Hanène Zater1, Joëlle Huet2, Véronique Fontaine3, Samir Benayache4, Caroline Stévigny5, Pierre Duez6, Fadila Benayache7. 1. Unité de recherche: Valorisation des Ressources Naturelles, Molécules Bioactives et Analyses Physicochimiques et Biologiques (VARENBIOMOL), Faculté des Sciences Exactes, Université Frères Mentouri Constantine 1, 25000 Constantine, Algeria; Université Ziane Achour, Cité du 5 Juillet, Route Moudjbara BP: 3117, 17000 Djelfa, Algeria; Laboratoire de Pharmacognosie, de Bromatologie et de Nutrition Humaine, Université Libre de Bruxelles (ULB), 1050 Bruxelles, Belgium. 2. Laboratoire de Biopolymère et Nanomatériaux Supramoléculaire, Université Libre de Bruxelles (ULB), 1050 Bruxelles, Belgium. 3. Unité de Microbiologie Pharmaceutique et Hygiène, Faculté de Pharmacie, Université Libre de Bruxelles (ULB), 1050 Bruxelles, Belgium. 4. Unité de recherche: Valorisation des Ressources Naturelles, Molécules Bioactives et Analyses Physicochimiques et Biologiques (VARENBIOMOL), Faculté des Sciences Exactes, Université Frères Mentouri Constantine 1, 25000 Constantine, Algeria. 5. Laboratoire de Pharmacognosie, de Bromatologie et de Nutrition Humaine, Université Libre de Bruxelles (ULB), 1050 Bruxelles, Belgium. 6. Laboratoire de Pharmacognosie, de Bromatologie et de Nutrition Humaine, Université Libre de Bruxelles (ULB), 1050 Bruxelles, Belgium; Service de Chimie Thérapeutique et de Pharmacognosie, Université de Mons (UMONS), 7000 Mons, Belgium. Electronic address: pierre.duez@umons.ac.be. 7. Unité de recherche: Valorisation des Ressources Naturelles, Molécules Bioactives et Analyses Physicochimiques et Biologiques (VARENBIOMOL), Faculté des Sciences Exactes, Université Frères Mentouri Constantine 1, 25000 Constantine, Algeria. Electronic address: fbenayache@yahoo.fr.
Abstract
OBJECTIVE: To investigate the chemical composition of a moderately polar extract (CHCl3 soluble part of the MeOH-H2O extract) obtained from the aerial parts (leaves and flowers) of Centaurea diluta Ait. subsp. algeriensis (Coss. & Dur.) Maire, a species endemic to Algeria and Morocco on which no reports are available to date. To evaluate in vitro the cytotoxic, antifungal and antimicrobial activities of this extract and the cytotoxic and antimicrobial activities of its isolated secondary metabolites. METHODS: The cytotoxic effects of the extract were investigated on 3 human cancer cell lines i.e. the A549 non-small-cell lung carcinoma (NSCLC), the MCF7 breast adenocarcinoma and the U373 glioblastoma using a MTT colorimetric assay. Biological data allowed to guide the fractionation of the extract by separation and purification on silica gel 60 (CC and TLC). The isolated compounds which were characterized by spectral analysis, mainly HR-ESIMS, HR-EIMS, UV and NMR experiments ((1)H, (13)C, COSY, ROESY, HSQC and HMBC) and comparison of their spectroscopic data with those reported in the literature, were evaluated for cytotoxic activities on six cancer cell lines (A549, MCF7, U373, Hs683 human glioma, PC3 human prostate and B16-F10 murine melanoma). The direct and indirect antibacterial and antifungal activities were determined using microdilution methods for the raw extract and TLC-bioautography and microdilution methods against standard and clinical strains for the isolated compounds. RESULTS: The raw extract reduced cell viability with IC50s of 27, 25 and 21 μg/mL on A549, MCF7 and U373, respectively. Five secondary metabolites: two phenolic compounds (vanillin 1, paridol 3), a lignan [(-)-arctigenin 2] and two flavonoid aglycones (eupatilin 4 and jaceosidin 5), were then isolated from this extract. Moderate cytotoxic effects were observed for (-)-arctigenin 2 (IC50s: 28 and 33 μM on Hs683 and B16-F10, respectively), eupatilin 4 (IC50s: 33 and 47 μM on B16-F10 and PC3, respectively) and jaceosidin 5 (IC50s: 32 and 40 μM on PC3 and B16-F10, respectively). CONCLUSIONS: All the isolated compounds were described for the first time from this species. Although inactive against 7 tested microorganisms (fungi, bacteria and yeast, human or plant pathogens), the raw extract was able to potentiate the effect of beta-lactam antibiotics on methicillin-resistant Staphylococcus aureus (MRSA), reducing the minimal inhibitory concentrations (MICs) by a factor of 2-32-fold. No synergy was found between the extract and streptomycin. From the five isolated compounds only jaseosidin 5 showed a moderate antimicrobial activity.
OBJECTIVE: To investigate the chemical composition of a moderately polar extract (CHCl3 soluble part of the MeOH-H2O extract) obtained from the aerial parts (leaves and flowers) of Centaurea diluta Ait. subsp. algeriensis (Coss. & Dur.) Maire, a species endemic to Algeria and Morocco on which no reports are available to date. To evaluate in vitro the cytotoxic, antifungal and antimicrobial activities of this extract and the cytotoxic and antimicrobial activities of its isolated secondary metabolites. METHODS: The cytotoxic effects of the extract were investigated on 3 humancancer cell lines i.e. the A549 non-small-cell lung carcinoma (NSCLC), the MCF7 breast adenocarcinoma and the U373 glioblastoma using a MTT colorimetric assay. Biological data allowed to guide the fractionation of the extract by separation and purification on silica gel 60 (CC and TLC). The isolated compounds which were characterized by spectral analysis, mainly HR-ESIMS, HR-EIMS, UV and NMR experiments ((1)H, (13)C, COSY, ROESY, HSQC and HMBC) and comparison of their spectroscopic data with those reported in the literature, were evaluated for cytotoxic activities on six cancer cell lines (A549, MCF7, U373, Hs683 humanglioma, PC3human prostate and B16-F10 murinemelanoma). The direct and indirect antibacterial and antifungal activities were determined using microdilution methods for the raw extract and TLC-bioautography and microdilution methods against standard and clinical strains for the isolated compounds. RESULTS: The raw extract reduced cell viability with IC50s of 27, 25 and 21 μg/mL on A549, MCF7 and U373, respectively. Five secondary metabolites: two phenolic compounds (vanillin 1, paridol 3), a lignan [(-)-arctigenin 2] and two flavonoid aglycones (eupatilin 4 and jaceosidin 5), were then isolated from this extract. Moderate cytotoxic effects were observed for (-)-arctigenin 2 (IC50s: 28 and 33 μM on Hs683 and B16-F10, respectively), eupatilin 4 (IC50s: 33 and 47 μM on B16-F10 and PC3, respectively) and jaceosidin 5 (IC50s: 32 and 40 μM on PC3 and B16-F10, respectively). CONCLUSIONS: All the isolated compounds were described for the first time from this species. Although inactive against 7 tested microorganisms (fungi, bacteria and yeast, human or plant pathogens), the raw extract was able to potentiate the effect of beta-lactam antibiotics on methicillin-resistant Staphylococcus aureus (MRSA), reducing the minimal inhibitory concentrations (MICs) by a factor of 2-32-fold. No synergy was found between the extract and streptomycin. From the five isolated compounds only jaseosidin 5 showed a moderate antimicrobial activity.
Authors: Jimena Borgo; Laura C Laurella; Florencia Martini; Cesar A N Catalán; Valeria P Sülsen Journal: Molecules Date: 2021-05-06 Impact factor: 4.411
Authors: Eman H Reda; Zienab T Abdel Shakour; Ali M El-Halawany; El-Sayeda A El-Kashoury; Khaled A Shams; Tarik A Mohamed; Ibrahim Saleh; Abdelsamed I Elshamy; Mohamed A M Atia; Ahmed A El-Beih; Nahla S Abdel-Azim; Hesham R El-Seedi; Mohamed-Elamir F Hegazy Journal: Antibiotics (Basel) Date: 2021-03-03