Pyrenosetins A–C, New Decalinoylspirotetramic Acid Derivatives Isolated by Bioactivity-Based Molecular Networking from the Seaweed-Derived Fungus Pyrenochaetopsis sp. FVE-001

Marine algae represent a prolific source of filamentous fungi for bioprospecting. In continuation of our search for new anticancer leads from fungi derived from the brown alga Fucus vesiculosus, an endophytic Pyrenochaetopsis sp. FVE-001 was selected for an in-depth chemical analysis. The crude fungal extract inhibited several cancer cell lines in vitro, and the highest anticancer activity was tracked to its CHCl3–soluble portion. A bioactivity-based molecular networking approach was applied to C18-SPE fractions of the CHCl3 subextract to predict the bioactivity scores of metabolites in the fractions and to aid targeted purification of anticancer metabolites. This approach led to a rapid isolation of three new decalinoylspirotetramic acid derivatives, pyrenosetins A–C (1–3) and the known decalin tetramic acid phomasetin (4). The structures of the compounds were elucidated by extensive NMR, HR-ESIMS, FT-IR spectroscopy, [α]D and Mosher’s ester method. Compounds 1 and 2 showed high anticancer activity against malignant melanoma cell line A-375 (IC50 values 2.8 and 6.3 μM, respectively), in line with the bioactivity predictions. This is the first study focusing on secondary metabolites of a marine-derived Pyrenochaetopsis sp. and the second investigation performed on the member of the genus Pyrenochaetopsis

Pyrenosetin D, a New Pentacyclic Decalinoyltetramic Acid Derivative from the Algicolous Fungus Pyrenochaetopsis sp. FVE-087

The fungal genus Pyrenochaetopsis is commonly found in soil, terrestrial, and marine environments, however, has received little attention as a source of bioactive secondary metabolites so far. In a recent work, we reported the isolation and characterization of three new anticancer decalinoyltetramic acid derivatives, pyrenosetins A-C, from the Baltic Fucus vesiculosus-derived endophytic fungus Pyrenochaetopsis sp. FVE-001. Herein we report a new pentacyclic decalinoylspirotetramic acid derivative, pyrenosetin D (1), along with two known decalin derivatives wakodecalines A (2) and B (3) from another endophytic strain Pyrenochaetopsis FVE-087 isolated from the same seaweed and showed anticancer activity in initial screenings. The chemical structures of the purified compounds were elucidated by comprehensive analysis of HR-ESIMS, FT-IR, [a]D, 1D and 2D NMR data coupled with DFT calculations of NMR parameters and optical rotation. Compounds 1-3 were evaluated for their anticancer and toxic potentials against the human malignant melanoma cell line (A-375) and the non-cancerous keratinocyte cell line (HaCaT). Pyrenosetin D (1) showed toxicity towards both A-375 and HaCaT cells with IC50 values of 77.5 and 39.3 μM, respectively, while 2 and 3 were inactive. This is the third chemical study performed on the fungal genus Pyrenochaetopsis and the first report of a pentacyclic decalin ring system from the fungal genus Pyrenochaetopsis

Biologically active compounds form seafood processing by-products

Every year a considerable amount of seafood is discarded as processing leftovers and current estimates revealed that the discard exceed over 20 million tons equivalent to 25 % of the total production. Common seafood processing by-products, including fish oil, fishmeal, fertilizer, pet food and fish silage, generate low income compared to that of effort employed to recycle the waste. Recent advanced biotechnology and biochemistry research has identified number of biologically active compounds form seafood processing by-products while giving a new insight to the classical by-product industry. Exploration of seafood processing leftover for bioactive compounds brings high value for the processing by-products. In this chapter focus was given for comprehensive understanding of seafood processing by-products, exploration of bioactive compounds and biological activities of by-product-derived compounds

Active ingredients from marine microorganisms for modern nutraceuticals

Natural products have been used as a prominent source to prevent and cure various kinds of diseases for centuries. Earlier, diet was composed of these biologically active natural products with the aim of earning additional health benefits rather than basic nutritional requirements. The improvement of applications of these biologically active natural metabolites in food products leads to the term “nutraceutical” by merging two main sectors, “nutrition” and “pharmaceutical,” which have direct effect on human health. Nutraceuticals became popular among health-conscious community and therefore, global nutraceutical market is growing day by day. The classical definition of nutraceutical is “a food or part of a food that provides medical or health benefits, including the prevention and/or treatment of a disease” is no longer applicable for modern nutraceuticals. In response to growing consumer interest on products that have potential to improve wellness and to combat with novel diseases, a number of nonfood-derived ingredients that are recognized as safe are used in nutraceuticals. Changes in modern life style and eating patterns have created

Marine algae for protecting your brain: neuroprotective potentials of marine algae

The health of the brain plays a critical role in day-today activity as equally as the health of the rest of the body, and hence maintaining brain health is vital as you age. In fact, many neurological disorders are hard to reverse after they arise, and the best available option for such complications is prevention. Therefore, there has been an increasing interest in the substances that can improve brain health and protect brain from adverse elements. For quite long, many natural sources have been screened for potential neuroprotective ingredients. Among the potential sources that have brain protective metabolites, marine algae have received considerable attention. In this chapter, we aim to compile available literature and reveal the neuroprotective potential of marine algae-derived materials

EGFR tyrosine kinase inhibitory peptide attenuates Helicobacter pylori-mediated hyper proliferation in AGS enteric epithelial cells

Helicobacter pylori infection is one of the most critical causes of stomach cancer. The current study was conducted to explore the protective effects of an isolated active peptide H-P-6 (Pro-Gln-Pro-Lys-Val-Leu-Asp-Ser) from microbial hydrolysates of Chlamydomonas sp. against H. pylori-induced carcinogenesis. The peptide H-P-6 has effectively suppressed H. pylori-induced hyper-proliferation and migration of gastric epithelial cells (AGS). However, the peptide did not inhibit the viability of the bacteria or invasion into AGS cells. Therefore, the effect of the peptide on regulating H. pylori-induced molecular signaling was investigated. The results indicated that H. pylori activates the EGFR tyrosine kinase signaling and nuclear translocation of the β-catenin. The EGFR activation has led to the up-regulation of PI3K/Akt signaling pathway. Moreover, the nuclear translocation levels of β-catenin were significantly increased as a result of Akt mediated down-regulation of GSK3/β protein levels in the cytoplasm. Both of these consequences have resulted in increased expression of cell survival and migration related genes such as c-Myc, cyclin-D, MMP-2 and matrilysin. Interestingly, the isolated peptide potently inhibited H. pylori-mediated EGFR activation and thereby down-regulated the subsequent P13K/Akt signaling leading to β-catenin nuclear translocation. The effect of the peptide was confirmed with the use of EGFR tyrosine kinase inhibitor AG1487 and molecular docking studies. Collectively this study identifies a potent peptide which regulates the H. pylori-induced hyper-proliferation and migration of AGS cells at molecular level

Marine sponge-associated microbes: a source of biologically active metabolites

Since the first exploration of the marine environment for natural compounds in 1945 by Werner Bergmann, marine sponges have been considered the most prolific and important source of new bioactive compounds in the marine environment. Because of their immense production of new compounds, sponges are considered a chemical factory in the marine environment and a gold mine to chemists. Thus, marine sponges have gained much attention in various scientific disciplines (Bergmann and Feeney 1951; Baby and Sujatha 2010). The pioneering work of Werner Bergmann has led to the development of chemical derivatives Ara-A (vidarabine) and Ara-C (cytarabine), two nucleosides with significant anticancer and antiviral activity that have been approved for clinical use as the first marine-derived natural products. Since then, marine sponges have been a good candidate for pharmaceutically active metabolites and thousands of research articles have been published to reveal their potential (Molinski et al. 2009; Mayer et al. 2010)

Tyrosol exerts a protective effect against dopaminergic cell death in in vitro model of Parkinson's disease

Experimental evidence suggests that tyrosol [2-(4-hydroxyphenyl)ethanol] exhibits potent protective activities against several pathogeneses. In this study, we evaluated the protective effect of tyrosol against 1-methyl-4-phenylpyridinium (MPP)-induced CATH.a neuron cell death. Tyrosol dose-dependently protected CATH.a cells from MPP-induced cell death and the protection was more apparent after prolong incubation (48 h). The data showed that tyrosol treatment suppressed the reduction of phospho-tyrosine hydroxylase level in CATH.a cells. Further, the compound repressed MPP-induced depletion of mitochondrial membrane potential (Δψ) and thereby maintained intracellular ATP production in the cell. The cellular signalling pathway studies revealed that tyrosol protected CATH.a cells from MPP-induced apoptotic signalling, most likely via activation of PI3K/Akt signalling pathway along with up-regulation of anti-oxidative enzymes (SOD-1 and SOD-2) and DJ-1 protein in the cell. Collectively, present study demonstrates that tyrosol significantly protects dopaminergic neurons from MPP-induced degradation, and reveals potential neuroprotective mechanism of tyrosol