Lipoxygenase activity and sanguinarine production in cell suspension cultures of California poppy (Eschscholtzia californica CHAM.).

In this study we investigated the influence of biotic elicitor (phytopathogenic fungus Botrytis cinerea) and abiotic elicitors (methyljasmonate [MJ] and salicylic acid [SA]) on lipoxygenase (LOX) activity and sanguinarine production in cell suspension cultures of California poppy (Eschscholtzia californica CHAM.). We have observed different time effects of elicitors (10, 24, 48 and 72 h) on LOX activity and production of sanguinarine in in vitro cultures. All elicitors used in the experiments evidently increased the LOX activity and sanguinarine production in contrast to control samples. The highest LOX activities were determined in samples elicitated by MJ after 48 h and 72 h and the lowest LOX activities (in contrast to control samples) were detected after biotic elicitation by Botrytis cinerea. These activities showed about 50% lower level against the activities after MJ elicitation. The maximal amount of sanguinarine was observed after 48 h in MJ treated cultures (429.91 mg/g DCW) in comparision with control samples. Although all elicitors affect the sanguinarine production, effect of SA and biotic elicitor on sanguinarine accumulation in in vitrocultures was not so significant than after MJ elicitation.

[Antilipoxygenase activity and the trace elements content of Aloe vera in relation to the therapeutical effect]. / Antilipoxygenázová aktivita a obsah stopových prvkov Aloe vera vo vzt'ahu k terapeutickému úcinku.

Aloe vera is a rich source of many natural-health-promoting substances. The results of contemporary research on animal models indicate that the extracts have an antiinflammatory property. In this work the results of some in vitro experiments are shown: determination of the inhibitory effect of the Aloe vera extracts on the activity of partially purified lipoxygenase from the rat lung cytosol fraction, and quantitative determination of the trace elements presented in the extract (Mn, Fe, Cu, Zn) carried out by using the x-ray fluorescence analysis. The findings could explain the inhibitory effect (antilipoxygenase activity) of the Aloe vera extract in the acute inflammation process, expecially in the topical application for healing of minor burns and skin ulcers.

Head group specificity of phospholipase D isoenzymes from poppy seedlings (Papaver somniferum L.).

The biocatalytical potential of two new phospholipase D (PLD) isoenzymes from poppy seedlings (Papaver somniferum L.), PLD-A and PLD-B, was examined by comparing their activities in phospholipid transformation. Both enzymes showed the same ratio in rates of hydrolysis [phosphatidylcholine (PC):phosphatidylglycerol (PG):phosphatidylserine:phosphatidylinositol = 1:0.5:0.3:0.1] and were inactive towards phosphatidylethanolamine (PE). PLD-A did not catalyze head group exchange whereas PLD-B showed a high transphosphatidylation potential in the conversion of PC into PG and PE. This enzyme also catalyzed the transesterification of octadecylphosphocholine into octadecylphosphoglycerol or octadecylphosphoethanolamine.

[Isolation and characterization of active compounds from Aloe vera with a possible role in skin protection]. / Izolácia a charakterizácia ucinných obsahových látok Aloe vera s predpokladaným významom v ochrane koze.

Aloe vera is widely used in food supplements, beverages, pharmaceuticals, and cosmetics. It has been long recognized as an effective natural remedy for its wound-healing properties and its positive influence on other inflammatory skin disorders. Major proteins and mono- and polysaccharides were identified and analysed from Aloe vera commercial extract. Molecular weight of proteins calculated from the sets of molecular weight reference standards, ranged from 70 kDa for the largest to 14 kDa for the smallest ones. IR spectral analysis of the carbohydrate fraction shows that the main carbohydrate copound is acetylated (1 --> 4)-beta-D-mannan substituated with D-galactose and D-glucose. The results have shown that proteins and polysaccharides are a necessary component in the study of biological activity of Aloe vera leaf extract.

[Biochemical and molecular biology aspects of plant phospholipase D]. / Biochemické a molekulárno-biologické aspekty rastlinnej fosfolipázy D.

Phospholipase D (PLD) was first discovered in plants. It plays an important role in the regulation of cell functions not only in plants, but also in animal systems. It is interesting from the aspect of its dominant position in the signalling transduction processes. It controls the utilization of the membrane phospholipids for specific intentions--products of its catalytic activity are involved in intracellular communication processes. The study of the cell-regulation-system shows that PLD is a part of lipid-based signalling via octadecanoid pathway, which leads to the production of jasmonic acid, the basic signalling molecule in plants. PLD-mediated hydrolysis of the membrane phospholipids posed this enzyme into the level of the transmembrane and cell signalling participant. This area is interesting in the aspect of the production of biologically active compounds in plants. Because the signal-regulated synthesis of some secondary metabolites by the lipid signalling pathway has been already shown (induction of the gene expression coding the biosynthetic enzymes of flavonoids and terpenoids), the area of PLD study is perspective. This article is orientated on plant PLD and gives a basic review of its biochemical and molecular-biological properties (enzymology, molecular structure, subcellular localization, isoenzymes) and its physiological functions on the cell level (lipid signalling pathway, phospholipid degradation, phytohormones and cell signalling, growth, development and cell ageing, membrane remodeling).