Effects of selected essential oils on the growth and production of ochratoxin A by Penicillium verrucosum

Eterična olja origana (Origanum vulgare L.), mete (Mentha piperita L.), janeža (Foeniculum vulgare Mill.), in borovih (Abies alba Mill.) iglic in storžev, ter njihove sestavine timol, karvakrol, mentol in anisaldehid smo testirali kot snovi z protiglivno aktivnostjo proti plesnim vrste Penicillium verrucosum. Najnižje minimalne inhibitorne koncentracije (MICs) smo določili eteričnemu olju origana, ter karvakrolu, timolu, in mentolu. Rast plesni vrste P. verrucosum je bila popolnoma inhibirana po 21 dneh inkubacije v prisotnosti ½ MIC timola (0,0625 mg mL-1), medtem ko so eterično olje origana (½ MIC, ¼ MIC), timol (¼ MIC) in karvakrol (½ MIC, ¼ MIC) inhibirali rast plesni od 8,3 % do 70.8 %. Dodatek mentola v koncentracijah ¼ MIC in ½ MIC (0.1875 mg mL-1 in 0.3750 mg mL-1) pa ni imel inhibitornega vpliva na rast plesni vrste P. verrucosum. Popolno inhibicijo tvorbe ohratoksina A smo določili le v primeru, ko je bila tudi rast teh plesni popolnoma inhibirana (pri ½ MIC timola). Največjo inhibicijo tvorbe ohratoksina A (96,9 %) po 21 dnevih inkubacije smo določili pri ¼ MIC timola (0.0313 mg mL-1). Pospešeno tvorbo ohratoksina A (od 13,9 % do 28,8 %) pa smo določili pri ¼ MIC eteričnega olja origana (0.2930 mg mL-1) in ½ MIC karvakrola (0.1953 mg mL-1). Protiglivni vplivi so bili odvisni od testirane snovi, njene koncentracije ter časa interakcij med protiglivno snovjo in plesnimi vrste P. verrucosum. Rezultati nakazujejo možnosti uporabe eteričnega olja origana v živilih namesto kemijskih konzervansov. Ker pa so živila kompleksna okolja v katerih je potrebno upoštevati več dejavnikov, so potrebne nadaljnje raziskave.Essential oils from oregano (Origanum vulgare L.), mint (Mentha piperita L.), fennel (Foeniculum vulgare Mill.), and pine (Abies alba Mill.) needles and cones, and their active substances thymol, carvacrol, menthol, and anisaldehyde were tested for antifungal activity against Penicillium verrucosum. The lowest minimal inhibitory concentrations (MICs) were achieved for essential oil of oregano, followed by carvacrol, thymol, and menthol. These antifungal components were further investigated, as the main aim of our study was to elucidate the effect of natural antifungals on ochratoxin A production. During 21 days of exposure, the growth of P. verrucosum, and subsequently the production of ochratoxin A, was fully inhibited by thymol at ½ MIC (0.0625 mg mL-1), but menthol at ¼ and ½ MIC (0.1875 and 3750 mg mL-1) showed no growth inhibition. After 21 days of incubation, the greatest inhibitory effect on ochratoxin production (inhibition was 96.9 %) was also achieved with thymol at ¼ MIC (0.0313 mg mL-1). Essential oil of oregano (¼ MIC, 0.2930 μL mL-1) and carvacrol (½ MIC, 0.1953 μL mL-1) stimulate production of ochratoxin A at 13.9 % to 28.8 %, respectively. The observed antifungal effects depended on the agent, the concentration used, and the time of interaction between the agent and P. verrucosum. Our results indicate the possibility of using oregano essential oil as a substitute for artificial preservatives in certain foods, but further research is needed

Marrubium vulgareL.: A Phytochemical and Pharmacological Overview

Marrubium vulgareis a plant with high bioactive potential. It contains marrubiin, a labdane diterpene that is characteristic for this genus, as well as a complex mixture of phenolic compounds. According to numerous studies,M. vulgareacts as a good antioxidant agent, and due to this, it could potentially be useful in treatments of cancer, diabetes mellitus, and liver diseases. In addition, its anti-inflammatory, wound-healing, antihypertensive, hypolipidemic, and sedative potential are discussed. Apart from that, its antimicrobial activity, especially against Gram+ bacteria, fungi, herpes simplex virus, and parasites such asToxoplasma gondii,Trichomonas vaginalis, andPlasmodium berghei-bergheiwas recorded. Additionally, it could be used as a chicken lice repellent, herbicide, and natural insecticide against mosquito larvae and natural molluscicide. In veterinary medicine,M. vulgarecan be used as an anthelmintic against the eggs and larvae of bovine strongyles parasites, and as an antibiotic against bovine mastitis caused by resistant bacterial strains. Due to the mentioned benefits, there is a tendency for the cultivation ofM. vulgarein order to ensure high-quality raw material, but more firm scientific evidence and well-designed clinical trials are necessary for the well-established use ofM. vulgareherb and its preparations

Antimicrobial and Resistance Modulatory Activity of Alpinia katsumadai Seed Phenolic Extract, Essential Oil and Post-Distillation Extract

Antimikrobna otpornost patogenih mikroorganizama predstavlja ozbiljan problem u proizvodnji hrane, a naročito zbog rastućeg broja multirezistentnih sojeva. Sve je veća potreba za novim i efikasnim antimikrobnim agensima i modulatorima otpornosti radi prevladavanja ovog problema, pri čemu biljke predstavljaju bogat izvor takvih spojeva. U ovom je radu ispitan antimikrobni učinak fenolnog ekstrakta, eteričnog ulja i destilacijskog ekstrakta sjemenki biljke Alpinia katsumadai, te njihov utjecaj na modulaciju otpornosti sojeva Campylobacter jejuni i Staphylococcus aureus. Ekstrakt sjemenki i postdestilacijski ekstrakt imali su relativno snažan antimikrobni učinak na bakteriju C. jejuni, dok je bakterija S. aureus pokazala veću otpornost. Fenolni ekstrakt, eterično ulje i destilacijski ekstrakt A. katsumadai u kombinaciji sa svim ispitanim antimikrobnim agensima (ciprofloksacin, eritromicin, triklosan, soli žučne kiseline i etidijev bromid) uspješno su modulirali otpornost svih sojeva C. jejuni. Učinak je ekstrakata i eteričnog ulja na bakteriju S. aureus ovisio o bakterijskom soju i primjenjenom antimikrobnom agensu, ali je uspješno smanjena otpornost svih sojeva na soli žučne kiseline. Eterično je ulje sjemenki biljke A. katsumadai potaklo akumulaciju etidijevog bromida unutar bakterijskih stanica, čime je dokazano da se može upotrijebiti kao inhibitor efluksne pumpe bakterija C. jejuni i S. aureus.Antimicrobial resistance of food-related bacterial pathogens is becoming a serious problem, especially after the emergence of multidrug-resistant strains. To overcome this problem, new and effective antimicrobials or resistance modulators are highly needed and plant kingdom represents a valuable source of these compounds. We investigated antimicrobial and resistance modulatory activity of the phenolic extract, essential oil and post-distillation extract of Alpinia katsumadai seeds against Campylobacter jejuni and Staphylococcus aureus. Among the tested plant formulations, A. katsumadai seed phenolic extract and post-distillation extract showed moderate antimicrobial activity against C. jejuni, while S. aureus was more resistant. When evaluating resistance modulatory potential of A. katsumadai phenolic extract, essential oil and post-distillation extract in C. jejuni against ciprofloxacin, erythromycin, triclosan, bile salts and ethidium bromide, plant formulations exhibited modulatory activity in combination with all antimicrobials. Modulation of resistance was more strain- and antimicrobial-specific in S. aureus, but very efficient in the case of reduced resistance to bile salts. Essential oil from A. katsumadai seeds efficiently increased intracellular ethidium bromide accumulation and was thus confirmed as potential inhibitor of efflux pumps in C. jejuni and S. aureus

Natural Products as Antibacterial Agents — Antibacterial Potential and Safety of Post-distillation and Waste Material from Thymus vulgaris L., Lamiaceae

Medicinal plants have a long tradition of use in folk and conventional medicine. In recent years numerous studies confirm various bioactivities of natural products, among them antibacterial activity. Natural antibacterial agents such are essential oils and isolated compounds now represent a notable source for pharmaceutical and food industry and are widely used in cosmetology. They meet standards of \u27green consumerism\u27 together with excellent antibacterial activity. Aromatic plants such is Thymus vulgaris L. are the major sources of essential oils. Thyme essential oil, as well as dominant compounds thymol and carvacrol are generally recognised as safe and have been registered by European Commission for use as flavouring agents in foodstuffs. However, essential oil is present in very low amount (0,8-2,6%) in thyme leaves. Thus, the majority of plant material remains unused after the isolation. Nowadays, the biological potential of various plant waste materials are in focus of numerous studies. These investigations also include the antimicrobial activity considering the fact that waste material extracts represent the valuable source of different phenolic compounds. Regarding all this, the aim of the present study was to determine antibacterial potential of chemically characterised extracts obtained from waste material remaining after the preparation of drug (stems) and isolation of thyme essential oil (deodorised leaves, postdistillation decoction) on selected bacterial strains. Also, in order to determine safety of waste extracts their cytotoxicity was investigated. All extracts were prepared with maceration using 45% or 75% ethanol (EtOH) for 24 h at room temperature (1:10 w/v). Total phenolic compounds and flavonoids were determined spectrophotometrically. Extracts were chemically characterized by HPLC/DAD analysis. Antibacerial testing was done with broth dilution method against several bacterial strains (Staphylococcus aureus, Bacillus cereus, Salmonella infantis, Escherichia coli and Campylobacter jejuni). Cytotoxicity and cytoprotection studies were performed by XTT assay. Result of HPLC analysis showed that investigated extracts, especially those obtained from deodorised leaves represent a valuable source of rosmarinic acid and luteolin 7-O-glucuronide. Antibacterial testing indicated that all waste material extracts, except the extract T2, possess similar or even stronger bacteriostatic activity than T1. No cytotoxicity nor cytoprotection were determined. In conclusion, results of this study confirmed antibacterial potential investigated thyme extracts. High concentrations of rosmarinic acid and luteolin 7-O-glucuronide, which both have numerous pharmacological activities, were determined. This indicates that thyme postdistillation waste material extracts could be used for isolation of dominant compounds or as addities in pharmaceutical and food industry

Hypericum perforatum

St. John’s wort is a widely used medicinal plant. The quality of herbal drug, which is in most of the cases collected from nature, varies. Therefore, the aim of the present study was detailed chemical characterization of Hypericum perforatum subsp. perforatum samples collected in close time intervals during flowering and fruitification with the purpose to state the phenological stage characterized by maximum levels of active principles. The antioxidant potential and potential to inhibit biologically important enzymes, as well as the cytotoxicity and genotoxicity of the sample collected during the full flowering period, were evaluated. Data showed that the optimal period for the achieving of maximum level of active principles is the phenophase between floral budding and flowering stage. Significant antioxidant potential and the ability to inhibit biologically important enzymes (especially α-glucosidase) were recorded. The extract exhibited no genotoxicity in subcytotoxic concentrations, while increased cytotoxicity recorded in cotreatment with bleomycin on malignant cell lines was especially significant

Anti-Inflammatory Properties of Plants from Serbian Traditional Medicine

Inflammation is a natural protective response of the human body to a variety of hostile agents and noxious stimuli. Standard anti-inflammatory therapy includes drugs whose usage is associated with a number of side effects. Since ancient times, natural compounds have been used for the treatment of inflammation. Traditionally, the use of medicinal plants is considered safe, inexpensive, and widely acceptable. In Serbia, traditional medicine, based on the strong belief in the power of medicinal herbs, is the widespread form of treatment. This is supported by the fact that Serbia is classified as one of 158 world centers of biodiversity, which confirms that this country is a treasure of medicinal herbs. Some of the most used herbs for the treatment of inflammations of various causes in Serbian tradition are yarrow, common agrimony, couch grass, onion, garlic, marshmallow, common birch, calendula, liquorice, walnut, St. John’s wort, chamomile, peppermint, white willow, sage, and many others. The biological activity and anti-inflammatory effect of selected plants are attributed to different groups of secondary biomolecules such as flavonoids, phenolic acids, sterols, terpenoids, sesquiterpenes, and tannins. This paper provides an overview of plants with traditional anti-inflammatory use in Serbia with reference to available studies that examined this effect. Plants used in traditional medicine could be a powerful source for the development of new remedies. Therefore intensive research on the bioactive potential of medicinal plants in each region should be the focus of scientists around the world

Highly invasive alien plant Reynoutria japonica Houtt. represents a novel source for pharmaceutical industry - evidence from phenolic profile and biological activity

Reynoutria japonica is on the IUCN list of the Worlds’100 worst invasive species, but it is also, especially its rhizome, an integral part of traditional chinese medicine. The objective of this study was to determine the amount of selected phenolic compounds in rhizome, stems, leaves and inflorescence methanol extracts of this plant, their antioxidant and anticholinesterase activity. The chemical profile of the examined extracts was obtained by a high-performance liquid chromatography. In vitro assays on DPPH, OH and NO radicals were used to estimate antioxidant potential and Ellman’s method was applied for the determination of anticholinesterase activity. Leaves and rhizome extracts were found to be rich in rosmarinic and chlorogenic acid, and selected flavonoids. Resveratrol was exclusively present in rhizome and stems extracts. All the investigated extracts expressed certain antioxidant activity, where leaves extract was the most active. However, rhizome extract was the strongest inhibitor of acetylcholinesterase. These findings indicate that there is a possibility of R. japonica exploitation for the isolation of biologically active phenolic compounds used in pharmaceutical and food industry

Chemical composition and antioxidant activity of O. vulgare var. vulgare and var. heracleoticum

Oregano (Origanum vulgare) is an aromatic plant from the Lamiaceae family. Due to its rich content of polyphenols, flavonoids and other important secondary metabolites, oregano have anti-inflammatory, antioxidant, and antimicrobial properties. This research was aimed to compare the chemical composition of O. vulgare var. vulgare and var. heracleoticum and their antioxidant activity. Investigated extracts were prepared by ethanol maceration. The total phenolic content was determined by the Folin-Ciocalteu method. The total amount of flavonoids was determined spectrophotometrically by analysing flavonoid complex formation with AlCl3. Chemical characterization was performed by high-performance liquid chromatography. The ability of the tested extract to neutralize 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH•) and nitroso (NO•) radicals was tested by the spectrophotometric methods. The total phenolic content was аpproximately equal in both, O. vulgare var. vulgare and var. heracleoticum (87.53 and 90.5 mg of the gallic acid equivalents/g dry extract, respectively). Also, the total amount of flavonoids was аpproximately equal in both, O. vulgare var. vulgare and var. heracleoticum (21.8 and 23.23 mg of the quercetin equivalents/g dry extract, respectively). Rosmarinic, ferulic and chlorogenic acids, and rutin were identified as dominant polyphenolic compounds. Moreover, antioxidant activity of both extracts was similar. Half-maximal inhibitory concentration (IC50) for DPPH was 2.28 mg/mL for O. vulgare var. vulgare and 2.59 mg/mL for O. vulgare var. heracleoticum. The ability of the tested extract to neutralize NO• was similarly good for both extracts (IC50= 17.71 and 20.53 mg/mL). The tested extracts showed weaker activity in neutralizing OH• (IC50= 285.37 and 192.24 mg/mL). Due to the similarity in chemical composition and antioxidant activity both varieties can be used as medicinal herbal drugs

Artemisia annua L. (Asteraceae) – Chemical analysis and antioxidative activity

Artemisia annua, u narodu poznata kao slatki pelin, je zeljasta biljka iz familije Asteraceae. Od davnina se upotrebljava u tradicionalnoj medicini kao biljka koja ima antimalarijsku aktivnost, usled prisustva seskviterpenskog laktona artemisina. Takođe, sadrži fenole i flavonoide, te se svrstava u biljke sa antioksidativnim, antiinfektivnim i antiinflamatornim dejstvom. Cilj rada bilo je ispitivanje hemijskog sastava i antioskidativne aktivnosti etanolnog ekstrakta slatkog pelina. U etanolnom ekstraktu herbe A. annua određen je sadržaj ukupnih fenola metodom po Folin-Ciocalteu. Rezultati su izraženi kao mg ekvivalenta galne kiseline/g suvog ekstrakta (mg EGK/g s.e.). Ukupni flavonoidi određeni su spektrofotometrijski praćenjem formiranja kompleksa sa AlCl3. Rezultati su izraženi kao mg ekvivalenta kvercetina/g suvog ekstrakta (mg EK/g s.e.). Antioksidativna aktivnost određena je in vitro testovima inhibicije 2,2-difenil-1-pikrilhidrazil (DPPH), hidroksil (OH), nitrozo (NO) radikala i testom inhibicije lipidne peroksidacije. Rezultati su izraženi kao koncentracija pri kojoj je neutralisano 50% radikala tj. koncentracija pri kojoj je inhibisano 50% procesa lipidne peroksidacije (IC50). Visokoefikasnom tečnom hromatografijom (HPLC) izvršena je detaljna hemijska karakterizacija. Rezultati su izraženi kao μg/g suvog ekstrakta.Artemisia annua, popularly known as sweet wormwood, is a herbaceous plant from the family Asteraceae. Since ancient times, it has been used in traditional medicine as a plant that has antimalarial activity, due to the presence of the sesquiterpene lactone artemisinin. It also contains phenols and flavonoids because it is classified as a plant with antioxidant, anti -infective and anti-inflammatory effects. The aim of the work was to examine the chemical composition and antioxidative activity of the ethanolic extract of sweet wormwood. In the ethanolic extract of A. annua herb, the content of total phenols was determined using the Folin-Ciocalteu method. The results are expressed as mg gallic acid equivalents/g dry extract (mg GAE/g d.e.). Total flavonoids were determined spectrophotometrically by monitoring the formation of complexes with AlCl3. Results are expressed as mg quercetin equivalents/g dry extract (mg QE/g d.e.). Antioxidant activity was determined by in vitro tests of inhibition of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH), nitroso (NO) radicals and lipid peroxidation inhibition test. The results are expressed as the concentration at which 50% of the radicals are neutralized, or the concentration at which 50% of the lipid peroxidation process is inhibited (IC50). Detailed chemical characterization was investigated by high-performance liquid chromatography (HPLC). The results are expressed as μg/g dry extract

Hemijski sastav i antioksidantna aktivnost žućkastog sporiša (Achillea nobilis L. subsp. neilreichii (Kerner) Velen.)

Species of the genus Achillea are well-known ancient medicinal plants. Noble yarrow is presented in eastern Serbia, Suva planina and Kosovo (around Peja). Due to the traditional use, it is important to determine the chemical composition and biological activities of these species widespread in Serbia. The aim of this study was to determine the chemical composition and antioxidant activity of noble yarrow. The content of total phenols in the prepared infusion was determined by the Folin – Ciocalteu method. Total flavonoids were determined spectrophotometrically by forming complexes with AlCl3. Chemical characterization was performed by high performance liquid chromatography. The antioxidant activity was examined spectrophotometrically by determining the "scavenger" activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl (OH •) radical and nitroso (NO •) radical, as well as redox potential testing by FRAP test and determination of inhibition lipid peroxidation in the Fe2 + / H2O2 induction system. The total phenol content in the tested infusion was 33.52 mg of gallic acid equivalent per gram of dry extract, while the content of total flavonoids was 6.79 mg of quercetin equivalent per gram of dry extract. Phenolic acids are dominantly presented in the infusion. Rosmarinic and p-coumaric acids are the most abundant (13.34 and 12.74 mg/g of dry extract). The infusion showed the ability to neutralize free radicals at medium high concentrations. Unlike the results of other antioxidant tests, inhibition of lipid peroxidation was not achieved. The tested plant is a good source of phenolic compounds with established antioxidant activity.Vrste roda Achillea su široko rasprostranjene lekovite biljke sa poznatom tradicionalnom primenom od davnina. Achillea nobilis L. subsp. neilreichii (Kerner) Velen., u narodu poznata kao žućkasti sporiš, rasprostranjena je na teritoriji istočne Srbije, Suve planine i Kosova (okolina Peći). Zbog raširene tradicionalne primene, značajno je da se detaljno prouče hemijski sastav i biološke aktivnosti vrsta roda Achillea rasprostranjenih u Srbiji, pa je cilj ovog rada bio da se odrede hemijski sastav i antioksidantna aktivnost infuza žućkastog sporiša. U pripremljenom infuzu određen je sadržaj ukupnih fenola metodom po Folin–Ciocalteu. Ukupni flavonoidi određeni su spektrofotometrijski praćenjem formiranja kompleksa sa AlCl3. Hemijska karakterizacija izvršena je visokoefikasnom tečnom hromatografijom. Antioksidativno delovanje infuza ispitano je spektrofotometrijski određivanjem „skevindžer“ aktivnosti na 2,2-difenil-1-pikrilhidrazil (DPPH), hidroksil (OH•) radikal i nitrozo (NO•) radikal, kao i ispitivanjem redoks potencijala pomoću FRAP testa i određivanjem inhibicije lipidne peroksidacije u Fe2+/H2O2 sistemu indukcije. Sadržaj ukupnih fenola u ispitivanom infuzu je 33,52 mg ekvivalenata galne kiseline po gramu suvog ekstrakta, dok je sadržaj ukupnih flavonoida 6,79 mg ekvivalenata kvercetina po gramu suvog ekstrakta. U infuzu su dominantno prisutne fenolne kiseline od kojih su najzastupljenije rozmarinska (13,34 mg/g suvog ekstrakta) i p-kumarna kiselina (12,74 mg/g suvog ekstrakta). Infuz je pokazao sposobnost da neutralizuje slobodne radikale pri srednje visokim koncentracijama. Za razliku od rezulata ostalih antioksidativnih testova, pomoću analiziranog infuza nije postignuta inhibicija lipidne peroksidacije. Ispitivana biljka predstavlja dobar izvor fenolnih jedinjenja sa utvrđenim antioksidantim delovanjem