Antimicrobial susceptibility of anaerobic bacteriaIn-vitro evaluation of marine derived fungi against Cutibacterium acnes
Introduction
Acne vulgaris, commonly known as acne or pimples, is the most common skin disorder and it is characterized by inflammation of the sebaceous glands. It affects approximately 50 million people in the US, and many more throughout the world. Globally, more than 80% of the population suffer from acne at some stage in their life [1]. Acne can be extremely painful and causes lasting marks or scars as well as leads to psychosocial suffering [2]. Four factors including androgen-mediated stimulation of sebaceous gland activity, follicular hyper keratinization, colonization of the bacterium C. acnes, and inflammation, play important roles in the pathogenesis of acne [3]. In addition to C. acnes, as the main causative bacteria, S. epidermidis is also present in acne lesions [4]. Economically, it is estimated that US consumers spend more than 1.2 billion dollars each year for the treatment of acne [5]. Over a 10-year period the occurrence of skin colonization by antibiotic-resistant C. acnes in acne patients showed that the proportion of patients with strains resistant to one or more commonly used anti-acne antibiotics is increasing [6]. Given the trend of increased multidrug resistance, there is an urgent need to discover and development of promising new antimicrobials.
Marine natural products are an important source of drug leads [7], [8], [9]. Marine fungi are a valuable marine bioresource because of their abundant diversity and ability to produce chemically diverse secondary metabolites. In the last decade, thousands of novel bioactive compounds from marine fungi have been discovered that possess various pharmacological activities, including cytotoxic, anticancer, antiviral, antibacterial or antifungal activities [10], [11], [12]. Reports of antibacterial compounds from marine fungi have quickly increased since 2010, and marine fungi have been an important natural source of natural antibiotics [13]. For instance, an essential antibacterial indole-alkaloid was isolated from Aspergillus flavus OUCMDZ-2205, which exhibited strong activity against Staphylococcus aureus (MIC, 20.5 μM) [14]. Marine fungi Eurotium cristatum EN-220 was the source of Cristatumins A, which exhibited inhibitory activity against S. aureus at MIC, 64 μg/mL [15]. Diaporthaceae sp. PSU-SP2/4 gave Diaporthalasin, which displayed significant antibacterial activity against both S. aureus and methicillin-resistant S. aureus (MRSA) with equal MIC values of 2 μg/mL [16]. A xanthone derivative was isolated from A. versicolor MF359 and showed strong activity against S. aureus (MIC, 12.5 μg/mL) [17]. These finding indicate that marine fungi are a promising source for new antibacterial agents. In the present study, marine fungi from Indian marine environments were examined for antibacterial activity against inflammatory acne inducing bacteria C. acnes and S. epidermidis.
Section snippets
Chemicals used
All analytical grade chemicals were purchased from Fischer Scientific (Mumbai, India) and used without further purification. Potato dextrose agar (PDA), potato dextrose broth (PDB), malt extract, mycological peptone, brain heart infusion agar, brain heart infusion broth and Müller-Hinton agar were obtained from HiMedia (Mumbai, India). Streptomycin and penicillin were purchased from Sigma, (Mumbai, India). Diaion HP-20 resin was procured from Mitsubishi Chemical, (Japan).
Collection of samples
Various types of marine
Isolation of marine fungi
In the intertidal zone of the beaches of Goa coastline (28°38′ N x 72°12′ E) and Andaman Island (11.7400′ N x 92.6586′ E) of India, samples of green algae, higher plants (sea grass), soft coral and marine animals were collected. Although this sampling was carried out after the rainy season (in the rainy season very high amount of terrestrial water have been mixed with sea water, which causes mixing of terrestrial and marine organisms), during no moon days and low-tide periods in November to
Discussion
Cutibacterium acnes and S. epidermidis have been recognized as causative agents of acne vulgaris [4]. They stimulate the production of pro-inflammatory cytokines and induce the release of highly toxic reactive oxygen species [33]. The excessive production of these inflammatory mediators results in a destructive phenomenon leading to scarring. Topical antimicrobial agents like tetracycline, benzoyl peroxide, erythromycin, clindamycin, azelaic acid, triclosan, salicylic acid, and various
Conclusion
In conclusion, the aim of this study was to obtain antiacne agents from marine fungal origin. This study demonstrates that methanolic extracts from newly isolated fungal species identified as Simplicillium lamellicola, Leptosphaerulina sp., Penicillium citrinum, Penicillium chrysogenum, and Aspergillus sydowii exhibited potent antimicrobial activity capable of inhibiting the growth of acne inducing microbes. The present study also proposed that the antibacterial effect of the extract may be
Authors' contributions
Conceived and designed the experiments: SA.
Performed the experiments: SA.
Analyzed the data: SA, SD, CB, AA.
Contributed reagents/materials/analysis tools: SA.
Wrote the paper: SA.
All authors read and approved the final manuscript.
Conflicts of interests
The authors declare that they have no conflicts of interest.
Acknowledgements
The authors are thankful to the TERI-Deakin Nano biotechnology Research Centre, India and Deakin University, Australia for providing the necessary infrastructure and financial assistance to carry out this research work. Technical assistance provided by Mr. Chandrakant Tripathi for SEM analysis is highly acknowledged.
References (34)
- et al.
Antimicrobial effects of Thai medicinal plants against acne-inducing bacteria
J. Ethnopharmacol.
(2005) - et al.
Lessons from the past and charting the future of marine natural products drug discovery and chemical biology
Chem. Biol.
(2012) - et al.
Isolation and characterization of Marine fungal metabolites against clinical pathogens
Asian Pac. J. Trop. Dis.
(2012) - et al.
Cristatumins A–D, new indole alkaloids from the marine-derived endophytic fungus Eurotium cristatum EN-220
Bioorg. Med. Chem. Lett.
(2012) - et al.
An antibacterial cytochalasin derivative from the marine-derived fungus Diaporthaceae sp. PSU-SP2/4
Phytochem. Lett.
(2014) - et al.
Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics
PCR Protoc. a guide methods Appl.
(1990) - et al.
Diagnosis and treatment of acne
Am. Fam. Physician
(2004) - et al.
Diagnosis and treatment of acne
Am. Fam. physician
(2012) - et al.
Pathogenesis of acne
Med. Electron Microsc.
(2001) - et al.
Update on pathogenesis and treatment of acne
Curr. Opin. Pediatr.
(2003)