Sonja Duletić-Laušević

Biology of Pleurotus eryngii and role in biotechnological processes : a review

Pleurotus eryngii is considered a complex species owing to a perplexed structure within species and a wide geographical distribution. Due to its remarkable flavor, high nutritional value, and numerous medicinal features, P. eryngii is commercially cultivated on various raw plant materials. Its efficacy in using nutrients from lignocellulose residues is based on possession of a potent ligninolytic enzyme system, constituted of laccase, Mn-oxidizing peroxidases, and aryl-alcohol oxidase, which successfully degrade different aromatic compounds. Similarly, due to the ability of these enzymes, P. eryngii plays a very important role in many biotechnological processes, such as food production (edible basidiomata), biotransformation of raw plant materials to feed, biopulping and biobleaching of paper pulp, as well as bioremediation of soil and industrial waters.Pleurotus eryngii is considered a complex species owing to a perplexed structure within species and a wide geographical distribution. Due to its remarkable flavor, high nutritional value, and numerous medicinal features, P. eryngii is commercially cultivated on various raw plant materials. Its efficacy in using nutrients from lignocellulose residues is based on possession of a potent ligninolytic enzyme system, constituted of laccase, Mn-oxidizing peroxidases, and aryl-alcohol oxidase, which successfully degrade different aromatic compounds. Similarly, due to the ability of these enzymes, P. eryngii plays a very important role in many biotechnological processes, such as food production (edible basidiomata), biotransformation of raw plant materials to feed, biopulping and biobleaching of paper pulp, as well as bioremediation of soil and industrial waters.

Chemical Composition and Antimicrobial Activities of Essential Oils of Myrrhis odorata (L.) Scop, Hypericum perforatum L and Helichrysum arenarium (L.) Moench

Abstract The chemical composition and antimicrobial activities of essential oils isolated from Myrrhis odorata, Hypericum perforatum and Helichrysum arenarium were investigated against seven bacterial and six fungal species. Activity against the bacteria and C. albicans were investigated by a bioautographic test on TLC plates, while all the other fungi were tested by a microdilution test. The oil of H. arenarium showed the best antibacterial activity, while M. odorata oil showed the lowest effect, to compare with commercial products. In contrast, the best antifungal activity was observed for M. odorata oil, while H. arenarium showed the lowest antifungal potential. Minimal inhibitory and fungicidal concentrations for fungi were 0.5–120 μg/mL. The oil of M. odorata showed better activity then commercial product and it can be seen that this oil is very effective against all fungi tested.

Effect of Copper and Manganese Ions on Activities of Laccase and Peroxidases in Three Pleurotus Species Grown on Agricultural Wastes

Copper (Cu2+) and manganese (Mn2+) ions influenced laccase (Lac) and peroxidase production in Pleurotus eryngii, Pleurotus ostreatus, and Pleurotus pulmonarius. In P. eryngii, the optimum Cu2+ concentration for Lac production was 1 mM and for peroxidases 10mM, and Mn2+ concentration of 5mM led to peaks of Lac and peroxidase activity. In P. ostreatus HAI 493, the highest level of Lac activity was at Cu2+ concentrations of 1 and 10 mM and Mn2+ concentration of 1mM, respectively. The absence of Cu2+ and Mn2+ caused the highest levels of peroxidase production. In P. ostreatus HAI 494, the highest level of Lac activity was at a Cu2+ concentration of 5 mM and at Mn2+ concentration of 1 mM, respectively. High levels of peroxidase activity were found in the medium without and with 1mM Cu2+, and at 1 and 5 mM Mn2+, respectively. In P. pulmonarius, the highest Lac activity was found in the presence of 5 mM Cu2+ and 5 mM Mn2+, respectively. The absence of Cu2+ and Mn2+ as well as their presence at a concentration of 1 mM led to the peaks of peroxidase activities.

Micromorphology of trichomes of Thymus malyi (Lamiaceae)

Micromorphological, ultrastructural and morphometric investigations of the trichomes of Thymus malyi were carried out using a light microscope, a scanning electron microscope and a transmission electron microscope. Unbranched non‐glandular trichomes, peltate and capitate glandular trichomes were described. The leaves of Thymus malyi bear non‐glandular and glandular trichomes on both sides. Estimates of the volume density (i.e. their volume fraction per unit volume) of non‐glandular trichomes were higher as compared to volume density of peltate and capitate glandular trichomes. Estimates of the number of these trichomes per area on sections showed that the capitate trichomes were the most abundant. Ultrastructural analyses of cell inner structure have shown numerous mitochondria, big nuclei and plastids with lipid globules and starch grains.

The in vitro antioxidative and cytotoxic effects of selected Salvia species water extracts

The current paper presents antioxidant and cytotoxic activities and total phenolic and flavonoid content of the selected species of genus Salvia (Lamiaceae) growing wild in Macedonia ( S. jurisicii Kosanin, S. amplexicaulis Lam . , S. ringens Sibth. & Sm.) and Libya ( S. fruticosa Mill. and S. lanigera Poir.). Crude water extracts, obtained from aerial parts, were yielded from 6.50 to 14.32%. Total phenolic content was the highest in water extracts of S. amplexicaulis and S. ringens (226.30 and 189.01 mg GAE/g, respectively), while the flavonoids were the most abundant in S. jurisicii extract (32.36 mg QE/g). Antioxidant activities of extracts were measured using DPPH, ABTS and FRAP assays. S. amplexicaulis and S. ringens extracts showed the strongest antioxidant activity, measured using DPPH (14.21 and 23.44 μg/mL, respectively) and ABTS assays (2.91 and 2.42 mg AAE/g, respectively). In FRAP assay, S. amplexicaulis and S. fruticosa extracts exhibited strongest activity (1406.73 and 1191.51 µmol Fe(II)/g). Water extract of S. amplexicaulis and S. ringens performed the strongest cytotoxic activity against K562 cells (151.07 and 173.06 μg/mL, respectively). Based on these findings, it can be concluded that S. amplexicaulis and S. ringens water extracts could be considered as possible source of antioxidant and cytotoxic agents.

Composition and biological activities of different extracts of Salvia jurisicii, a rare and endemic Macedonian species

Abstract This is the first report on the phenolic composition and biological activities of endemic species Salvia jurisicii Košanin (Lamiaceae) originating from Macedonia. Aerial parts of S. jurisicii were extracted with dichloromethane, ethyl acetate, methanol, ethanol and water. All extracts were tested spectrophotometrically for total phenolic and flavonoid contents, while their phenolic composition was analyzed using HPLC-DAD. The antioxidant activity of extracts was studied using 2,2-dyphenyl-1-picrylhydrazyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), ferric reducing ability of plasma and ß-carotene bleaching assays. Being the most frequently used solvents for extraction of bioactive ingredients from medicinal plants, water and ethanol extracts were chosen for further testing of antimicrobial, cytotoxic and antineurodegenerative activities. More polar solvent extracts showed higher total phenolic content and lower flavonoid content. Ethanol and methanol extracts, followed by water extract exhibited the strongest antioxidant activity. Extracts showed antimicrobial activity against certain bacteria and micromycetes. The cytotoxicity assay showed slight toxicity to HCT-116 cell line. In the antineurodegenerative assays, the extracts performed lower inhibition of acetylcholinesterase and tyrosinase than standards. According to the results of this study, it can be inferred that more polar extracts of S. jurisicii were quantitatively richer in total phenolics, showing stronger antioxidant activity. Ethanol extract showed stronger biological activities comparing to water extract.

Chemical profiling and assessment of antineurodegenerative and antioxidant properties of Veronica teucrium L. and Veronica jacquinii Baumg

Neuroprotective potential of V. teucrium and V. jacquinii methanol extracts was analyzed. Chemical analysis of investigated extracts showed the presence of phenolic acid derivatives, flavonoids and one secoiridoid. The detected flavonoids derived from flavones (luteolin and isoscutellarein in V. jacquinii; apigenin, isoscutellarein and luteolin in V. teucrium) and flavonol (quercetin in V. jacquinii). Acteoside was the dominant compound in V. jacquinii, while plantamajoside and isoscutellarein 7‐O‐(6‴‐O‐acetyl)‐β‐allosyl (1‴→2‴)‐β‐glucoside were the major phenolics in V. teucrium. Additionally, the antineurodegenerative activity was tested at concentrations of 25, 50, and 100 μg/ml using acetylcholinesterase (AChE) and tyrosinase (TYR) assays. The inhibition of both enzymes was achieved with the investigated extracts, ranging from 22.78 to 35.40% for AChE and from 9.57 to 16.38% for TYR. There was no statistical difference between the activities of the analyzed extracts. Our data indicate that V. teucrium and V. jacquinii may have beneficial effects against Alzheimers and Parkinsons disease.

Antineurodegenerative, antioxidant and antibacterial activities and phenolic components of Origanum majorana L. (Lamiaceae) extracts of different origin

The aim of this study was to examine chemical composition, as well as antineurodegenerative, antioxidant and antibacterial activity of aqueous and ethanolic extracts of Origanum majorana L. (Lamiaceae) originating from Serbia, Greece, Egypt and Libya. Total phenolics and flavonoids, antioxidant activities, and acetylcholinesterase and tyrosinase inhibitory activities were measured spectrophotometrically. Determination of phenolic compounds in extracts was done using HPLC-DAD technique. Antibacterial activity included determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using the microdilution method. The highest phenolic and flavonoid contents were recorded in the ethanolic extract of the Egyptian sample and in aqueous extract of Serbian sample. The HPLC analysis showed high content of rosmarinic acid, with the highest amount found in the ethanolic extract of the plants from Egypt. Water extracts showed prevalently better antioxidant and antineurodegenerative activity in applied tests than the ethanolic extracts. Gram-positive bacterial strains showed higher sensitivity to tested extracts. According to the obtained results, sweet marjoram samples from Serbia and Egypt can be marked as more promising, due to the highest content of total phenolics and flavonoids and the best antioxidant, antibacterial and tyrosinase inhibitory activity.

Neuroprotective Potential and Chemical Profile of Alternatively Cultivated Ganoderma lucidum Basidiocarps

Various neurodegenerative diseases are the main challenges to the modern medicine and there is a great need for novel, natural, neuroprotective agents. Ganoderma lucidum is a well‐known medicinal mushroom, which health benefits have been confirmed by numerous studies. As demand for its basidiocarps is increased and traditional cultivation on hardwoods is not environmentally friendly and economically justified, finding of alternative substrates is necessary. The aim of the study was to assess the effect of alternative cultivation substrates on the chemical profile of G. lucidum basidiocarps and their capacity to inhibit acetylcholinesterase and tyrosinase, which higher activity is directly associated with neurodegenerative processes. Extracts of basidiocarps cultivated on alternative substrates, especially on clear wheat straw, showed significantly higher inhibition capacities than extracts of commercially‐grown ones. These extracts were considerably different chemically from commercial basidiocarps extracts and even nine new compounds were isolated from them. Our results suggest that cultivation substrate greatly affect the chemical profile and neuroprotective capacity of obtained basidiocarps and wheat straw is a promising cultivation substrate.

Polyphenolic Content and Biological Activities of Post-Distillation Waste of Three Sage Species from the Republic of Macedonia

This research was aimed at investigating polyphenolic content, antioxidant and anti-neurodegenerative activities of post-distillation waste extracts of Macedonian Salvia amplexicaulis, S. jurisicii and S. ringens, for the first time. Total phenolic and flavonoid contents varied in a broad range (3.92-146.49 mg GAE/g and 7.11-67.51 mg QE/g, respectively), with the highest values obtained for S. amplexicaulis and S. ringens extracts. Certain S. amplexicaulis and S. ringens extracts neutralized more than 80% of DPPH radicals at the highest concentration, while S. amplexicaulis extracts showed up to ≈50% inhibition of β-carotene oxidation in β-carotene/linoleic acid assay. Post-distillation waste extracts inhibited acetylcholinesterase (25.94-38.15%) and tyrosinase (18.84-59.52%), with the strongest inhibition of S. amplexicaulis extracts. The obtained results suggest that post-distillation waste of tested species, especially of S. amplexicaulis, show antioxidant and anti-neurodegenerative activities and could be considered as potential raw material rich in polyphenols.