Optimiranje postupka obrade nektara graviole (Annona muricata) toplinom i ultrazvukom, te usporedba fizikalno-kemijskih svojstava i biološke raspoloživosti antioksidansa in vitro optimiranog nektara s pasteriziranim uzorkom

Research background. Soursop nectar contains antioxidants and is preserved by pasteurization. However, this technology impairs its physicochemical properties and bioactive compounds. An alternative is therefore thermoultrasound, which could counteract these effects. The thermosonicated nectar was compared with a pasteurized one and the in vitro bioaccessibility of antioxidants was estimated. Experimental approach. The soursop nectar (25 %) was processed and the response surface methodology was used to determine the optimal conditions for thermoultrasound treatment (TUS). The TUS (75–90 % amplitude, 3.15–15 min) was applied, and 2 % stevia and 6 % agave inulin were added as sweeteners. The microbiological, physicochemical, enzymatic and antioxidant properties were analyzed. The properties of thermosonicated nectar obtained under optimal conditions were compared with pasteurized nectar. In addition to the above determinations, microstructure, total dietary fiber (TDF) and in vitro bioaccessibility of antioxidants were determined. Results and conclusions. The response variables that fit the mathematical model were L*, b*, chroma (C*), total phenolic content (TPC) and antioxidant activity determined by ABTS•+, DPPH˙ and Fe(III) reducing antioxidant power (FRAP). The L* and DPPH˙ were affected by quadratic time and TPC by time (p<0.0001). The optimum TUS condition was 82 % amplitude for 9.15 min and the responses variables were L*, b* and C* (45.48, 3.55 and 3.62, respectively), TPC expressed as gallic acid equivalents (38.40 mg/100 mL), ABTS•+ expressed as Trolox equivalents (TE) (31.28 μmol/100 mL), DPPH˙ expressed as TE (124.22 μmol/100 mL) and FRAP expressed as Fe(II) (3.06 μmol/100 mL). Compared to the pasteurized sample, thermosonicated sample had high values of L* (45.56), h° (-56.49), TPC (26.63 mg/100 mL), ABTS•+ and DPPH˙ (22.03 and 129.22 μmol/100 mL, respectively), FRAP (3.10 μmol/100 mL) and low pectin methylesterase (PME) activity (0.28 U/mL). For in vitro bioaccessibility, thermosonicated nectar showed high absorption of TPC (15.26/100 mL) and high antioxidant activity determined by ABTS (34.92 μmol/100 mL) and FRAP (7.88 μmol/100 mL). Novelty and scientific contribution. The thermoultrasound improves the physicochemical properties and in vitro bioaccessibility of antioxidants in soursop nectar. On the other hand, as an alternative, this beverage offers low-calorie alternative with prebiotic properties that benefits consumer health.Pozadina istraživanja. Nektar graviole sadržava antioksidanse, a radi produljenja roka trajanja tretira se pasterizacijom. Međutim, taj postupak narušava fizikalno-kemijska svojstva nektara i smanjuje količinu biološki aktivnih tvari u njemu. Stoga se kao alternativna metoda koristi kombinacija obrade toplinom i ultrazvukom. U radu smo usporedili svojstva nektara obrađenog toplinom i ultrazvukom s onima pasteriziranog uzorka te ispitali biološku raspoloživost antioksidansa in vitro. Eksperimentalni pristup. Obrađen je nektar graviole (s 25 % voćnog soka), a metodom odzivnih površina određeni su optimalni uvjeti obrade toplinom i ultrazvukom. Primijenjen je ultrazvuk amplitude 75-90 % tijekom 3,15–15 min, a kao zaslađivači su dodani 2 % stevije i 6 % inulina iz agave. Ispitana su mikrobiološka, fizikalno-kemijska, enzimska i antioksidacijska svojstva. Svojstva nektara dobivenog obradom toplinom i ultrazvukom pri optimalnim uvjetima uspoređena su s onima pasteriziranog uzorka. Osim toga, određeni su mikrostruktura, ukupna količina prehrambenih vlakana i in vitro biološka raspoloživost antioksidansa. Rezultati i zaključci. Varijable koje su odgovarale matematičkom modelu bile su L*, b*, zasićenost boje (C*), ukupni udjel fenola i antioksidacijska aktivnost određena metodama ABTS˙+, DPPH˙ i FRAP. Na vrijednost L* i sposobnost uklanjanja DPPH˙ utjecali su kvadratna vrijednost vremena te interakcija ukupnog udjela fenola i vremena (p<0,0001). Optimalni uvjeti obrade toplinom i ultrazvukom bili su amplituda 82 % tijekom 9,15 min, a odzivne varijable bile su L* (45,48), b* (3,55 ) i C* (3,62), ukupni udjel fenola izražen u ekvivalentima galne kiseline (38,40 mg/100 mL), sposobnost uklanjanja ABTS˙+ izražena u Trolox ekvivalentima (TE) (31,28 μmol/100 mL), sposobnost uklanjanja DPPH˙ izražena u TE (124,22 μmol/100 mL) i FRAP izražen kao Fe(II) (3,06 μmol/100 mL). U usporedbi s pasteriziranim uzorkom, dobiveni je nektar imao velike vrijednosti L* (45,56), h° (–56,49), ukupnog udjela fenola (26,63 mg/100 mL), dobru sposobnost uklanjanja ABTS˙+ (22,03 μmol/100 mL) i DPPH˙ (129,22 μmol/100 mL), veliku vrijednost FRAP (3,10 μmol/100 mL), a malu aktivnost metil esteraze (0,28 U/mL). Ispitivanje in vitro bioraspoloživosti antioksidansa pokazalo je da dobiveni nektar ima veliku biorapoloživost ukupnog udjela fenola (15,26/100 mL) i izraženu antioksidacijsku aktivnost, određenu pomoću ABTS (34,92 μmol/100 mL) i FRAP (7.88 μmol/100 mL) metoda. Novina i znanstveni doprinos. Obradom toplinom i ultrazvukom poboljšana su fizikalno-kemijska svojstva i in vitro biološka raspoloživost antioksidansa iz nektara graviole. Dobiveni napitak može poslužiti kao niskokalorična alternativa s prebiotičkim svojstvima i pozitivnim učinkom na zdravlje korisnika

BIOACTIVE PEPTIDES IN RED MEATS, BYPRODUCTS AND RESIDUES FROM THE MEAT INDUSTRY

O Objective: To provide a comprehensive overview of the generation of bioactive peptides from raw red meat, its by-products, and the waste meat cuts, as well as the bioactive health effects. Design/methodology/approach: A literature search was conducted through the organization and systematized analysis of information for an updated literature review of bioactive peptides in red meat. Results: Meat is a food of great nutritional value for human beings, since the digestibility of its protein stands out. In addition to the nutritional value of this protein, there are some studies in meat where bioactive peptides provide bioactivity mainly as an antihypertensive and antioxidant. Bioactive peptides are generally obtained by enzymatic hydrolysis and through microbial fermentation processes. Subsequently, they are identified by analytical techniques to perform in vitro and in vivo evaluations verifying the bioactivity of the peptides obtained. Limitations on study/implications: The food industry must establish the most reliable methods for generating more reliable peptides to standardize their production and avoid process variability. Findings/conclusions: The bioactive activity to be exerted by the peptides will depend on factors specific to the protein, such as the number of amino acids it contains, the hydrophilic or hydrophobic profile, and size, among others. This information is key to predict the activity the peptide can exert in the human body since many can have multiple activities, the most common being the antioxidant-antihypertensive function

Valorización de los subproductos del procesamiento de la zarzamora (rubus fruticosus), por su contenido en antioxidantes y fibra dietética.

El procesamiento de los frutos de la zarzamora en jugo genera subproductos los cuales contienen compuestos antioxidantes como los fenoles, además de fibra dietética que pueden ser aprovechados en la industria farmacéutica o de los alimentos. Por otro lado, se ha visto que el ultrasonido se utiliza como metodología para la extracción de compuestos fenólicos. Por tanto, el objetivo del presente estudio fue valorizar los subproductos del procesamiento de la zarzamora (género Rubus, familia Rosaceae) por su contenido en antioxidantes y fibra dietética

In Vitro Probiotic Potential of Lactic Acid Bacteria Isolated from Aguamiel and Pulque and Antibacterial Activity Against Pathogens

Probiotics can act as a natural barrier against several pathogens, such Helicobacter pylori, a bacterium linked to stomach cancer. The aim of the present study was to isolate and identify lactic acid bacteria (LAB) from pulque and aguamiel, and evaluate their probiotic potential and antimicrobial effect on Escherichia coli, Staphylococcus aureus, and Helicobacter pylori. Ten isolates were selected and evaluated for in vitro resistance to antibiotics and gastrointestinal conditions, and antimicrobial activity against E. coli and S. aureus and the effect on H. pylori strains. 16S rRNA identification was performed. Ten potential probiotic isolates were confirmed as belonging to the genera Lactobacillus and Pediococcus. All the strains were susceptible to clinical antibiotics, except to vancomycin. Sixty percent of the isolates exhibited antimicrobial activity against E. coli and S. aureus. The growth of H. pylori ATCC 43504 was suppressed by all the LAB, and the urease activity from all the H. pylori strains was inhibited, which may decrease its chances for survival in the stomach. The results suggest that LAB isolated from pulque and aguamiel could be an option to establish a harmless relationship between the host and H. pylori, helping in their eradication therapy

Organic Acids, Antioxidants, and Dietary Fiber of Mexican Blackberry (Rubus fruticosus) Residues cv. Tupy

Blackberry fruit processing generates residues comprised of peel, seeds, and pulp that are abundant in flavonoids, colorants, and organic acids. The objective of this study was to determine the organic acids, antioxidants, and dietary fiber content of blackberry residues and compare antioxidants and dietary fiber content of a prune-based commercial product. The ABTS, DPPH, and FRAP methodologies were used for antioxidant capacity. The blackberry residues exhibited a high amount of malic acid (5706.37 mg/100 g db), phenols (4016.43 mg GAE/100 g db), and anthocyanins content (364.53 mg/100 g db) compared with the commercial product. These compounds contributed to the antioxidant capacity (by ABTS) of both products but were 20 times higher in blackberry residues. The fruit residues were able to reduce iron (by FRAP) 4.4 times compared to the prune-based product. Total dietary fiber (44.26%) and functional properties as water retention capacity (2.94 g/g), swelling capacity (5.00 mL/g), and fat absorption capacity (1.98 mL/g) of blackberry residues were significantly higher than those of the commercial sample. The results demonstrated that, due to its antioxidant compounds and functional properties, the blackberry residue can be considered a source of components with potential benefit to human health

Application of Ultrasound in a Closed System: Optimum Condition for Antioxidants Extraction of Blackberry (Rubus fructicosus) Residues

Blackberry processing generates up to 20% of residues composed mainly of peel, seeds and pulp that are abundant in flavonoids. The objective of this study was to optimize the ultrasound conditions, in a closed system, for antioxidants extraction, using the response surface methodology. Blackberry (Rubus fructicosus) residues were analyzed for total phenolics, total anthocyanins, and antioxidant activity by ABTS and DPPH. The selected independent variables were ultrasound amplitude (X1: 80%–90%) and extraction time (X2: 10–15 min), and results were compared with conventional extraction methods. The optimal conditions for antioxidants extraction were 91% amplitude for 15 min. The results for total phenolic content and anthocyanins and antioxidant activity by ABTS and DPPH were of 1201.23 mg gallic acid equivalent (GAE)/100 g dry weight basis (dw); 379.12 mg/100 g·dw; 6318.98 µmol Trolox equivalent (TE)/100 g·dw and 9617.22 µmol TE/100 g·dw, respectively. Compared to solvent extraction methods (water and ethanol), ultrasound achieved higher extraction of all compounds except for anthocyanins. The results obtained demonstrated that ultrasound is an alternative to improve extraction yield of antioxidants from fruit residues such as blackberry

Role of Bioactive Compounds in Obesity: Metabolic Mechanism Focused on Inflammation

Obesity is a disease characterized by an inflammatory process in the adipose tissue due to diverse infiltrated immune cells, an increased secretion of proinflammatory molecules, and a decreased secretion of anti-inflammatory molecules. On the other hand, obesity increases the risk of several diseases, such as cardiovascular diseases, diabetes, and cancer. Their treatment is based on nutritional and pharmacological strategies. However, natural products are currently implemented as complementary and alternative medicine (CAM). Polyphenols and fiber are naturally compounds with potential action to reduce inflammation through several pathways and play an important role in the prevention and treatment of obesity, as well as in other non-communicable diseases. Hence, this review focuses on the recent evidence of the molecular mechanisms of polyphenols and dietary fiber, from Scopus, Science Direct, and PubMed, among others, by using key words and based on recent in vitro and in vivo studies

Applications and Pharmacological Properties of Cactus Pear (<i>Opuntia</i> spp.) Peel: A Review

Nowadays, there is a growing interest in the exploitation of by-products from fruits and vegetables, generated from industrial processing or human feeding. Residues of popularly consumed fruits such as orange, lemon, banana, pomegranate, among others, have been widely described and studied; however, cactus pear (Opuntia spp.) residues, as a locally consumed product, have been forgotten. The whole fruit can be divided into the edible portion (pulp) and the non-edible portion (seeds and peel). Several studies mainly focus on the characteristics of the edible portion or in the whole fruit, ignoring by-products such as peels, which are rich in compounds such as phenols, flavonoids and dietary fiber; they have also been proposed as an alternative source of lipids, carbohydrates and natural colorants. Some uses of the peel have been reported as a food additives, food supplements, as a source of pectins and for wastewater treatment; however, there have not been any deep investigations of the characteristics and potential uses of the cactus pear peel (CPP). The aim of the present paper is to provide an overview of the current research on CPP. CPP has many bio-active compounds that may provide health benefits and may also be useful in pharmaceutical, food and manufacturing industries; however, greater research is needed in order to gain thorough knowledge of the possibilities of this by-product