Antimicrobial and Antioxidant Activities of Natural Compounds
Antimicrobial and Antioxidant Activities of Natural Compounds
Letizia Angiolella,1 Gianni Sacchetti,2 and Thomas Efferth3
1Department of Public Health and Infectious Diseases, Sapienza, Università di Roma, Rome, Italy
2Department of Life Sciences and Biotechnology, University of Ferrara, Ferrara, Italy
3Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Johannes Gutenberg University, Mainz, Germany
Correspondence should be addressed to Letizia Angiolella;
Received 1 April 2018; Accepted 1 April 2018; Published 6 June 2018
Copyright © 2018 Letizia Angiolella et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Since ancient times, medicinal plants have traditionally been used for the treatment of different diseases. Nowadays, plants are considered a valuable source of unique natural compounds used in the development of antidiabetic, anti-inflammatory, anticancerous, and antimicrobial drugs. Bacteria, fungi, and viruses are responsible for a range of human diseases. Microbial invasion and its virulence can cause damage to the host cells. Effective antimicrobials have been developed over the years; however, a dramatic increase in resistance to antimicrobial drugs has been observed. The resistance to these drugs has also led to the reemergence of old infectious diseases. Oxidative stress is characterized as an imbalance between the production of reactive species and antioxidant defense activity, and its enhanced state has been associated with many of the chronic diseases such as cancer, diabetes, and neurodegenerative and cardiovascular diseases. Many studies have investigated the antioxidant properties of natural products, but, despite the large number of natural products that are currently studied, the search for new natural compounds with antimicrobial and antioxidant activities still remains a growing research area.
Our special issue, which had opened for 6 months in the second half of 2017, focused on highlighting the recent research on new trends and on new antimicrobial and antioxidant natural compounds obtained from medicinal plants. There were both in vitro and in vivo studies with the aim of relating antimicrobial and antioxidant properties of extracts, fractions, synergistic mixtures, and single pure compounds to possible treatments of human disorders and diseases.
W. A. S. S. Weerakoon et al. evaluated Antioxidant Potentials of Sudarshana Powder through in vitro and in vivo approaches. Antioxidant effects were checked in vitro by ABTS assay, while the Lipid Peroxidation (LPO) in serum was used to detect in vivo activities. ABTS assay revealed that the in vitro antioxidant activity of Sudarshana Powder was equivalent to 14.45 μg of standard Trolox® corresponding to an inhibition percentage of the radical formation of 50.93 ± 0.53%. Furthermore, Sudarshana Powder showed in vivo a significant () decrease in the serum level of thiobarbituric acid reactive substance when compared with the control group. The conclusion of the research is that Sudarshana Powder evidenced biological properties in vitro and in vivo that may attest its health value as traditional product.
P. Cheypratub et al. demonstrated the antibacterial activity and mode of actions of Cyperus rotundus extract (CRE) against ampicillin-resistant Staphylococcus aureus (ARSA) which poses a serious problem for hospitalized patients. The Minimum inhibitory concentrations (MICs) for ampicillin and CRE against all ARSA strains were 64 μg/ml and 0.5 mg/ml, respectively. Checkerboard assay revealed synergistic activity in the combination of ampicillin and CRE at the lowest fractional inhibitory concentration index (FICI) at 0.27. The killing curve assay had confirmed the synergistic and bactericidal activity of the combination against ARSA. This combination caused peptidoglycan and cytoplasmic membrane (CM) damage and an increase in CM permeability of ARSA. So, this CRE proposes the potential to develop a novel adjunct phytopharmaceutical to ampicillin for the remedy of ARSA.
H. O. Elansary et al. described the phenolic profile of the medicinal plants Asparagus aethiopicus L., Citrullus colocynthis L., Senna alexandrina L., Kalanchoe delagoensis L., Gasteria pillansii L., Cymbopogon citratus, Brassica juncea, and Curcuma longa L. In particular these plants were rich sources of important compounds such as robinin in the fruits and leaves of A. aethiopicus; caffeic acid in the tubers of A. aethiopicus; quercitrin in the leaves of G. pillansii; benzoic acid in the pods of S. alexandrina; phenylalanine in the fruit coat and seeds of C. colocynthis; hydroxycaffeic acid in the fruits of C. colocynthis and roots of C. longa; trifoline in the leaves of K. delagoensis; rutin in the leaves of C. citratus; and esculin in the seeds of B. juncea. Further, (...truncated)
