Konzumacija svježih citrusa, ali i njihova prerada generiraju nusproizvode, kao što su kora, sjemenke, pulpa, kao i otpadne vode. Cilj ovog istraživanja je valorizacija agroindustrijskih nusproizvoda ...(kore citrusa) kao vrijedne sirovine za ekstrakciju polifenola primjenom inovativne netermalne metode ekstrakcije sa zelenim otapalom (voda). U ekstraktima je kvantificirano i identificirano ukupno šest fenolnih spojeva. Pri tome je promatran utjecaj vremena (od 5 do 15 min), frekvencije (od 40 do 100 Hz) i omjera kapljevito/kruto (od 200 do 400 ml g−1) na efikasnost procesa ekstrakcije (iskorištenje) i udio dominantnih fenolnih spojeva (hesperidina i narirutina). Uz pomoć metode odzivnih površina definirani su optimalni parametri promatranog procesa ekstrakcije za svaki od istraživanih odziva, i to za iskorištenje (285,93 ml g−1, 73,38 Hz i 14,84 min), za hesperidin (366,19 ml g−1, 97,56 Hz i 5,1 min) te za narirutin (200 ml g−1, 70 Hz i 15 min). Ekstrakcija potpomognuta visokonaponskim električnim pražnjenjem (HVED ekstrakcija) pokazala se pogodnom za ekstrakciju fenolnih spojeva, pri čemu je izbjegnuta uporaba organskih otapala.
Viola odorata Aćimović, Milica; Vidović, Senka; Banožić, Marija ...
Croatian journal of food science and technology,
12/2021, Volume:
13, Issue:
2
Journal Article, Paper
Peer reviewed
Open access
This study aimed at examining the effect of supercritical carbon dioxide (ScCO2) extraction on the subsequent extraction of the Viola odorata polar bioactive components. The raw material was firs ...submitted to ScCO2 extraction for the extraction of the lipophilic fraction. Then the exhausted raw material was subjected to ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) in order to extract the polar components. ScCO2 extraction was performed under the pressure of 300 bar and at a temperature of 40 °C for 4 hours. In order to see the effect of ScCO2, the UAE and MAE (50% aqueous ethanol solution as solvent) were conducted on both exhausted (residue-after the ScCO2) and unexploited raw materials. Also, the impact of the various UAE and MAE conditions was tested. The UAE was conducted on two different temperatures (40 and 50 °C) at the constant extraction time (40 and 20 min). MAE was conducted on two different extraction powers (470 and 800 W) and at the constant extraction time (10 min). The results were focused on the content of total phenols, total flavonoids and antioxidant activity of the obtained extracts. The yield during the ScCO2 process was 1.43% (w/w). It was noted that the extracts obtained by applying UAE and MAE after the ScCO2 were noticeably richer in the content of total phenols. UAE conditions of 40 °C and 20 min showed the highest yield of total phenols, recording 70.38 mg GAE/g DE, while the MAE at the power of 470 W achieved 11.89% higher yield of polyphenols in residue extracts. The antioxidant activity has also been in correlation with the concentration of polyphenols.
Display omitted
•Tobacco waste – material which contain important active compounds.•With novel extraction techniques considerable amount of extracted active compound can be achieved.•Extracted ...compounds can be implemented into new products.•After extraction of some bioactive compounds, tobacco waste becomes more suitable for other application.
Acting as the one of the main non-food crops, tobacco plays an important role in agriculture all over the world. Tobacco processing industries generate a huge volume of tobacco waste as by-product which is usually discarded due to its nicotine content, and only small part of it is recycled. Recycled waste is used for producing low value tobacco paper, named reconstituted tobacco, which causes waste of abundant bioactive compounds with antioxidant, anti-inflammatory, antifungal properties. This review summaries the last knowledge about extraction of bioactive compounds from tobacco waste and introduces principles of new, most applied extraction techniques, such as ultrasound-assisted extraction, supercritical CO2 extraction and microwave-assisted extraction. Based on comparison of these techniques, this review points out that extraction of bioactive compounds from tobacco waste is new opportunity for this type of waste and its contribution to sustainable waste and resource management. What is more, extraction of bioactive compounds can be effective at two levels. Firstly, extracted compounds can be implemented into new products. Secondly, after extraction of certain bioactive compounds, tobacco waste becomes more suitable for some other application or disposal.
Carbohydrates are important compounds in natural products where they primarily serve as a source of energy, but they have important secondary roles as precursors of aroma or bioactive compounds. They ...are present in fresh and dried (cured) tobacco leaves as well. The sugar content of tobacco depends on the tobacco variety, harvesting, and primarily on the curing conditions (temperature, time and moisture). If the process of curing employs high temperatures (flue-curing and sun-curing), final sugar content is high. In contrast, when air curing has a lower temperature, at the end of the process, sugar level is low. Beside simple sugars, other carbohydrates reported in tobacco are oligosaccharides, cellulose, starch, and pectin. Degradation of polysaccharides results in a higher yield of simple sugars, but at the same time reduces sugars oxidization and transfer into carbon dioxide and water. Loss of sugar producers will compensate with added sugars, to cover undesirable aroma properties and achieve a better, pleasant taste during smoking. However, tobacco carbohydrates can be precursors for many harmful compounds, including formaldehyde and 5-hydroxymethylfurfural. Keeping in mind that added sugars in tobacco production are unavoidable, it is important to understand all changes in carbohydrates from harvesting to consuming in order to achieve better product properties and avoid the formation of harmful compounds. This review summarizes current knowledge about tobacco carbohydrates, including changes during processing with special focus on carbohydrates as precursors of harmful compounds during smoking.
This is the first study on ultrasound-assisted extraction (UAE) of bioactive compounds from different types of tobacco industry wastes (scrap, dust, and midrib). The obtained results were compared ...with starting raw material (tobacco leaves) to see the changes in bioactive compounds during tobacco processing. Results suggested that tobacco waste extracts possess antioxidant activity and considerable amounts of targeted bioactive compounds (phenolics and solanesol). The content of chlorogenic acid varied between 3.64 and 804.2 μg/mL, caffeic acid between 2.34 and 10.8 μg/mL, rutin between 11.56 and 93.7 μg/mL, and solanesol between 294.9 and 598.9 μg/mL for waste and leaf extracts, respectively. There were noticeable differences between bioactive compounds content and antioxidant activity in extracts related to applied UAE conditions and the used type of tobacco waste. Results show that optimal UAE parameters obtained by response surface methodology (RSM) were different for each type of material, so process optimization proved to be necessary. Considering that tobacco waste is mostly discarded or not effectively utilized, the results clearly show that tobacco waste could be used as a potential source of some bioactive compounds.
The content of bioactive compounds in four brown and one red algae from the Adriatic Sea (
,
,
and
) is explored. The efficiency of two different extraction methods viz. ultrasound-assisted ...extraction (UAE) and matrix solid-phase dispersion (MSPD) to obtain the extracts rich in phenolic compounds was compared. The effect of the extraction solvent to modulate the phenolic profile was assessed. In general, the mixture ethanol/water in an isovolumetric proportion showed the best results. The total phenolic content (TPC) and antioxidant activity (AA), as well as the individual polyphenolic profile, were evaluated for five target algae. TPC values ranged between 0.2 mg GAE/g (for
) and 38 mg GAE/g (for
). Regarding the quantification of individual polyphenols by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, the presence of a high number of hydroxybenzoic acid derivatives (mainly of 3- and 4-hydroxybenzoic acids) in all species was noted. In
their concentrations reached up to 500 mg/kg. IC
values (ABTS assay) ranged between 44 mg/L (for
) and 11,040 mg/L (for
). This work contributes to the in-depth characterization of these little-explored algae, showing their potential as a natural source of phenolic compounds.
Display omitted
•Tobacco waste – material which contain important active compounds.•Striking differences between tobacco waste and leaves.•With SWE a considerable amount of extracted active compound ...can be achieved.•Production of some unwanted compounds can be avoided with proper optimization of SWE process.
Three fraction of tobacco waste (scrap, midrib and dust) were subjected to subcritical water in a wide temperature range (150–250 °C), using solvent-solid ratio (10–30 mL/g) for periods from 5 to 25 min in a batch reactor and compared with tobacco leaves to determine the changes in content of compounds during tobacco processing. Optimal extraction conditions were established using RSM. Depending on applied extraction conditions as well as waste fraction, different concentrations of active compounds were determined. Tobacco waste extracts were characterized with high level of nicotine from 0.907 to 4.610%, and considerable amounts of 3,4 DHBA from 0.118 to 1.249%, chlorogenic acid from 0.033 to 0.507% and rutin up to 0.874%. Moreover, in all extracts some tobacco specific compounds were detected, namely nicotinic acid 0.087-0.846% and nicotinamide 0.095-0.400% as a product of nicotine hydrothermal degradation. At higher temperatures the presence of 5-HMF, furfural and 5-MF was detected.
With globalization, growing popularization and changes in dietary habits where more processed food is consumed, a generation of food wastes and by-products has increased. Under-exploitation of ...by-products and waste leads to finance losses and environmental pollution although most of the waste are a rich source of bioactive compounds. Using spray drying process, extracted bioactive compounds from food wastes and by-products can be transferred into powder form, and returned to the food chain. Spray drying technique showed to be the most convenient, energy efficient and time-saving process, where a liquid is directly transformed into stable powder, which can be stored for a prolonged time or easily incorporated into other products. This review article focuses on the application of processing parameters of spray drying with specific emphasis on the production of dry extracts of food waste and their influence on powder properties. Research gaps and challenges along with possible applications are also discussed.
The particles from the gas-saturated solutions (PGSS) process was employed to micronize brown algae pigments separated by different extraction techniques. The particle formation of pigments with a ...coating material, polyethylene glycol (PEG), was carried out by the PGSS process using supercritical CO2. Environmental scanning electron microscopy (ESEM) and Fourier-transform infrared spectroscopy (FTIR) were performed to characterize the produced particles, while encapsulation efficiency was determined using spectrophotometric methods. The physical properties of obtained microparticles were also determined. The PGSS process enabled a high encapsulation yield in the range from 61.60 to 73.73%, and high encapsulation efficiency in terms of chlorophyll a, chlorophyll b, and carotenoid content. The release of CO2 during the PGSS process gave the microparticles their characteristic open and porous form, and enhanced the solubility and flow properties at the same time.
This study aimed to investigate the effect of four green extraction techniques (ultrasound-assisted extraction, UAE; supercritical fluid extraction, SFE; subcritical water extraction, SWE; and ...extraction using deep eutectic solvents, DES) on the extraction of targeted flavonoids from edible feijoa flowers. The bioactive components in the obtained extracts were quantified by High-Performance Liquid Chromatography-Photodiode Array Detector (HPLC-PDA). Moreover, total polyphenol content and antioxidant activity by DPPH
, ABTS
, FRAP, and CUPRAC assays were investigated. UAE generally gave the highest yields for isoquercitrin and quercetin content (18.36-25.33 and 10.86-16.13 µg/g), while DES extraction with choline chloride:lactic acid (1:2) and H
O content of 50% gave the highest yield of chrysanthemin (90.81 µg/g). The highest yield of flavone (12.69 mg/g) was obtained with supercritical CO
at 300 bar. Finally, UAE gave the highest total polyphenol content (ca. 64 mg GAE/g) and antioxidant activity at 70 °C during 30 min with 40% (0.84 mmol TEAC/g and 2.25 mmol Fe
/g, for ABTS
and CUPRAC, respectively) and 60% ethanol-water solution (0.49 mmol TEAC/g and 2.09 mmol Fe
/g, for DPPH
and FRAP, respectively). The eco-friendly extraction techniques resulted in selective methods capable of extracting targeted bioactive compounds from edible feijoa flowers.
PDF
