Source Of Several Bioactive Compounds Research Articles

Short-Chain Fructooligosaccharide Synthesis from Sugarcane Syrup with Commercial Enzyme Preparations and Some Physical and Antioxidation Properties of the Syrup and Syrup Powder.

Short-chain fructooligosaccharides (sc-FOS) are prebiotics beneficial to human health, which can be synthesized from raw material containing a high sucrose content. Sugarcane syrup (SS) without molasses removal contains sucrose as a major sugar and is a rich source of several bioactive compounds. The aim of this study is to investigate factors affecting sc-FOS synthesis from SS using commercial enzyme preparations containing fructosyltransferase activity as biocatalysts. sc-FOS content increased significantly as the sucrose concentration of SS in the reaction mixture increased up to 40% (w/v). Changes in carbohydrate compositions during the transfructosylating reaction of a pure sucrose solution and SS prepared from the two sugarcane cultivars Khon Kaen 3 and Suphanburi 50, catalyzed by Pectinex Ultra SP-L and Viscozyme L, showed similar profiles. Both enzymes showed a high ability to transfer fructosyl moieties to produce sc-FOS and a plateau of the total sc-FOS concentration was observed after 4 h of reaction time. For the pure sucrose solution and SS (Suphanburi 50), Viscozyme showed a superior ability to convert sucrose to Pectinex, with a higher sc-FOS yield (g FOS/100 g of initial sucrose), GF2 or 1-kestose yield (g GF2/g of initial sucrose) and GF3 or nystose yield (g GF3/g of initial sucrose). sc-FOS syrup (FOS SS) and the foam-mat-dried syrup powder prepared from SS and FOS SS, respectively, contained a high total phenolic content and possessed higher antioxidant activities than those prepared from pure sucrose, but contained lower calories.

Anti-Hypercholesterolemia Effects of Edible Seaweed Extracts and Metabolomic Changes in Hep-G2 and Caco-2 Cell Lines.

Hypercholesterolemia is a major risk for the development of cardiovascular diseases (CVDs), the main cause of mortality worldwide, and it is characterized by high levels of circulating cholesterol. The drugs currently available for hypercholesterolemia control have several side effects, so it is necessary to develop new effective and safer therapies. Seaweeds serve as sources of several bioactive compounds with claimed beneficial effects. Eisenia bicyclis (Aramé) and Porphyra tenera (Nori) are edible seaweeds that were previously recognized as rich in bioactive compounds. In the present study, we aim to evaluate the anti-hypercholesterolemia effect of these two seaweed extracts and their health potential. Both extracts, but more efficiently Aramé extract, have liver 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) inhibitory activity as well as the capability to reduce approximately 30% of cholesterol permeation through human Caco-2 cells by simulating the intestinal lining, which is a target for hypercholesterolemia treatments. An untargeted metabolomic assay on human intestinal Caco-2 and liver Hep-G2 cell lines exposed to Aramé and Nori extracts revealed changes in the cells' metabolism, indicating the extracts' health beneficial effects. The metabolic pathways affected by exposure to both extracts were associated with lipid metabolism, such as phospholipids, and fatty acid metabolism, amino acid pathways, cofactors, vitamins, and cellular respiration metabolism. The effects were more profound in Aramé-treated cells, but they were also observed in Nori-exposed cells. The metabolite modifications were associated with the protection against CVDs and other diseases and to the improvement of the cells' oxidative stress tolerance. The results obtained for the anti-hypercholesterolemia properties, in addition to the revelation of the positive impact on cell metabolism, offer an important contribution for further evaluation of these seaweed extracts as functional foods or for CVD prevention.

Avocado oil alleviates non-alcoholic fatty liver disease by improving mitochondrial function, oxidative stress and inflammation in rats fed a high fat-High fructose diet.

Non-alcoholic fatty liver disease (NAFLD) is characterized by lipid accumulation in hepatocytes, and in advanced stages, by inflammation and fibrosis. Excessive ROS production due to mitochondrial dysfunction contributes to NAFLD development, making the decrease in mitochondrial ROS production an emerging target to alleviate NAFLD. Previously, we have shown that avocado oil, a source of several bioactive compounds with antioxidant effects, decreases oxidative stress by improving the function of the mitochondrial electron transport chain (ETC) and decreasing ROS levels in mitochondria of diabetic and hypertensive rats. Therefore, we tested in this work whether avocado oil alleviates NAFLD by attenuating mitochondrial dysfunction, oxidative stress and inflammation. NAFLD was induced in rats by a high fat-high fructose (HF) diet administered for six (HF6) or twelve (HF12) weeks. Hepatic steatosis, hypertrophy and inflammation were detected in both the HF6 and HF12 groups. Hyperglycemia was observed only in the HF12 group. The HF6 and HF12 groups displayed dyslipidemia, impairments in mitochondrial respiration, complex III activity, and electron transfer in cytochromes in the complex III. This led to an increase in the levels of ROS and lipid peroxidation. The substitution of the HF6 diet by standard chow and avocado oil for 6weeks (HF6+AVO + D), or supplementation of the HF12 diet with avocado oil (HF12 + AVO), ameliorated NAFLD, hyperglycemia, dyslipidemia, and counteracted mitochondrial dysfunctions and oxidative stress. The substitution of the HF6 diet by standard chow without avocado oil did not correct many of these abnormalities, confirming that the removal of the HF diet is not enough to counteract NAFLD and mitochondrial dysfunction. In summary, avocado oil decreases NAFLD by improving mitochondrial function, oxidative stress, and inflammation.

Bioactive Compounds and Antioxidant Activity from Spent Coffee Grounds as a Powerful Approach for Its Valorization.

Coffee is one of the world's most popular beverages, and its consumption generates copious amounts of waste. The most relevant by-product of the coffee industry is the spent coffee grounds, with 6 million tons being produced worldwide per year. Although generally treated as waste, spent coffee grounds are a rich source of several bioactive compounds with applications in diverse industrial fields. The present work aimed at the analysis of spent coffee grounds from different geographical origins (Guatemala, Colombia, Brazil, Timor, and Ethiopia) for the identification of bioactive compounds with industrial interest. For this purpose, the identification and quantification of the bioactive compounds responsible for the antioxidant activity attributed to the spent coffee grounds were attempted using miniaturized solid-phase extraction (µ-SPEed), combined with ultrahigh-performance liquid chromatography with photodiode array detection (UHPLC-PDA). After validation of the µ-SPEed/UHPLC-PDA method, this allowed us to conclude that caffeine and 5-caffeoylquinic acid (5-CQA) are the most abundant bioactive compounds in all samples studied. The total phenolic content (TPC) and antioxidant activity are highest in Brazilian samples. The results obtained show that spent coffee grounds are a rich source of bioactive compounds, supporting its bioprospection based on the circular economy concept closing the loop of the coffee value chain, toward the valorization of coffee by-products.

Aqueous Extracts of Fish Roe as a Source of Several Bioactive Compounds

Regular consumption of seafood and, in particular, fish has been associated with important health benefits. A fish product that has been increasingly included in the human nutrition is roe. Despite its nutritional value has been established (fatty acid profile and protein content), the knowledge of the composition of its aqueous extracts is still limited. This work describes the bioactive compounds profile in the roe-derived aqueous extracts of three different marine species (sardine, horse mackerel and sea bass) using a method based on liquid chromatography coupled to high-resolution mass spectrometry with an electrospray ionisation source (LC-ESI/HRMS). The presence of substances with well-known nutritional and functional properties (e.g., antioxidant and anti-inflammatory properties) was demonstrated, namely essential amino acids (e.g., taurine), peptides (e.g., anserine and carnosine), B-group vitamins (e.g., nicotinamide) and gadusol. Therefore, roe-derived aqueous extracts are excellent sources of bioactive compounds and may be used as a font of functional components for several medical and veterinary applications.

Chemical Composition, Antifungal, Antioxidant and Cytotoxic Potential of Apium graveolens L. (Celery) Leaves Essential Oil Collected from Nainital, Uttarakhand

Essential oils (EOs) extracted from aromatic plants are a potential source of several bioactive compounds. In the present study, hydro-distillation of Apium graveolens essential oil (AG-EO) was carried out and its chemical constituents were analyzed using Gas Chromatography (GC) and Gas Chromatography-Mass spectrometry (GC/MS) followed by examination of its antifungal, antioxidant, and cytotoxic potential against human breast cancer cells, MDA-MB-231. Analysis of EO resulted in the identification of nineteen (19) compounds majorly in 1,2-diphenyl-1,2-ethanediol (65.2%), 3-butyl phthalide (9.1%), limonene (6.4%), 1,1-dimethyl-1,2,3,5,7,8,9,9a-octahydro-benzocyclohepten-6-one (5.6%). Further, antifungal activity of A. graveolens EO (AG-EO) against three soil borne phytopathogenic fungal strains namely Fusarium oxysporum, Curvularia lunata, and Sclerotinia sclerotiorum showed significant mycelial growth inhibition at a concentration of 500 μg/mL with IC50 value ranging between 966-220.76 μg/mL. The antioxidant potential of EO was evaluated using dedicated spectrophotometric assays such as FRAP and DPPH. Results revealed the free radical scavenging potential of AG-EO with the value of 7.71±0.04 mM AAE/100g (for DPPH assay) and 8.31±0.03 mM AAE/100g (for FRAP assay). Additionally, the percentage of cell survival of MDA-MD-231 human breast cancer cells after treatment with EO was about 68% at 24h showing the cytotoxic effect of AG-EO against breast cancer cells whereas for non-malignant control HEK 293T cells it was about 83%. The present study indicated that the antioxidant, antifungal, and cytotoxic potential of AG-EO, a natural source of bioactive compounds, could be employed in the food, pharmaceuticals, agriculture, and cosmetics industries. However, further evaluations on animal models and clinical studies are warranted.

Chemical characterisation by UPLC-Q-ToF-MS/MS and antibacterial potential of Coffea arabica L. leaves: A coffee by-product.

Coffea arabica L. leaves are considered a by-product of the coffee industry however they are sources of several bioactive compounds. This study aimed to evaluate the chemical composition and the in vitro antibacterial activity of the lyophilised ethanol extract of arabica coffee leaves (EE-CaL). The chemical characterisation of EE-CaL was performed using ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UPLC-Q-ToF-MS/MS). The in vitro antibacterial effect of EE-CaL was evaluated using the broth microdilution method and the adapted drop plate agar method to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), respectively. The chemical analysis of EE-CaL revealed the presence of compounds from the alkaloid class, such as trigonelline and caffeine, in addition to the phenolic compounds such as quinic acid, 5-caffeoylquinic acid, caffeic acid-O-hexoside, mangiferin, (epi)catechin, (epi)catechin monoglucoside and procyanidin trimer. Regarding the antibacterial potential, EE-CaL was active against Gram-positive and Gram-negative bacteria, being more effective against Escherichia coli (ATCC 25922) (MIC = 2500 μg/mL and bactericidal effect). The results of this research suggest that coffee leaves, a by-product, possess compounds with antibacterial properties. Thus, further studies with coffee leaf extracts must be carried out to relate the compounds present in the extract with the antibacterial activity and find the mechanisms of action of this extract against bacteria.

Modulatory Properties of Food and Nutraceutical Components Targeting NLRP3 Inflammasome Activation.

Inflammasomes are key intracellular multimeric proteins able to initiate the cellular inflammatory signaling pathway. NLRP3 inflammasome represents one of the main protein complexes involved in the development of inflammatory events, and its activity has been largely demonstrated to be connected with inflammatory or autoinflammatory disorders, including diabetes, gouty arthritis, liver fibrosis, Alzheimer’s disease, respiratory syndromes, atherosclerosis, and cancer initiation. In recent years, it has been demonstrated how dietary intake and nutritional status represent important environmental elements that can modulate metabolic inflammation, since food matrices are an important source of several bioactive compounds. In this review, an updated status of knowledge regarding food bioactive compounds as NLRP3 inflammasome modulators is discussed. Several chemical classes, namely polyphenols, organosulfurs, terpenes, fatty acids, proteins, amino acids, saponins, sterols, polysaccharides, carotenoids, vitamins, and probiotics, have been shown to possess NLRP3 inflammasome-modulating activity through in vitro and in vivo assays, mainly demonstrating an anti-NLRP3 inflammasome activity. Plant foods are particularly rich in important bioactive compounds, each of them can have different effects on the pathway of inflammatory response, confirming the importance of the nutritional pattern (food model) as a whole rather than any single nutrient or functional compound.

Estimation of bioactive potential of culturable bacterial endophytes from Coleus

Endophytic microflora is source of several bioactive compounds. Endophytes isolated from Coleus species are yet to be fully explored for their bioactive potential. In this study, bacterial endophytes were isolated from three different species of Coleus. Isolated endophytes were characterized by using Gram staining and by sequencing 16S rRNA region. Further, solvents with different polarities were used to prepare extracts which were used for assessment of different bio-activities including in vitro cytotoxicity, anti-microbial and anti-oxidant activities. Also, the pure endophytic bacterial cultures were evaluated for their antiphytopathogen potential as well as indole-3-acetic acid (IAA) and protease production. Advanced studies on the endophytes with promising activities may lead to the isolation of novel natural products for drugs as well as in industrial and agricultural applications.

Antifungal, Antibacterial, and Cytotoxic Activities of Silver Nanoparticles Synthesized from Aqueous Extracts of Mace-Arils of Myristica fragrans.

In the present study, mace-mediated silver nanoparticles (mace-AgNPs) were synthesized, characterized, and evaluated against an array of pathogenic microorganisms. Mace, the arils of Myristica fragrans, are a rich source of several bioactive compounds, including polyphenols and aromatic compounds. During nano synthesis, the bioactive compounds in mace aqueous extracts serve as excellent bio reductants, stabilizers, and capping agents. The UV-VIS spectroscopy of the synthesized NPs showed an intense and broad SPR absorption peak at 456 nm. Dynamic light scattering (DLS) analysis showed the size with a Z average of 50 nm, while transmission electron microscopy (TEM) studies depicted the round shape and small size of the NPs, which ranged between 5–28 nm. The peaks related to important functional groups, such as phenols, alcohols, carbonyl groups, amides, alkanes and alkenes, were obtained on a Fourier-transform infrared spectroscopy (FTIR) spectrum. The peak at 3 keV on the energy dispersive X-ray spectrum (EDX) validated the presence of silver (Ag). Mace-silver nanoparticles exhibited potent antifungal and antibacterial activity against several pathogenic microorganisms. Additionally, the synthesized mace-AgNPs displayed an excellent cytotoxic effect against the human cervical cancer cell line. The mace-AgNPs demonstrated robust antibacterial, antifungal, and cytotoxic activity, indicating that the mace-AgNPs might be used in the agrochemical industry, pharmaceutical industry, and biomedical applications. However, future studies to understand its mode of action are needed.

An Investigation on Biological Efficacies of Fruits and Leaves of Ficus auriculata (Timilo) from Kanchanpur District, Nepal

Ficus auriculata is a native Asian plant found in the temperate, tropical and subtropical regions and has been commonly used in traditional medicine and as fodder in animal husbandry. The comparative antibacterial and antioxidant efficacies of leaves and fruits have been studied using their hexane, chloroform, ethyl acetate and methanol extracts. Phytochemical screening exhibited the presence of important secondary metabolites like alkaloids, carbohydrates, glycosides, flavonoids and tannins. Antibacterial activities of fruit and leaf extracts in different concentrations were studied against E. coli, S. aureus and S. typhi by agar well diffusion method. The highest inhibition was found to be in 1% methanol extracts of leaves and fruits with a zone of inhibition (ZOI) ± 16 mm against S. aureus followed by E. coli and S. typhi with ZOI ±14 mm. The crude and 50% extracts of various solvents of both fruits and leaves were found to be ineffective against bacteria. These results reveal that there is a significant antibacterial activity in methanol extract of both fruit and leaves, against gram-positive and gram-negative bacteria. The antioxidant activities of methanol extracts of fruits and leaves were studied by DPPH radical scavenging assay. The IC50 values of methanol extract of leaves and fruit for DPPH radical scavenging assay were found to be 114.84 μg/mL and 78.28 μg/mL, respectively. These results reveal that methanol fruit extract exhibits better antioxidant activity as compared to the leaves. The result of this investigation has revealed the applicability of this plant as a potential source of several bioactive compounds for the discovery of new and efficacious drugs in days to come.

Pink pressure: beetroot (Beta vulgaris rubra) as a possible novel medical therapy for chronic kidney disease

Chronic kidney disease (CKD) manifests with systemic inflammation, oxidative stress, and gut dysbiosis, resulting in metabolic disorders and elevated rates of cardiovascular disease-associated death. These all correlate with a high economic cost to healthcare systems. Growing evidence indicates that diet is an indispensable ally in the prevention and management of CKD and its complications. In this context, the root vegetable beetroot (Beta vulgaris rubra) deserves special attention because it is a source of several bioactive compounds, such as nitrate, betaine, and betalain, and has shown beneficial effects in CKD, including reduction of blood pressure, anti-inflammatory effects, and antioxidant actions by scavenging radical oxidative species, as observed in preclinical studies. Beetroot consumption as a possible therapeutic strategy to improve the clinical treatment of patients with CKD and future directions for clinical studies are addressed in this narrative review.

Comparative Study Regarding the Chemical Composition and Biological Activity of Pine (Pinus nigra and P. sylvestris) Bark Extracts.

The bark resulted after the industrial processing of wood represents a byproduct of the forestry industry, used in many suboptimal ways, being considered a natural waste. Currently, it has been highlighted that the bark of different woody plants may be an important source of several bioactive compounds, with various beneficial biological functions. The aim of this study is to evaluate and compare the chemical composition and biological activities of two different pine species (Pinus nigra and Pinus sylvestris) bark extracts. Ultrasound (UAE) and microwave (MAE) assisted extractions were performed in order to obtain the extracts. The total polyphenol (TPC) and total tannin (TTC) contents of the extracts were assessed via the Folin–Ciocâlteu method. The volatile and polyphenolic compounds were identified and quantified via a GC/MS analysis and an UPLC-PDA analysis, respectively. The antioxidant activity (AOA) was evaluated using the DPPH and ABTS assays, while the antibacterial activity was assessed using the minimum inhibitory concentration (MIC) protocol. The results showed that the Pinus sylvestris bark extracts obtained by UAE had a higher TPC, TTC and AOA, while the Pinus nigra bark extracts obtained by MAE had higher volatile compounds content (mainly α-pinene and β-pinene). Moreover, the inhibition of the bacterial growth was more efficient in the case of Pinus sylvestris extracts, Gram-positive bacteria being the most affected, while Gram-negative strains presented a relative resistance to the tested extract concentrations. These results may indicate the potential use of the pine bark extracts as antioxidant or antibacterial agents.

Impact of the incorporation of date pit flour an underutilized biowaste in dough and its functional role as a fat replacer in biscuits

Date pit (Phoenix dactylifera L.), an underutilized biowaste, is the major by-product of the date processing industry. Date pits (DPs) are the naturally rich sources of several bioactive compounds that play a vital role in the prevention of the diseases. In the present study, the effect of date pit flour (DPF) as a fat replacer in biscuits at different concentrations (10, 20, 30, and 40% wt/wt) was explored. The proximate, functional, rheological, microstructural, phytochemical, antioxidant, nutritional, and sensory properties of the flour and the biscuits samples were evaluated. The results demonstrated that different ratios of DPF and wheat flour (WF) had high contents of ash, crude fibers, proteins, phytochemicals, and antioxidant activity in contrast to the commercial WF that showed lowest values for all the above components. It was observed that the inclusion of DPF (used in same percentage as fat replacer in biscuit formulation) in the WF alters dough rheology significantly. The gluten content of the flour blends decreased with the addition of DPF while the water absorption increased that interfere in the gluten development time, and it was increased from 1.67 min for control (without DPF) to 7 min for 40% DPF substitution. The scanning electron microscopy of biscuits dough elaborated after fat replacement at different levels showing that evenly distribution of starch granule was disrupted, and the gluten matrix was often ruptured. The total phenolic content (TPC) and total flavonoid content (TFC) increased from 18.56 to 451.60 mg GAE/100 gm of sample and 27.43 to 361.20 mg CE/100 g, respectively. Although, baking decreased the TPC, whereas TFC was increased as compared to the control, and similar results were observed for the antioxidant activity for other substituted biscuits. The crude fiber and protein contents of DPF-WF biscuits were improved from 0.44% to 8.70% and 11.79 to 12.69%, respectively, Sensory and textural performance exhibited that the biscuits were acceptable after fat replacement up to 20% DPF. Based on this study, DPF may be suggested as an excellent natural fat replacer to be used in nutraceuticals and functional foods. Practical applications The current approach enhances the economy of date processing industries by providing value to waste as date pits (DPs). Furthermore, it may be suggested that date pit flour (DPF) is a valuable food industry waste that may play highly beneficial role in producing bakery products of enhanced nutritional values at economical cost. The study had shown that certain compounds of DPF such as proteins, fibers, and phytochemicals which apart from being active and important nutrients may contribute to desirable functional properties by closed interactions at the molecular level between the components of major ingredients. The mixing process provides opportunities to form complexes from these interactions that further react during baking when a suitable thermal atmosphere is available. It seems that introducing DPF is a good discovery that has opened the wide door for numerous novel nutraceutical product development and simultaneously making use of food industry by-products.

Metabolites and Biological Activities of some Pulicaria species (Asteraceae): mini-review

Medicinal plants are a prominent source of secondary metabolites and bioactive innovative molecules with interesting and remarkable biological activities. The Sinai Peninsula is considered an exceptional reservoir of many indigenous medicinal plants that have been used for treatment of many ailments; Pulicaria is a promising medicinal genus and one of the widest spread desert plants growing wild in Egypt. Some plants within the genus are used as traditional herbal medicines. Pulicaria is a well-known natural source of several bioactive compounds and used in traditional medicine in the many countries. Most importantly, previous studies of Pulicaria species allowed the isolation of various compounds such as flavonoids and terpenes. Our review tends to support the therapeutic value of this genus. Many recent studies suggested that most of the reported biological activities of Pulicaria are due to its high content of polyphenols, particularly flavonoids. This review highlights the phytochemical constituents of this important and valuable genus as well as its different reported biological activities.

Essential oils as microbial reductant

Essential oils are concentrated liquids of complex mixtures of volatile compounds and can be extracted from several plant organs. Essential oils are a good source of several bioactive compounds, which possess antioxidative and antimicrobial properties. In addition, some essential oils have been used as medicine. Furthermore, the uses of essential oils have received increasing attention as the natural additives for the shelf‐life extension of food products, due to the risk in using synthetic preservatives. Essential oils can be incorporated into packaging, in which they can provide multifunctions termed “active or smart packaging.” Those essential oils are able to modify the matrix of packaging materials, thereby rendering the improved properties. This review covers up‐to‐date literatures on essential oils including sources, chemical composition, extraction methods, bioactivities, and their applications, particularly with the emphasis on preservation and the shelf‐life extension of food products. Keywords: Essential oils , antioxidative , antimicrobial , shelf‐life and packaging .

Characterization of a Coproduct from the Sea Cucumber Cucumaria frondosa and Its Effects on Visceral Adipocyte Size in Male Wistar Rats.

Sea cucumbers have been shown to have potential health benefits and are a rich source of several bioactive compounds, particularly triterpenoid saponins. However, most studies concentrate on the body wall, and little is known about the health effects of the coproducts. The objectives of this study were to determine the nutritional composition of a coproduct from the sea cucumber Cucumaria frondosa and the effects of the dietary consumption of this coproduct on cardiometabolic health in rats. Chemical, biochemical, and nutritional analyses were performed to characterize this coproduct. Forty (40) male Wistar rats were then equally divided into four groups and fed a purified control diet or a diet enriched with 0.5%, 1.5%, or 2.5% (by protein) of coproduct. After 28 days of feeding, the rats were sacrificed. Body and tissue weight, body composition, epididymal adipocyte diameter, plasma and hepatic lipids, glycemia, and insulinemia were measured at the end of the 28-day experiment. Analysis of the coproduct revealed high levels of protein, omega-3 fatty acids, minerals, and saponins. The 1.5% group had significantly smaller epididymal adipocytes vs. the control. We conclude that dietary administration of this sea cucumber coproduct at 1.5% doses decreases visceral adiposity, potentially decreasing the risk of cardiometabolic dysfunction. The coproduct’s saponin content may contribute to the observed effects, but the impact of other components cannot be ruled out.

Optimisation of the extraction process of antioxidant capacity compounds from beet (Beta vulgaris L.) stalk

Beet is a traditional root consumed worldwide and is considered a potential source of several bioactive compounds, yet during production and commercialisation activities, its leaves and stalks are discarded. The beet residue has notable quantities of diverse phenolic compounds that are not taken advantage of it. The beet stalks (sample) were obtained from a local producer at the municipality of Marechal Cândido Rondon, Paraná state, Brazil. The optimisation of the extraction process of antioxidant capacity compounds from beet stalk was done by response surface methodology (RSM), with three independent variables (time, from 5 to 85 min; temperature, from 20 to 80 °C and solvent, from 0 to 100% of ethanol/water ratio). Extracts were evaluated for their reducing capacity, measured by the Folin–Ciocalteu method, and antioxidant capacity by the ability to scavenge DPPH and ABTS free radicals. The optimal global extraction conditions determined were 5 min, 80 °C and 50% ethanol, yielding 13.157 mg gallic acid equivalents (GAE) g–1, 21.539 mol Trolox equivalents g-1 (TE; DPPH) and 250.190 ?mol TE g–1 (ABTS). Beet stalk demonstrated to be an alternative and rich source of recovering of natural antioxidant compounds, showing higher contents when compared to other agro-industrial residues.

Extraction of Essential Oils from Medicinal Plants and their Utilization as Food Antioxidants.

The use of essential oils is receiving increasing attention worldwide, as these oils are good sources of several bioactive compounds. Nowadays essential oils are preferred over synthetic preservatives thanks to their antioxidant and antimicrobial properties. Several studies highlight the beneficial effect of essential oils extracted from medicinal plants to cure human diseases such as hypertension, diabetes, or obesity. However, to preserve their bioactivity, the use of appropriate extraction technologies is required. The present review aims to describe the studies published so far on the essential oils focusing on their sources and chemical composition, the technologies used for their recovery and their application as antioxidants in food products. The review has been structured in three parts. In the first part, the main compounds present in essential oils extracted from medicinal plants have been listed and described. In the second part, the most important technologies used for extraction and distillation, have been presented. In detail, conventional methods have been described and compared with innovative and green technologies. Finally, in the last part, the studies related to the application of essential oils as antioxidants in food products have been reviewed and the main findings discussed in detail. In summary, an overview of the aforementioned subjects is presented by discussing the results of the most recent published studies.

Simultaneous extraction and purification of fucoxanthin from Tisochrysis lutea microalgae using compressed fluids

The marine microalga Tisochrysis lutea, a Haptophyta with a thin cell wall and currently used mainly in aquaculture is a potential source of several bioactive compounds of interest such as carotenoids. In the present study, the simultaneous extraction and purification of fucoxanthin, the main carotenoid from T. lutea, was optimized using pressurized fluid extraction followed by in-cell purification. An experimental design was employed to maximize carotenoids' extraction; the experimental factors chosen were: (i) percentage of ethanol/ethyl acetate (0-100 %), (ii) temperature (40-150°C), and (iii) number of static extraction cycles (1-3). The maximum carotenoids' recovery, mainly fucoxanthin, was obtained with pure ethyl acetate at 40°C using one extraction cycle, achieving values of 132.8mg of carotenoids per gram of extract. Once the optimum extraction conditions were confirmed, in-cell purification strategies using different adsorbents were developed to obtain fucoxanthin-enriched extracts. Activated charcoal showed potential retention of chlorophylls allowing an effective purification of fucoxanthin in the obtained extracts. Chemical characterization of extracts was carried out by reversed-phase high-performance liquid chromatography with diode array detection. Therefore, a selective fractionation of high value compounds was achieved using the proposed green downstream platform based on the use of compressed fluids.