Katarzyna Wińska

Composition and antioxidant activity of red fruit liqueurs.

Fruits traditionally used for liqueurs are a good source of phenolic compounds endowed with antioxidant activity. The aim of this study was to compare the content of phenolic compounds and anthocyanins and the antioxidant capacity of liqueurs made from red fruits. The liqueurs were made from fruits of 10 species: chokeberry, cornelian cherry, black rose, blackcurrant, blackberry, raspberry, mahonia, sloe, strawberry, and sour cherry. The liqueurs from black rose, chokeberry, sloe and mahonia fruits contained the most of substances which react with the Folin-Ciocalteu reagent (671, 329, 271 and 218 mg GAE/100 mL, respectively) and had the highest antioxidant activity. The samples stored at a temperature of 30 °C had antioxidant activity from 3% to 11% lower than the fresh samples. After 6 months, anthocyanins degraded almost completely in the samples stored at 30 °C and at 15 °C there was from 0% (blackcurrant liqueurs) to 47% (sloe liqueurs) of their initial content and slightly more in sweet liqueurs.

Isoxanthohumol--Biologically active hop flavonoid.

Isoxanthohumol (IXN), apart from xanthohumol (XN) and 8-prenylnaringenin (8PN), is one of the most important prenylflavonoids found in hops. Another natural source of this compound is a shrub Sophora flavescens, used in traditional Chinese medicine. Main dietary source of IXN is beer, and the compound is produced from XN during wort boiling. In the human body, the compound is O-demethylated to 8PN, the strongest known phytoestrogen. This process takes place in the liver and in the intestine, where it is mediated by local microflora. It has been reported in some studies that even though beer contains small amounts of hops and its preparations, these compounds may affect the functioning of the human body. IXN exhibits an antiproliferative activity against human cell lines typical for breast cancer (MCF-7), ovarian cancer (A-2780), prostate cancer (DU145 and PC-3), and colon cancer (HT-29 and SW620) cells. It strongly inhibits the activation of the following carcinogens: 2-amino-3-methylimidazol-[4,5-f]quinoline and aflatoxin B1 (AFB1) via human cytochrome P450 (CYP1A2). It also inhibits the production of prostate specific antigen (PSA). IXN significantly reduces the expression of transforming growth factor-β (TGF-β) in the case of invasive breast cancer MDA-MB-231. It interferes with JAK/STAT signaling pathway and inhibits the expression of pro1inflammatory genes in the monoblastic leukemia cell line (MonoMac6). It activates apoptosis in human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HASMCs). In addition, IXN shows an antiviral activity towards herpes viruses (HSV1 and HSV2) and bovine viral diarrhea virus (BVDV).

Loliolide – the most ubiquitous lactone

Abstract The searching for biologically active compounds produced by living organisms led to the discovery of a number of compounds with more or less complicated structure. One of the simplest molecules are monoterpenoid lactones and loliolide is the most common among them. Loliolide was found in animals (insects) and plants (flowers, shrubs, trees) both terrestrial and marine, such as algae and corals. Many years of research on plants used in traditional folk medicine of different countries have led to the conclusion that this compound has a variety of biological properties such as anti-cancer, antibacterial, antifungal and antioxidant ones. Moreover, plants containing loliolide are used in alternative medicine in treatment of diabetes and depression. It is extremely interesting that this lactone also affects the behavior of ants as well as the development of certain plants (allelopathic activity). However, sometimes there are side effects as in the case of structural analogues of loliolide contributing to extinction of tropical coral. Streszczenie Poszukiwania związków biologicznie aktywnych wytwarzanych przez organizmy żywe doprowadziły do odkrycia wielu związków o mniej lub bardziej skomplikowanej strukturze. Jednymi z najprostszych cząsteczek są laktony monoterpenoidowe, zaś najczęściej spotykanym spośród nich jest loliolid. Loliolid spotykany jest w organizmach zwierzęcych (owady) i roślinnych (rośliny kwiatowe, krzewy, drzewa) zarówno lądowych jak i morskich takich jak glony lub koralowce. Wieloletnie badania prowadzone nad roślinami używanymi w tradycyjnej medycynie ludowej różnych krajów doprowadziły do stwierdzenia, że związek ten ma różnorodne właściwości biologiczne np. antynowotworowe, antybakteryjne, antygrzybiczne, antyoksydacyjne. Ponadto rośliny zawierające lioliolid są stosowane w medycynie alternatywnej przy leczeniu cukrzycy oraz depresji. Niezmiernie interesujący jest fakt, że lakton ten wywiera również wpływ na zachowanie mrówek jak i na rozwój niektórych roślin (aktywność alleplopatyczna). Czasami jednak można zaobserwować również działania niepożądane jak w przypadku analogów strukturalnych loliolidu mających swój udział w wymieraniu raf tropikalnych.

Influence of structure of lactones with the methylcyclohexene and dimethylcyclohexene ring on their biotransformation and antimicrobial activity

Abstract The aim of this article is influence of the structure of lactones with the methylcyclohexene and dimethylcyclohexene ring on their biotransformation and antimicrobial activity. This work was based on the general remark that even the smallest change in the structure of a compound can affect its biological properties. The results of the biotransformation of four bicyclic unsaturated lactones with one or two methyl groups in the cyclohexene ring was tested using fifteen fungal strains (Fusarium species, Penicillium species, Absidia species, Cunninghamella japonica, and Pleurotus ostreatus) and five yeast strains (Yarrowia lipolytica, Rhodorula marina, Rhodorula rubra, Candida viswanathii, and Saccharomyces cerevisiae). During these transformations, new epoxylactone and hydroxylactone were obtained. The relationship between the substrate structure and the ability of the microorganisms to transform them were analysed. Only compounds with C–O bond of lactone ring in the equatorial position were transformed by fungus. All presented here lactones were examined also for their antimicrobial activity. It turned out that these compounds exhibited growth inhibition of bacteria and fungi, mainly Bacillus subtilis, Candida albicans, Aspergillus niger, and Penicillium expansum.

Synthesis and Biotransformation of Bicyclic Unsaturated Lactones with Three or Four Methyl Groups

The aim of this study was to obtain new unsaturated lactones by chemical synthesis and their microbial transformations using fungal strains. Some of these strains were able to transform unsaturated lactones into different hydroxy or epoxy derivatives. Strains of Syncephalastrum racemosum and Absidia cylindrospora gave products with a hydroxy group introduced into a tertiary carbon, while the Penicillium vermiculatum strain hydroxylated primary carbons. The Syncephalastrum racemosum strain hydroxylated both substrates in an allylic position. Using the Absidia cylindrospora and Penicillium vermiculatum strains led to the obtained epoxylactones. The structures of all lactones were established on the basis of spectroscopic data.

Biotransformation of Bicyclic Halolactones with a Methyl Group in the Cyclohexane Ring into Hydroxylactones and Their Biological Activity

The aim of this study was the chemical synthesis of a series of halo- and unsaturated lactones, as well as their microbial transformation products. Finally some of their biological activities were assessed. Three bicyclic halolactones with a methyl group in the cyclohexane ring were obtained from the corresponding γ,δ-unsaturated ester during a two-step synthesis. These lactones were subjected to screening biotransformation using twenty two fungal strains. These strains were tested on their ability to transform halolactones into new hydroxylactones. Among the six strains able to catalyze hydrolytic dehalogenation, only two (Fusarium equiseti, AM22 and Yarrowia lipolytica, AM71) gave a product in a high yield. Moreover, one strain (Penicillium wermiculatum, AM30) introduced the hydroxy group on the cyclohexane ring without removing the halogen atom. The biological activity of five of the obtained lactones was tested. Some of these compounds exhibited growth inhibition against bacteria, yeasts and fungi and deterrent activity against peach-potato aphid.

Salt mine microorganisms used for the biotransformation of chlorolactones

The aim of the project was to find new catalysts capable of chlorolactone biotransformation. Three bicyclic chlorolactones with structures possessing one or two methyl groups in their cyclohexane ring were subjected to screening biotransformation using seven bacterial strains and one fungal strain from a salt mine. Three strains of bacteria (Micrococcus luteus Pb10, Micrococcus luteus WSP45, Gordonia alkanivorans Pd25) and one fungal strain (Aspergillus sydowii KGJ10) were able to catalyse hydrolytic dehalogenation of one substrate. The classification of the strains that were effective biocatalysts was confirmed by 16S rDNA analysis. The best result (76%) was obtained using Aspergillus sydowii KGJ10. All strains catalysed hydrolytic dehalogenation without changing the conformation. The equatorial position of the chlorine atom in the substrate turned out to be warrant of the positive result of the biotransformation process.

Phenolic Composition Stability and Antioxidant Activity of Sour Cherry Liqueurs

The aim of the study was to evaluate changes of phenolic and anthocyanin contents, antioxidant activity, aroma compounds and color of sour cherry liqueurs with and without sugar during 6 months of storage at temperatures of 15 °C and 30 °C. Contents of phenolic compounds (HPLC, UPLC-MS) and antiradical activity (ABTS) changes were measured. Color changes were measured by an objective method (ColorQuest XE). During storage fluctuations of phenolic compounds and antioxidant activity content were observed. The content of substances which react with Folin-Ciocalteu reagent was comparable before and after 24 weeks. During the 24 weeks of storage, the highest average antioxidant activity against ABTS radicals was shown by sour cherry liqueurs without sugar, stored at 15 °C. Quicker degradation of anthocyanins was observed in liqueurs without sugar, stored at 30 °C (t1/2—5.9 weeks in liqueurs with sugar and 6.6 weeks in liqueurs without sugar). Better stability of red color was observed in liqueurs with sugar, stored at 15 °C. The content of the dominant aroma compound, benzaldehyde, increased during storage. Long-term storage and sugar addition decreases color attributes but increases organoleptic value without of great influence on antioxidant activity. Studies on a half-year period of liqueur storage showed that their characteristic features are almost unchanged if stored at 15 °C and without sugar added, but organoleptic properties were better in samples stored at 30 °C.

Biotransformation of α-Acetylbutyrolactone in Rhodotorula Strains

Due to its structural similarity, the α’-1′-hydroxyethyl-γ-butyrolactone obtained by reduction of (±)-α-acetyl-γ-butyrolactone may have a similar function in the body to γ-butyrolactone (GBL). In the work presented, biotransformation of α-acetyl-γ-butyrolactone by three Rhodotorula strains was performed obtaining enantiomerically enriched alcohol. The process was carried out in growing and resting cultures. We studied how both media composition and organic solvent volume affected stereoselectivity and effectiveness of biotransformation. After 2 h, the enantiomerically pure (3R, 1′S)-α’-1′-hydroxyethyl-γ-butyrolactone was obtained using the R. marina AM77 strain in YPG (Yeast extract-Peptone-Glucose) medium enriched with 5% glycerol. To our best knowledge there is no previous information in the literature about the (±)-α-acetyl-γ-butyrolactone biotransformation performed in medium with addition of organic and deep eutectic solvents.

An Overview of Synthetic Methods for the Preparation of Halolactones

Halolactones are used both in chemical synthesis as intermediates as well as in various industries. These compounds may be secondary metabolites of living organisms, although they are mainly obtained by chemical synthesis. The substrates for the synthesis of chloro-, bromo- and iodolactones are often unsaturated carboxylic acids, and sometimes they are unsaturated esters. The article presents a number of different methods for the production of halolactones, both racemic mixtures and enantiomerically enriched compounds.