Characterisation of phenolic compounds in processed fibres from the juice industry

Enhanced physicochemical properties, structure, and in vitro digestibility of olive oil-infused pigmented popcorn prepared via microwave processing

The study investigates the composition and properties of unpopped and expanded popcorn, analyzing monosaccharides, protein, amylose, polyphenols, physical traits, crystallinity, and in vitro digestion. Unpopped grains had high glucose content (mainly from starch), which decreased by 20 % in expanded popcorn, especially in black and red A samples. Expanded grains showed higher protein levels (up to 15 %), particularly in red B and yellow samples. Amylose content ranged from 18 % to 49 %, with no clear processing trend. Polyphenol levels were generally higher in expanded popcorn, and black-blue samples exhibited the highest whiteness index (∼82.96). Popping reduced crystallinity (∼52 %), making starch more amorphous. Expanded popcorn demonstrated greater antioxidant activity (>86 %, ABTS) during oral and intestinal digestion phases, attributed to the release of bound phenolics. These results suggest pigmented popcorn expanded with EVOO could serve as a functional snack, though further research is needed to explore additional properties.

Genome-wide investigation of glycoside hydrolase 9 (GH9) gene family unveils implications in orchestrating the mastication trait of Citrus sinensis fruits

Mastication trait of citrus significantly influences the fruit's overall quality and consumer preference. The accumulation of cellulose in fruits significantly impacts the mastication trait of citrus fruits, and the glycoside hydrolase 9 (GH9) family plays a crucial role in cellulose metabolism. In this study, we successfully identified 32 GH9 genes from the Citrus sinensis genome and subsequently conducted detailed bioinformatics analyses of the GH9 family. Additionally, we profiled the spatiotemporal expression patterns of CsGH9 genes across four distinct fruit tissue types and six crucial developmental stages of citrus fruits, leveraging transcriptome data. Parallel to this, we undertook a comparative analysis of transcriptome profiles and cellulose content among diverse fruit tissues spanning six developmental stages. Furthermore, to identify the pivotal genes involved in cellulose metabolism within the GH9 family during fruit maturity, we employed correlation analysis between cellulose content and gene expression in varying tissues across diverse citrus varieties. This analysis highlighted key genes such as CsGH9A2/6 and CsGH9B12/13/14/22. Collectively, this study provides an in-depth analysis of the GH9 gene family in citrus and offers novel molecular insights into the underlying mechanisms governing the mastication trait formation in citrus fruits.

Effect of virgin olive oil as spreadable preparation on atherosclerosis compared to dairy butter in Apoe-deficient mice

Olive oil is the main source of lipid energy in the Mediterranean diet and there is strong evidence of its health benefits. The effect of extra virgin olive oil (EVOO) in the form of a preparation of spreadable virgin olive oil (S-VO) on the progression of atheroma plaques was investigated in Apoe-deficient mice, a model of accelerated atherosclerosis.

METHODS

Two isocaloric Western purified diets containing 20% fat, either as S-VO or as dairy butter, were used to feed 28 males and 16 females of two-month-old Apoe-deficient mice for 12 weeks. S-VO was prepared by blending more than 75% virgin olive oil with other vegetal natural fat to obtain a solid fat. Plasma total cholesterol, triglycerides and HDL cholesterol were measured. Hepatic lipid droplets were analyzed. Areas of atherosclerotic aortic lesions were quantified in cross-sectional images of the proximal aorta and en face analysis of the whole aorta.

RESULTS

Total plasma cholesterol was increased in mice on the butter-supplemented diet in both female and male mice compared to S-VO, and the ratio of TC/HDL-cholesterol was significantly lower in S-VO than in the butter diet, although only in males, and no differences in plasma triglycerides were observed. No significant differences in hepatic lipid droplets were observed between diets in either sex. Aortic lesion areas were significantly higher in mice consuming the butter versus the S-VO diet in both sexes.

CONCLUSION

Extra virgin olive oil prepared in spreadable form maintained the delay in atheroma plaque progression compared to butter.

Stability and Bioaccessibility of Phenolic Compounds in Rosehip Extracts during In Vitro Digestion

Rosehips, particularly dog rose fruits (Rosa canina L.), are a great source of antioxidant compounds, mainly phenolics. However, their health benefits directly depend on the bioaccessibility of these compounds affected by gastrointestinal digestion. Thus, the purpose of this research was to study the impact of gastrointestinal and colonic in vitro digestions on the concentration of total and individual bioaccessible phenolic compounds from a hydroalcoholic extract of rosehips (Rosa canina) and also their antioxidant capacity. A total of 34 phenolic compounds were detected in the extracts using UPLC-MS/MS. Ellagic acid, taxifolin, and catechin were the most abundant compounds in the free fraction, while gallic and p-coumaric acids were the main compounds in the bound phenolic fraction. Gastric digestion negatively affected the content of free phenolic compounds and the antioxidant activity measured using the DPPH radical method. However, there was an enhancement of antioxidant properties in terms of phenolic content and antioxidant activity (DPPH (2,2-diphenyl-1-picrylhydrazyl): 18.01 ± 4.22 mmol Trolox Equivalent (TE)/g; FRAP (Ferric Reducing Antioxidant Power): 7.84 ± 1.83 mmol TE/g) after the intestinal stage. The most bioaccessible phenolic compounds were flavonols (73.3%) and flavan-3-ols (71.4%). However, the bioaccessibility of phenolic acids was 3%, probably indicating that most of the phenolic acids were still bound to other components of the extract. Ellagic acid is an exception since it presented a high bioaccessibility (93%) as it was mainly found in the free fraction of the extract. Total phenolic content decreased after in vitro colonic digestion, probably due to chemical transformations of the phenolic compounds by gut microbiota. These results demonstrated that rosehip extracts have a great potential to be used as a functional ingredient.

Biosynthesis of Nanoparticles Using Plant Extracts and Essential Oils

Plant extracts and essential oils have a wide variety of molecules with potential application in different fields such as medicine, the food industry, and cosmetics. Furthermore, these plant derivatives are widely interested in human and animal health, including potent antitumor, antifungal, anti-inflammatory, and bactericidal activity. Given this diversity, different methodologies were needed to optimize the extraction, purification, and characterization of each class of biomolecules. In addition, these plant products can still be used in the synthesis of nanomaterials to reduce the undesirable effects of conventional synthesis routes based on hazardous/toxic chemical reagents and associate the properties of nanomaterials with those present in extracts and essential oils. Vegetable oils and extracts are chemically complex, and although they are already used in the synthesis of nanomaterials, limited studies have examined which molecules are effectively acting in the synthesis and stabilization of these nanostructures. Similarly, few studies have investigated whether the molecules coating the nanomaterials derived from these extracts and essential oils would bring benefits or somehow reduce their potential activity. This synergistic effect presents a promising field to be further explored. Thus, in this review article, we conducted a comprehensive review addressing the main groups of molecules present in plant extracts and essential oils, their extraction capacity, and available methodologies for their characterization. Moreover, we highlighted the potential of these plant products in the synthesis of different metallic nanomaterials and their antimicrobial capacity. Furthermore, we correlated the extract’s role in antimicrobial activity, considering the potential synergy between molecules from the plant product and the different metallic forms associated with nanomaterials.

Chemical Characterization and Bioaccessibility Assessment of Bioactive Compounds from Umbu (Spondias tuberosa A.) Fruit Peel and Pulp Flours

Umbu, a common fruit from the northeastern region of Brazil, contains many bioactive compounds not yet exploited. Thus, this study evaluated the potential of pulps and peels of mature and semi-mature umbu as a source of bioactive compounds. Trigonelline contents ranged from 1.75 to 6.14 mg/100 g, values higher than those of many vegetables described in the literature, such as corn and barley. The contents of extractable and non-extractable phenolic compounds were also higher than those of other vegetables. Bioaccessibility of total extractable phenolics, flavonoids, and tannins was determined (15.67–37.73%, 31.87–39.10% and 18.81–114.27%, respectively). The constituent polysaccharides of the pulp and peel were tentatively chemically characterized as arabinoxylans, arabinogalactans, rhamnoarabinogalactans, xyloglucans, and pectin of the rhamnogalacturonan type. The technological potential of peel flours was evaluated. The maturation advancement showed no significant changes in the technological properties of the flours, except for color and water solubility index. Results indicated excellent prospects for future research on umbu pulps and peels as potential sources of natural bioactive compounds.

Encapsulation of bioactive compounds from byproducts of two species of passionflowers: evaluation of the physicochemical properties and controlled release in a gastrointestinal model

This study aimed to evaluate the release of active components with antioxidant and antihypertensive capacity from encapsulated extracts of the peel and seeds of Gulupa (Passiflora edulis f. edulis) and Cholupa (Passiflora maliformis) in an in vitro gastrointestinal digestion model. Microencapsulated extracts were prepared with enzymatically modified rice starch as the encapsulating material and ethanol extracts of seeds and peel of P. edulis f. edulis and P. maliformis as encapsulated material. Microcapsule characterization was performed by scanning electron microscopy with values of 4.54-5.13 μm and ξ potential values of -6.34 mV and -6.66 mV. Dynamic light scattering (DLS) analysis was conducted with polydispersion values from 1.33 to 1.51, and dispersion stability analysis was also conducted. The total phenol content and antioxidant activities (ABTS, DPPH, and FRAP) and ACE inhibitory activity (in vitro antihypertensive activity) were evaluated after each stage of digestion, with values greater than 80% of activity before gastrointestinal transit and with values greater than 55% activity after the end of gastrointestinal transit. Gastrointestinal evaluation of the encapsulated extracts was performed with an ex vivo model using pig intestines and simulating the conditions of digestion in three phases: the gastric (pH 2.0 with 1.0 M HCl +0.5 g/L pepsin), enteric (pH 8.0 with Krebs solution +1.0 mL/L bile) and final enteric (pH 7.5 Krebs solution only) phases. The microencapsulation of passionflower extracts showed good behavior against changes in pH and enzymatic activities throughout digestion, thus promoting a controlled release and targeted delivery of bioactive compounds, undergoing a paracellular mechanism through the intestinal barrier to preserve the antioxidant activity and ACE inhibitory that was shown by the extracts before encapsulation of the material.

Biopharmaceutical Evaluation of Capsules with Lyophilized Apple Powder

Apples are an important source of biologically active compounds. Consequently, we decided to model hard gelatin capsules with lyophilized apple powder by using different excipients and to evaluate the release kinetics of phenolic compounds. The apple slices of "Ligol" cultivar were immediately frozen in a freezer (at -35°C) with air circulation and were lyophilized with a sublimator at the pressure of 0.01 mbar (condenser temperature, -85°C). Lyophilized apple powder was used as an active substance filled into hard gelatin capsules. We conducted capsule disintegration and dissolution tests to evaluate the quality of apple lyophilizate-containing capsules of different encapsulating content. Individual phenolic compounds can be arranged in the following descending order according to the amount released from the capsules of different compositions: chlorogenic acid > rutin > avicularin > hyperoside > phloridzin > quercitrin > (-)-epicatechin > isoquercitrin. Chlorogenic acid was the compound that was released in the highest amounts from capsules of different encapsulating content: its released amounts ranged from 68.4 to 640.3 μg/mL. According to the obtained data, when hypromellose content ranged from 29% to 41% of the capsule mass, the capsules disintegrated within less than 30 min, and such amounts of hypromellose did not prolong the release of phenolic compounds. Based on the results of the dissolution test, the capsules can be classified as fast-dissolving preparations, as more than 85% of the active substances were released within 30 min.

Profile of bioactive compounds in pequi (Caryocar brasilense Camb.) peel flours

The bioactive compounds of pequi peel flours were characterized. Flavonoid contents ranged from 19.67 to 87.61 mg/100 g, high in comparison to many vegetables described in the literature. Gallic acid (11.52-418.67 mg/100 g), gallate ethyl (2026.75 - 5205.90 mg/100 g), ellagic acid (509.47 - 1630.66 mg/100 g), lutein (0.17-1.36 mg/100 g), β-carotene (0.82 - 1.49 mg/100 g), and β-cryptoxanthin (0.07 - 0.11 mg/100 g) were identified by HPLC, contributing to a greater valorization of the pequi peel flours. Phytochemical tests indicated the presence of hydrolyzable tannins and saponins. The detection of these compounds makes the product commercially attractive, in addition to generating value for an agro-industrial residue. The results obtained in this study confirm the multifunctional potential of pequi peel flour as a functional ingredient.

Bulk industrial fruit fibres. Characterization and prevalence of the original fruit metabolites

Here we analysed the content of primary and secondary metabolites in nine types of industrially processed fibres derived from the juice industry. Specifically, we examined fibre from: apple, peach, and pear, as non-citrus fruits; the peel and flesh of orange and tangerine, and lemon flesh, as citrus fruits; and carrot, as vegetable. Regarding primary metabolites, the sugar content ranged from 21.6 mg/g in lemon to 290 mg/g in orange peel and lower mass organic acid content ranged from 25.0 mg/g in pear to 250 mg/g in lemon. The content of fatty acids were constant during fibre processing, ranging from 0.5 to 1.46%. Furthermore, the fatty acid profile was not affect for the processing. Concerning secondary metabolites, industrial processing did not decrease the sterols content, which ranged from 0.51 to 1.66 μg/g. Regarding carotenoids, of note was the presence of epoxycarotenoids, which may reflect the quality of the industrial process, thus giving added value to the by-product.

Volatile Composition and Enantioselective Analysis of Chiral Terpenoids of Nine Fruit and Vegetable Fibres Resulting from Juice Industry By-Products

Fruit and vegetable fibres resulting as by-products of the fruit juice industry have won popularity because they can be valorised as food ingredients. In this regard, bioactive compounds have already been studied but little attention has been paid to their remaining volatiles. Considering all the samples, 57 volatiles were identified. Composition greatly differed between citrus and noncitrus fibres. The former presented over 90% of terpenoids, with limonene being the most abundant and ranging from 52.7% in lemon to 94.0% in tangerine flesh. Noncitrus fibres showed more variable compositions, with the predominant classes being aldehydes in apple (57.5%) and peach (69.7%), esters (54.0%) in pear, and terpenoids (35.3%) in carrot fibres. In addition, enantioselective analysis of some of the chiral terpenoids present in the fibre revealed that the enantiomeric ratio for selected compounds was similar to the corresponding volatile composition of raw fruits and vegetables and some derivatives, with the exception of terpinen-4-ol andα-terpineol, which showed variation, probably due to the drying process. The processing to which fruit residues were submitted produced fibres with low volatile content for noncitrus products. Otherwise, citrus fibres analysed still presented a high volatile composition when compared with noncitrus ones.

Polyphenols: Extraction Methods, Antioxidative Action, Bioavailability and Anticarcinogenic Effects

Being secondary plant metabolites, polyphenols represent a large and diverse group of substances abundantly present in a majority of fruits, herbs and vegetables. The current contribution is focused on their bioavailability, antioxidative and anticarcinogenic properties. An overview of extraction methods is also given, with supercritical fluid extraction highlighted as a promising eco-friendly alternative providing exceptional separation and protection from degradation of unstable polyphenols. The protective role of polyphenols against reactive oxygen and nitrogen species, UV light, plant pathogens, parasites and predators results in several beneficial biological activities giving rise to prophylaxis or possibly even to a cure for several prevailing human diseases, especially various cancer types. Omnipresence, specificity of the response and the absence of or low toxicity are crucial advantages of polyphenols as anticancer agents. The main problem represents their low bioavailability and rapid metabolism. One of the promising solutions lies in nanoformulation of polyphenols that prevents their degradation and thus enables significantly higher concentrations to reach the target cells. Another, more practiced, solution is the use of mixtures of various polyphenols that bring synergistic effects, resulting in lowering of the required therapeutic dose and in multitargeted action. The combination of polyphenols with existing drugs and therapies also shows promising results and significantly reduces their toxicity.

Injection-port derivatization coupled to GC-MS/MS for the analysis of glycosylated and non-glycosylated polyphenols in fruit samples

Polyphenols, including glycosylated polyphenols, were analyzed via a procedure based on injection-port derivatization coupled to gas chromatography-tandem mass spectrometry (GC-MS/MS). The polyphenols in lyophilized fruit samples were extracted with an acidified MeOH mixture assisted by ultrasound. Samples were dried under vacuum, and carbonyl groups were protected with methoxylamine. Free hydroxyl groups were subsequently silylated in-port. Mass fragmentations of 17 polyphenol and glycosylated polyphenol standards were examined using Multiple Reaction Monitoring (MRM) as the acquisition mode. Furthermore, in-port derivatization was optimized in terms of optimal injection port temperature, derivatization time and sample: N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) volume ratio. A C18 solid-phase-extraction clean-up method was used to reduce matrix effects and injection liner degradation. Using this clean-up method, recoveries for samples spiked at 1 and 10μg/g ranged from 52% to 98%, depending on the chemical compound. Finally, the method was applied to real fruit samples containing the target compounds. The complete chromatographic runtime was 15min, which is faster than reported for recent HPLC methods able to analyze similar compounds.

Development and application of a quantitative method for determination of flavonoids in orange peel: Influence of sample pretreatment on composition

Peel, a part of the citrus rich in compounds with high-added value, constitutes the bulk of the waste generated in citrus juice industries. Flavonoids are a class of these high-added value compounds characterized by their bioactivity. In this research, a method for analysis of flavonoids, based on LC-MS/MS by using a triple quadrupole detector, has been developed and applied to the quantitative analysis of 16 flavonoids in extracts obtained by maceration of citrus peel. The parameters involved in the ionization and fragmentation of the target analytes were optimized to develop a selected reaction monitoring (SRM) method, which reported detection and quantitation limits ranging from 0.005 to 5 ng/mL and from 0.01 to 10 ng/mL, respectively. The raw materials for flavonoids extraction were fresh, oven-dried and lyophilized peel of 8 different orange varieties, and the proposed quantitation method was applied to the analysis of the obtained extracts. Evaluation of the two methods of water removal showed that lyophilization preserves the concentration of the flavonoids, while oven-dried peel presented a decrease of glycosylated flavonoids and an increase of aglycone forms.