Effect of cultivation conditions on ligninolytic enzyme production by Ganoderma carnosum

Ganoderma carnosum has been found in Europe only, at coniferous trees and it is difficult to distinguish it morphologically from G. lucidum. Since G. carnosum has not been studied biochemically yet, the aim of this study was to analyse its ability to produce Mn-dependent peroxidase (MnP), versatile peroxidase (VP) and laccase (Lac) under conditions of solid-state fermentation of selected plant raw materials as carbon sources, in the presence of different nitrogen concentrations in the medium. Wheat straw, corn stem, oak and grapevine sawdust were the analysed plant raw materials. Nitrogen source in synthetic medium was NH4NO3 and its concentrations were: 10mM N and 20 mM N. Enzyme activity was determined spectrophotometrically, using ABTS and phenol red, as the substrates for Lac and Mn-oxidizing peroxidases, respectively. Maximum level of MnP activity (56.82 U/l) was obtained in the medium with wheat straw and nitrogen concentration of 10 mM. Best carbon source for VP production was grapevine sawdust at nitrogen concentration of 10 mM (80.80 U/l). The obtained Lac activity was very low in the medium with wheat straw (1.80 U/l), while it was not detected in the presence of other three analyzed plant raw materials. Maximum of total protein content (0.06 mgml-1) was noted in the medium where oak sawdust was carbon source and nitrogen concentration was 20 mM.Vrste roda Ganoderma su producenti mnogih biološki aktivnih supstanci pa su objekti proučavanja mnogih medicinskih i farmaceutskih studija. U novije vreme se sve više pažnje poklanja upoznavanju njihovog ligninolitičkog enzimskog sistema, u cilju uspešne primene u različitim biotehnološkim procesima. Za razliku od G. lucidum, čiji je ligninolitički sistem intenzivno proučavan, ostale vrste ovog roda su retko bile objekti istraživanja. G. carnosum se teško morfološki razlikuje od G. lucidum. i još uvek nije biohemijski proučena, pa je cilj našeg istraživanja bio analiza produkcije Mn-oksidujućih peroksidaza i lakaza u uslovima čvrste kultivacije, na različitim biljnim ostacima (pšenična slama, stabljike kukuruza, piljevina hrasta i vinove loze) u prisustvu azota u obliku NH4NO3 i u koncentracijama od 10 mM, odnosno 20 mM. Maksimum produkcije Mn-zavisne peroksidaze dobijen je na pšeničnoj slami pri koncentraciji azota od 10 mM (56.82 U/l). Piljevina vinove loze i koncentracija azota od 10 mM bili su optimalni za sintezu verzatil peroksidaze (80.80 U/l). Dobijena aktivnost lakaza je bila izuzetno niska u medijumu sa pšeničnom slamom (1.80 U/l), dok na ostalim biljnim ostacima nije zabeležena. Maksimalni sadržaj ukupnih proteina je bio najveći u medijumu sa piljevinom hrasta kao izvorom ugljenika i koncentracijom azota od 10 mM.Projekat ministarstva br. 14304

Effect of cultivation conditions on ligninolytic enzyme production by Ganoderma carnosum

Ganoderma carnosum has been found in Europe only, at coniferous trees and it is difficult to distinguish it morphologically from G. lucidum. Since G. carnosum has not been studied biochemically yet, the aim of this study was to analyse its ability to produce Mn-dependent peroxidase (MnP), versatile peroxidase (VP) and laccase (Lac) under conditions of solid-state fermentation of selected plant raw materials as carbon sources, in the presence of different nitrogen concentrations in the medium. Wheat straw, corn stem, oak and grapevine sawdust were the analysed plant raw materials. Nitrogen source in synthetic medium was NH4NO3 and its concentrations were: 10mM N and 20 mM N. Enzyme activity was determined spectrophotometrically, using ABTS and phenol red, as the substrates for Lac and Mn-oxidizing peroxidases, respectively. Maximum level of MnP activity (56.82 U/l) was obtained in the medium with wheat straw and nitrogen concentration of 10 mM. Best carbon source for VP production was grapevine sawdust at nitrogen concentration of 10 mM (80.80 U/l). The obtained Lac activity was very low in the medium with wheat straw (1.80 U/l), while it was not detected in the presence of other three analyzed plant raw materials. Maximum of total protein content (0.06 mgml-1) was noted in the medium where oak sawdust was carbon source and nitrogen concentration was 20 mM.Vrste roda Ganoderma su producenti mnogih biološki aktivnih supstanci pa su objekti proučavanja mnogih medicinskih i farmaceutskih studija. U novije vreme se sve više pažnje poklanja upoznavanju njihovog ligninolitičkog enzimskog sistema, u cilju uspešne primene u različitim biotehnološkim procesima. Za razliku od G. lucidum, čiji je ligninolitički sistem intenzivno proučavan, ostale vrste ovog roda su retko bile objekti istraživanja. G. carnosum se teško morfološki razlikuje od G. lucidum. i još uvek nije biohemijski proučena, pa je cilj našeg istraživanja bio analiza produkcije Mn-oksidujućih peroksidaza i lakaza u uslovima čvrste kultivacije, na različitim biljnim ostacima (pšenična slama, stabljike kukuruza, piljevina hrasta i vinove loze) u prisustvu azota u obliku NH4NO3 i u koncentracijama od 10 mM, odnosno 20 mM. Maksimum produkcije Mn-zavisne peroksidaze dobijen je na pšeničnoj slami pri koncentraciji azota od 10 mM (56.82 U/l). Piljevina vinove loze i koncentracija azota od 10 mM bili su optimalni za sintezu verzatil peroksidaze (80.80 U/l). Dobijena aktivnost lakaza je bila izuzetno niska u medijumu sa pšeničnom slamom (1.80 U/l), dok na ostalim biljnim ostacima nije zabeležena. Maksimalni sadržaj ukupnih proteina je bio najveći u medijumu sa piljevinom hrasta kao izvorom ugljenika i koncentracijom azota od 10 mM.Projekat ministarstva br. 14304

Investigation on antibacterial synergism of Origanum vulgare and Thymus vulgaris essential oils

Essential oils are well known as strong antimicrobial agents of plant origin. In spite of this, the antimicrobial synergism of essential oils isolated from different plant species is poorly investigated. The following study examines the synergism of the essential oils of Origanum vulgare L. and Thymus vulgaris L against pathogenic bacteria, Staphylococcus aureus and Salmonella typhimurium. First, the antibacterial effect of the oils was tested, and the minimal inhibitory concentrations (MIC) of both oils were determined using the microdilution method. To test whether the oils act synergistically, every possible combination of essential oil concentrations was used in a dynamic checkerboard method. The results indicated that the oils indeed acted synergistically with fractional inhibitory concentration indexes of 0.45 and 0.50. [Projekat Ministarstva nauke Republike Srbije, br. 173032

Investigation on antibacterial synergism of Origanum vulgare and Thymus vulgaris essential oils

Essential oils are well known as strong antimicrobial agents of plant origin. In spite of this, the antimicrobial synergism of essential oils isolated from different plant species is poorly investigated. The following study examines the synergism of the essential oils of Origanum vulgare L. and Thymus vulgaris L against pathogenic bacteria, Staphylococcus aureus and Salmonella typhimurium. First, the antibacterial effect of the oils was tested, and the minimal inhibitory concentrations (MIC) of both oils were determined using the microdilution method. To test whether the oils act synergistically, every possible combination of essential oil concentrations was used in a dynamic checkerboard method. The results indicated that the oils indeed acted synergistically with fractional inhibitory concentration indexes of 0.45 and 0.50.Projekat ministarstva br. 17303

Chemical analysis and antimicrobial activities of the essential oils of Satureja thymbra L. and Thymbra spicata L. and their main components

This work covers the chemical composition and antimicrobial activities of the essential oils isolated from Satureja thymbra and Thymbra spicata analyzed using GC/MS. The main components of S. thymbra oil were thymol (33.8 %), γ-terpinene (30.8 %) and p-cymene (11.8 %). The main components in T. spicata oil were carvacrol (74.5 %) and γ-terpinene (11.2 %). The oils and their main components, thymol and carvacrol, were assayed by applying the microdilution method for antibacterial and antifungal activity against food poisoning, plant, animal and human pathogenic microorganisms. The oil of T. spicata and carvacrol showed the highest antimicrobial activity.Projekat ministarstva br. 17303

Antimicrobial activity of aqueous extract of Laetiporus sulphureus (Bull.: Fr.) Murill

Wood-rotting basidiomycete, Laetiporus sulphureus (Bull.: Fr.) Murill., also known as chicken of the woods, is known for its nutritional value. In this study, aqueous extract obtained from L. sulphureus was investigated for its antimicrobial properties using microdilution in vitro assay. Plant, animal and human pathogens, as well as food spoilage agents, were tested. Aqueous extract obtained from L. sulphureus showed strong activity against the tested microorganisms in a dose dependent manner. Considering that there is a constant emerging of pathogen resistance to the known synthetic agents, there is an undeniable need for new therapeutical drugs and preservatives in food industry. Thus, these results that indicate activity of natural products may be of practical use.Gljiva mrke truleži, Laetiporus sulphureus (Bull.: Fr) Murill., poznata i kao šumsko pile, već je poznata po svojoj nutritivnoj vrednosti. U ovoj studiji ispitivana je antimikrobna sposobnost vodenog ekstrakta L. sulphureus, mikrodilucionom in vitro metodom. Biljni, životinjski i humani patogeni, kao i prouzrokovači kvarenja hrane su testirani. Vodeni ekstrakt dobijen od L. sulphureus pokazao je snažnu aktivnost na testirane mikroorganizme uz doznu zavisnost. S obzirom da postoji konstantni porast rezistentnosti patogena na poznate sintetičke agense, potreba za novim terapeutskim lekovima i konzervansima u prehrambenoj industriji je neophodnost. Stoga, rezultati koji ukazuju na aktivnost prirodnih produkata mogu biti od velikog praktičnog značaja.Projekat ministarstva br. 14304

Control of Penicillium Verrucosum var. cyclopium in cream cheese by Agaricus bohusii extract

Food processors, food safety researchers, and regulatory agencies have bean increasingly concerned with the growing number of food-borne illness outbreaks caused by different fungal pathogens. Mushrooms could be a potentially useful sources of antimicrobial compounds. Agaricus bohusii is edible, taste and prized mushroom from Agraicaceae family. We tested ethanol extract of this mushroom as a natural food preservative. Extract was added in cream cheese infected with food contaminating microfungi P. verucosum var. eye/opium (previously isolated from cheese) in different concentration (10-100 mg/ml). Solutions were kept at room temperature and -at +4°C and dally observed during 7 days. Growth inhibition of P. verucosum var. eye/opium by ethanol extract of A. bohusli is calculated as a percent of inhibition. There Is no growth of microfungi at second day after the incubation at the samples kept at +4°C, samples at 25°C showed different growth Inhibition depending on extract concentration. Growth inhibition percentage of extract toward microfungal at 4th day can be presented as following: 13.3-53.3 % at +4"C and 100 % on all concentration at room temperature. The growth inhibition of microfungi was also observed at 7th day but on higher level. 83.3-90.0% In refrigerator, while dose depending factor was not observed at the samples kept at room temperature. On all concentration tested the growth Inhibition was 100 %. It looks that the lowest concentration (10 mg) of mushroom extract was either strongly effective as the highest one (100 mg) at room temperature. Because of increasing pressure of consumers and legal authorities, the food industry has tended to reduce the use of chemical preservatives in their products to either completely nil or to adopt more natural alternatives for the maintenance or extension of product shelf life. In this manner mushroom extracts may replace conventional chemical antimicrobials

Characteristics of local pulmonary response following intranasal application of Aspergillus fumigatus conidia

In this study, histopathology of local pulmonary response following intranasal inoculation of different doses of Aspergillus fumigatus conidia in laboratory rats was evaluated. Development of response was evaluated on days seven and twenty one, following conidia inoculation by cell infiltration and by presence of A. fumigatus conidia in homogenates of lung tissue. Total and differential peripheral blood leukocyte counts and state of leukocyte adhesion/aggregation were monitored to estimate the presence of systemic response in infected individuals. Mycological examination revealed the presence of conidia in lung tissue homogenates of infected animals, with high number of non-germinating spores on day twenty one, following the inoculation of lower conidia dose. Histopathological examination revealed the presence of lymphocytes perivascularly and in vascular lumen in the lungs. Presented data demonstrate pulmonary immune response following A. fumigatus conidia administration