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Acanthophora spicifera harbors a diverse array of secondary metabolites with therapeutic potential. The aim of this study is to isolate and characterize secondary metabolites from A. spicifera and then evaluate the antiproliferation, antibacterial, and biofilm prevention properties, followed by an analysis of molecular docking experiments. By employing chromatographic analysis and NMR spectroscopy, the isolated compounds were, the known flavonol, 8-hydroxyquercetagetin (1), three recognized steroids cholest-4-ene-3,6-dione (2), cholest-5-en-3β-ol (3), and 5α-cholestane-3,6-dione (4), and 2-bromohexadecanoic acid (5). These compounds exhibited antimicrobial effects against various Gram-negative and Gram-positive bacteria with inhibition zones ranging from 6.5 ± 0.2 to 17.2 ± 0.12 mm and 7.0 ± 0.4 to 15.3 ± 0.60 mm, respectively. Compounds 1 and 2 inhibited biofilm formation in P. aeruginosa and S. aureus. Compounds 1–4 demonstrated binding affinity values between −7.5 and −9.4 kcal/mol to protein 1A0G. These binding affinity values were akin to that of amoxicillin, implying that one potential antibacterial mechanism of action of these compounds may involve the inhibition of bacterial cell wall synthesis. All compounds showed no toxicity against Artemia salina and weak activity against Lymphoma and Lewis lung carcinoma cell lines with LD50 > 100 μg/mL.

Objective: Inflammation is the initial physiological reaction of the immune system to infection or irritation, leading significant risk factors for several forms of cancer. The genus Asteriscus has been observed to possess a notable abundance of sesquiterpenes with anti-inflammatory properties. This study was designed to assess the anti-inflammatory activity of the sesquiterpenoids isolated from Asteriscus graveolens. Methods: The organic extract of the Asteraceae plant A. graveolens was subjected to different chromatographic and spectroscopic techniques for isolation, purification, and identification of sesquiterpenoid contents. The isolated compounds were screened for antiinflammatory activities in two animal models: rat paw edema and rat ear edema. Histopathological examinations as well as biochemical markers of inflammation were assessed. This was followed by in silico screening for anti-inflammatory activity. Results: Four known sesquiterpenoids were isolated from A. graveolens, including two humulene derivatives, namely, 9-oxohumula-4-en-6,15-olide (1), and 9-oxohumula-1(10)(Z),4,7(E)-trien-6,15-olide (2) and two bisabolene derivatives, identified as bisabola-2,10-dien-1-one (3) and 6-hydroxybisabola-2,10-dien-1-one (4) described. In the rat paw edema model, compound 2 showed highest activity in preventing formation carrageenan-induced paw edema. This was confirmed by histopathological examinations that indicated partial preservation of the epidermal and dermal layers. Further, the compound significantly inhibited cyclooxygenase-2 (COX-2) and tumor necrosis factor-a (TNF-a) release. In the croton oil indued rat ear edema, compounds 2 and 4 significantly inhibited ear edema and protected against histopathological alterations. This was associated with prevention of myeloperoxidase (MPO) concentration in ear tissues. Molecular docking and molecular dynamic simulation indicated the affinity and docking stability of compounds 1-4 to the selected inflammatory protein. Conclusion: Phytochemical investigation of A. graveolens resulted in the isolation and characterization of four sesquiterpenes. In particular, compound 2 showed potent anti-inflammatory activity in carrageenan rat paw edema and croton oil ear edema. [ABSTRACT FROM AUTHOR]

Purification of the organic extract of Laurencia obtusa Lamouroux by column chromatography and preparative thin layer chromatography provided four new compounds: a eudesmane-type sesquiterpenoid [eudesma-4(15),11-diene-5,7-diol (1)], a cuparane-type sesquiterpenoid [10-hydroxycuparaldehyde (2)], and two nor-cuparanes [3-hydroxy-15-nor-cuparan-10β-ol (3) and 2-bromo-3-hydroxy-15-nor-cuparan-10β-ol (4)]. Structural identification was made possible by comparison of spectral data with those reported in the literature. Compounds 3 and 4 are significant as nor-cuparanes are rarely isolated from marine environment. 1 showed moderate anticandidal activity, whereas 2 exhibited reasonable antibacterial activity against multidrug-resistant bacteria (especially Gram-positive). All the compounds are nontoxic to Artemia salina.

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Titanium dioxide (TiO2) nanoparticles were synthesized via a novel eco-friendly green chemistry approach using marine natural extracts of two red algae (Bostrychia tenella and Laurencia obtusa), a green alga (Halimeda tuna), and a brown alga (Sargassum filipendula) along with a marine sponge sample identified as Carteriospongia foliascens. X-ray diffraction (XRD), scanning electron microscope (SEM), UV–Vis, X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy (FTIR) were employed to characterize the crystal structure, surface morphology, and optical properties of the synthesized nanoparticles. Each of the as-synthesized marine extract based TiO2 nanoparticles was individually incorporated as an antifouling agent to form a newly fabricated marine paint formulation. The newly prepared formulations were applied on unprimed steel panels. A comparative study with a commercial antifouling paint (Sipes Transocean Coatings Optima) was carried out. After 108 days of the coated steel panels' immersion in the Eastern Harbour seawater of Alexandria-Egypt, the prepared paints using B. tenella and C. foliascens extracts demonstrated an excellent antifouling performance toward fouling organisms by inhibiting their settlement and controlling their adhesion onto the immersed panels. In contrast, heavy fouling with barnacles was observed on the surface of the coated panel with the commercial paint. The physicochemical parameters of the seawater surrounding the immersed coated panels were estimated to investigate the influence of the fabricated paint formulations. Interestingly, no effects of the immersed coated panels on the physicochemical characteristics of the surrounding seawater were observed. Based on the obtained results and a comparison with commercially available antifouling products, the marine extract based TiO2 nanoparticle preparations of B. tenella and C. foliascens are promising candidates for eco-friendly antifouling agents. Based on the obtained results and a comparison with commercially available antifouling products, the marine extract based TiO2 nanoparticle preparations of B. tenella and C. foliascens are promising candidates for eco-friendly antifouling agents, which could be attributed to the small crystallite sizes of 22.86 and 8.3 nm, respectively, in addition to the incorporation of carbon in the crystal structure of the nanoparticles. [ABSTRACT FROM AUTHOR]

Chemical investigation on the ethyl acetate extract of the aerial parts of Begonia sp. afforded a new steroid glycoside, 9(11)α,16(17)α-dioxirane-20,25-dihydroxy-β-sitosterol-3-O-β-glucopyranoside (1) along with a known steroidal glycoside, β-sitosterol-3-O-β-D-glucopyranoside (2). The Chemical structures were elucidated by 1D and 2D NMR and mass spectroscopic analysis. Cytotoxicity against four different cancer cell lines (HeLa, T47D, WiDr and Vero) was assessed. Compound 1 was more potent and selective against breast cancer cell line (T47D) than other cell lines with an IC50 value of 0.16 µg/mL. Further docking study of 1 exhibited the preference of molecule to bind in the epidermal growth factor receptor tyrosine kinase (EGFR-TK) binding pockets with docking scores of −97.8800 (PLANTS) and −3.56 kcal/mol (AutoDock 4.2.6). [ABSTRACT FROM AUTHOR]

Background and Objective: With regard to the uniqueness of the red algae of the genus Laurencia as the source of C15-acetogenins, along with the diversity of biological applications; the acetogenin content of the Red Sea Laurencia obtusa was investigated. Materials and Methods: Fractionation and purification of the CH2Cl2/MeOH extract were carried out by applying several chromatographic techniques, including column and preparative thin-layer chromatography; followed by a series of 1H nuclear magnetic resonance measurements to give rise of some interesting notes. Toxicity to Artemia salina was evaluated. The apoptosis induced by these two compounds was demonstrated by DNA fragmentation assay and microscopic observation. Results: A new rare chloroallene-based C15 acetogenin, laurentusenin (1) along with a new furan ring containing C15 acetogenin, laurenfuresenin (2), were isolated from the red alga L. obtusa. Comparing 1D and 2D NMR, MS, ultraviolet and infrared radiation spectral data for the newly isolated compounds with the reported bromoallene containing acetogenins spectral data was played the crucial role for characterization of their chemical structures. 1 and 2 exhibited bare toxicity (LD50 >12 mM) in test organism, A. salina and induced apoptotic death confirmed by DNA fragmentation and microscopic investigations. Conclusion: The isolated metabolite 1 showed unusual substituted allene side chain, while 2 inserted furan ring as a new acetogenin nucleus. Both compounds may play a role in apoptosis induction and initiation and propagation of inflammatory responses. [ABSTRACT FROM AUTHOR]