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Naravne snovi so spojine ali ekstrakti, ki izvirajo iz živih organizmov ter navadno izkazujejo biološko delovanje. So osnovna surovina za zdravila naravnega izvora. V farmakognoziji se ukvarjamo z njihovim izborom, karakterizacijo, identifikacijo in uporabo. Pogost pristop k odkrivanju potencialno zdravilnih naravnih snovi je preizkušanje učinkov rastlinskih izvlečkov, ki nas v povezavi s kromatografskimi separacijami vodi do izolacije biološko aktivnih molekul. Njihove kemijske strukture ugotavljamo s sodobnimi spektroskopskimi in spektrometrijskimi metodami in nadaljujemo s preizkušanjem njihovega farmakološkega delovanja. Ajda predstavlja bogat vir hranil z ugodnim vplivom na zdravje, zato njena poraba v skladu s popularnostjo zdravega načina življenja narašča. Poleg zdravju koristnih snovi pa ajda vsebuje tudi manj znane, fototoksične fagopirine, ki pod vplivom svetlobe oksidirajo biološko snov in povzročijo njene poškodbe. Za zagotavljanje varnosti ajde in njenih izdelkov je treba fagopirine vrednotiti tako s prehranskega kot s farmacevtskega vidika. Ne nazadnje gre tudi za spojine s potencialno terapevtsko uporabnostjo, na primer v fotodinamični terapiji. Razvili smo učinkovit postopek ekstrakcije fagopirinov z uporabo raztopine acetona in vode. Ugotovili smo, da so najprimernejši material za pridobivanje fagopirinov ajdovi cvetovi. Razvili smo preprosto in občutljivo metodo tekočinske kromatografije visoke ločljivosti s fluorescentno detekcijo. Metoda je primerna za analizo vzorcev ajde in kot izhodišče za razvoj preparativne metode za izolacijo fagopirinov. Ugotovili smo, da je poleg osnovne molekule fagopirina F v zeli ajde še vsaj sedem njegovih derivatov. Te derivate smo kromatografsko ločili na posamezne frakcije. Vrednotili smo jih z UV-Vis absorpcijo, masno spektrometrijo in NMR spektroskopijo. Ugotovili smo strukturi dveh novih fagopirinov, ki se razlikujeta po skupinah, pripetih na naftodiantronski obroč. Fagopirin F je že predhodno znana spojina z dvema piperidinskima obročema, fagopirin E je spojina s piperidinskim in pirolidinskim obročem, fagopirin A pa je spojina z dvema pirolidinskima obročema. Dokazali smo, da v ajdi ni fagopirinov, temveč zgolj protofagopirini kot njihove predstopnje z necikliziranim naftodiantronskim obročem. Po raztopitvi v ekstrakcijskem topilu in pod vplivom svetlobe se protofagopirini pretvorijo v fagopirine. Raziskovali smo topnost, fluorescenco in UV-Vis spektre fagopirinov v različnih topilih iz različnih vzorcev ajde. Za kvantitativno vrednotenje vsebnosti fagopirinov je treba pridobiti čiste spojine kot referenčne spojine. Raziskovalci namesto fagopirina kot referenčne spojine uporabljajo hipericin iz šentjanževke, ki pa zaradi nekoliko drugačne strukture in s tem drugačne absorpcije pri spektrofotometrijski detekciji ni ustrezen za točno kvantitativno vrednotenje fagopirinov. Naše ugotovitve in novo razvite metode bodo pripomogle k nadaljnjemu raziskovanju fagopirinov in vrednotenju vsebnosti in varnosti ajdovih izdelkov. V drugem delu doktorskega dela smo se ukvarjali z izvlečki debla navadne jelke. Izvlečki debel različnih vrst borovcev so znani po vsebnosti polifenolnih spojin z zanimivimi farmakološkimi učinki, predvidoma povezanimi z antioksidativnim delovanjem. Najbolj znan, raziskan in uporabljan je izvleček lubja obmorskega bora (Pinus maritima), Pycnogenol®. Ugotovili smo, da so izvlečki navadne jelke učinkovitejši antioksidanti od Pycnogenola® tako v in vitro antioksidativnih testih, kot tudi na humanih celičnih linijah, izoliranih iz periferne krvi. Komponente izvlečka lubja smo kromatografsko ločili z normalnofazno kolonsko kromatografijo pri zvišanem tlaku in reverznofazno tekočinsko kromatografijo visoke ločljivosti. Vsebovane spojine smo identificirali z metodami masne spektrometrije, UV-Vis absorpcijske spektroskopije in s primerjavo z referenčnimi spojinami. Identificirali smo šest fenolkarboksilnih kislin (galno, homovanilno, protokatehujsko, p-hidroksibenzojsko, vanilno in p-kumarno), tri flavonoide (katehin, epikatehin in katehintetrametileter) in štiri lignane (taksiresinol, 7-(2-metil-3,4-dihidroksitetrahidropiran-5-iloksi)-taksiresinol, sekolariciresinol in lariciresinol). Nadaljevali smo s farmakološkim testiranjem. Ugotovili smo, da izvleček zmanjša nastajanje ateroskleroze pri budrah na kronični aterogeni dieti. Ovrednotili smo vpliv izvlečka in dveh v njem prisotnih fenolnih kislin, p-kumarne in protokatehujske, na izolirana podganja srca, podvržena akutnim ishemijsko-reperfuzijskim poškodbam. Ugotovili smo, da je izvleček značilno zmanjšal poškodbo srčnega tkiva, merjeno preko sproščanja laktat-dehidrogenaze in zmanjšal pojavnost aritmij. p-kumarna in protokatehujska kislina nista imeli tako izrazitih učinkov, zato verjetno samo delno prispevata k sinergističnemu delovanju v izvlečku prisotnih učinkovin. Kot ustrezno surovino za raziskovanje in uporabo smo oblikovali izvleček, raztopljen v polietilenglikolu. Pojavila se je potreba po ugotavljanju vsebnosti vode v tovrstnih vzorcih. Uveljavljena in dostopna Karl-Fischer metoda z opazovanjem spremembe barve pri končni točki titracije ni bila ustrezna, saj je bil izvleček obarvan. Zato smo razvili preprosto in finančno dostopno titracijsko metodo za ugotavljanje vsebnosti vode v obarvanih vzorcih, pri kateri končno točko titracije zaznamo spektrofotometrijsko. Tako ovrednoten izdelek predstavlja dobro osnovo za nadaljnje raziskovanje in razvijanje novih prehranskih dopolnil, kozmetičnih izdelkov in zdravil. Natural products are compounds or extracts that originate from natural sources and usually exhibit biological activity. They are raw materials for natural medicines. Pharmacognosy encompasses their selection, characterization, identification and use. Bioassay-guided fractionation of plant extracts linked to chromatographic separation techniques leads to the isolation of biologically active compounds whose chemical structures can readily be determined by modern spectroscopic and spectrometric methods, followed by testing of their pharmacological activity.Buckwheat contains many healthy nutrients, and its consumption is therefore increasing. The plant contains phototoxic compounds called fagopyrins that can act as photosensitisers upon excitation with visible light causing fagopyrism, but these compounds have received little research attention. To assure adequate safety of buckwheat and its products, fagopyrins should be characterized from a nutritional and pharmaceutical point of view. Nevertheless, fagopyrins are not only health-threatening compounds but also potent photodynamic agents that deserve further research. In this work, fagopyrins extraction procedure was improved employing a mixture of acetone and water. Flowers were recognized as the best material for the extraction. A chromatographic analysis of fagopyrins was performed by developing a simple, sensitive HPLC analytical method of high-resolution employing fluorescence detection. The developed method is a good starting point for a preparative method that would enable the isolation of pure compounds. At least eight fagopyrin derivatives were observed upon isolation and were characterized via UV-Vis absorption, NMR spectroscopy and mass spectrometry. The structures of two new fagopyrins were elucidated. Fagopyrin F is a previously known compound that consists of naphthodianthrone scaffold and two piperidine moieties. Fagopyrin A differentiates by two pyrrolidine moieties instead of piperidine moieties, and fagopyrin E consists of one pyrrolidine and one piperidine moiety. The existence of protofagopyrins that originate in buckwheat and can transform into fagopyrins upon light exposure was confirmed. Information on solubility, fluorescence and UV-Vis absorbance in different solvents were obtained. The need for reference compounds of different fagopyrins that would allow proper quantitative evaluation of buckwheat samples still remains. Researchers use hypericin for that purpose, but we recognize its use as inadequate due to the different structure and consequently uncomparable absorbance in spectrophotometric detection. Our methods complement the existing knowledge regarding fagopyrins and will facilitate their further isolation and analysis of their biological activity. In the second part of our work, silver fir trunk extracts were investigated. Extracts from the bark of different conifer species are known to contain various polyphenols that possess interesting pharmacological activities. So far the most extensive research was done on the antioxidative extract of the maritime pine (Pinus maritima) bark Pycnogenol®, which is widely used in food supplements and cosmetic products. We have shown that antioxidant activity of silver fir (Abies alba) extract is higher comparing to the maritime pine bark extract in vitro and in cultured cells. Components of the extract were separated with normal phase flash chromatography and reversed phase HPLC. Structures of individual compounds were elucidated by mass spectrometry, UV-Vis absorption spectroscopy and comparison to reference compounds. Six phenolic acids were identified (gallic, homovanillic, protocatehuic, p-hydroxybenzoic, vanillic and p-coumaric), three flavonoids (catechin, epicatechin and catechin tetramethyl eter) and four lignans (taxiresinol, 7-(2-methyl-3,4-dihydroxytetrahydropyran-5-yloxy)-taxiresinol, secoisolariciresinol and laricinresinol).The research was continued with pharmacological testing. It was found that the extract exerts strong antioxidative and protective effects against atherogenic diet-induced arterial wall damage. Protective effects of the silver fir extract and its compounds as well as of two phenolic acids (p-coumaric and protocatechuic acids) were also evauated against ischemia-reperfusion-induced damage in isolated rat hearts. The silver fir extract significantly reduced tissue damage (measured as the lactate dehydrogenase release rate) and shortened the duration of arrhythmias, which was not observed in the case of phenolic acids. It was concluded that the two acids are only partially responsible for the observed effects and synergism of more compounds could be present. Silver fir extract, solubilized in polyethylene glycol was developed as an appropriate raw material for research and use. A need for water determination in such samples emerged. The most accessible technique for water content determination is Karl-Fischer titration with visual detection of a titration endpoint, which was unfortunately not suitable for the analysis of the silver fir extract due to its strong colour. Therefore an appropriate method for moisture determination in coloured samples was developed employing simple equipment and spectrophotometric detection of a titration endpoint. Silver fir extract, characterized in such manner is a suitable ingredient for development of food supplements, cosmetic products and medicines.

Uvod: Veliko ljudi zelo pogosto uporablja kopalne bazene za različne namene. Z večjo frekvenco uporabnikov bazenov je treba zagotoviti skladno kopalno vodo za vse uporabnike bazena. Za zagotavljanje skladne kopalne vode se uporablja dezinfekcija. Z dezinfekcijo preprečimo prenos širjenja mikroorganizmov. Poleg zatiranja mikroorganizmov pa dezinfekcijsko sredstvo reagira tudi s snovmi, ki jih človek vnese v kopalno vodo. Ob reakciji nastajajo različni stranski produkti dezinfekcije. Namen: Namen magistrskega dela je raziskati področje nastanka stranskih produktov pri dezinfekciji kopalne vode ob sočasni uporabi rastlinskih ekstraktov. Metode dela: Najprej smo pregledali obstoječo literaturo, na podlagi katere smo nato nadaljevali z laboratorijskim delom. Na podlagi pridobljenih podatkov smo nato pripravili simulacijo zeliščne kopeli. Grelec je v zeliščni kopeli zagotavljal stalno temperaturo 35 °C. Vzorce smo v kopelih segrevali v erlenmajericah in vialah. Vse vzorce smo iz zeliščne kopeli odvzemali v naprej določenih časovnih intervalih in jih analizirali z metodo SPME vlakna (vzorci plinske faze) ali pa z ekstrakcijo tekoče/tekoče (vzorci vodne faze). Sete analiz smo izvedli tako v destilirani kot morski vodi. Po odvzemu vzorcev za analizo vodne faze je bilo treba vzorce ekstrahirati z diklorometanom, jih upariti ter nato analizirati na GC-MS. Vzorcev za analizo plinske faze predhodno ni bilo treba posebno pripraviti. Analiza vzorcev je potekala na plinskem kromatografu. Analizi je nato sledila še identifikacija spojin, ki so nastale med postopkom kloriranja. Rezultati: Z eksperimentalnim delom smo dokazali pojavnost stranskih produktov, ki v vodi nastanejo ob sočasni uporabi dezinfekcijskega sredstva in rastlinskega ekstrakta, v našem primeru limonena. V vseh odvzetih vzorcih, odvzetih ob različnih časovnih obdobjih, smo identificirali 18 različnih spojin. Spojine smo identificirali tako v vodni kot v plinski fazi vzorcev. V vodni fazi smo identificirali več različnih produktov kot v plinski fazi. Stranske produkte dezinfekcije smo identificirali tako ob uporabi destilirane kot tudi morske vode. Tekom kloriranja smo identificirali različne okside, primarne, sekundarne in terciarne produkte kloriranja ter primarne produkte bromiranja v morski vodi. Razprava in zaključek: V vzorcih, ki so bili postopku kloriranja izpostavljeni dalj časa, smo identificirali več različnih spojin kot pri vzorcih, ki so bili postopku kloriranja izpostavljeni manj časa. V vzorcih, odvzetih pri povišani temperaturi, smo dokazali pojavnost oksidov, ki jih pri vzorcih, odvzetih pri sobni temperaturi, nismo zaznali. V vzorcih z morsko vodo smo identificirali spojine z bromom, ki jih vzorci z destilirano vodo niso vsebovali. V nekaterih vzorcih smo zaznali nastanek trihalometanov. Introduction: Many people use thermal pools for different purposes. However, with the greater frequency of the users, it is necessary to provide pool water in accordance with the regulations for all users. To ensure that, disinfection is used. With disinfection, we prevent the transfer of dispersal of microorganisms. Besides that, disinfection agent also reacts with the substances in the pool water, brought in water by the people. That reaction produces different disinfection by-products. Purpose: The purpose of this Master thesis is to research the area of origin of the side products present at the disinfection of pool water with the simultaneous use of herbal extracts. Methods: First, we looked at the existing literature on which we based our research. Based on the extracted data we then prepared a simulation of an herbal bath. The heater in the bath provided a steady temperature of 35 °C. The samples were heated in the bath in erlenmeyers and vials. All the samples were being taken out of the herbal bath in predetermined time intervals and were analyzed with the SPME method (samples of the gas phase) or with the liquid/liquid extraction (samples of the liquid phase). The analysis was being taken in both seawater and distilled water. After that, the samples from the liquid phase had to be extracted with dichloromethane, vaporized and then analysed on GS-MS. The samples from the gas phase required no previous preparation. The analysis was being carried out on a gas chromatograph and was followed by an identification of compounds that were made during the process of chlorination. Results: With the experimental work, we proved the occurrence of side products that is produced in the water with the simultaneous use of the disinfection agent and herbal extract, in our case limonene. In all of our samples, taken during the different time periods, we identified 18 different compounds. Disinfection by-products were detected in liquid and gas phase, the liquid phase had more detected compounds. Disinfection by-products were identified in both sea and distilled water. During the chlorination, we identified different oxides, primary, secondary and tertiary products of adding chlorine and primary products of bromination in seawater. Discussion and conclusion: In the samples that were exposed to the addition of chlorine for a longer period, we identified more different compounds than in the samples that were exposed for a shorter period. In the samples that were being taken at a higher temperature, we proved the occurrence of oxides, which were not detected in samples taken at room temperature. In the samples of seawater, we identified the compounds with bromine that were not present in distilled water. In some samples, we identified the emergence of trihalometane.

Biofilms provide a protective environment for pathogens such as Campylobacter jejuni, the most prevalent foodborne pathogen, and biofilm formation can enhance bacterial survival in hostile environments. Adhesion of bacteria to the different materials of industrial surfaces is the first step in biofilm formation. Modulation of bacterial adhesion and biofilm formation thus represent important targets in alternative control strategies for reduction of pathogens in food-processing environments. With the high prevalence of C. jejuni and the lack of effective control measures, new control strategies are needed to block adhesion and biofilm formation on food contact surfaces in the food industry, with a focus here on natural antimicrobial phytochemicals. Plants remain a poorly recognized yet vast source of such antimicrobials. Valuable phytochemicals can be obtained directly from plant materials but also from agro-food by-products and waste materials. These materials represent a source of important plant bioactive phytochemicals that are effective for prevention of bacterial adhesion. In this review, we will focus on the anti-adhesion activities of phytochemicals targeted against C. jejuni, on the appropriate methodologies to determine anti-adhesion effects of phytochemicals, on the mechanisms of C. jejuni adhesion, and thus possible targets for reduction and control of this foodborne pathogen in food processing environments.

The influence of actively/passively encapsulated oleuropein on DPPC liposomes thermal and structural properties, and its antioxidant capacity against lipid peroxidation were investigated. Also, an oleuropein-rich olive leaf extract was encapsulated in soy phosphatidylcholine (PL-90 g) and incorporated in model and commercial drinks. Oleuropein induced a concentration-dependent broadening and splitting of the gel-to-liquid phase transition temperature. Fluorescence measurements revealed a fluidizing effect on liposomes below their gel-to-liquid phase transition temperature, and a higher lipid ordering above, especially to active encapsulation. Oleuropein also showed an antioxidant effect against lipid peroxidation in PL-90 g liposomes. PL-90 g Liposomes with olive leaf extract showed a mean diameter of 405 ± 4 nm and oleuropein encapsulation efficiency of 34% and delayed oleuropein degradation at pH 2.0 and 2.8 model drinks. In conclusion, greater effects were observed on the structure and fluidity of DPPC liposomes when oleuropein was actively encapsulated, while its incorporation into acidic foods in encapsulated form could enhance its stability.

Namen diplomske naloge je bil ovrednotiti protibakterijsko in protiadhezivno delovanje ekstraktov ajdovih in pirinih kalčkov z bakterijami vrst Staphylococcus aureus in Pseudomonas aeruginosa. Protibakterijsko delovanje ekstraktov ajdovih in pirinih kalčkov smo določili z metodo razredčevanja v mikrotitrski ploščici in z metodo difuzije. Ekstrakti ajdovih in pirinih kalčkov niso pokazali protibakterijskega delovanja pri nobeni metodi. Ekstrakti ajdovih kalčkov ne delujejo protibakterijsko do koncentracije 8,0 mg/mL, medtem ko ekstrakti pirinih kalčkov niso pokazali protibakterijske aktivnosti do koncentracije 1,57 mg/mL. Za določitev minimalne inhibitorne koncentracije (MIC) ekstraktov ajdovih in pirinih kalčkov bi bile potrebne dodatne raziskave npr. z uporabo večjih koncentracij le-teh ali drugačnih postopkov ekstrakcije. Protiadhezivno delovanje ekstraktov smo določali z metodo barvanja s kristal vijoličnim. Ekstrakti ajdovih kalčkov (0,5 in 0,1 MIC) so pri bakterijah vrste Staph. aureus povečali adhezijo, medtem ko sta ekstrakt ajdovih kalčkov (E2 pri 2,0 mg/mL) in ena od frakcij ekstrakta E2 (F4 pri 0,08 mg/mL) delovala protiadhezivno na bakterije vrste P. aeruginosa, Ekstrakt pirinih kalčkov pri 0,5 in 0,1 MIC ni imel protiadhezivnega delovanja na bakterije vrste Staph. aureus, medtem ko je pri bakterijah vrste P. aeruginosa pri 0,5 MIC adhezijo povečal. Rezultati kažejo, da bi bile smiselne nadaljnje podrobne raziskave o aktivnosti ekstraktov ajdovih kalčkov tako pri grampozitivnih kot pri gramnegativnih bakterijah. The purpose of the research was to determine the antibacterial and antiadhesive activity of buckwheat and spelt sprouts extracts against Staphylococcus aureus and Pseudomonas aeruginosa. The antibacterial activity of the extracts was determined by broth microdilution method and by agar diffusion method. The buckwheat extracts did not show any antibacterial activity up to 8,0 mg/mL and the spelt extract did not show any activity up to 1.57 mg/mL. More research is needed for minimal inhibitory concentration (MIC) determination with higher concentration of extracts or different extraction procedures. The antiadhesive activity of the extracts was determined by crystal violet staining method in a microtitre plate. The buckwheat sprouts extracts (0.5 and 0.1 MIC) increased the adhesion of Staph. aureus, but buckwheat sprouts extract (E2 at 2,0 mg/mL) and one of E2 factions (F4 at 0.08 mg/mL) decreased adhesion of P. aeruginosa. The spelt sprout extract did not show any antiadhesive activity on Staph. aureus at 0.5 and 0.1 MIC, furthermore it increased the adhesion of P. aeruginosa at 0.5 MIC. The results show that more detailed research is needed to determine the activity of buckwheat and spelt sprout extracts on gram-negative and gram-positive bacteria.

Pekoče paprike, bolj znane pod imenom čiliji, pridobivajo na svoji prepoznavnosti tako v Sloveniji kot po svetu. Ne samo, da jih vedno več uporabljamo kot dodatek k jedem, raziskovalci iz različnih področij tudi razkrivajo pozitivne učinke na zdravje ter na obstojnost živil tako s kemijskega kot mikrobiološkega vidika. V diplomskem delu smo se osredotočili na kvantifikacijo kapsaicinov v metanolnem ekstraktu plodov čilija Capsicum chinense, sorte 'Habanero'.in kakšen vpliv je na vsebnost kapsaicinoidov imel način sušenja plodov. Plodove čilija smo sušili na dva načina, po klasični metodi v domačem sušilniku, v drugem primeru pa z liofilizacijo. Suhi vzorci čilijev so vsebovali med 9,6 – 12,2 % vode. Po sušenju smo izvedli ekstrakcijo z metanolom ter v ekstraktih določili antioksidativni potencial in vsebnost kapsaicinoidov. Največjo vsebnost kapsaicina, dihidrokapsaicina in norhidrokapsaicina smo ugotovili v liofiliziranih in mletih vzorcih, sledijo liofilizirani vzorci ter klasično sušeni vzorci. Vsebnost homo kapsaicina in homodihidro kapsaicina je bila največja v klasično sušenih vzorcih čilija. Preračunano na stopnjo pekočnosti po Shovillovi lestvici – SHU (ang. Scoville Heat Units Scovillove enote pekočnosti) so najvišjo stopnjo dosegli liofilizirani im mleti vzorci s 129.091 ± 16.999 SHU/100 g suhe snovi (oziroma 6.325 ± 833 SHU/100g svežega vzorca), najnižjo pa klasično sušeni s 84.313 ± 9.026 SHU/100 g suhe snovi (oz. 3.963 ± 424 SHU/100 g svežega vzorca). Podoben trend smo ugotovili pri merjenju antioksidativnega potenciala ekstraktov. Te razlike v rezultatih lahko do neke mere pripišemo temperaturni razgradnji in oksidaciji kapsaicinoidov in antioksidantov, vendar je ključno vlogo imela priprava vzorcev pred ekstrakcijo. Hot peppers, also known as chilies, are becoming more and more popular in Slovenia and also in the whole world. Not only are chilies increasingly used as a spice, but researchers from various fields are also discovering their beneficial health effects. Various compounds from chilies have an impact on human health and also act as chemical and antimicrobial food preservatives. In this thesis, we have focused on the methanolic extract from chilies, in order to quantify capsaicinoids as a function of drying. We have compared the efficiency of different drying methods of Capsicum chinense cv. 'Habanero' chilly. We carried drying by means of the household dryer and on laboratory lyophilizer. Dried chilli samples had 9.6-12.2 % of water. After drying, we carried out methanol extraction. Methanol extracts were used to determine the antioxidative potential and contents of capsaicinoids. The highest content of capsaicin, dihydrocapsaicin, and norhydrocapsaicin was determined in lyophilized and grounded sample, followed by lyophilised and classically dried samples. On the contrary, the highest contents of homocapsaicin, and homohydrocapsaicin were found in classically dried samples. We have converted contents of capsaicinoids into Scoville Heat Units (SHU) and came to the conclusion that lyophilized and ground samples had the highest level of pungency: 129,091 ± 16,999 SHU per 100 g of dry weight (6,325 ± 833 SHU per 100 g of fresh weight). The lowest level was detected in traditionally dried samples: 84,313 ± 9,026 SHU per 100 g of dry weight (3.963 ± 424 SHU per 100g of fresh weight). We have noted a similar trend when we determined the antioxidative potential of the extracts. These differences could be the result of heat degradation of capsaicinoids and antioxidants to some degree, but the preparation of the samples before extraction had the key role.

Neurodegenerative diseases, namely Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis, Huntington’s disease, and multiple sclerosis are becoming one of the main health concerns due to the increasing aging of the world’s population. These diseases often share the same biological mechanisms, including neuroinflammation, oxidative stress, and/or protein fibrillation. Recently, there have been many studies published pointing out the possibilities to reduce and postpone the clinical manifestation of these deadly diseases through lifelong consumption of some crucial dietary substances, among which phytochemicals (e.g., polyphenols) and endogenous substances (e.g., acetyl-L-carnitine, coenzyme Q10, n-3 poysaturated fatty acids) showed the most promising results. Another important issue that has been pointed out recently is the availability of these substances to the central nervous system, where they have to be present in high enough concentrations in order to exhibit their neuroprotective properties. As so, such the aim of this review is to summarize the recent findings regarding neuroprotective substances, their mechanisms of action, as well as to point out therapeutic considerations, including their bioavailability and safety for humans.

Nevrodegenerativne bolezni prizadenejo živčevje, pojavijo pa se lahko zaradi različnih vzrokov. Eden od teh je proteinopatija. V različnih raziskavah so ugotavljali, ali lahko rastlinske ekstrakte uporabimo za zdravljenje nevrodegenerativnih bolezni. Spojine v rastlinskih ekstraktih imajo antioksidativne in nevroprotektivne lastnosti ter lahko učinkujejo proti proteinskim agregatom. Učinke so preverili na modelnih organizmih, kot so miši Mus musculus, vinske mušice Drosophilla melanogaster, kvasovke Saccharomyces cerevisiae, črvi Caenorhabditis elegans in celične linije, ki so kazali fenotip nevrodegenerativne bolezni. Pri S. cerevisiae so merili viabilnost celic, ki so bile izpostavljene ekstraktom opuncije Opuntia ficus-indica in rjave alge Padina pavonica. Pri D. melanogaster pa so ugotavljali, ali ekstrakti iz opuncije, rjave alge ter kurkumin podaljšajo življenjsko dobo ter, ali vplivajo na mobilnost vinskih mušic. V celični liniji nevroblastoma so merili, ali ekstrakt iz rastline Gastrodia elata prepreči celično smrt, ki so jo povzročali toksični agregati. Poleg tega so v raziskavah in vitro preverili preprečevanje nastanka toksičnih agregatov, ki so odgovorni za pojav bolezni. Ugotovili so, da nekateri rastlinski ekstrakti pozitivno vplivajo na viabilnost kvasovk, izboljšajo življenjsko dobo in mobilnost vinskih mušic ter preprečujejo celično smrt v celični liniji. Tudi in vitro nekateri ekstrakti dobro delujejo, saj se v njihovi prisotnosti zmanjša koncentracija toksičnih oligomerov ter poveča koncentracija netoksičnih monomerov in polimerov. Rastlinski ekstrakti dobro učinkujejo proti nevrodegenerativnim boleznim in imajo potencial za zdravljenje le-teh. Neurodegenerative diseases affect the nervous system and can occur due to various causes. One of these is proteinopathy. In various studies, it was determined whether plant extracts could be used to treat neurodegenerative diseases. Compounds in plant extracts have antioxidant and neuroprotective properties and may be effective against protein aggregates. The effects were examined on model organisms such as mice Mus musculus, fruit fly Drosophilla melanogaster, yeast Saccharomyces cerevisiae and worm Caenorhabditis elegans and cell line that showed fenotype of nevrodegenerative disease. For S. cerevisiae they measured viability of cells that were exposed to extracts from prickly pear Opuntia ficus-indica and brown alga Padina pavonica. In D. melanogaster they determined whether the extracts from prickly pear, brown alga and curcumin prolonged life expectancy and whether it can affect the mobility of fruit flies. In cell line of neuroblastoma they tested whether extract from Gastrodia elata can prevent cell death that is caused by toxic aggregates. They also checked the in vitro prevention of the formation of toxic aggregates that are responsible for the occurrence of disease. They found out that some plant extracts influence the yeast viability, improve lifespan and mobility of fruit flies and prevent cell death in cell line. Also in vitro the extracts worked well, as the concentration of toxic oligomers is reduced, and the concentration of non-toxic monomers and polymers is increased. Plant extracts have good effect against neurodegenerative diseases and have the potential to treat them.

Proučevali smo tvorbo heterocikličnih aromatskih aminov (HAA) ob različnih dodatkih na sol vezanega brinovega ekstrakta v goveje pleskavice po 4,5 minutnem pečenju na dvoploščnem žaru pri temperaturi 240 °C. Glede na dodatek brinovega ekstrakta in soli (NaCl) v maso za goveje pleskavice smo oblikovali enajst kombinacij oz. eksperimentalnih skupin (0/0 – negativna kontrola (brez NaCl in ekstrakta), 1,25/0 – 1,25 g NaCl, 1,30/0 – 1,3 g NaCl, 1,60/0 – 1,6 g NaCl, 0,75/0,50 – 0,75 g NaCl + 0,50 g ekstrakta, 0,65/0,65 – 0,65 g NaCl + 0,65 g ekstrakta, 0,25/1,00 – 0,25 g NaCl + 1 g ekstrakta, 0,80/0,80 – 0,8 g NaCl + 0,8 g ekstrakta, 0/1,25 – 1,25 g ekstrakta, 0/1,30 – 1,3 g ekstrakta, 0/1,60 – 1,6 g ekstrakta). Presno goveje meso, ki smo ga uporabili za izdelavo pleskavic je v 100 g v povprečju vsebovalo 73,85 ± 1,11 g vode, 22,32 ± 0,19 g beljakovin, 1,98 ± 0,31 g maščob in 1,44 ± 0,44 g soli ter 0,408 mmol kreatina in 0,036 mmol kreatinina. Z metodo Folin-Ciocalteu smo v ekstraktu brinovih jagod določili vsebnost skupnih fenolnih spojin 423,2 mg/l izraženo kot koncentracija galne kisline v mg na liter ekstrakta. Toplotno obdelane goveje pleskavice so v povprečju vsebovale 6,92 ± 4,51 μg skupnih HAA/kg, največ je bilo PhIP (1,96 g/kg), Glu-P-2 (1,74 g/kg), 4,8-DiMeIQx (0,92 g/kg), IQx (0,78 g/kg), MeIQx (0,54 g/kg), ostalih HAA, kot so harman, 7,8-DiMeIQx, norharman, AC in IQ se je tvorilo manj kot 0,5 g/kg (metoda LC-MS). Skupni dodatek soli oziroma ekstrakta brinovih jagod v koncentraciji 1,3 g/100 g presne mase poveča tvorbo skupnih HAA (in tudi nekaterih posameznih HAA, kot so MeIQx, PhIP in Glu-P-2). Z vidika zmanjšanja tvorbe HAA in senzorične sprejemljivosti je optimalen dodatek 0,75 g soli in 0,50 g brinovega ekstrakta, vezanega na sol (zmanjšanje tvorbe HAA pa ni statistično značilno). The aim of this study was to examine the formation of heterocyclic aromatic amines (HAA) in beef patties with different amounts of added juniper berries extract bound to the salt after grilling for 4,5 minutes on a two-plate grill at 240 °C. Regarding the amount of added juniper extract and salt (NaCl) to beef patties eleven combinations or experimental groups were formed (0/0 – negative control (without NaCl and extract), 1,25/0 – 1.25 g of NaCl, 1,30/0 – 1.3 g of NaCl, 1,60/0 – 1.6 g of NaCl, 0,75/0,50 – 0.75 g of NaCl + 0.50 g of extract, 0,65/0,65 – 0.65 g of NaCl + 0.65 g of extract, 0,25/1,00 – 0.25 g NaCl + 1 g of extract, 0,80/0,80 – 0.8 g NaCl + 0.8 g of extract, 0/1,25 – 1.25 g of extract, 0/1,30 – 1.3 g of extract, 0/1,60 – 1.6 g of extract). In average, raw beef used for patty production in 100 g contains 73.85 ± 1.11 g of water, 22.32 ± 0.19 g of protein, 1.98 ± 0.31 g of fat and 1.44 ± 0.44 g of NaCl as well as 0.408 mmol of creatine and 0.036 mmol of creatinine. Juniper berries extract contains 423.2 mg of total phenolic compounds/L (expressed as the concentration of galic acid in mg per litre of extract) analysed by Folin-Ciocalteu method. Grilled beef patties contained on average 6.92 ± 4.51 μg of total HAA/kg, with the highest amount of PhIP (1.96 g/kg), Glu-P-2 (1.74 g/kg), 4,8-DiMeIQx (0.92 g/kg), IQx (0.78 g/kg), MeIQx (0.54 g/kg), and other HAA, such as Harman, 7,8-DiMeIQx, Norharman, AC and IQ less than 0.5 g/kg (LC-MS method). A sum addition of salt and juniper berries extract at concentration of 1.3 g/100 g of raw patty mass increase the formation of total HAAs (as well as some individual HAA, such as MeIQx, PhIP and Glu-P-2). From the lower formation HAA and sensory acceptability point of view the most optimal was addition of 0.75 g of salt and 0.50 g of salt-bound juniper berries extract (statistically not significant).