Pharmacological evaluation of the semi-purified fractions from the soft coral Eunicella singularis and isolation of pure compounds

Chemical Evaluation, Antioxidant, Antiproliferative, Anti-Inflammatory and Antibacterial Activities of Organic Extract and Semi-Purified Fractions of the Adriatic Sea Fan, Eunicella cavolini

Due to sedentary lifestyle and harsh environmental conditions, gorgonian coral extracts are recognized as a rich source of novel compounds with various biological activities, of interest to the pharmaceutical and cosmetic industries. The presented study aimed to perform chemical screening of organic extracts and semi-purified fractions obtained from the common Adriatic gorgonian, sea fan, Eunicella cavolini (Koch, 1887) and explore its abilities to exert different biological effects in vitro. Qualitative chemical evaluation revealed the presence of several classes of secondary metabolites extended with mass spectrometry analysis and tentative dereplication by using Global Natural Product Social Molecular Networking online platform (GNPS). Furthermore, fractions F4 and F3 showed the highest phenolic (3.28 ± 0.04 mg GAE/g sample) and carotene (23.11 ± 2.48 mg β-CA/g sample) content, respectively. The fraction F3 inhibited 50% of DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and ABTS (2,2′-azino-bis (3-ethylbenzthiazolin-6-yl) sulfonic acid) radicals at the concentrations of 767.09 ± 11.57 and 157.16 ± 10.83 µg/mL, respectively. The highest anti-inflammatory potential was exhibited by F2 (IC₅₀ = 198.70 ± 28.77 µg/mL) regarding the inhibition of albumin denaturation and F1 (IC₅₀ = 254.49 ± 49.17 µg/mL) in terms of soybean lipoxygenase inhibition. In addition, the most pronounced antiproliferative effects were observed for all samples (IC₅₀ ranging from 0.82 ± 0.14–231.18 ± 46.13 µg/mL) against several carcinoma cell lines, but also towards non-transformed human fibroblasts pointing to a generally cytotoxic effect. In addition, the antibacterial activity was tested by broth microdilution assay against three human pathogenic bacteria: Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The latter was the most affected by fractions F2 and F3. Finally, further purification, isolation and characterization of pure compounds from the most active fractions are under investigation.

Ergosterol Peroxide from the Medicinal Mushroom Ganoderma lucidum Inhibits Differentiation and Lipid Accumulation of 3T3-L1 Adipocytes

Ergosterol peroxide is a natural compound of the steroid family found in many fungi, and it possesses antioxidant, anti-inflammatory, anticancer and antiviral activities. The anti-obesity activity of several edible and medicinal mushrooms has been reported, but the effect of mushroom-derived ergosterol peroxide on obesity has not been studied. Therefore, we analyzed the effect of ergosterol peroxide on the inhibition of triglyceride synthesis at protein and mRNA levels and differentiation of 3T3-L1 adipocytes. Ergosterol peroxide inhibited lipid droplet synthesis of differentiated 3T3-L1 cells, expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAT/enhancer-binding protein alpha (C/EBPα), the major transcription factors of differentiation, and also the expression of sterol regulatory element-binding protein-1c (SREBP-1c), which promotes the activity of PPARγ, resulting in inhibition of differentiation. It further inhibited the expression of fatty acid synthase (FAS), fatty acid translocase (FAT), and acetyl-coenzyme A carboxylase (ACC), which are lipogenic factors. In addition, it inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) involved in cell proliferation and activation of early differentiation transcription factors in the mitotic clonal expansion (MCE) stage. As a result, ergosterol peroxide significantly inhibited the synthesis of triglycerides and differentiation of 3T3-L1 cells, and is, therefore, a possibile prophylactic and therapeutic agent for obesity and related metabolic diseases.

Secondary Metabolites from Gorgonian Corals of the Genus Eunicella: Structural Characterizations, Biological Activities, and Synthetic Approaches

Gorgonian corals, which belong to the genus Eunicella, are known as natural sources of diverse compounds with unique structural characteristics and interesting bioactivities both in vitro and in vivo. This review is focused primarily on the secondary metabolites isolated from various Eunicella species. The chemical structures of 64 compounds were divided into three main groups and comprehensively presented: a) terpenoids, b) sterols, and c) alkaloids and nucleosides. The observed biological activities of depicted metabolites with an impact on cytotoxic, anti-inflammatory, and antimicrobial activities were reviewed. The most promising biological activities of certain metabolites point to potential candidates for further development in pharmaceutical, cosmetic, and other industries, and are highlighted. Total synthesis or the synthetic approaches towards the desired skeletons or natural products are also summarized.

Insights into Ergosterol Peroxide's Trypanocidal Activity

Trypanosoma cruzi, which causes Chagas disease, is a significant health threat in many countries and affects millions of people. Given the magnitude of this disease, a broader understanding of trypanocidal mechanisms is needed to prevent and treat infection. Natural endoperoxides, such as ergosterol peroxide, have been shown to be toxic to parasites without causing harm to human cells or tissues. Although prior studies have demonstrated the trypanocidal activity of ergosterol peroxide, the cellular and molecular mechanisms remain unknown. The results of this study indicate that a free-radical reaction occurs in T. cruzi following ergosterol peroxide exposure, leading to cell death. Using a combination of biochemical, microscopic and in silico experimental approaches, we have identified, for the first time, the cellular and molecular cytotoxic mechanism of an ergosterol peroxide obtained from Pleurotus ostreatus (Jacq) P. Kumm. f. sp. Florida.

Soft coral Cespitularia stolonifera: New cytotoxic ceramides and gastroprotective activity

In the present study, a new ceramide, namely 2S, 3R-4E, 8E-2-(heptadecanoylamino)-heptadeca-4, 8-diene-1, 3-diol (1), along with four known steroids, including 24-methylcholesta-5, 24(28)-diene-3β-ol (2), 24-methylcholesta-5, 24(28)-diene-3β-acetate (3), 4-methyl-24-methylcholesta-22-ene-3-ol (4), and cholesterol, was isolated and characterized from CH₂Cl₂/MeOH extract of Cespitularia stolonifera. A new acetate derivative of compound 1, termed 2S, 3R-4E, 8E-2-(heptadecanoylamino)-heptadeca-4, 8-diene-1, 3-diacetate (1a), was also prepared in the present study. All the structures were established on the basis of modern spectroscopic techniques, including FT-IR, 1D, 2D-NMR, HRESI-MS, and GC-MS, in addition of chemical methods. (-)-Alloaromadendren, ledane, (1)-alloaromadendren oxide, isoaromadendrene epoxide and (-)-caryophellen oxide were identified from the n-hexane fraction using GC-MS. The extract and the two ceramides (1) and (1a) exhibited significant cytotoxic activity against lung cancer A549 cells, while the extract and the two steroids (2) and (3) exhibited significant cytotoxic activity against breast cancer MCF-7 cells. The CH₂Cl₂/MeOH extract exhibited significant antiulcer activity in both ethanol and acetic acid induced ulcer models in rats, as evidenced by histopathological, histochemical, and biochemical examinations.

HPTLC Fingerprints of Various Secondary Metabolites in the Traditional Medicinal Herb Hypochaeris radicata L

The aim of this work was to elucidate the various secondary metabolites such as alkaloids, flavonoids, glycosides, saponins, and terpenoids in the methanolic leaf and root extracts of Hypochaeris radicata, a most important traditional medicinal plant species in Nilgiris, the Western Ghats, India, using high performance thin layer chromatography (HPTLC). This study was carried out using CAMAG HPTLC system equipped with LINOMAT 5 applicator, TLC scanner 3, Reprostar 3, and winCATS 1.3.4 software. A comprehensive assortment of phytoconstituents in methanolic extracts through HPTLC fingerprinting profiles displayed the existence of alkaloids (3 in leaf and 1 in root extract), flavonoids (4 in leaf extract and 5 in root extract), glycosides (1 in leaf extract and 3 in root extract), saponins (1 in root extract), and terpenoids (1 in leaf and root extracts, resp.). The current study overlays boulevard for H. radicata to provide a direction for further exploration in precluding communicable and noncommunicable ailments.