Terpenes are naturally occurring substances produced by a wide variety of plants and animals. A broad range of the biological properties of terpenoids is described, including cancer chemopreventive effects, antimicrobial, antifungal, antiviral, antihyperglycemic, anti-inflammatory, and antiparasitic activities. Terpenes are also presented as skin penetration enhancers and agents involved in the prevention and therapy of several inflammatory diseases. Moreover, a potential mechanism of their action against pathogens and their influence on skin permeability are discussed. The major conclusion is that larger-scale use of terpenoids in modern medicine should be taken into consideration.
The study of organic/inorganic molecules with activity against intracellular fungi of the phylum Microsporidia is of critical importance. Here, for the first time, the inactivation of these parasitic fungi by porphyrins is reported. The biological effects of porphyrins (10 µM and 100 µM) on the microsporidian Nosema ceranae was investigated in honeybee hosts using cage experiments. A significant reduction in the number of spores (from 2.6 to 5 fold) was observed in Nosema-infected honeybees with a sucrose-protoporphyrin amide [PP(Asp)2] syrup diet compared to the control honeybees. PP(Asp)2 and the other porphyrin examined in vitro, TMePyP, had a direct impact on the microsporidia. Notably, neither porphyrin requires light excitation to be active against microsporidia. Moreover, microsporidia preincubated with these porphyrins exhibited decreased ability to infect honeybees. In particular, PP(Asp)2, possessing amphiphilic characteristics, exhibited significant inactivation of microsporidia, preventing the development of the microsporidia and diminishing the mortality of infected honeybees. In addition, the porphyrin-treated spores examined by scanning electron microscopy (SEM) showed morphological changes in their exosporium layers, which were distinctly deformed. Thus, we postulate that the mechanism of action of porphyrins on microsporidia is not based on photodynamic inactivation but on the destruction of the cell walls of the spores.
Context Biotransformation systems are profitable tools for structural modification of bioactive natural compounds into valuable biologically active terpenoids. Objective This study determines the biological effect of (R)-(+)-limonene and (−)-α-pinene, and their oxygenated derivatives, (a) perillyl alcohol and (S)-(+)- and (R)-(−)-carvone enantiomers and (b) linalool, trans-verbenol and verbenone, respectively, on human colon tumour cells and normal colonic epithelium. Materials and methods Biotransformation procedures and in vitro cell culture tests were used in this work. Cells were incubated for 24 h with terpenes at concentrations of 5–500 μg/mL for NR, MTT, DPPH, and NO assays. IL-6 was determined by ELISA with/without 2 h pre-activation with 10 μg/mL LPS. Results trans-Verbenol and perillyl alcohol, obtained via biotransformation, produced in vitro effect against tumour cells at lower concentrations (IC50 value = 77.8 and 98.8 μg/mL, respectively) than their monoterpene precursors, (R)-(+)-limonene (IC50 value = 171.4 μg/mL) and (−)-α-pinene (IC50 value = 206.3 μg/mL). They also showed lower cytotoxicity against normal cells (IC50 > 500 and > 200 μg/mL, respectively). (S)-(+)-Carvone was 59.4% and 27.1% more toxic to tumour and normal cells, respectively, than the (R)-(−)-enantiomer. (R)-(+)-limonene derivatives decreased IL-6 production from normal cells in media with or without LPS (30.2% and 13.9%, respectively), while (−)-α-pinene derivatives induced IL-6 (verbenone had the strongest effect, 60.2% and 29.1% above control, respectively). None of the terpenes had antioxidative activity below 500 μg/mL. Discussion and conclusions Bioactivity against tumour cells decreased in the following order: alcohols > ketones > hydrocarbons. (R)-(+)-limonene, (−)-α-pinene, and their derivatives expressed diverse activity towards normal and tumour cells with noticeable enantiomeric differences.
Three different Fusarium culmorum strains having a pathogenic, a deleterious (deleterious rhizosphere microorganism), or a promoting (plant growth promoting fungus) effect on plant growth were studied for their ability to synthesize in vitro the phytohormones indoleacetic acid (IAA), gibberellic acid (GA), and ethylene. All the phytohormones tested were synthesized in cultures supplemented with wide concentration ranges of glucose and tryptophan or methionine (precursors of phytohormone synthesis). The amounts of these secondary metabolites synthesized by the particular strains were found to be significantly different. The non-pathogenic PGPF strain (DEMFc2) synthesized the highest amounts of IAA and GA, a fact that could be responsible for the growth-promoting properties of this strain. A pathogenic strain synthesized the highest amount of ethylene, which could be responsible for the negative effect of this strain on plant growth. F. culmorum isolates with a high capacity for IAA synthesis also have a high capacity for GA synthesis and irrespective of the growth conditions, a high positive correlation (R > 0.9) between the concentrations of synthesized IAA and GA in F. culmorum cultures was found. It is worth mentioning that the optimal conditions for the growth of F. culmorum isolates and the synthesis of the individual phytohormones differed from one another. The optimal growth conditions were 1.0% of glucose and 9.9 mM of methionine or 6.0 mM of tryptophan. The optimal conditions for ethylene synthesis were 0.5% of glucose and 6.6 mM of methionine, whereas 1.0% of glucose and 9.0 mM of tryptophan were optimal for IAA and GA synthesis.
21 April 2015 in Journal of Industrial Microbiology and Biotechnology
New glycidyl methacrylate copolymers containing different numbers of epoxy groups were synthesized and used to develop effective procedures for inulinase immobilization. The beneficial characteristics of the carriers included a high degree of crosslinking, stability at ambient temperature, an appropriate surface, and the presence of reactive epoxy groups. Some factors affecting the efficiency of immobilization of crude inulinase, including the kind and amount of carrier, the number of epoxy groups, as well as buffer pH and buffer concentration were examined. The yield of immobilization of this enzyme on the investigated type of microspheres was higher than on the commercial carrier, Eupergit® C. After immobilization, the optimum temperature for inulinase activity shifted from 55 to 45 °C, whereas the optimum pH = 5 remained unchanged. The basic parameters of inulin hydrolysis were examined, and the possibility of applying the obtained biocatalyst in continuous conditions was tested. Inulin at a concentration of 0.5 % (w/v) was almost completely hydrolyzed to fructose (in a yield of 98 %) at a flow rate of 0.1 mL/min. A tenfold increase in the speed of flow resulted in an increase in the yield of oligosaccharides (DP2-DP6) up to ~41 % in the overall hydrolysate, as analysed by HPLC-RID and LC-ESI/MS. These results indicate that two forms of inulinase, an exo- and an endo-acting enzyme, were immobilized on our carrier. The enzyme showed good operational stability in a packed column over 28 days. There were no significant decreases in the efficiency of continuous hydrolysis during this time (about 17.4 % in comparison to its initial value).