penetrating the trees canopies and reaching the inner stems, including the trunk, is probably utilized by cyanobacteria for oxygenic photosynthesis, and the far-red light aids the growth of aerobic anoxygenic photosynthetic bacteria.

scholarly journals Antioxidant Activity, Total Phenols, Flavonoids and LCMS Profile of Chamaecrista hildebrandtii (Vatke) Lock and Clerodendrum rotundifolium (Oliv.)

2019 ◽  
pp. 1-11
Author(s):  
Rechab S. Odhiambo ◽  
Patrick G. Kareru ◽  
Erastus K. Mwangi ◽  
Daniel W. Onyango
Keyword(s):  
Antioxidant Activity ◽  
Secondary Metabolites ◽  
Tannic Acid ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Total Phenols ◽  
Flavonoid Content ◽  
Methanolic Extracts ◽  
Significant Difference ◽  
Different Types

Aims: The purpose of the study was to determine the antioxidant activity, quantify total phenols and total flavonoids and characterize the secondary metabolites present in methanolic extracts of Chamaecrista hildebrandtii and Clerodendrum rotundifolium using liquid chromatography coupled to mass spectrometry (LC-MS). Methodology: The total phenol and flavonoid contents were determined spectrophotometrically while the antioxidant activity was evaluated using the 2, 2-Diphenyl-1-Picrylhydrazyl (DPPH) free radical scavenging method. The secondary metabolites present in the methanolic leaves extracts were evaluated using LC-MS. Results: The extracts of C. hildebrandtii showed a significantly higher antioxidant activity (IC50 = 8.7 mg/mL) compared to C. rotundifolium (IC50= 28.5 mg/mL). Both methanolic extracts of C. hildebrandtii and C. rotundifolium had common and different types of flavonoids such as quercetin, rutin, (+)-catechin 3-O-gallate and luteolin 6-C-glucoside among others that could be responsible for the observed antioxidant activity. The total phenolic content of C. hildebrandtii (1.33±0.07 mg/g tannic acid equivalents) was significantly higher than that of C. rotundifolium (0.25±0.00 mg/g tannic acid equivalents). However, there was no statistically significant difference (p>0.05) in total flavonoid content of C. hildebrandtii (2.69±0.33 mg/g catechin equivalents) and C. rotundifolium (2.36±0.16 mg/g catechin equivalents). Conclusion: The results of the present study suggested that the good antioxidant activity exhibited by C. hildebrandtii may probably have been brought about by various secondary metabolites functioning in synergy.

scholarly journals Photosynthetic performance in cyanobacteria with increased sulphide tolerance: an analysis comparing wild-type and experimentally derived strains

2021 ◽  
Author(s):  
Elena Martín-Clemente ◽  
Ignacio J. Melero-Jiménez ◽  
Elena Bañares-España ◽  
Antonio Flores-Moya ◽  
María J. García-Sánchez
Keyword(s):  
Resistance Mechanisms ◽  
Photosynthetic Performance ◽  
Oxygenic Photosynthesis ◽  
Wild Type ◽  
Sensitive Species ◽  
Anoxygenic Photosynthesis ◽  
In The Wild ◽  
Photosynthetic Machinery ◽  
Type Strains ◽  
Shed Light

AbstractSulphide is proposed to have influenced the evolution of primary stages of oxygenic photosynthesis in cyanobacteria. However, sulphide is toxic to most of the species of this phylum, except for some sulphide-tolerant species showing various sulphide-resistance mechanisms. In a previous study, we found that this tolerance can be induced by environmental sulphidic conditions, in which two experimentally derived strains with an enhanced tolerance to sulphide were obtained from Microcystis aeruginosa, a sensitive species, and Oscillatoria, a sulphide-tolerant genus. We have now analysed the photosynthetic performance of the wild-type and derived strains in the presence of sulphide to shed light on the characteristics underlying the increased tolerance. We checked whether the sulphide tolerance was a result of higher PSII sulphide resistance and/or the induction of sulphide-dependent anoxygenic photosynthesis. We observed that growth, maximum quantum yield, maximum electron transport rate and photosynthetic efficiency in the presence of sulphide were less affected in the derived strains compared to their wild-type counterparts. Nevertheless, in 14C photoincoporation assays, neither Oscillatoria nor M. aeruginosa exhibited anoxygenic photosynthesis using sulphide as an electron donor. On the other hand, the content of photosynthetic pigments in the derived strains was different to that observed in the wild-type strains. Thus, an enhanced PSII sulphide resistance appears to be behind the increased sulphide tolerance displayed by the experimentally derived strains, as observed in most natural sulphide-tolerant cyanobacterial strains. However, other changes in the photosynthetic machinery cannot be excluded.

scholarly journals THERAPEUTIC POTENTIAL OF PLANT-DERIVED OLIGOSTILBENES AND STILBENE GLYCOSIDES

2020 ◽  
pp. 13-19
Author(s):  
SUTAPA BISWAS MAJEE ◽  
DIPANJANA ASH ◽  
DHRUTI AVLANI ◽  
GOPA ROY BISWAS
Keyword(s):  
Secondary Metabolites ◽  
Animal Studies ◽  
Therapeutic Potential ◽  
Microbial Infection ◽  
Pathological Conditions ◽  
Different Types ◽  
First Pass Metabolism ◽  
First Pass ◽  
Health Promoting ◽  
Pass Metabolism

Stilbenoids constitute a major class of plant-derived secondary metabolites occurring in abundance across several families and are well-known for their nutritional and health-promoting benefits. Several investigations have established their therapeutic potential in the management of different types of cancer, neuroinflammation, arthritis, disorders in lipid metabolism, microbial infection etc. Studies on resveratrol monomer, oxyresveratrol, their synthetic analogs, piceatannol, pterostilbene can be found in the literature. But a collective and comprehensive review on chemistry, pharmacological effects, structure-activity relationship and pharmacokinetics of plant-derived oligostilbenes and stilbene glycosides is missing. These phytochemicals are generally characterised by poor oral bioavailability due to extensive first-pass metabolism and conjugation. The present chapter aims to fill up these lacunae and also focuses on further studies that can be performed in the future to translate these immensely potential secondary metabolites into human clinical setting from cell culture and animal studies at the preclinical level for effective therapeutic intervention of various pathological conditions.

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