14 research outputs found

    Correction Factors for Direct Gas Chromatographic Determination of Acrylic Acid in Aqueous Solutions Using Polyethylene Glycol Adipate as Stationary Phase

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    The problem of »repeated peaks« associted with the direct gas chromatographic determinations of aqueous acrylic acid solutions with the concentration range of 0.05 – 10.00 g dm–3 has been discussed for the case of polyethylene glycol adipate as a stationary phase. Based on more than 700 injections of standard solutions on the packed column, a set of correction factors has been proposed. Simple relations between the »repeated peaks« heights and the reference solution concentrations were found. The reproducibility of the method was evaluated

    Correction Factors for Direct Gas Chromatographic Determination of Acrylic Acid in Aqueous Solutions Using Polyethylene Glycol Adipate as Stationary Phase

    Get PDF
    The problem of »repeated peaks« associted with the direct gas chromatographic determinations of aqueous acrylic acid solutions with the concentration range of 0.05 – 10.00 g dm–3 has been discussed for the case of polyethylene glycol adipate as a stationary phase. Based on more than 700 injections of standard solutions on the packed column, a set of correction factors has been proposed. Simple relations between the »repeated peaks« heights and the reference solution concentrations were found. The reproducibility of the method was evaluated

    Biotehnološka primjena gljive Lentinula edodes – od lentinana do lektina

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    Lentinula edodes was the first medicinal macrofungus to enter the realm of modern biotechnology. The present paper briefly reviews the history of the modern biotechnology of this mushroom starting with the production of the polysaccharide preparation lentinan, and ending with an overview of our own work regarding the production of lectins. Our work with lectins has involved studies of the effect of initial pH, carbon and nitrogen sources and the C:N ratio on lectin production in both the mycelium and culture medium. We have shown that lectin activity is related to morphological development, with the activity being highest in extracts of the pigmented mycelial films that precede fruiting body production.Lentinula edodes prva je medicinska gljiva koja se počela primjenjivati u suvremenoj biotehnologiji. U ovom se radu nalazi kratak pregled razvoja suvremene biotehnološke primjene te gljive, počevši od proizvodnje polisaharida lentinana pa sve do prikaza rezultata autora u proizvodnji lektina. Njihovo istraživanje obuhvaća ispitivanje učinka početne pH-vrijednosti, izvora ugljika i dušika te njihova omjera na nastanak lektina u podlozi za uzgoj micelija i kulture. Dokazano je da je aktivnost lektina povezana s morfološkim razvojem, te da je najveća u ekstraktima pigmentiranoga micelijskog filma koji prethodi nastanku plodišta

    Biotehnološka primjena gljive Lentinula edodes – od lentinana do lektina

    Get PDF
    Lentinula edodes was the first medicinal macrofungus to enter the realm of modern biotechnology. The present paper briefly reviews the history of the modern biotechnology of this mushroom starting with the production of the polysaccharide preparation lentinan, and ending with an overview of our own work regarding the production of lectins. Our work with lectins has involved studies of the effect of initial pH, carbon and nitrogen sources and the C:N ratio on lectin production in both the mycelium and culture medium. We have shown that lectin activity is related to morphological development, with the activity being highest in extracts of the pigmented mycelial films that precede fruiting body production.Lentinula edodes prva je medicinska gljiva koja se počela primjenjivati u suvremenoj biotehnologiji. U ovom se radu nalazi kratak pregled razvoja suvremene biotehnološke primjene te gljive, počevši od proizvodnje polisaharida lentinana pa sve do prikaza rezultata autora u proizvodnji lektina. Njihovo istraživanje obuhvaća ispitivanje učinka početne pH-vrijednosti, izvora ugljika i dušika te njihova omjera na nastanak lektina u podlozi za uzgoj micelija i kulture. Dokazano je da je aktivnost lektina povezana s morfološkim razvojem, te da je najveća u ekstraktima pigmentiranoga micelijskog filma koji prethodi nastanku plodišta

    Effect of Media Components on the Mycelial Film Formation in Submerged Culture of Lentinus edodes (Shiitake)

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    A relationship between the chemical composition of nutrient medium, the activity of extracellular lectins of Lentinus edodes (Berk.) Sing Lentinula edodes (Berk.) Pegler (shiitake), and the formation of pigmented mycelial film in liquid culture has been found. A possibility to regulate the lectin activity of shiitake using the synthetic components has been shown. The formulation of medium, on which the brown mycelial film appears in several days of submerged cultivation, has been proposed. Among the natural amino acids studied as nitrogen sources, and nine divalent metal cations as inorganic additives, L-asparagine and Ca2+ (Mn2+) in the simultaneous presence exhibited the explicit positive effect in respect to the above without regard to the age of the culture. Quantum chemical methods and QSAR were applied to test our supposition that a differential character of interaction between the studied amino acids and Ca2+ (Mn2+) cations should be related not to the distinct electron structures of zwitter ions, but most likely to their differing hydrophobicities. The results obtained seem to make some contribution to the present notion of biochemicalprocesses that give rise to the occurrence of the aforesaid morphological structure of shiitake

    Mushroom-Derived Novel Selenium Nanocomposites’ Effects on Potato Plant Growth and Tuber Germination

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    Multicomponent materials, where nanosized selenium (Se) is dispersed in polymer matrices, present as polymer nanocomposites (NCs), namely, selenium polymer nanocomposites (SeNCs). Selenium as an inorganic nanofiller in NCs has been extensively studied for its biological activity. More ecologically safe and beneficial approaches to obtain Se-based products are the current challenge. Biopolymers have attained great attention with perspective multifunctional and high-performance NCs exhibiting low environmental impact with unique properties, being abundantly available, renewable, and eco-friendly. Composites based on polysaccharides, including beta-glucans from edible and medicinal mushrooms, are bioactive, biocompatible, biodegradable, and have exhibited innovative potential. We synthesized SeNCs on the basis of the extracellular polysaccharides of several medicinal mushrooms. The influence of bio-composites from mushrooms on potato plant growth and tuber germination were studied in two potato cultivars: Lukyanovsky and Lugovskoi. Bio-composites based on Grifola umbellata demonstrated the strongest positive effect on the number of leaves and plant height in both cultivars, without negative effect on biomass of the vegetative part. Treatment of the potato tubers with SeNC from Gr. umbellata also significantly increased germ length. Potato plants exposed to Se-bio-composite from Ganoderma lucidum SIE1303 experienced an increase in the potato vegetative biomass by up to 55% versus the control. We found earlier that this bio-composite was the most efficient against biofilm formation by the potato ring rot causative agent Clavibacter sepedonicus (Cms). Bio-composites based on Pleurotus ostreatus promoted increase in the potato root biomass in the Lugovskoi cultivar by up to 79% versus the control. The phytostimulating ability of mushroom-based Se-containing bio-composites, together with their anti-phytopathogenic activity, testifies in favor of the bifunctional mode of action of these Se-biopreparations. The application of stimulatory green SeNCs for growth enhancement could be used to increase crop yield. Thus, by combining myco-nanotechnology with the intrinsic biological activity of selenium, an unexpectedly efficient tool for possible applications of SeNCs could be identified

    Mushroom-Derived Novel Selenium Nanocomposites’ Effects on Potato Plant Growth and Tuber Germination

    No full text
    Multicomponent materials, where nanosized selenium (Se) is dispersed in polymer matrices, present as polymer nanocomposites (NCs), namely, selenium polymer nanocomposites (SeNCs). Selenium as an inorganic nanofiller in NCs has been extensively studied for its biological activity. More ecologically safe and beneficial approaches to obtain Se-based products are the current challenge. Biopolymers have attained great attention with perspective multifunctional and high-performance NCs exhibiting low environmental impact with unique properties, being abundantly available, renewable, and eco-friendly. Composites based on polysaccharides, including beta-glucans from edible and medicinal mushrooms, are bioactive, biocompatible, biodegradable, and have exhibited innovative potential. We synthesized SeNCs on the basis of the extracellular polysaccharides of several medicinal mushrooms. The influence of bio-composites from mushrooms on potato plant growth and tuber germination were studied in two potato cultivars: Lukyanovsky and Lugovskoi. Bio-composites based on Grifola umbellata demonstrated the strongest positive effect on the number of leaves and plant height in both cultivars, without negative effect on biomass of the vegetative part. Treatment of the potato tubers with SeNC from Gr. umbellata also significantly increased germ length. Potato plants exposed to Se-bio-composite from Ganoderma lucidum SIE1303 experienced an increase in the potato vegetative biomass by up to 55% versus the control. We found earlier that this bio-composite was the most efficient against biofilm formation by the potato ring rot causative agent Clavibacter sepedonicus (Cms). Bio-composites based on Pleurotus ostreatus promoted increase in the potato root biomass in the Lugovskoi cultivar by up to 79% versus the control. The phytostimulating ability of mushroom-based Se-containing bio-composites, together with their anti-phytopathogenic activity, testifies in favor of the bifunctional mode of action of these Se-biopreparations. The application of stimulatory green SeNCs for growth enhancement could be used to increase crop yield. Thus, by combining myco-nanotechnology with the intrinsic biological activity of selenium, an unexpectedly efficient tool for possible applications of SeNCs could be identified

    Coumarins as Fungal Metabolites with Potential Medicinal Properties

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    Coumarins are a structurally varied set of 2H-chromen-2-one compounds categorized also as members of the benzopyrone group of secondary metabolites. Coumarin derivatives attract interest owing to their wide practical application and the unique reactivity of fused benzene and pyrone ring systems in molecular structure. Coumarins have their own specific fingerprints as antiviral, antimicrobial, antioxidant, anti-inflammatory, antiadipogenic, cytotoxic, apoptosis, antitumor, antitubercular, and cytotoxicity agents. Natural products have played an essential role in filling the pharmaceutical pipeline for thousands of years. Biological effects of natural coumarins have laid the basis of low-toxic and highly effective drugs. Presently, more than 1300 coumarins have been identified in plants, bacteria, and fungi. Fungi as cultivated microbes have provided many of the nature-inspired syntheses of chemically diverse drugs. Endophytic fungi bioactivities attract interest, with applications in fields as diverse as cancer and neuronal injury or degeneration, microbial and parasitic infections, and others. Fungal mycelia produce several classes of bioactive molecules, including a wide group of coumarins. Of promise are further studies of conditions and products of the natural and synthetic coumarins’ biotransformation by the fungal cultures, aimed at solving the urgent problem of searching for materials for biomedical engineering. The present review evaluates the fungal coumarins, their structure-related peculiarities, and their future therapeutic potential. Special emphasis has been placed on the coumarins successfully bioprospected from fungi, whereas an industry demand for the same coumarins earlier found in plants has faced hurdles. Considerable attention has also been paid to some aspects of the molecular mechanisms underlying the coumarins’ biological activity. The compounds are selected and grouped according to their cytotoxic, anticancer, antibacterial, antifungal, and miscellaneous effects
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