In the present investigation, methanol, chloroform and petroleum ether extracts of the lichen
Toninia candida
(Weber) Th.Fr. were assayed for their antioxidant and antimicrobial activities. The ...phenolic composition of the extracts was determined by HPLC-UV analysis. The predominant phenolic compound in all the extracts was the depsidone norstictic acid. Apart from the norstictic acid, the tested extracts of T. candida contain different amounts and ratios of atranorin and stictic, protocetraric and usnic acids. The lichen extracts showed comparable and strong antioxidant activity, exhibited higher DPPH and hydroxyl radical scavenging capacity, chelating activity and inhibitory activity towards lipid peroxidation. The lichen extracts demonstrated major antimicrobial activity against 8 strains with MIC values ranging from 16.62 to 62.50µg/ml. This is the first report of the chemical composition, antioxidant and antimicrobial activities of the lichen Toninia candida.
Keywords:
Toninia candida, HPLC-UV, chemical composition, antioxidant activity, antimicrobial activity
Acknowledgement:
This work was supported by the Serbian Ministry of Science and the Environment, Project No. 172015
Lichen extracts and metabolites exert a wide variety of biological actions including antibiotic, antiviral, anti-inflammatory, antimycobacterial, analgesic, antiproliferative, antipyretic and ...cytotoxic effects 1. In this work, the lichen species namely
Caloplaca schaereri
(Arnold) Zahlbr,
Teloschistaceae
and
Caloplaca dalmatica
(Massal.) H. Olivier,
Teloschistaceae
were screened for their antioxidant activity using different assay systems 2. Air-dried powdered materials were successively extracted with chloroform, ethyl acetate, acetone and methanol using Soxhlet extractor for 10h each. After extractions of lichens, the main compounds were identified as 1,8-dihydroxy-6-methoxy-3-methyl-9,10-anthraquinone; 1,8-dihydroxy-3-formyl-6-methoxy-9,10-anthraquinone; 1,8-dihydroxy-3-hydroxymethyl-6-methoxy-9,10-anthraquinone; 1,3,8-trihydroxy-9,10-anthraquinone, etc. The content of anthraquinones in
C.schaereri
and
C.dalmatica
were 0.79g/100g and 0.65g/100g dried thallus, respectively. The crude extracts were screened for antioxidant activity. The percentage inhibition of linoleic acid peroxidation was determined by the thiocyanate method, at 37
o
C after addition of different extracts 2. The antioxidant activity of these extracts on the inhibition of peroxidation of linoleic acid were found to be from 24 to 89% compared to BHT. The comparison of scavenging effects of above-mentioned lichen extracts on DPPH radical showed the consistently higher radical-scavenging activity for methanolic extracts. BHT and α-tocopherol were used as positive controls. The results of the reducing powers of different lichen extracts using the potassium ferricyanate method showed that methanol extracts of both lichens had the highest activity. The antioxidant activity of extracts was increased with an increase in concentration. The results suggested that the extracts of lichens
Caloplaca schaereri
and
Caloplaca dalmatica
could be of use as an easily accessible source of natural antioxidants in the pharmacy.
Acknowledgements: Ministry of Science and Environment of Serbia, project N
o
142025.
References: 1. Huneck, S. et al. (1997) Identification of lichen substances. Springer. Berlin.
2. Yen, G.C, et al. (2000) Food Chem. 70: 437–441.
The aim of this work was the analytical characterization of the beta-orcinol depside, baeomycesic acid in lichens extracts. The extract of Thamnolia vermicularis var. subuliformis was analyzed by two ...different methods, namely HPLC–UV and 1H-NMR analysis. The results showed that baeomycesic acid was the most abundant depside in the lichens. These results could be of use for rapid identification of this metabolite in other lichen species. Besides baeomycesic acid, three depsides and one monocyclic phenolic compound were isolated from the lichen extract on the chromatographic column. The structure of baeomycesic acid was confirmed by HPLC–UV and spectroscopic methods. In addition, antioxidant and cytotoxic activities of baeomycesic acid were determined. The result of the testing showed that baeomycesic acid exhibited a moderate radical scavenging activity (IC50 = = 602.10 +/- 0.54 microg/mL) and good cytotoxic activity. This is the first report of detailed analytical characterization and isolation, as well as antioxidant and cytotoxic activities of baeomycesic acid from Thamnolia vermicularis. These results may be helpful in future industrial production of herbal medicines that include this important natural product.
The protection and improvement of environment is one of the most important processes which requires different aspects of management and knowledge, and which has extensive consequences on survival of ...mankind. Today contemporary trends as well as the way of operating and of communicating require a modern manager who will in addition to solving economical problems have to be familiar with the problems of environment as well.
In this study, we were analyzed the physico-chemical parameters of water in the lake Celije (Serbia) and its impact on phytoplankton in summer and winter, in order to determine the water quality in ...the lake. Temperature was ranged from 6 deg C in winter to 26.5 deg C in summer, pH values from 7.71 to 8.10 in winter and from 7.86 to 9.18 in summer. The concentration of ammonia was ranged between 0.03 to 1.20 mg/cubic dm in winter and between 0.18-1.55 mg/cubic dm in summer. Density of phytoplankton in the summer period was growing in line with the values of physico-chemical parameters. Analysis were confirmed that the water of Lake Celije was good quality and in agreement with the limit values of required quality for drinking water.
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