Arijana Bušić

Phytochemical Attributes of Four Conventionally Extracted Medicinal Plants and Cytotoxic Evaluation of Their Extracts on Human Laryngeal Carcinoma (HEp2) Cells

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.

Comparative evaluation of CO2 drying as an alternative drying technique of basil (Ocimum basilicum L.) — The effect on bioactive and sensory properties

In this study the potential of employing CO2 drying as an alternative to conventional drying techniques of basil was evaluated, with the aim of preservation of native bioactive and sensory properties of basil. For that purpose, optimal CO2 processing conditions were established and compared to air-dried and freeze dried basil samples. The contents of bioactive compounds (polyphenols, chlorophylls, ascorbic acid) and antioxidant capacity were determined spectrophotometrically and using high performance liquid chromatography (HPLC-PDA) analysis. Color analysis and essential oil content were also determined, while consumer evaluation of sensory properties was conducted using hedonic scale preference analysis. According to the obtained results, freeze drying was recognized as the most suitable technique for preservation of color, essential oil content, bioactive compounds and antioxidant capacity of basil. The essential oil content of basil ranged from 0.21 to 0.96%, and decreased upon prolongation of CO2 drying time. Among 4 identified phenolic acids (rosmarinic, chicoric, caftaric and caffeic), rosmarinic acid was the most abundant in all samples. Longer CO2 drying duration (4h) also exhibited the most detrimental effect on the polyphenolic compound content and antioxidant capacity of basil. The taste and appearance of CO2 dried basil were scored higher in comparison to air-dried basil, but further optimization of CO2 drying is needed to improve its aroma properties. Based on the obtained results, employing shorter CO2 drying time (2, 3h) and pressures of 80-100bar at 40°C might be a good alternative to freeze drying of basil.

Compositional evaluation of selected agro-industrial wastes as valuable sources for the recovery of complex carbohydrates

Re-utilization of various agro-industrial wastes is of growing importance from many aspects. Considering the variety and complexity of such materials, compositional data and compliant methodology is still undergoing many updates and improvements. Present study evaluated sugar beet pulp (SBP), walnut shell (WS), cocoa bean husk (CBH), onion peel (OP) and pea pods (PP) as potentially valuable materials for carbohydrate recovery. Macrocomponent analyses revealed carbohydrate fraction as the most abundant, dominating in dietary fibres. Upon complete acid hydrolysis of sample alcohol insoluble residues, developed procedures of high performance thin-layer chromatography (HPTLC) and high performance liquid chromatography (HPLC) coupled with 3-methyl-1-phenyl-2-pyrazolin-5-one pre-column derivatization (PMP-derivatization) were used for carbohydrate monomeric composition determination. HPTLC exhibited good qualitative features useful for multi-sample rapid analysis, while HPLC superior separation and quantification characteristics. Distinctive monomeric patterns were obtained among samples. OP, SBP and CBH, due to the high galacturonic acid content (20.81%, 13.96% and 6.90% dry matter basis, respectively), may be regarded as pectin sources, while WS and PP as materials abundant in xylan-rich hemicellulose (total xylan content 15.53%, 9.63% dry matter basis, respectively). Present study provides new and valuable compositional data for different plant residual materials and a reference for the application of established methodology.

Consumer acceptability of liquorice root (Glycyrrhiza glabra L.) as an alternative sweetener and correlation with its bioactive content and biological activity.

Abstract Consumer acceptability and sensory properties of liquorice root (Glycyrrhiza glabra L.) were evaluated. Quantitation of total polyphenolics and glycyrrhizic acid (GA), as well as the antioxidant capacity of liquorice extracts, was conducted and their biological effects (cytotoxic, antioxidative/pro-oxidative activity, lipid peroxidation on human laryngeal carcinoma cell line) compared to the ones of their predominant bioactive compound – GA. Conducted consumer survey revealed poor familiarity with liquorice (12.37% of correspondents), but willingness towards its use as an alternative sweetener (77.32% of consumers). Polyphenolic content of evaluated extracts ranged from 1018.18 to 1277.27 mg gallic acid equivalents (GAE)/l while GA content varied between 2179.53 and 2944.13 mg/l. The most pronounced cytotoxic effect (60%) and lipid peroxidation were exerted by treatment with the highest applied extract concentrations (10 mg/ml). Pure GA exhibited cytotoxic and pro-oxidative effects at concentrations of 0.12–0.6 mg/ml. Due to high GA content, coupled with its pronounced cytotoxic activity, the intake of liquorice root should be limited.

Formulating blackberry leaf mixtures for preparation of infusions with plant derived sources of sweeteners

Herbal mixtures composed of blackberry leaf and natural sweeteners (dried apples, prunes, figs, raisins, apricots, carrot and sweet potato, stevia leaves and liquorice root) were developed. Their nutritive and bioactive profile, biological activity and sensory properties were determined. Formulated mixtures exhibited lower total polyphenol content (259.09-350.00 mg GAE/L) when compared to plain blackberry leaf, but contained higher content of chlorogenic, ferulic, p-coumaric, rosmarinic acids and quercetin, as well as some macroelements (Ca, K, Mg) and microelements (Ba, Na). Stevia addition to formulated mixtures ensured higher polyphenolic content. Dried carrot exhibited the highest (0.988 g/g) and liquorice the lowest (0.087 g/g) content of total sugars but it contributed to the sweetness with 574.48 mg/L of glycyrrhizic acid derivatives. Plain blackberry leaf extract exhibited cytotoxic and antioxidative activity on human colon cancer cells. Formulated mixtures exhibited improved flavour profile and balanced sweetness in relation to plain blackberry leaf infusion.

Application of whey protein isolates and zein for the formulation of alginate-based delivery systems encapsulating Ganoderma lucidum polyphenols

Due to the rich phytochemical composition of the medicinal mushroom Ganoderma lucidum, especially its ß-glucan-based polysaccharides and triterpenes, but polyphenols, amino acids, and proteins as well, Ganoderma is often used in various nutraceutical and functional food products. Lately these products have been formulated with microencapsulated forms of active compounds in order to prevent their degradation after oral consumption and under processing conditions. The aim of this study was to characterize and encapsulate polyphenols from the aqueous extract of Ganoderma, using ionic gelation of alginate (A) and its combination with whey protein isolates (WPI) and zein (Z). The obtained hydrogel beads were scanned for physico-chemical and morphological properties, encapsulation efficiency of polyphenols, and their release kinetics in simulated gastrointestinal fluids. The addition of WPI to the alginate resulted in the reduction of the particle size and the spherical shape of the beads, while beads formulated with zein were characterized as larger, with irregular morphology. Encapsulation efficiency of total polyphenols has been determined as follows: 76.91% (A-WPI) < 83.91% (A) < 85.42% (A-Z). The most extended release of polyphenols in simulated gastrointestinal fluids has been achieved by employing WPI in the alginate delivery system. The implementation of additional coatings resulted in the enhanced properties of plain alginate carrier, where alginate-based hydrogels immobilizing Ganoderma polyphenols proved to be potential functional ingredients.

Antioxidants in Coffee

Abstract Coffee brew presents a rich source of bioactive compounds known to be powerful antioxidants. The present paper gives an overview of these antioxidants. Coffee provides a high content of chlorogenic acids and caffeine, as well as a significant content of nicotinic acid, trigonelline, tocopherols, cafestol, kahweol, and heterocyclic compounds. The quality of coffee used for the preparation of a beverage is related to the chemical composition of the roasted beans, which is affected by the chemical composition of the green beans and post-harvest processing conditions (drying, storage, roasting, and grinding). Although phenolic antioxidants, naturally occurring in coffee, are degraded during the roasting process, the antioxidant properties of roasted coffee can be maintained, or even enhanced, by the formation of compounds with antioxidant activity, such as Maillard reaction products. Because of their significant antioxidant properties, coffee by-products can also be used as functional ingredients or additives in the food industry.

The Potential of Combined Emulsification and Spray Drying Techniques for Encapsulation of Polyphenols from Rosemary (Rosmarinus officinalis L.) Leaves

SUMMARY The present study evaluates the potential of encapsulation of polyphenolic antioxidants from rosemary (Rosmarinus officinalis L.) leaves by combining emulsification and spray drying techniques. To stabilize the emulsions and prepare samples suitable for use in dry products, double emulsions encapsulating rosemary polyphenolic extract and containing polyglycerol polyricinoleate (4%), whey protein isolates (2 and 4%) as emulsifiers, and maltodextrins (MDE 10 and 21) as enhancing coatings were subjected to spray drying. The obtained results show insignificant (p>0.05) effect of used maltodextrin type and protein content on mean particle size of double emulsions containing rosemary polyphenols. Morphology analyses showed that double emulsions were successfully prepared, spherical microcapsules were obtained after spray drying of double emulsions and double emulsion form was still preserved after rehydration of spray-dried microcapsules. Regardless of used maltodextrins, significantly (p>0.05) higher encapsulation efficiencies (EE) of total polyphenols (39.57 and 42.83%) in rehydrated samples were achieved when higher protein content (4% whey protein isolate) was used, indicating the major impact of protein content on EE of rosemary polyphenols. Also, using HPLC analysis, rosmarinic and caffeic acids, apigenin and luteolin derivatives were detected among specific polyphenols, where rosmarinic acid had notable encapsulation efficiency ranging from 62.15 to 67.43%. In this way, the obtained microcapsules encapsulating rosemary polyphenols could be easily blended with various dry mixtures, and serve for delivery in different functional products.

Bioethanol Production from Renewable Raw Materials and its Separation and Purification: a Review

SUMMARY Production 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.

Structuring new alginate network aimed for delivery of dandelion (Taraxacum officinale L.) polyphenols using ionic gelation and new filler materials

Alginate hydrogels are often used for immobilization of plant-derived bioactive compounds by fast and simple ionic gelation technique. However, the structure of alginate gel network is very porous and mostly result with high-diffusion rates of encapsulated compound, what limits its application as delivery vehicle. In order to prevent losses of bioactives and prepare efficient encapsulation systems, the aim of this study was to evaluate a potential of new natural fillers, cocoa powder (CP) and carob (C) for structuring alginate network aimed for encapsulation of aqueous dandelion (Taraxacum officinale L.) leaf extract using ionic gelation. Whey protein isolates served as a standard filler. The influence of different concentrations of gelling medium (2% and 3% calcium chloride) on encapsulation properties of alginate systems was also evaluated. Calcium concentration affected morphological properties (more acceptable when using 3% CaCl2), while textural properties and encapsulation efficiency of polyphenols and retained antioxidant capacity were more influenced by selected delivery materials. Alginate-whey protein isolates beads were scored with the highest loading capacity of polyphenols (>93%), while newly formulated binary mixtures (alginate-cocoa powder and alginate-carob) also enabled highly efficient entrapment of polyphenols (>88%). The slowest release of polyphenols in simulated gastrointestinal fluids were obtained when alginate was combined with CP and C, where system alginate-cocoa powder prepared with lower concentration of calcium chloride (2% CaCl2) enabled the most extended release of total polyphenols and hydroxycinnamic acids. Obtained results strongly justified implementation of new plant-derived functional fillers (cocoa powder and carob) for encapsulation purposes and opened new directions for designing of binary carriers.