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Fulltext Bioactivities of Lyngbyabellins from Cyanobacteria of Moorea and Okeania Genera

Fathoni I, Petitbois JG, Alarif WM, Abdel-Lateff A, Al-Lihaibi SS, Yoshimura E, et al.

Molecules, 2020 Sep 01;25(17).
PMID: 32882989 DOI: 10.3390/molecules25173986

Cyanobacteria are reported as rich sources of secondary metabolites that provide biological activities such as enzyme inhibition and cytotoxicity. Ten depsipeptide derivatives (lyngbyabellins) were isolated from a Malaysian Moorea bouillonii and a Red Sea Okeania sp.: lyngbyabellins G (1), O (2), P (3), H (4), A (7), 27-deoxylyngbyabellin A (5), and homohydroxydolabellin (6). This study indicated that lyngbyabellins displayed cytotoxicity, antimalarial, and antifouling activities. The isolated compounds were tested for cytotoxic effect against human breast cancer cells (MCF7), for antifouling activity against Amphibalanus amphitrite barnacle larvae, and for antiplasmodial effect towards Plasmodium falciparum. Lyngbyabellins A and G displayed potent antiplasmodial effect against Plasmodium, whereas homohydroxydolabellin showed moderate effect. For antifouling activity, the side chain decreases the activity slightly, but the essential feature is the acyclic structure. As previously reported, the acyclic lyngbyabellins are less cytotoxic than the corresponding cyclic ones, and the side chain increases cytotoxicity. This study revealed that lyngbyabellins, despite being cytotoxic agents as previously reported, also exhibit antimalarial and antifouling activities. The unique chemical structures and functionalities of lyngbyabellin play an essential role in their biological activities.

Matched MeSH terms: Depsipeptides/isolation & purification; Depsipeptides/pharmacology*; Depsipeptides/chemistry
Fulltext In vitro activity of teicoplanin, vancomycin, A16686, clindamycin, erythromycin and fusidic acid against anaerobic bacteria

Hassan H, O'Hare MD, Felmingham D

Singapore Med J, 1990 Feb;31(1):56-8.
PMID: 2139737

The in vitro activity of teicoplanin and A16686, two new glycopeptide antibiotics was determined against 196 isolates of anaerobic bacteria. The activity of teicoplanin and A16686, in comparison with that of vancomycin, clindamycin, erythromycin and fusidic acid was 2 to 16 times higher against the gram positive anaerobes, namely, Propionibacterium acnes, Clostridium perfringens, Clostridium difficile, Clostridium species, Peptococcus species and Peptostreptococcus species. However, Bacteroides fragilis was resistant to teicoplanin and A16686 while Bacteroides melaninogenicus and Bacteroides bivius were found to be sensitive.

Matched MeSH terms: Depsipeptides*
Production of major mycotoxins by Fusarium species isolated from wild grasses in Peninsular Malaysia

Nor Azliza I, Hafizi R, Nurhazrati M, Salleh B

Sains Malaysiana, 2014;43:89-94.

The Fusarium species are notoriously known for causing various plants and animal diseases and producing a number of harmful mycotoxins. The mycotoxins production by species recovered from non-agricultural hosts such as wild grasses have hitherto never been given attention. We examined 30 strains representing 12 Fusarium species i.e. F. oxysporum, F. solani, F. semitectum, F. nelsonii, F. compactum, F. equiseti, F. chlamydosporum, F. proliferatum, F. subglutinans, F. sacchari, F. lateritium and F. incarnatum-equiseti species complex isolated from wild grasses in Peninsular Malaysia for the production of four major mycotoxins i.e. moniliformin (MON), fumonisin BI (FB1), zearalenone (ZEN) and beauvericin (BEA) using TLC and HPLC techniques. BEA was the highest frequency of mycotoxin detected, followed by MON, ZEN and FB1. This study also presented the first report of BEA production by F. solani, F. compactum and F. chlamydosporum. All mycotoxins were not produced by F. nelsonii and F. lateritium. All Fusarium species were isolated from asymptomatic grasses, hence they are likely to exist as endophytes or latent pathogens.

Matched MeSH terms: Depsipeptides
The inhibitory effects of aureobasidin A on Candida planktonic and biofilm cells

Tan HW, Tay ST

Mycoses, 2013 Mar;56(2):150-6.
PMID: 22882276 DOI: 10.1111/j.1439-0507.2012.02225.x

Aureobasidin A (AbA) is a cyclic depsipeptide antifungal compound that inhibits a wide range of pathogenic fungi. In this study, the in vitro susceptibility of 92 clinical isolates of various Candida species against AbA was assessed by determining the planktonic and biofilm MICs of the isolates. The MIC(50) and MIC(90) of the planktonic Candida yeast were 1 and 1 μg ml(-1), respectively, whereas the biofilm MIC(50) and MIC(90) of the isolates were 8 and ≥64 μg ml(-1) respectively. This study demonstrates AbA inhibition on filamentation and biofilm development of C. albicans. The production of short hyphae and a lack of filamentation might have impaired biofilm development of AbA-treated cells. The AbA resistance of mature Candidia biofilms (24 h adherent population) was demonstrated in this study.

Matched MeSH terms: Depsipeptides/pharmacology*
A study on Candida biofilm growth characteristics and its susceptibility to aureobasidin A

Munusamy K, Vadivelu J, Tay ST

Rev Iberoam Micol, 2018 03 12;35(2):68-72.
PMID: 29544734 DOI: 10.1016/j.riam.2017.07.001

BACKGROUND: Biofilm is known to contribute to the antifungal resistance of Candida yeasts. Aureobasidin A (AbA), a cyclic depsipeptide targeting fungal sphingolipid biosynthesis, has been shown to be effective against several Candida species.
AIMS: The aim of this study was to investigate Candida biofilm growth morphology, its biomass, metabolic activity, and to determine the effects of AbA on the biofilm growth.
METHODS: The biofilm forming ability of several clinical isolates of different Candida species from our culture collection was determined using established methods (crystal violet and XTT assays). The determination of AbA planktonic and biofilm MICs was performed based on a micro-broth dilution method. The anti-biofilm effect of AbA on Candida albicans was examined using field emission scanning electron microscope (FESEM) analysis.
RESULTS: A total of 35 (29.7%) of 118 Candida isolates were regarded as biofilm producers in this study. Candida parapsilosis was the largest producer, followed by Candida tropicalis and C. albicans. Two morphological variants of biofilms were identified in our isolates, with 48.6% of the isolates showing mainly yeast and pseudohyphae-like structures, while the remaining ones were predominantly filamentous forms. The biofilm producers were divided into two populations (low and high), based on the ability in producing biomass and their metabolic activity. Candida isolates with filamentous growth, higher biomass and metabolic activity showed lower AbA MIC50 (at least fourfold), compared to those exhibiting yeast morphology, and lower biomass and metabolic activity. The observation of filament detachment and the almost complete removal of biofilm from AbA-treated C. albicans biofilm in FESEM analysis suggests an anti-biofilm effect of AbA.
CONCLUSIONS: The variability in the growth characteristics of Candida biofilm cultures affects susceptibility to AbA, with higher susceptibility noted in biofilm cultures exhibiting filamentous form and high biomass/metabolic activity.

Matched MeSH terms: Depsipeptides/pharmacology*
Fulltext Potential role of marine species-derived bioactive agents in the management of SARS-CoV-2 infection

Asif M, Saleem M, Yaseen HS, Yehya AH, Saadullah M, Zubair HM, et al.

Future Microbiol, 2021 Nov;16(16):1289-1301.
PMID: 34689597 DOI: 10.2217/fmb-2021-0024

COVID-19, caused by the SARS-CoV-2 outbreak, has resulted in a massive global health crisis. Bioactive molecules extracted or synthesized using starting material obtained from marine species, including griffithsin, plitidepsin and fingolimod are in clinical trials to evaluate their anti-SARS-CoV-2 and anti-HIV efficacies. The current review highlights the anti-SARS-CoV-2 potential of marine-derived phytochemicals explored using in silico, in vitro and in vivo models. The current literature suggests that these molecules have the potential to bind with various key drug targets of SARS-CoV-2. In addition, many of these agents have anti-inflammatory and immunomodulatory potentials and thus could play a role in the attenuation of COVID-19 complications. Overall, these agents may play a role in the management of COVID-19, but further preclinical and clinical studies are still required to establish their role in the mitigation of the current viral pandemic.

Matched MeSH terms: Depsipeptides