SUMMARYProduction of biofuels from renewable feedstocks has captured considerable scientific attention since they could be used to supply energy and alternative fuels. Bioethanol is one of the most interesting biofuels due to its positive impact on the environment. Currently, it is mostly produced from sugar- and starch-containing raw materials. However, various available types of lignocellulosic biomass such as agricultural and forestry residues, and herbaceous energy crops could serve as feedstocks for the production of bioethanol, energy, heat and value-added chemicals. Lignocellulose is a complex mixture of carbohydrates that needs an efficient pretreatment to make accessible pathways to enzymes for the production of fermentable sugars, which after hydrolysis are fermented into ethanol. Despite technical and economic difficulties, renewable lignocellulosic raw materials represent low-cost feedstocks that do not compete with the food and feed chain, thereby stimulating the sustainability. Different bioprocess operational modes were developed for bioethanol production from renewable raw materials. Furthermore, alternative bioethanol separation and purification processes have also been intensively developed. This paper deals with recent trends in the bioethanol production as a fuel from different renewable raw materials as well as with its separation and purification processes.

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SummaryBiodiesel and biogas are two very important sources of renewable energy worldwide, and particularly in EU countries. While biodiesel is almost exclusively used as transportation fuel, biogas is mostly used for production of electricity and heat. The application of more sophisticated purification techniques in production of pure biomethane from biogas allows its delivery to natural gas grid and its subsequent use as transportation fuel. While biogas is produced mostly from waste materials (landfills, manure, sludge from wastewater treatment, agricultural waste), biodiesel in EU is mostly produced from rapeseed or other oil crops that are used as food. This raises the 'food or fuel' concerns. To mitigate this problem considerable efforts have been done to use non-food feedstock for biodiesel production. These include all kinds of waste oils and fats, but recently more attention has been devoted to production of microbial oils by cultivation of microorganisms that are able to accumulate high amounts of lipids in their biomass. Promising candidates for microbial lipids production can be found www.ftb.com.hrPlease note that this is an unedited version of the manuscript that has been accepted for publication. This version will undergo copyediting and typesetting before its final form for publication. We are providing this version as a service to our readers. The published version will differ from this one as a result of linguistic and technical corrections and layout editing.2 among different strains of filamentous fungi, yeast, bacteria and microalgae. Feedstocks of interest are agricultural waste rich in carbohydrates as well as different lignocellulosic raw materials where some technical issues have to be resolved. In this work, recovery and purification of biodiesel and biogas were also considered.

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The bioactive composition and cytotoxic and antioxidative/prooxidative effects of four medicinal plants: yarrow (Achillea millefolium L.), hawthorn (Crataegus oxyacantha L.), ground ivy (Glechoma hederacea L.), and olive (Olea europea L.) on human laryngeal carcinoma cell line (HEp2) were investigated. Water extracts of these plants obtained by infusion, maceration, and decoction were characterized for their polyphenol content and antioxidant capacity. Based on the extraction efficiency of polyphenols, the final extracts were obtained whose polyphenolic profile, polysaccharides, mineral content, and cytoprotective activities were determined. The overall highest content of polyphenols and antioxidant capacity was determined in hawthorn, followed by yarrow and ground ivy, and the lowest in olive leaves extract. Phytochemical screening revealed the presence of phenolic acids, as the most abundant bioactive compounds, followed by flavonoids, flavons, and flavonols. All examined medicinal plants reduced the cell viability and reactive oxygen species formation in a dose- and time-dependent manner. Ground ivy and yarrow containing a high content of phenolic acids and polysaccharides were more efficient to decrease the cell survival when compared to olive leaf and hawthorn. Experiments confirmed the importance of polyphenolic composition rather than content of investigated plants and revealed a relationship between the polyphenolic and polysaccharide contents and antioxidant/prooxidant characters of medicinal plants.

Pursuant to the tendencies of producing functional foods, attractive to a wide range of consumers, in this study chocolates enriched with freeze dried (FD) and concentrated (CE) nettle extracts were formulated, and their polyphenolic and antioxidant capacity stability evaluated during 12 months of storage. A simple aqueous extraction procedure of nettle was developed, and the defined extract evaluated for its cytotoxic and antioxidant/prooxidant activity on human colon cancer cell line (SW 480). An increase in total polyphenolic content, chlorogenic acid and flavonoid derivatives (originating from nettle extract) contents was achieved in enriched chocolates. Implementation of FD extract enabled higher increase of polyphenolic content in comparison to CE extract. During storage, fluctuations of polyphenolic content were observed, but the final bioactive parameters did not differ (or increased) from the initial ones. Nettle enriched chocolates exhibited more intense bitterness and astringency, while dark chocolates were preferred over milk and semisweet ones.