Damjan Janeš

Screening of selected food and medicinal plant extracts for pancreatic lipase inhibition

Lipids are important components in human nutrition; however, their increased intake contributes to the development of obesity and can lead to multiple long‐term complications. Pancreatic lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) is a key enzyme for the absorption of dietary triglycerides. Interference with fat hydrolysis results in the reduced utilization of ingested lipids, therefore inhibition of lipases decreases fat absorption. Extracts from 106 species of medicinal plants, vegetables and fruits were screened for potential lipase inhibitory activity. p‐Nitrophenylpalmitate and 5‐bromo‐4‐chloro‐3‐indoxylpalmitate were used as substrates in an in vitro test with crude porcine pancreatic lipase. Bearberry (Arctostaphylos uva‐ursi), garden pea (Pisum sativum), Norway spruce (Picea abies) and large‐leaved lime (Tilia platyphyllos) extracts were the most active. Additionally, the activity of selected extracts with removed polyphenols was measured. Extracts of bearberry, garden pea and large‐leaved lime are a promising source for developing functional foods or isolating active compounds. Copyright

Salicylaldehyde is a characteristic aroma component of buckwheat groats.

Salicylaldehyde (2-hydroxybenzaldehyde) was identified as a characteristic component of buckwheat groats aroma by a sensory analysis guided fractionation of the extract. The extract with the strongest odour was prepared by petroleum ether extraction of water soaked groats. This extract was further extracted with sodium hydrogen carbonate solution and purified by a preparative layer chromatography and identified by NMR, MS and IR spectroscopy. A capillary electrophoresis method was developed and used to determine salicylaldehyde content in buckwheat groats and flour samples. Traditionally dehulled buckwheat grain, which had the strongest odour, contained the highest concentration (1.6ppm) of salicylaldehyde with an odour activity value (OAV) of 216.

Antibacterial Activity in Higher Fungi (Mushrooms) and Endophytic Fungi from Slovenia

Abstract Discovery and development of new antibiotics is still very important because of the constant appearance of drug-resistant pathogenic bacteria. The broth microdilution test was applied for screening of antibacterial activity in extracts of higher and endophytic fungi. Among tested extracts, three possessed significant antibacterial activity: extracts of mushrooms Amanita virosa. (Fr.) Bertill. (Amanitaceae) and Cortinarius praestans. Cordier (Cortinariaceae) against Pseudomonas aeruginosa. and Staphylococcus aureus., respectively, and extract of endophytic fungus Trucatella hartigii. (Tubeuf) Steyaert (Amphisphaeriaceae) against Enterococcus faecalis. and S. aureus.. The extract of Truncatella hartigii. was further analyzed by one- and two-dimensional thin-layer chromatography, and the position of the active compound was determined on the chromatogram.

Identification and Quantification of Aroma Compounds of Tartary Buckwheat (Fagopyrum tataricum Gaertn.) and Some of Its Milling Fractions

UNLABELLED Tartary buckwheat (Fagopyrum tataricum) seeds have a strong aroma that characteristically differs from the aroma of common buckwheat (Fagopyrum esculentum). Its phytochemical background has only been recently investigated. The aim of this study was to identify and quantify individual compounds responsible for tartary buckwheat aroma. Volatiles from different samples (whole seed, flour, and husks) were extracted with simultaneous extraction and distillation by Likens-Nickerson apparatus and analyzed by GC-MS. A total of 48 compounds were quantified and their odor activity values (OAV) were calculated. OAV of 26 compounds was higher than 10; therefore, they significantly contribute to the overall tartary buckwheat aroma. The compounds with OAV > 500 were: (E,E)-2,4-decadienal, (E)-2-nonenal, 2-phenylethanol, (E,E)-2,4-nonadienal, hexanal, decanal, and nonanal. The most important difference from the aroma of common buckwheat is the absence of salicylaldehyde and presence of naphthalene. Salicylaldehyde could be proposed as a marker to detect contamination/adulteration of tartary buckwheat with common buckwheat. PRACTICAL APPLICATION Buckwheat is becoming one of important alternative crops. Its products which are rich in proteins, fiber, vitamins, and antioxidants have been associated with healthy nutrition. Although tartary buckwheat is similar to more familiar common buckwheat, their characteristic aromas differ notably. This study expands recent research on aroma of tartary buckwheat tea to seed, flour, and husks, and suggests how products from different species of buckwheat can be distinguished by analysis of aroma compounds.

Aroma Compounds in Buckwheat (Fagopyrum esculentum Moench) Groats, Flour, Bran, and Husk

ABSTRACT Buckwheat is a pseudocereal with a strong characteristic aroma. Compounds responsible for the aroma of buckwheat groats were recently identified, but the distribution of aromatic compounds between different fractions of the buckwheat kernel (flour, bran, and husk) is not yet known. In this study, the composition of aromatic compounds in buckwheat seed fractions was investigated and compared to the composition of aromatic compounds in groats produced from the same batch of buckwheat seeds. Volatiles from each sample were extracted with simultaneous distillation/extraction with a Likens-Nickerson apparatus. Extracts were analyzed by gas chromatography coupled with mass spectrometry (GC-MS) with electron ionization. Apart from the aroma molecules present in all fractions, compounds that are present only in flour or bran, but not in groats, were also found. Furthermore, some compounds were identified only in buckwheat groats but not in buckwheat flour or bran [octanal, (E,E)-2,4-heptadienal, (E)-2-de...

The content of fagopyrin and polyphenols in common and tartary buckwheat sprouts

Abstract Dried buckwheat herb is used in medicinal products whereas fresh green plant parts, especially sprouts, are consumed as a vegetable. The herb contains fagopyrins, which cause sensitivity to light after ingestion. The aim of this study was to investigate the impact of different growing conditions and the development phase on the content of fagopyrin and phenolic compounds in buckwheat sprouts. Total flavonoid and total phenol contents, fagopyrin content and antioxidant activity were determined spectrophotometrically. Fagopyrin and flavonoids were located almost exclusively in cotyledons. Based on a comparison to hypericin toxicity, the recommendable intake of buckwheat sprouts was estimated to be less than 40 g per day.

Cathepsin H indirectly regulates morphogenetic protein-4 (BMP-4) in various human cell lines

Cathepsin H indirectly regulates morphogenetic protein-4 (BMP-4) in various human cell lines Background. Cathepsin H is a cysteine protease considered to play a major role in tumor progression, however, its precise function in tumorigenesis is unclear. Cathepsin H was recently proposed to be involved in processing of bone morphogenetic protein 4 (BMP-4) in mice. In order to clarify whether cathepsin H also regulates BMP-4 in humans, its impact on BMP-4 expression, processing and degradation was investigated in prostate cancer (PC-3), osteosarcoma (HOS) and pro-monocytic (U937) human cell lines. Materials and methods. BMP-4 expression was founded to be regulated by cathepsin H using PCR array technology and confirmed by real time PCR. Immunoassays including Western blot and confocal microscopy were used to evaluate the influence of cathepsin H on BMP-4 processing. Results. In contrast to HOS, the expression of BMP-4 mRNA in U937 and PC3 cells was significantly decreased by cathepsin H. The different regulation of BMP-4 synthesis could be associated with the absence of the mature 28 kDa cathepsin H form in HOS cells, where only the intermediate 30 kDa form was observed. No co-localization of BMP-4 and cathepsin H was observed in human cell lines and the multistep processing of BMP-4 was not altered in the presence of specific cathepsin H inhibitor. Isolated cathepsin H does not cleave mature recombinant BMP-4, neither with its amino- nor its endopeptidase activity. Conclusions. Our results exclude direct proteolytic processing of BMP-4 by cathepsin H, however, they provide support for its involvement in the regulation of BMP-4 expression.

Infuence of MHC on odour perception of 43 chemicals and body odour

The Major Histocompatibility Complex (MHC) is a large gene family that is found in most vertebrates and has an important influence on body odour preference and mate selection in animals. In this research we found, that human leukocyte antigen (HLA) phenotype is strongly connected with the strength and pleasantness of perceived odour of selected chemical compounds found in sweat. Among different chemical classes of compounds tested, the esters of fatty acids such as methyl undecanoate, methyl decanoate, methyl nonanoate, methyl octanoate and methyl hexanoate show strongest connection to HLA. On the other hand, our experiment did not confirm the connection of MHC to the perceived strength and pleasantness of body odour.

TLC densitometric method for screening of lycopsamine in comfrey root (Symphytum officinale L.) extracts using retrorsine as a reference compound

Abstract Due to severe toxicity of pyrrolizidine alkaloids, their quantification in medicinal products is very important. The idea of this research was to use retrorsine as a surrogate reference compound instead of lycopsamine reference or lycopsamine isolated from comfrey. A method for the analysis of lycopsamine in extracts of comfrey roots was developed and validated, employing thin layer chromatography, derivatisation with Dann-Mattocks reagent followed by densitometric analysis. The new method showed linearity within 0.70 to 7.0 μg of lycopsamine per application of 10 μL of a solution. It has also been proven to be specific and precise (repeatability RSD 2-4 % within the plate). The method was successfully employed for quantification of lycopsamine in comfrey root and comfrey root medicinal products such as ointments.