Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Peperomia obtusifolia (L.) A. Dietr., native to Middle America, is an ornamental plant also traditionally used for its mild antimicrobial properties. Chemical investigation on the leaves of P. obtusifolia resulted in the isolation of two previously undescribed compounds, named peperomic ester (1) and peperoside (2), together with five known compounds, viz. N-[2-(3,4-dihydroxyphenyl)ethyl]-3,4-dihydroxybenzamide (3), becatamide (4), peperobtusin A (5), peperomin B (6), and arabinothalictoside (7). The structures of these compounds were elucidated by 1D and 2D NMR techniques and HREIMS analyses. Compounds 1–7 were evaluated for their anthelmintic (against Caenorhabditis elegans), antifungal (against Botrytis cinerea, Septoria tritici and Phytophthora infestans), antibacterial (against Bacillus subtilis and Aliivibrio fischeri), and antiproliferative (against PC-3 and HT-29 human cancer cell lines) activities. The known peperobtusin A (5) was the most active compound against the PC-3 cancer cell line with IC50 values of 25.6 µM and 36.0 µM in MTT and CV assays, respectively. This compound also induced 90% inhibition of bacterial growth of the Gram-positive B. subtilis at a concentration of 100 µM. In addition, compound 3 showed anti-oomycotic activity against P. infestans with an inhibition value of 56% by using a concentration of 125 µM. However, no anthelmintic activity was observed.
Bücher und Buchkapitel
Hussain, H.; Elizbit, .; Ali, I.; Mamadalieva, N. Z.; Abbas, G.; Ali, M.; Zaman, G.; Khan, A.; Hassan, U.; Green, I. R.;Fruitful decade of Phoma secondary metabolites from 2011 to 2020: Chemistry, chemical diversity, and biological activitiesRai, M., Zimowska, B., Kövics, G.J.Phoma: Diversity, Taxonomy, Bioactivities, and Nanotechnology183–203(2022)ISBN:978-3-030-81217-1DOI: 10.1007/978-3-030-81218-8_10
Fungi have been an extraordinary area of scientific research, and many secondary metabolites with intriguing chemical diversity along with interesting biological activities have been identified. Fungi like Phoma sp. have been investigated as a source of structurally unique metabolites over the past 10 years (2011–2020). A diverse range of natural products, viz., α-pyrone derivatives, isocoumarins, anthraquinones, xanthones, thiodiketopiperazines, cytochalasin derivatives, diphenyl ether derivatives, furopyrans, xyloketals, chromones, meroterpenoids, diterpenoids, polyketides, and alkaloids, have been reported from various Phoma spp. These metabolites illustrated phytotoxic, cytotoxic, antibacterial, antifungal, herbicidal, immunosuppressive, antiviral, antidiabetic (PTP1B inhibition), anti-Alzheimer (acetylcholinesterase inhibition), and antioxidant activities.
Publikation
Sultani, H. N.; Morgan, I.; Hussain, H.; Roos, A. H.; Haeri, H. H.; Kaluđerović, G. N.; Hinderberger, D.; Westermann, B.;Access to new cytotoxic triterpene and steroidal Acid-TEMPO Conjugates by ugi multicomponent-reactionsInt. J. Mol. Sci.227125(2021)DOI: 10.3390/ijms22137125
Multicomponent reactions, especially the Ugi-four component reaction (U-4CR), provide powerful protocols to efficiently access compounds having potent biological and pharmacological effects. Thus, a diverse library of betulinic acid (BA), fusidic acid (FA), cholic acid (CA) conjugates with TEMPO (nitroxide) have been prepared using this approach, which also makes them applicable in electron paramagnetic resonance (EPR) spectroscopy. Moreover, convertible amide modified spin-labelled fusidic acid derivatives were selected for post-Ugi modification utilizing a wide range of reaction conditions which kept the paramagnetic center intact. The nitroxide labelled betulinic acid analogue 6 possesses cytotoxic effects towards two investigated cell lines: prostate cancer PC3 (IC50 7.4 ± 0.7 μM) and colon cancer HT29 (IC50 9.0 ± 0.4 μM). Notably, spin-labelled fusidic acid derivative 8 acts strongly against these two cancer cell lines (PC3: IC50 6.0 ± 1.1 μM; HT29: IC50 7.4 ± 0.6 μM). Additionally, another fusidic acid analogue 9 was also found to be active towards HT29 with IC50 7.0 ± 0.3 μM (CV). Studies on the mode of action revealed that compound 8 increased the level of caspase-3 significantly which clearly indicates induction of apoptosis by activation of the caspase pathway. Furthermore, the exclusive mitochondria targeting of compound 18 was successfully achieved, since mitochondria are the major source of ROS generation.
Publikation
Nazir, M.; Saleem, M.; Tousif, M. I.; Anwar, M. A.; Surup, F.; Ali, I.; Wang, D.; Mamadalieva, N. Z.; Alshammari, E.; Ashour, M. L.; Ashour, A. M.; Ahmed, I.; Elizbit, .; Green, I. R.; Hussain, H.;Meroterpenoids: A comprehensive update insight on structural diversity and biologyBiomolecules11957(2021)DOI: 10.3390/biom11070957
Meroterpenoids are secondary metabolites formed due to mixed biosynthetic pathways which are produced in part from a terpenoid co-substrate. These mixed biosynthetically hybrid compounds are widely produced by bacteria, algae, plants, and animals. Notably amazing chemical diversity is generated among meroterpenoids via a combination of terpenoid scaffolds with polyketides, alkaloids, phenols, and amino acids. This review deals with the isolation, chemical diversity, and biological effects of 452 new meroterpenoids reported from natural sources from January 2016 to December 2020. Most of the meroterpenoids possess antimicrobial, cytotoxic, antioxidant, anti-inflammatory, antiviral, enzyme inhibitory, and immunosupressive effects.