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- Impact of enzyme- and ultrasound-assisted extraction methods on biological properties of red, brown, and green seaweeds from the Central West Coast of PortugalPublication . Rodrigues, Dina; Sousa, Sérgio; Silva, Aline; Amorim, Manuela; Pereira, Leonel; Rocha-Santos, Teresa A.P.; Gomes, Ana M. P.; Duarte, Armando C.; Freitas, Ana CristinaSeaweeds are an excellent source of bioactive compounds, and therefore the use of sustainable and food compatible extraction methods such as enzyme-assisted (EAE) and ultrasound-assisted extraction were applied on Sargassum muticum, Osmundea pinnatifida, and Codium tomentosum. Extracts were evaluated for proximate characterization and biological properties. Higher extraction yields were observed for C. tomentosum EAE (48-62%; p < 0.05 for Cellulase and Viscozyme), followed by O. pinnatifida (49-55%; p < 0.05 except Alcalase) and S. muticum (26-31%; p < 0.05). S. muticum extracts presented the highest nitrogen (25 +/- 2 mg/g(lyoph) (extract)) and total phenolics (261 +/- 37 mu g(catechol) (equiv)/gl(yoph) (extract)) contents, whereas higher sugars (78 +/- 14 mg(glucose) (equiv)/g(lyoph) (extract)) including sulfated polysaccharide (44 +/- 8 mg(Na2SO4) (acid)/g(lyoph) (extract)) contents characterized O. pinnatifida extracts. A higher effect on hydroxyl-radical scavenging activity (35-50%) was observed for all extracts, whereas S. muticum Alcalase and C. tomentosum Cellulase extracts exhibited higher prebiotic activity than fructooligosaccharides. O. pinnatifida and C. tomentosum EAE showed inhibitory potential against alpha-glucosidase (38-49%).
- Bioactive properties of peptides obtained from Argentinian defatted soy flour protein by Corolase PP hydrolysisPublication . Coscueta, Ezequiel R.; Amorim, Maria M.; Voss, Glenise B.; Nerli, Bibiana B.; Picó, Guillermo A.; Pintado, M. E.Enzymatic hydrolysis of soybean meal protein isolate (SPI) obtained under two temperature conditions with Corolase PP was studied, assessing the impact of hydrolysis on potential antioxidant and antihypertensive activities. The protein was isolated from soybean meal under controlled conditions of time and temperature (70 C, 1 h; 90 C, 30 min). Degree of hydrolysis assessed the progress of hydrolysis at different sampling times. For hydrolysates the antioxidant and angiotensin-converting-enzyme (ACE) inhibitory activities were measured. As observed, the DH was increasing until reaching 20% at 10 h with disappearance of globular proteins and generation of low molecular weight peptides (less than 3 kDa). A significant increase in antioxidant and ACE inhibitory capacities was observed. Five main peptides were identified, which may explain through their sequences the bioactive properties analyzed. Through this study was possible to obtain for the first time with Corolase PP soy hydrolysates with potential antioxidant and ACE inhibitory activities, which can be used to obtain new added value functional ingredients from soy meal.
- Effects of whey peptide extract on the growth of probiotics and gut microbiotaPublication . Yu, Ya-Ju; Amorim, Manuela; Marques, Cláudia; Calhau, Conceição; Pintado, M. E.Whey peptide extract with molecular weight below 1 kDa was investigated in microplate assay, and viable cells, as well as metabolic activity were determined to evaluate augmented growth of probiotic bacteria (Lactobacillus acidophilus and Bifidobacterium animalis). Results illustrated that whey peptide extract 1% (w/v) has the capacity to stimulate the proliferation of both probiotic bacteria tested, further supported by the faster generation of metabolic products. The effect of whey peptide extract on the modulation of gut microbiota was also examined inWistar rats fed either with a standard or a high-fat diet, assessed via 16S ribosomal RNA expression of gut microbiota by quantitative PCR. Relative abundance of Lactobacillus spp., Bifidobacterium spp. and Bacteroidetes was significantly increased by whey peptide extract in rats fed with a standard diet. These results highlight an additional unexploited positive effect of whey peptide extract on gut microbiota modulation.
- Antihypertensive effect of spent brewer yeast peptidePublication . Amorim, M.; Marques, C.; Pereira, J. O.; Guardão, L.; Martins, M. J.; Osório, H.; Moura, D.; Calhau, C.; Pinheiro, H.; Pintado, M.Numerous studies have investigated dietary approaches to prevent chronic lifestyle-related diseases, including hypertension. Spent brewer's yeast is the second largest byproduct originated by the brewing industry and it deserves considerable attention because of its high nutritional value, ca. 40% of its dry mass is rich in protein which can be hydrolyzed into biologically active peptides. To upgrade this byproduct, the aim of this study was initially in vitro assessment of biological properties, e.g. ACE inhibition and antioxidant activity, and then, the in vivo effect in short-term oral antihypertensive effect of hydrolyzed yeast fractions on a well characterized model to study hypertension - Spontaneously Hypertensive Rats (SHR). Here, it was demonstrated that the fraction with molecular weight below 3 kDa containing tri and tetra- peptides with hydrophobic amino acid residues - SPQW, PWW and RYW, causes the most noticeable decrease in systolic, diastolic and mean blood pressure of SHR and shows highest antioxidant effect. These properties highlight the potential use of yeast extract as nutraceutical or functional food ingredient for the management and treatment of hypertension with antioxidant effect.
- Nanoencapsulation of bovine lactoferrin for food and biopharmaceutical applicationsPublication . Balcão, Victor M.; Costa, Carla I.; Matos, Carla M.; Moutinho, Carla G.; Amorim, Manuela; Pintado, Manuela E.; Gomes, Ana M. P.; Vila, Marta M.; Teixeira, Jose A.Lactoferrin has for long captured the interest of many researchers as a natural compound with a wide variety of uses. Lactoferrin is a monomeric, iron-binding 80 kDa glycoprotein, and appears to be the subfraction of whey with the best documented antiviral, antimicrobial, anticancer and immune modulating/enhancing effects. It belongs to the family of transferrin proteins, and serves to control iron levels in body fluids by sequestering and solubilizing ferric iron. In the present research effort, production of lactoferrin derivatives (starting from a purified commercial extract), encompassing full stabilization of its three-dimensional structure, has been attempted via nanoencapsulation within lipid nanovesicles, integrating a multiple water-in-oil-in-water emulsion. Long-term storage of the multiple nanoemulsions produced did not lead to leaching of protein, thus proving the effectiveness of the encapsulation procedure. Furthermore, lactoferrin nanovesicle derivatives prepared under optimal conditions were successfully employed at lab-scale antimicrobial trials.
- Chemical and structural characterization of Pholiota nameko extracts with biological propertiesPublication . Rodrigues, Dina; Freitas, Ana C.; Sousa, Sérgio; Amorim, Manuela; Vasconcelos, Marta W.; Costa, João P. da; Silva, Artur M. S.; Rocha-Santos, Teresa A. P.; Duarte, Armando C.; Gomes, Ana M. P.Edible mushrooms including Pholiota nameko are excellent sources of extractable bioactive compounds with much to explore. Enzymatic extractions with Cellulase and Viscozyme were responsible for highest extraction yields (67-77%). No strong antioxidant activity was observed although extracts were able to scavenge ABTS(+) and OH(+). Potential prebiotic activity was observed in all extracts, some increasing 1.4-2 Log cycles of Lactobacillus acidophilus La-5 and Bifidobacterium animalis BB12. 30-50% α-glucosidase inhibition was observed in ultrasound, Flavourzyme and Cellulase extracts. Flavourzyme and Cellulase extracts are richer in macro (Mg, K and P) and micro elements (Zn, Mn and Fe) in comparison to mushroom. Monosaccharides content and profile varied slightly among both extracts with predominance of glucose, galactose and mannose with no uronic acids detection; Flavourzyme extract reported higher free amino acids content. Presence of α and β-glycosidic structures such as glucans and glucan-protein complexes are among the polysaccharides found in both extracts.
- Effect of modified chitooligosacharides on the physicochemical and microbiological characteristics of a probiotic fermented beveragePublication . Gallina, Darlila Aparecida; Pacheco, Maria Teresa Bertoldo; Barbosa, Paula de Paula Menezes; Amorim, Maria Manuela Faria; Cobas, Alejandra CardelleThe effect of the addition of chitooligosaccharides modified with glucose (COS-Glc), with potential prebiotic activity, on a smoothie beverage was evaluated during the storage. Two probiotic smoothie formulations made with probiotic yogurt (60%) and mango pulp (40%) were prepared, as follows: formulation F1 containing 2.0 % COS-Glc, and formulation F2 without the addition of COS-Glc (control). Commercial probiotic culture of Bifidobacterium lactis ssp. was used in both formulations. The products were evaluated for hygienic-sanitary quality, physicochemical composition, titratable acidity, syneresis, and bacteria viability (selective enumeration of Lactobacillus delbrueckii subsp. bulgaricus, Streptococcus thermophilus, and Bifidobacterium spp.) after one day of manufacture. The viability of the microorganisms, the hygienic-sanitary quality and the physicochemical characteristics (titratable acidity and syneresis) of the beverages were evaluated throughout 30 days of storage at 8 +/- 1 degrees C. The hygienic-sanitary quality was satisfactory, and the beverages were suitable for consumption. The addition of modified chitooligosaccharides to the probiotic beverage led to an increase in titratable acidity and syneresis. The formulation F1 presented significantly higher total solids, total dietary fiber, and carbohydrates when compared to F2. The addition of COS-Glc did not affect the viability of the probiotics in the beverage along with the storage, which remained within the recommended dose to exert its therapeutic effect. The combination of COS-Glc and probiotics can be an interesting tool to produce smoothie type dairy beverages without adversely affecting the characteristics of the product, besides conferring added value to the product due to the incorporation of an ingredient with potential prebiotic activity.
- Development of a cashew nut coated with bioactive whey peptide extract with antihipertensivePublication . Pereira, Joana Odila; Amorim, Manuela; Silva, L. B.; Ormenese, R.C.S.C.; Pacheco, M.T.B.; Pintado, ManuelaThere is a growing concern in the consumer’s habits seeking healthy foods, which has opened new markets for functional foods. This global demand led to the development of functional foods, searching new ingredients to incorporate into conventional foods. Whey proteins are studied not only from the nutritional and functional properties, but also as a source of peptides that may exert biological functions, particularly antihypertensive activity. These bioactive peptides are released by enzymatic hydrolysis and according the final composition they may exert biological activities. Cashew nut was used as matrix for incorporation functional ingredients due to its nutritional properties conveyed by the high content of folic acid and essential fatty acids. The aim of this study was to develop a cashew nut coated with peptide fraction obtained from whey and to evaluate the antihypertensive activity and consumer acceptance of the new functional cashew nuts. The fraction with MW < 3000 Da was obtained by hydrolysis of whey with Cynara cardunculus followed by nanofiltration to obtain low MW fraction, exhibited very high ACE-inhibitory activity, IC50 12.8 μg /mL protein. The incorporation of peptides (2 %) in cashew nut led to a reduction to values of ACEinhibitory activity, 532.2 μg/mL. However, this is close the values reported by other products in the market claiming antihypertensive activity. In the formulation there is space to increase concentration and biological activity. Nevertheless, it is important to highlight that the antihypertensive activity was not lost even when high temperatures during coating and processing of the product were used. The sensory analysis of the functional cashew nut showed high acceptability by the consumers. Our results suggest that the application of these bioactive peptide extracts with antihypertensive activity in the development of a new snacks with reduce salt content is promising in the improvement of new value-added food products.
- Optimisation, by response surface methodology, of degree of hydrolysis and antioxidant and ACE-inhibitory activities of whey protein hydrolysates obtained with cardoon extractPublication . Tavares, T. G.; Contreras, M. M.; Amorim, M.; Martín-Álvarez, P. J.; Pintado, M. E.; Recio, I.; Malcata, F. X.The hydrolysis of bovine whey protein concentrate (WPC), alpha-lactalbumin (alpha-La) and caseinomacropeptide (CMP), by aqueous extracts of Cynara cardunculus, was optimized using response surface methodology. Degree of hydrolysis (DH), angiotensin-converting enzyme (ACE)-inhibitory activity and antioxidant activity were used as objective functions, and hydrolysis time and enzyme/substrate ratio as manipulated parameters. The model was statistically appropriate to describe ACE-inhibitory activity of hydrolysates from WPC and alpha-La, but not from CMP. Maximum DH was 18% and 9%, for WPC and alpha-La, respectively. 50% ACE-inhibition was produced by 105.4 (total fraction) and 25.6 mu g mL(-1) (<3 kDa fraction) for WPC, and 47.6 (total fraction) and 22.5 mu g mL(-1) (<3 kDa fraction) for alpha-La. Major peptides of fractions exhibiting ACE-inhibition were sequenced. The antioxidant activities of WPC and alpha-La were 0.96 +/- 0.08 and 1.12 +/- 0.13 mmol trolox equivalent per mg hydrolysed protein, respectively.
- Formulation and consumer acceptance of cereal bars with functional properties by the incorporation of peptides and β- glucans from Spent Brewer's YeastPublication . Amorim, Manuela; Pereira, Joana; Pinheiro, Hélder; Pacheco, Maria Teresa; Pintado, ManuelaThe market for functional ingredients and foods has a high growth due to increased awareness and promotion of healthy eating and lifestyle of consumers. Food can be used as vehicle to intake bioactive compounds that provide health benefits and increase people well-being. Thus, cereal bars are a popular and convenient food, which is an ideal carrier to incorporate functional ingredients that promote health and prevent diseases. The design and development of functional foods should not be made based solely on nutritional function without taking into account product properties, such as color, texture, flavor and taste. The sensory properties are the most important attributes for the consumer acceptance, as well as other quality issues such as stability and texture. This work was focused on the formulation and sensory analysis of cereal bars obtained by incorporation of peptides and β-glucans extract obtained via autolysis and hydrolysis of spent brewer’s and presenting biological activities such as, antihypertensive and prebiotic. However, this ingredient results in particular taste and flavor that may constrain the matrix choice and consumer acceptance. The cereal bar was formulated based on oat, rice and corn and added 2% extract. Consumer acceptance tests were performed to test general acceptability in particular for the appearance, aroma, flavor and texture by hedonic scale of nine points (9 = liked a lot and 1 = dislike very much) and intent to purchase of 5 point scale (5= definitely would buy and 1= definitely would not buy). The final cereals bars were assessed by 52 consumers and showed positive response since "like" for all attributes were obtained. Regarding the intention to purchase, the sample had an average between "maybe bought" and "probably would buy". So these results suggest that cereal bar is an adequate matrix to produce a functional food with antihypertensive and prebiotic activity based on spent brewer's yeast bioactive ingredient.
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