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Multi-targets of antimicrobial photodynamic therapy mediated by erythrosine against Staphylococcus aureus identified by proteomic approach. Photochem Photobiol 2024. [PMID: 38594817 DOI: 10.1111/php.13944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 02/13/2024] [Accepted: 03/06/2024] [Indexed: 04/11/2024]
Abstract
Staphylococcus aureus is a global challenge to the clinical field and food industry. Therefore, the development of antimicrobial photodynamic therapy (aPDT) has become one of the valuable methods to control this pathogen. The antibacterial activity of photoinactivation by erythrosine (Ery) against S. aureus has been reported, but its modes of action are unclear. This study aimed to employ a proteomic approach to analyze modes of action of Ery-aPDT against S. aureus. We determined the antibacterial effect by Ery-aPDT assays, quantified reactive oxygen species (ROS) and injury to the cell membrane, and determined protein expression using a proteomic approach combined with bioinformatic tools. Ery-aPDT was effective in reducing S. aureus to undetectable levels. In addition, the increment of ROS accompanied the increase in the reduction of cell viability, and damage to cellular membranes was shown by sublethal injury. In proteomic analysis, we found 17 differentially expressed proteins. These proteins revealed changes mainly associated with defense to oxidative stress, energy metabolism, translation, and protein biosynthesis. Thus, these results suggest that the effectiveness of Ery-aPDT is due to multi-targets in the bacterial cell that cause the death of S. aureus.
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Diversity and Mechanisms of Action of Plant, Animal, and Human Antimicrobial Peptides. Antibiotics (Basel) 2024; 13:202. [PMID: 38534637 DOI: 10.3390/antibiotics13030202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/05/2024] [Accepted: 01/17/2024] [Indexed: 03/28/2024] Open
Abstract
Antimicrobial peptides (AMPs) are usually made up of fewer than 100 amino acid residues. They are found in many living organisms and are an important factor in those organisms' innate immune systems. AMPs can be extracted from various living sources, including bacteria, plants, animals, and even humans. They are usually cationic peptides with an amphiphilic structure, which allows them to easily bind and interact with the cellular membranes of viruses, bacteria, fungi, and other pathogens. They can act against both Gram-negative and Gram-positive pathogens and have various modes of action against them. Some attack the pathogens' membranes, while others target their intracellular organelles, as well as their nucleic acids, proteins, and metabolic pathways. A crucial area of AMP use is related to their ability to help with emerging antibiotic resistance: some AMPs are active against resistant strains and are susceptible to peptide engineering. This review considers AMPs from three key sources-plants, animals, and humans-as well as their modes of action and some AMP sequences.
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Dimeric 3,5-Bis(benzylidene)-4-piperidones: Tumor-Selective Cytotoxicity and Structure-Activity Relationships. MEDICINES (BASEL, SWITZERLAND) 2024; 11:3. [PMID: 38248717 PMCID: PMC10821124 DOI: 10.3390/medicines11010003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 09/23/2023] [Accepted: 12/29/2023] [Indexed: 01/23/2024]
Abstract
Background: The objective of this study is to find novel antineoplastic agents that display greater toxicity to malignant cells than to neoplasms. In addition, the mechanisms of action of representative compounds are sought. This report describes the cytotoxicity of a number of dimers of 3,5-bis(benzylidene)-4-piperidones against human malignant cells (promyelocytic leukemia HL-60 and squamous cell carcinoma HSC-2, HSC-3, and HSC-4). Methods: Tumor specificity was evaluated by the selectivity index (SI), that is the ratio of the mean CC50 for human non-malignant oral cells (gingival fibroblasts, pulp cells, periodontal ligament fibroblasts) to that for malignant cells. Results: The compounds were highly toxic to human malignant cells. On the other hand, these molecules were less toxic to human non-malignant cells. In particular, a potent lead molecule, 3b, was identified. A QSAR study revealed that the placement of electron-releasing and hydrophilic substituents into the aryl rings led to increases in cytotoxic potencies. The modes of action of a lead compound discovered in this study designated 3b were the activation of caspases-3 and -7, as well as causing PARP1 cleavage and G2 arrest, followed by sub-G1 accumulation in the cell cycle. This compound also depolarized the mitochondrial membrane and generated reactive oxygen species in human colon carcinoma HCT116 cells. In conclusion, this study has revealed that, in general, the compounds described in this report are tumor-selective cytotoxins.
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Cutting-edge knowledge on the roles of phytobiotics and their proposed modes of action in swine. Front Vet Sci 2023; 10:1265689. [PMID: 37808106 PMCID: PMC10552858 DOI: 10.3389/fvets.2023.1265689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 09/06/2023] [Indexed: 10/10/2023] Open
Abstract
With the ban on antibiotics in the swine industry, the exploration of alternative options has highlighted phytobiotics as a promising substitute for antibiotic growth promoters, aiming to foster a more sustainable swine industry. Phytobiotics are non-nutritive natural bioactive components derived from plants that offer numerous health benefits. They exhibit antioxidative, antimicrobial, and anti-inflammatory effects. Phytobiotics can be utilized in various forms, including solid, dried, ground, or as extracts, either in crude or concentrated form. They are characterized by low residual levels, a lack of resistance development, and minimal adverse effects. These qualities make phytobiotics an attractive choice for enhancing health and productivity in swine, presenting them as a viable alternative to antibiotics. While there is a general understanding of the effects of phytobiotics, there is still a need for detailed information regarding their effectiveness and mechanisms of action in practical settings. Therefore, the purpose of this mini review was to summarize the current knowledge supporting the roles of phytobiotics and their proposed modes of action, with a specific focus on swine.
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Small Cationic Cysteine-Rich Defensin-Derived Antifungal Peptide Controls White Mold in Soybean. J Fungi (Basel) 2023; 9:873. [PMID: 37754982 PMCID: PMC10532163 DOI: 10.3390/jof9090873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/11/2023] [Accepted: 08/22/2023] [Indexed: 09/28/2023] Open
Abstract
White mold disease caused by a necrotrophic ascomycete pathogen Sclerotinia sclerotiorum results in serious economic losses of soybean yield in the USA. Lack of effective genetic resistance to this disease in soybean germplasm and increasing pathogen resistance to fungicides makes white mold difficult to manage. Small cysteine-rich antifungal peptides with multi-faceted modes of action possess potential for development as sustainable spray-on bio-fungicides. We have previously reported that GMA4CG_V6 peptide, a 17-amino acid variant of the MtDef4 defensin-derived peptide GMA4CG containing the active γ-core motif, exhibits potent antifungal activity against the gray mold fungal pathogen Botrytis cinerea in vitro and in planta. GMA4CG_V6 exhibited antifungal activity against an aggressive field isolate of S. sclerotiorum 555 in vitro with an MIC value of 24 µM. At this concentration, internalization of this peptide into fungal cells occurred prior to discernible membrane permeabilization. GMA4CG_V6 markedly reduced white mold disease symptoms when applied to detached soybean leaves, pods, and stems. Its spray application on soybean plants provided robust control of this disease. GMA4CG_V6 at sub-lethal concentrations reduced sclerotia production. It was also non-phytotoxic to soybean plants. Our results demonstrate that GMA4CG_V6 peptide has potential for development as a bio-fungicide for white mold control in soybean.
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Plant defensin MtDef4-derived antifungal peptide with multiple modes of action and potential as a bio-inspired fungicide. MOLECULAR PLANT PATHOLOGY 2023; 24:896-913. [PMID: 37036170 PMCID: PMC10346373 DOI: 10.1111/mpp.13336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 02/28/2023] [Accepted: 03/20/2023] [Indexed: 06/19/2023]
Abstract
Chemical fungicides have been instrumental in protecting crops from fungal diseases. However, increasing fungal resistance to many of the single-site chemical fungicides calls for the development of new antifungal agents with novel modes of action (MoA). The sequence-divergent cysteine-rich antifungal defensins with multisite MoA are promising starting templates for design of novel peptide-based fungicides. Here, we experimentally tested such a set of 17-amino-acid peptides containing the γ-core motif of the antifungal plant defensin MtDef4. These designed peptides exhibited antifungal properties different from those of MtDef4. Focused analysis of a lead peptide, GMA4CG_V6, showed that it was a random coil in solution with little or no secondary structure elements. Additionally, it exhibited potent cation-tolerant antifungal activity against the plant fungal pathogen Botrytis cinerea, the causal agent of grey mould disease in fruits and vegetables. Its multisite MoA involved localization predominantly to the plasma membrane, permeabilization of the plasma membrane, rapid internalization into the vacuole and cytoplasm, and affinity for the bioactive phosphoinositides phosphatidylinositol 3-phosphate (PI3P), PI4P, and PI5P. The sequence motif RRRW was identified as a major determinant of the antifungal activity of this peptide. While topical spray application of GMA4CG_V6 on Nicotiana benthamiana and tomato plants provided preventive and curative suppression of grey mould disease symptoms, the peptide was not internalized into plant cells. Our findings open the possibility that truncated and modified defensin-derived peptides containing the γ-core sequence could serve as promising candidates for further development of bio-inspired fungicides.
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Editorial: Bioaccessibility of food-derived bioactive components and their health-promoting mechanisms. Front Nutr 2023; 10:1191671. [PMID: 37266133 PMCID: PMC10231672 DOI: 10.3389/fnut.2023.1191671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/05/2023] [Indexed: 06/03/2023] Open
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Indigenous Yeasts for the Biocontrol of Botrytis cinerea on Table Grapes in Chile. J Fungi (Basel) 2023; 9:jof9050557. [PMID: 37233268 DOI: 10.3390/jof9050557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/20/2023] [Accepted: 05/08/2023] [Indexed: 05/27/2023] Open
Abstract
One hundred twenty-five yeast strains isolated from table grapes and apples were evaluated for the control Botrytis cinerea of in vitro and in vivo. Ten strains were selected for their ability to inhibit mycelial growth of B. cinerea in vitro. In the in vivo assays, these yeasts were tested at 20 °C on 'Thompson Seedless' berries for 7 days; only three were selected (m11, me99 and ca80) because they significantly reduced the incidence of gray mold. These three yeast strains were then evaluated at different concentrations (1 × 107, 1 × 108 and 1 × 109 cells mL-1) on 'Thompson Seedless' grape berries at 20 °C. The strains m11, me99 and ca80 reduced the incidence of B. cinerea to 11.9, 26.1 and 32.1%, respectively, when the berries were submerged in a yeast suspension at a concentration of 1 × 109 cells mL-1 24 h before inoculation with B. cinerea. The most favorable pH for antifungal activity was 4.6 in the three isolates. The three yeast strains secreted the hydrolytic enzymes chitinase and β-1-glucanase, and two strains (me99 and ca80) produced siderophores. The three yeast strains exhibited low oxidative stress tolerance and only strain m11 had the ability to produce biofilms. The strains were identified using 5.8S-ITS rDNA PCR-RFLP and correspond to the Meyerozyma guilliermondii (m11) and Aureobasidium pullulans (me99 and ca80) species.
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3-Hydroxy-2-oxindole Derivatives Containing Sulfonamide Motif: Synthesis, Antiviral Activity, and Modes of Action. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:267-275. [PMID: 36537356 DOI: 10.1021/acs.jafc.2c06881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
3-Hydroxy-2-oxindole motif constitutes a core structure in numerous natural products and imparts notable biological activities. Here, we describe the design and synthesis of four series of novel 3-substituted-3-hydroxy-2-oxindole derivatives containing sulfonamide moiety along with their antiviral activities against potato virus Y (PVY). Compound 10b displayed optimal antiviral activity and superior anti-PVY activity compared with the lead compound and commercial Ningnanmycin in terms of curative and protective effects. Additionally, 10b considerably inhibited PVY systemic infection in Nicotiana benthamiana. Physiological and biochemical analyses revealed that the activities of the four crucial defense-related enzymes increased in the tobacco plant following treatment with 10b. RNA-sequencing analysis revealed that 10b substantially induced the upregulation of 38 differentially expressed genes, which were enriched in the photosynthesis pathway. These findings suggest that 10b is a promising antiviral agrochemical that can effectively control PVY infection and trigger plant host immunity to develop virus resistance. This study provides novel molecular entities and ideas for developing new pesticides.
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Antibacterial Peptide NP-6 Affects Staphylococcus aureus by Multiple Modes of Action. Int J Mol Sci 2022; 23:ijms23147812. [PMID: 35887160 PMCID: PMC9319634 DOI: 10.3390/ijms23147812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/30/2022] [Accepted: 07/13/2022] [Indexed: 02/01/2023] Open
Abstract
Our previous study extracted and identified an antibacterial peptide that was named NP-6. Herein, we investigated the physicochemical properties of NP-6, and elucidated the mechanisms underlying its antimicrobial activity against Staphylococcus aureus. The results showed that the hemolysis activity of NP-6 was 2.39 ± 0.13%, lower than Nisin A (3.91 ± 0.43%) at the same concentration (512 µg/mL). Negligible cytotoxicity towards RAW264.7 cells was found when the concentration of NP-6 was lower than 512 µg/mL. In addition, it could keep most of its activity in fetal bovine serum. Moreover, transmission electron microscopy, confocal laser scanning microscopy, and flow cytometry results showed that NP-6 can destroy the integrity of the bacterial cell membrane and increase the membrane permeability. Meanwhile, NP-6 had binding activity with bacterial DNA and RNA in vitro and strongly inhibited the intracellular β-galactosidase activity of S. aureus. Our findings suggest that NP-6 could be a promising candidate against S. aureus.
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Pharmacological Effects of Cisplatin Combination with Natural Products in Cancer Chemotherapy. Int J Mol Sci 2022; 23:ijms23031532. [PMID: 35163459 PMCID: PMC8835907 DOI: 10.3390/ijms23031532] [Citation(s) in RCA: 55] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 01/20/2022] [Accepted: 01/24/2022] [Indexed: 12/20/2022] Open
Abstract
Cisplatin and other platinum-based drugs, such as carboplatin, ormaplatin, and oxaliplatin, have been widely used to treat a multitude of human cancers. However, a considerable proportion of patients often relapse due to drug resistance and/or toxicity to multiple organs including the liver, kidneys, gastrointestinal tract, and the cardiovascular, hematologic, and nervous systems. In this study, we sought to provide a comprehensive review of the current state of the science highlighting the use of cisplatin in cancer therapy, with a special emphasis on its molecular mechanisms of action, and treatment modalities including the combination therapy with natural products. Hence, we searched the literature using various scientific databases., such as MEDLINE, PubMed, Google Scholar, and relevant sources, to collect and review relevant publications on cisplatin, natural products, combination therapy, uses in cancer treatment, modes of action, and therapeutic strategies. Our search results revealed that new strategic approaches for cancer treatment, including the combination therapy of cisplatin and natural products, have been evaluated with some degree of success. Scientific evidence from both in vitro and in vivo studies demonstrates that many medicinal plants contain bioactive compounds that are promising candidates for the treatment of human diseases, and therefore represent an excellent source for drug discovery. In preclinical studies, it has been demonstrated that natural products not only enhance the therapeutic activity of cisplatin but also attenuate its chemotherapy-induced toxicity. Many experimental studies have also reported that natural products exert their therapeutic action by triggering apoptosis through modulation of mitogen-activated protein kinase (MAPK) and p53 signal transduction pathways and enhancement of cisplatin chemosensitivity. Furthermore, natural products protect against cisplatin-induced organ toxicity by modulating several gene transcription factors and inducing cell death through apoptosis and/or necrosis. In addition, formulations of cisplatin with polymeric, lipid, inorganic, and carbon-based nano-drug delivery systems have been found to delay drug release, prolong half-life, and reduce systemic toxicity while other formulations, such as nanocapsules, nanogels, and hydrogels, have been reported to enhance cell penetration, target cancer cells, and inhibit tumor progression.
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Antiviral Peptides with in vivo Activity: Development and Modes of Action. Chempluschem 2021; 86:1547-1558. [PMID: 34755499 DOI: 10.1002/cplu.202100351] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 10/28/2021] [Indexed: 12/25/2022]
Abstract
The viral pandemic has resulted in a growing demand for antiviral drugs. The existing small-molecule antiviral drugs are limited, due to their incidence of drug resistance and adverse side effects. As potential drugs, antiviral peptides have the benefits of high activity, high stability, and few side effects. Furthermore, the diversity of acquisition methods allows antiviral peptides to be quickly designed and yielded. The drug properties (such as high bioavailability and in vivo stability) of antiviral peptides can be improved by the developed modifications. Currently, two peptide antiviral drugs have been approved for the treatment of acquired immunodeficiency syndrome (AIDS). Many antiviral peptides have entered clinical trials for the treatment of diseases caused by viruses. In addition, new antiviral peptides are continuously being identified and validated against virus infections. Given the benefits of antiviral peptides, they will become major antiviral drugs to combat new outbreaks caused by unknown viruses in the future. This review provides an overview of recent developments in antiviral peptides with in vivo activity.
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Broad-spectrum antifungal activity of lipopeptide brevilaterin B and its inhibition effects against Fusarium oxysporum and Penicillium chrysogenum. J Appl Microbiol 2021; 132:1330-1342. [PMID: 34480826 DOI: 10.1111/jam.15285] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/25/2021] [Accepted: 08/31/2021] [Indexed: 01/18/2023]
Abstract
AIMS Brevilaterin B is a natural antimicrobial lipopeptide produced by Brevibacillus laterosporus S62-9. However, its antifungal spectrum and modes of action are still unclear. Herein, we investigated the detailed antifungal activity of brevilaterin B against 33 pathogenic fungi and the antifungal effects against two sensitive fungi in vitro and in vivo. METHODS AND RESULTS Brevilaterin B exhibited inhibitory activity against 33 pathogenic fungi involved in plant disease and food spoilage at the minimum inhibitory concentrations (MICs) range of 16-128 μg ml-1 . The antifungal effects were further studied by Fusarium oxysporum and Penicillium chrysogenum. Both spore germination and mycelium growth were inhibited by brevilaterin B at sub-MIC. Transmission electron microscopy and fluorescent dye staining assays indicated brevilaterin B damaged cell integrity and induced apoptosis. In vivo tests, brevilaterin B inhibited the infection of F. oxysporum to Dendrobium officinale and P. chrysogenum to mandarin (Citrus reticulata) at 500 μg ml-1 , respectively. CONCLUSIONS Brevilaterin B showed broad-spectrum antifungal activity against 33 pathogenic fungi. And its antifungal modes of action were proposed as damaging cell integrity and inducing cell apoptosis. The lipopeptide is promising to control F. oxysporum in the D. officinale and P. chrysogenum in the mandarin. SIGNIFICANCE AND IMPACT OF STUDY The research provided insights into antifungal modes of action of brevilaterin B. The lipopeptide brevilaterin B is potential to be developed as a broad-spectrum antifungal agent for agricultural biocontrol and postharvest storage.
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The European Federation for Medicinal Chemistry and Chemical Biology (EFMC) Best Practice Initiative: Phenotypic Drug Discovery. ChemMedChem 2021; 16:1736-1739. [PMID: 33825353 DOI: 10.1002/cmdc.202100041] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Indexed: 12/16/2022]
Abstract
Phenotypic drug discovery has a long track record of delivering innovative drugs and has received renewed attention in the last few years. The promise of this approach, however, comes with several challenges that should be addressed to avoid wasting time and resources on drugs with undesired modes of action or, worse, false-positive hits. In this set of best practices, we go over the essential steps of phenotypic drug discovery and provide guidance on how to increase the chance of success in identifying validated and relevant chemical starting points for optimization: selecting the right assay, selecting the right compound screening library and developing appropriate hit validation assays. Then, we highlight the importance of initiating studies to determine the mode of action of the identified hits early and present the current state of the art.
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Plukenetia huayllabambana Fruits: Analysis of Bioactive Compounds, Antibacterial Activity and Relative Action Mechanisms. PLANTS 2020; 9:plants9091111. [PMID: 32872157 PMCID: PMC7569793 DOI: 10.3390/plants9091111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 12/15/2022]
Abstract
Plukenetia huayllabambana is an edible plant traditionally used to cure wounds and various infections. The present work assessed, for the first time, the antibacterial efficacy of solvent fractions from P. huayllabambana fruits. The crude methanol extract was obtained applying ultrasound-assisted extraction, followed by partitioning through successive depletion among solvents of increasing polarity to yield fractions (n-hexane, dichloromethane, ethyl acetate, and n-butanol). The minimal inhibitory concentration (MIC) was determined following antibacterial testing, using the broth microdilution technique against a panel of drug-resistant Gram-negative and Gram-positive bacteria. Possible modes of action of the most active fraction were also investigated. Gas chromatography-mass spectrometry (GC-MS) was used to identify phytocompounds that may account for the recorded activities. Methanol, n-hexane (PH-n-Hex), and ethyl acetate extracts inhibited 100% of studied bacteria, with the recorded MIC ranging from 0.125-1 mg/mL. PH-n-Hex appeared as the most active partition, exerting a bacteriostatic effect. PH-n-Hex probably acts by interfering with bacterial biofilm formation, proton pumps, and bacterial cell membrane integrity. The GC-MS analysis of PH-n-Hex led to the identification of 11 potentially bioactive components, including fatty acids, phytosterol, and diterpene alcohol as major ones. P. huayllabambana can be considered as a plant of pharmacological value-a source of potent anti-infective drug entities.
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Herbicidal Secondary Metabolites from Actinomycetes: Structure Diversity, Modes of Action, and Their Roles in the Development of Herbicides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:17-32. [PMID: 31809036 DOI: 10.1021/acs.jafc.9b06126] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Weeds had caused significant loss for crop production in the process of agriculture. Herbicides have played an important role in securing crop production. However, the high reliance on herbicides has led to environmental issues as well as the evolution of herbicide resistance. Thus, there is an urgent need for new herbicides with safer toxicological profiles and novel modes of action. Actinomycetes produce very diverse bioactive compounds, of which some show potent biopesticidal activity. The herbicidal secondary metabolites from actinomycetes can be classified into several groups, such as amino acids, peptides, nucleosides, macrolides, lactones, amide, amines, etc., some of which have been successfully developed as commercial herbicides. The structure diversity and evolved biological activity of secondary metabolites from actinomycetes can offer opportunities for the development of both directly used bioherbicides and synthetic herbicides with new target sites, and thus, this review focuses on the structure, herbicidal activity, and modes of action of secondary metabolites from actinomycetes.
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Antifungal Potency and Modes of Action of a Novel Olive Tree Defensin Against Closely Related Ascomycete Fungal Pathogens. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:1649-1664. [PMID: 31425003 DOI: 10.1094/mpmi-08-19-0224-r] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Antimicrobial peptides play a pivotal role in the innate immunity of plants. Defensins are cysteine-rich antifungal peptides with multiple modes of action. A novel Oleaceae-specific defensin gene family has been discovered in the genome sequences of wild and cultivated species of a perennial olive tree, Olea europaea. OefDef1.1, a member of this defensin family, potently inhibits the in-vitro growth of ascomycete fungal pathogens Botrytis cinerea and three Fusarium spp. OefDef1.1 rapidly permeabilizes the plasma membrane of the conidial and germling cells of B. cinerea. Interestingly, it induces reactive oxygen species and translocates to the cytoplasm only in the germlings but not in the conidia. In medium containing a high concentration of Na1+, antifungal activity of OefDef1.1 is significantly reduced. Surprisingly, a chimeric OefDef1.1 peptide containing the γ-core motif of a Medicago truncatula defensin, MtDef4, displays Na1+-tolerant antifungal activity. In a phospholipid-protein overlay assay, the chimeric peptide exhibits stronger binding to its phosphoinositide partners than OefDef1.1 and is also more potent in inhibiting gray mold disease on the surface of Nicotiana benthamiana and lettuce leaves than OefDef1.1. Significant differences are observed among the four ascomycete pathogens in their responses to OefDef1.1 in growth medium with or without the elevated concentration of Na1+. The varied responses of closely related ascomycete pathogens to this defensin have implications for engineering disease resistance in plants.
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Medicinal and Therapeutic Potential of Herbs and Plant Metabolites / Extracts Countering Viral Pathogens - Current Knowledge and Future Prospects. Curr Drug Metab 2018; 19:236-263. [PMID: 29380697 DOI: 10.2174/1389200219666180129145252] [Citation(s) in RCA: 131] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 05/08/2017] [Accepted: 12/19/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Recently, there has been a remarkable progress in the field of antiviral herbal therapy owing to increasing concerns about the development of drug resistance and limited advances in the field of antiviral drug discovery. In almost all countries, medicinal plants have been used widely throughout history for the treatment of diseases and infections as traditional healing remedies due to their broad therapeutic spectrum and minimal or no side effects. As synthetic antiviral drugs are not available against most of the viral agents, hence all possible efforts have been focused on the search for new drugs and complementary/alternative medicines from different herbal formulations. METHODS We have retrieved the related information from the online published resources (Medline, PubMed, Pub- Med Central, Science Direct and other scientific databases); which were further analyzed and compiled. RESULTS Medicinal plants contain extractable biochemical and bioactive compounds, which can target certain viruses or can cure or prevent several viral diseases and infections. Despite their long history of use, the research and scientific evidences regarding the use of medicinal plants and natural products as prophylactics, therapeutics, and their health multiple beneficial applications have only gained momentum in past few decades. Many scientific studies have been undertaken, which range from the separation of active substances to the comprehension of the therapeutic mechanisms of antiviral herbs, their potent applications in the neutralization of viral pathogens and clinical trials. Consequently, hundreds of herbs and plant metabolites have been screened, identified, and tested for their antiviral activities; fortunately, some have shown significant medicinal activity in the amelioration or prevention of various viral diseases in both preclinical and clinical studies. CONCLUSION This review addresses the scientific significance of various herbal formulations of different medicinal plants and their extracts, which have shown promise or been proven effective for the treatment of diseases caused by various viral pathogens, including emerging and re-emerging viruses that infect humans, animals, poultry and fish.
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Investigation of the Antifungal Activity and Mode of Action of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimum basilicum, and Eugenia caryophyllus Essential Oils. Molecules 2018; 23:E1116. [PMID: 29738503 PMCID: PMC6099571 DOI: 10.3390/molecules23051116] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 04/29/2018] [Accepted: 05/01/2018] [Indexed: 11/16/2022] Open
Abstract
The antimicrobial activity of plant oils and extracts has been recognized for many years. In this study the activity of Thymus vulgaris, Citrus limonum, Pelargonium graveolens, Cinnamomum cassia, Ocimumbasilicum, and Eugenia caryophyllus essential oils (EOs) distributed by Pollena Aroma (Nowy Dwór Mazowiecki, Poland) was investigated against a group of 183 clinical isolates of C. albicans and 76 isolates of C. glabrata. All of the oils exhibited both fungistatic and fungicidal activity toward C. albicans and C. glabrata isolates. The highest activity was observed for cinnamon oil, with MIC (Minimum Inhibitory Concentration) values in the range 0.002⁻0.125% (v/v). The MIC values of the rest of the oils were in the range 0.005% (or less) to 2.5% (v/v). In most cases MFC (Minimum Fungicidal Concentration) values were equal to MIC or twice as high. Additionally, we examined the mode of action of selected EOs. The effect on cell wall components could not be clearly proved. Three of the tested EOs (thyme, lemon, and clove) affected cell membranes. At the same time, thyme, cinnamon, and clove oil influenced potassium ion efflux, which was not seen in the case of lemon oil. All of the tested oils demonstrated the ability to inhibit the transition of yeast to mycelium form, but the effect was the lowest in the case of cinnamon oil.
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Anti-Inflammatory Drugs and Herbs with Special Emphasis on Herbal Medicines for Countering Inflammatory Diseases and Disorders - A Review. RECENT PATENTS ON INFLAMMATION & ALLERGY DRUG DISCOVERY 2018; 12:39-58. [PMID: 29336271 DOI: 10.2174/1872213x12666180115153635] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 12/26/2017] [Accepted: 11/01/2018] [Indexed: 02/08/2023]
Abstract
BACKGROUND Diseases with inflammatory etiopathology have increased in incidence in recent times. Drugs used for therapeutic management of such inflammatory diseases are relieving the ailment but at the same time also countering serious life threatening consequences. Moreover, they are costly and rarely available at all places. In this context, research and development on medicinal herbs have opened a new era in the prophylactic and therapeutic management of inflammatory diseases. OBJECTIVE To highlight the importance of anti-inflammatory medicine-synthetic drugs and natural herbs, their constituents, mechanism of action, benefits, side effects and future prospects. The overall aim is to provide better health services to patients regardless of their background on equality basis. RESULTS Anti-inflammatory herbs have proven beneficial by combating inflammatory responses that lead to severe abnormality in body systems. Inflammation though a protective response to infection or injury and may result in pathological outcome when aggravated or of severe degree thus needs an early intervention for proper resolution. Medicinal plants or their constituents are considered beneficial due to the properties i.e., satisfactory potency, ease of availability, cheapness, less or no side effects, safer and efficient as compared to the synthetic counterparts. These medicinal herbs contain phytoconstituents that can prevent undesirable inflammatory processes and also posses anti-inflammatory activity. Steroids, glycosides, phenolics, flavonoids, alkaloids, polysaccharides, terpenoids, cannabinoids, fatty acids are common phytoconstituents present in these plants. Different mechanisms have been explored for the anti-inflammatory action of these active ingredients. They may synergize the anti-inflammatory pathway enzymes, factors, proteins or interfere with these in the inflammatory pathway like lipooxygenases, cyclooxygenases, tumor necrosis factors, interleukins, prostaglandin, nitric oxide, mitogenactivated protein, nuclear factor, etc. Considering all the above-mentioned factors, further research from molecular to cellular level will enable a better understanding of the mechanisms. Common antiinflammatory herbal plants are Curcuma longa, Zingiber officinale, Rosmarinus officinalis, Borago officinalis, Urtica dioica, Uncaria tomentosa, Vaccinium myrtillus, Olea europaea and much more. They are believed to be without side effects unlike the chemical counterparts or synthetic anti-inflammatory agents e.g. steroids, nonsteroid anti-inflammatory drugs, and immunosuppresants used for controlling and suppressing inflammatory crisis. A proper phytochemical, pharmacological and physiological evaluation will enable their safe and effective use in inflammatory conditions. Many of these anti-inflammatory drugs and herbal preparations have been patented with some under consideration. CONCLUSION Natural herbs are safe, effective and better options as anti-inflammatory agents than synthetic ones. The phytoconstituents are as effective with the comparable mechanism of action as synthetic molecules. Future research should focus on molecular mechanisms of different beneficial applications of these herbal plants in various diseases. Recent patents on anti-inflammatory drugs and herbal plants have been covered which provide insight into the current status and future prospects in this field.
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Probiotics in Curing Allergic and Inflammatory Conditions - Research Progress and Futuristic Vision. RECENT PATENTS ON INFLAMMATION & ALLERGY DRUG DISCOVERY 2017; 10:105-118. [PMID: 28029082 DOI: 10.2174/1872213x10666161226162229] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 12/22/2016] [Accepted: 12/25/2016] [Indexed: 02/08/2023]
Abstract
BACKGROUND Probiotics constitute the viable and beneficial microbes, which offer a dietary means to sustain the balance of gastro-intestinal (GI) microflora. Owing to their multiple health benefits, these have recently gained wide attention among researchers for exploring their potential in safeguarding the health of humans and animals. Probiotics could also modulate host-immune responses, thereby help in counteracting the immunological dysfunctions. Probiotics can inhibit the systemic invasion of pathogens entering through the GI mucosa/ oral cavity and have been found to possess effective prophylactic and therapeutic utilities against various infectious pathogens as well as non-infectious diseases and disorders. OBJECTIVE The present review expedites the role of probiotics in curing the ailments related to allergic and inflammatory disease conditions. METHOD A thorough reviewing of the literature and patents available on probiotics and their role in countering inflammation and allergy was conducted using authentic published resources available on Medline, PubMed, PubMed Central, Science Direct and other scientific databases. The information retrieved has been compiled and analysed pertaining to the theme of the study. RESULTS Various micro-organisms have been evaluated for their probiotic efficacy, among these, the lactic acid bacteria viz. Lactobacillus sp. and Bifidobacterium sp. have extensively been studied and widely exploited. In the current post-globalized era of self and complementary medicines, the concept of probiotics and their therapeutic as well as prophylactic usage is gaining wide acceptance. As more and more bacterial strains are being proven for their pronounced influence on down regulation of immune regulation, atopic, inflammatory conditions, the use of probiotics is getting increased especially in the developed countries where such indications are high in prevalence. Apart from usage in immune related disorders, probiotics have been found to be effective in treating pouchitis, infantile diarrhoea due to infections, bacterial vaginosis, urinary tract infections, dental carries, diabetes, cancers as well augmenting the gut mucosal tolerance to various antibiotics and lactose intolerance. CONCLUSION The resent review gives an insight towards potent utility of this branch of beneficial microbial therapy in allergy and inflammations, which is still in the emerging phase and more scientific evidences need to be explored regarding exploration of the mechanisms of action, further experimental trials and validation of controlled clinical studies in humans along with designing novel strategies for monitoring the possible microbial changes in their composition and metabolism associated with their interaction upon host immune system.
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Managing the evolution of herbicide resistance. PEST MANAGEMENT SCIENCE 2016; 72:74-80. [PMID: 25809409 PMCID: PMC5029781 DOI: 10.1002/ps.4009] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 02/23/2015] [Accepted: 03/19/2015] [Indexed: 05/10/2023]
Abstract
BACKGROUND Understanding and managing the evolutionary responses of pests and pathogens to control efforts is essential to human health and survival. Herbicide-resistant (HR) weeds undermine agricultural sustainability, productivity and profitability, yet the epidemiology of resistance evolution - particularly at landscape scales - is poorly understood. We studied glyphosate resistance in a major agricultural weed, Amaranthus tuberculatus (common waterhemp), using landscape, weed and management data from 105 central Illinois grain farms, including over 500 site-years of herbicide application records. RESULTS Glyphosate-resistant (GR) A. tuberculatus occurrence was greatest in fields with frequent glyphosate applications, high annual rates of herbicide mechanism of action (MOA) turnover and few MOAs field(-1) year(-1) . Combining herbicide MOAs at the time of application by herbicide mixing reduced the likelihood of GR A. tuberculatus. CONCLUSIONS These findings illustrate the importance of examining large-scale evolutionary processes at relevant spatial scales. Although measures such as herbicide mixing may delay GR or other HR weed traits, they are unlikely to prevent them. Long-term weed management will require truly diversified management practices that minimize selection for herbicide resistance traits.
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