A review of in vitro methods to evaluate the bioaccessibility of phenolic compounds in tropical fruits.

International guidelines strongly advise about the frequent and varied intake of plant in diet. In this scenario, the consumption of fruits is closely related to health benefits due to the abundant presence of bioactive substances. Accordingly, the production of tropical fruits has stood out worldwide, reaching records since the past decade. However, to ensure that phenolic substances are indeed used by the body, they need to be accessible for absorption. For this purpose, several methods are used to assess the phenomenon of bioaccessibility. We provide information on i) in vitro methods for the evaluation of the bioaccessibility of phenolic compounds in tropical fruits, including their derivatives and by-products; ii) a study performed using a semi-dynamic in vitro digestion model; iii) simulated digestion with a dialysis membrane step, polyphenol transport/uptake using cell culture, and in vitro colonic fermentation process. Although standardized static and semi-dynamic in vitro digestion methods already exist, few studies use these protocols to assess the bioaccessibility of polyphenols in tropical fruits. To guarantee that in vitro digestion assays reproduce consistent results compared to in vivo reference methods, it is essential to universalize standardized methods that allow the comparison between results, enabling the validation of in vitro digestion methods.

Chrysobalanus icaco L. fruits inhibit NADPH oxidase complex and protect DNA against doxorubicin-induced damage in Wistar male rats.

Chrysobalanus icaco L. is an underexplored plant found in tropical areas around the globe. Currently, there is no apparent information regarding the effects C. icaco fruits may exert in vivo or potential role in health promotion. This study aimed at providing evidence regarding the in vivo influence of this fruit on antigenotoxicity, antimutagenicity, and oxidative stress in rats. Male Wistar rats were treated with 100, 200, or 400 mg/kg body weight (bw)/d C. icaco fruit for 14 d. Doxorubicin (DXR, 15 mg/kg bw, ip) was used for DNA damaging and as an oxidant to generate reactive oxygen species (ROS). Genomic instability was assessed by the comet assay and micronucleus (MN) test, while antioxidant activity was determined by oxidative burst of neutrophils. Chrysobalanus icaco fruit polyphenols were quantified and characterized by high-performance liquid chromatography coupled to a diode array detector and tandem mass spectrometer (HPLC-DAD-MS/MS). The concentrations of 19 chemical elements were determined by inductively coupled plasma-mass spectroscopy (ICP-MS). Significant amounts of polyphenols, magnesium, and selenium were found in C. icaco fruit. This fruit displayed in vivo antioxidant activity against DXR-induced damage in rat peripheral blood neutrophils, antigenotoxicity in peripheral blood cells, and antimutagenicity in bone-marrow cells and peripheral blood cells. Correlation analyses between endpoints examined indicated that the mechanism underlying chemopreventive actions of C. icaco fruit was attributed to inhibition of NADPH oxidase complex manifested as low levels of DNA damage in animals exposed to DXR. Data indicate that phytochemicals and minerals in C. icaco fruit protect DNA against damage in vivo associated with their antioxidant properties.

Tamarillo (Solanum betaceum Cav.) wastes and by-products: Bioactive composition and health benefits.

Introduction: During processing, a large amount of by-products is produced from tamarillo fruits in the form of stalks, outer skins, and pomace (residual seeds and inner skins). This material is a renewable source of bioactive compounds with high economic value and positive effects on human health. Previous reviews have focused on the ethnobotanical, traditional uses, and phytochemistry of the tamarillo fruit. This report aims to compile production and cultivation data, as well as the valorization of this agro-industrial residue, green extraction methods used for extracting the bioactive compounds, and their biological activity. Method: In this study, a literature search was conducted in five scientific databases: Web of Science, ScienceDirect, Scopus, PubMed, and Google Scholar to retrieve research published in English, Spanish, or Portuguese between 2009 and 2024, which mentions the composition and extraction methods of bioactive compounds from tamarillo wastes and by-products and the health benefits associated with these compounds. The data extracted was compiled and shown in this scoping review. Results: Tamarillo wastes and by products have a rich nutritional and bioactive composition, including high protein, vitamins A and C, minerals, dietary fiber, sugars, terpenes, flavonoids, carotenoids, anthocyanins, and other phytochemicals. Green methods have been effective, yielding high amounts of these compounds while preserving their integrity. Natural polyphenols have shown antioxidant, anticholinesterase, anti-inflammatory, antimicrobial, anti-diabetic, and anti-obesity properties. The antioxidant fibers, mucilage, and pectin of the pomace contribute to improved intestinal health. Conclusion: Therefore, these wastes and by-products have potential uses as natural colorant, antioxidants, supplements, functional foods, active biobased films, and in pharmaceutical and cosmeceutical sectors due to their effective bioactive molecules. Future research should focus on the use of tamarillo by-products as a source of functional ingredients in several other formulations that are still little explored, as well as their use as a natural colorant and antioxidant. More studies are necessary on the composition-activity relationship, physiological mechanisms, and clinical response.

Amazonian palm tree fruits: From nutritional value to diversity of new food products.

The rapid growth of the world population has increased the demand for new food sources, constituting a major challenge concerning the maximum use of existing food resources. The fruits of Amazonian palm trees have excellent nutritional composition and bioactive compounds. This review highlights four fruits of Amazonian palm trees that are still little explored by the food industry: açai (Euterpe oleracea), pupunha (Bactris gasipaes), buriti (Mauritia flexuosa), and tucumã (Astrocaryum aculeatum). This paper aims to inspire new ideas for researching and developing products for the food industry. It also explores the impacts of Amazonian palm fruits on health, highlighting their role in disease prevention through their nutritional effects.

Production of Long Fermentation Bread with Jabuticaba Peel Flour Added: Technological and Functional Aspects and Impact on Glycemic and Insulinemic Responses.

The consumption of jabuticaba (Plinia cauliflora), a native Brazilian fruit, has shown promising results concerning some metabolic disorders. Therefore, studying it may aid in the development of products capable of preventing or delaying pathological conditions. The objective of the present study was to formulate a functional sourdough bread with the inclusion of jabuticaba peel flour (JPF) and to evaluate the effect on the postprandial response. The proximate composition of the JPF and bread, the stability of the antioxidant compounds after baking, and the functional activity in a clinical trial were carried out to develop the product and guarantee its quality. JPF increased the fiber content of the bread in comparison to the control from 1.0 g/100 g to 2.3-2.9 g/100 g. Also, the antioxidant capacity increased 1.35 to 3.53 times by adding JPF to the bread, as well as the total reducing capacity (1.56 to 2.67 times). The bread's shelf life was guaranteed for seven days. In the clinical trial, the consumption of control bread resulted in a glycemia peak at 30 min, remaining high until 45 min; for the JPF bread, we noticed a less prominent peak at 45 min and a decrease with less inflection until 180 min. The serum antioxidant capacity of the individuals increased after the 3 h. Although no statistical difference was observed between the groups in the satiety profile, JPF bread presented higher scores after 60 min. Furthermore, a lessened desire to eat other foods and hunger was observed after consuming JPF bread. The inclusion of JPF in the bread manufacturing process promoted a longer shelf life and increased nutritional quality.

Room temperature storage of myrtle (Eugenia gracillima Kiaersk.) tropical juice: Effects of physical and chemical preservation methods.

Tropical fruit juices produced from native fruits have been widely marketed by small agribusinesses in the Brazilian semiarid region, necessitating a deeper understanding of the impact of preservation methods on quality parameters. This study aimed to prepare myrtle (Eugenia gracillima Kiaersk.) tropical juice and investigate the effects of physical preservation (90 °C for 60 s) and chemical preservation (potassium sorbate and sodium benzoate) methods. Tropical juice formulations were evaluated after preparation and every 15 days during 60 days of storage in high-density polyethylene bottles at room temperature (25 ± 2 °C). Microbiological parameters, optical microscopy, physicochemical and bioactive parameters, antioxidant capacity, and color parameters were determined. Heat-treated tropical juice showed low counts of all microbiological parameters, but optical microscopy revealed the presence of filamentous fungi after 60 days of storage. Combined use of potassium sorbate and sodium benzoate effectively prevented the development of total yeasts and molds up to 28 days of storage. Bioactive compounds in myrtle pulp contribute to storage stability, mainly total phenolics, estimated at 855.86 mg gallic acid equivalents 100 g-1. The results suggest that it is possible to harness the economic and agroindustrial potential of E. gracillima Kiaersk. fruits for the production of tropical juices, but it is recommended that other technologies be explored, such as aseptic processing or the combined use of physical and chemical methods.

Waste and by-products as sources of lycopene, phytoene, and phytofluene - Integrative review with bibliometric analysis.

Food loss and waste are severe social, economic, and environmental issues. An example is the incorrect handling of waste or by-products used to obtain bioactive compounds, such as carotenoids. This review aimed to present a comprehensive overview of research on lycopene, phytoene, and phytofluene obtained from waste and by-products. In this study, an integrative literature approach was coupled with bibliometric analysis to provide a broad perspective of the topic. PRISMA guidelines were used to search studies in the Web of Science database systematically. Articles were included if (1) employed waste or by-products to obtain lycopene, phytoene, and phytofluene or (2) performed applications of the carotenoids previously extracted from waste sources. Two hundred and four articles were included in the study, and the prevalent theme was research on the recovery of lycopene from tomato processing. However, the scarcity of studies on colorless carotenoids (phytoene and phytofluene) was evidenced, although these are generally associated with lycopene. Different technologies were used to extract lycopene from plant matrices, with a clear current trend toward choosing environmentally friendly alternatives. Microbial production of carotenoids from various wastes is a highly competitive alternative to conventional processes. The results described here can guide future forays into the subject, especially regarding research on phytoene and phytofluene, potential and untapped sources of carotenoids from waste and by-products, and in choosing more efficient, safe, and environmentally sustainable extraction protocols.

Mycotoxins on edible insects: Should we be worried?

Edible insects are a solid alternative to meet the growing demand for animal protein. However, there are doubts regarding the safety of insect consumption. Mycotoxins are substances of concern for food safety, as they may cause harmful effects on the human organism and accumulate in the tissues of some animals. This study focuses on the characteristics of the main mycotoxins, the mitigation of human consumption of contaminated insects, and the effects of mycotoxins on insect metabolism. To date, studies reported the interaction of the mycotoxins aflatoxin B1, ochratoxin A, zearalenone, deoxynivalenol, fumonisin B1, and T-2, isolated or combined, in three insect species from Coleoptera and one from Diptera order. The use of rearing substrates with low mycotoxin contamination did not reduce the survival and development of insects. Fasting practices and replacing contaminated substrate with a decontaminated one decreased the concentration of mycotoxins in insects. There is no evidence that mycotoxins accumulate in the tissues of the insects' larvae. Coleoptera species showed high excretion capacity, while Hermetia illucens had a lower excretion capacity of ochratoxin A, zearalenone, and deoxynivalenol. Thus, a substrate with low mycotoxin contamination could be used for raising edible insects, particularly from the Coleoptera order.

Microencapsulation of anthocyanins as natural dye extracted from fruits - A systematic review.

Anthocyanins are naturally colored compounds that can be extracted from plants, especially fruits. Their molecules are unstable under normal processing conditions; thus, they must be protected using modern technologies, such as microencapsulation. For this reason, many industries are searching for information from review studies to find the conditions that improve these natural pigments' stability. This systematic review aimed to elucidate different aspects of anthocyanins, such as main extraction and microencapsulation methods, gaps in analytical techniques, and industrial optimization measurements. Initially, 179 scientific articles were retrieved, of which seven clusters were found with 10-36 cross-linked references. Sixteen articles containing 15 different botanical specimens were included in the review, most focusing on the whole fruit, pulp, or subproducts. The extraction and microencapsulation technique resulting in the highest anthocyanin content was sonication with ethanol, temperature below 40 °C, and maximum time of 30 min, followed by microencapsulation by spray drying with maltodextrin or gum Arabic. Color apps and simulation programs may help verify natural dyes' composition, characteristics, and behavior.

Oxidation of whey protein isolate after thermal convection and microwave heating and freeze-drying: Correlation among physicochemical and NIR spectroscopy analyses.

This study investigated the oxidative susceptibility of whey protein isolate (WPI) dispersions treated by microwave or thermal convection before freeze-drying. WPI (20 mg protein/mL) in distilled water (DW) was heated at 63 ± 2 °C for 30 min by microwave (WPI-MW) or convection heating (WPI-CH) and freeze-dried. Untreated WPI (WPI-C), WPI solubilized in DW and freeze-dried (WPI-FD), and WPI solubilized in DW, heated at 98 ± 2 °C for 2 min and freeze-dried (WPI-B) were also evaluated. Structural changes (turbidity, ζ potential, SDS-PAGE, and near-infrared spectroscopy (NIR)) and protein oxidation (dityrosine, protein carbonylation, and SH groups) were investigated. WPI-FD showed alterations compared to WPI-C, mainly concerning carbonyl groups. Microwave heating increased carbonyl groups and dityrosine formation compared to conventional heating. NIR spectrum indicated changes related to the formation of carbonyl groups and PCA analysis allowed us to distinguish the samples according to carbonyl group content. The results suggest that NIR may contribute to monitoring oxidative changes in proteins resulting from processing.

Green banana biomass (Musa spp.) as a natural food additive in artisanal tomato sauce.

This study aimed to prepare artisanal tomato sauce (TSC, control) containing 10% (TS10) or 20% (TS20) of whole green banana biomass (GBB). Tomato sauce formulations were evaluated for storage stability, sensory acceptability, and color and sensory parameters correlations. Data were subjected to Analysis of Variance, followed by the comparison of means by Tukey's test (p < 0.05 and p < 0.01). Correspondence analysis was used to assess the responses to a Check-All-That-Apply questionnaire. A significant effect was observed (p > 0.05) for the interaction between storage time and GBB addition on all physicochemical parameters. GBB reduced titratable acidity and total soluble solids (p < 0.05), possibly because of its high content of complex carbohydrates. All tomato sauce formulations had adequate microbiological quality for human consumption after preparation. Sauce consistency increased with increasing GBB concentrations, improving the sensory acceptance of this attribute. All formulations achieved the minimum threshold for overall acceptability (70%). A thickening effect was observed with the addition of 20% GBB, resulting in significantly (p < 0.05) higher body, higher consistency, and reduced syneresis. TS20 was described as firm, very consistent, light orange in color, and very smooth. The results support the potential of whole GBB as a natural food additive.

Trust your gut: Bioavailability and bioaccessibility of dietary compounds.

Studying the composition of a certain food is not enough to predict its health benefits. Research over the past decades has decisively strengthened the notion that any putative health benefit is best related to the fraction of compounds transferred from ingested foods into the body since the absorption may be incomplete after oral consumption. In other words, the bioavailability of food components is crucial information. Therefore, a variety of in vitro models have been developed to predict their bioaccessibility and bioavailability in the most diverse food matrices and food products. These models can also be applied to study the impact of several endogenous or exogenous factors on the bioaccessibility and bioavailability of nutrients and bioactive compounds, guiding nutrition and food scientists, technologists, and engineers towards the development of strategies to optimize the positive impact of the diet on well-being and quality of life. While bioavailability is ideally examined in human volunteers, in vitro digestion methods, as well as intestinal absorption and microphysiological models, simulate human physiological conditions. Additionally, in vitro methods are alternatives to offset ethical, economical, and experimental limitations associated with in vivo studies conducted either with individuals or animals. This graphical review draws parallels between in vitro models mimicking digestion processes, uptake, absorption, metabolism, and distribution of dietary compounds and human physiology.

The use of alternative food sources to improve health and guarantee access and food intake.

To feed and provide Food Security to all people in the world is a big challenge to be achieved with the 2030 Agenda. Undernutrition and obesity are to the opposite of a healthy nutritional status. Both conditions are associated with unbalanced nutrition, absence of food or excess of non-nutritive foods intake. These two nutritional conditions associated with food production are closely related to some goals highlighted by the United Nations in the 2030 Agenda to achieve sustainable world development. In this context, the search for alternative foods whose sustainable production and high nutritional quality guarantee regular access to food for the population must be encouraged. Alternative foods can contribute to Food Security in many ways as they contribute to the local economy and income generation. Popularizing and demystifying the uses of unconventional food plants, ancestral grains, flowers, meliponiculture products, and edible insects as sources of nutrients and non-nutrients is another challenge. Herein, we present an overview of alternative foods - some of them cultivated mostly in Brazil - that can be explored as sources of nutrients to fight hunger and malnutrition, improve food production and the economic growth of nations.

One-step rapid extraction of phytosterols from vegetable oils.

The conditions for the extraction of phytosterols (campesterol, stigmasterol and ß-sitosterol) from vegetal oils were optimized by means of response surface methodology (RSM). A 24 central composite rotatable design (CCRD) was used to investigate the effects of four independent variables: sample weight (g), saponification temperature (°C), saponification time (h) and number of extractions (n). The CCRD was carried out in 27 trials, including eight axial and three central points; and the response variables were the contents of campesterol, stigmasterol, ß-sitosterol and total phytosterols. The optimized conditions established by the RSM were 0.3 g of sample, saponification for 3 h at 50 °C and 4 extractions with n-hexane. Satisfactory values for linearity, recovery, repeatability, accuracy, precision, limits of detection (2.0-2.3 mg/100 g) and quantification (6.5-7.7 mg/100 g) were achieved. The optimized method was also validated by comparison with the official AOCS method, and the contents of stigmasterol and ß-sitosterol did not show significant differences (p > 0.05) when determined by both methods. However, low values (p < 0.05) for campesterol were found when the samples were analyzed by the AOCS method. The method optimized and validated in the present work is easy to carry out, fast and accurate. The method was successfully applied to sunflower, canola, corn, soybean and olive oils, and the lowest contents of total phytosterols were found in olive oil while and the highest amounts, in corn oil.

Marigold carotenoids: Much more than lutein esters.

Carotenoids constitute a large group of lipophilic pigments whose health-promoting benefits have been widely recognized. Hydroxy-containing carotenoids can be found in both free form or esterified with fatty acids in several plant matrices, but the native carotenoid profile is overall poorly explored due to the difficulty of analyzing carotenoid esters. One of the main natural sources of carotenoids is the marigold flower, which has been extensively used by the industry for the production of food colorants or supplements, both often manufactured with no saponification process. Although lutein esters are well established as the major compounds naturally found in marigold petals and their products, carotenoid esters other than the lutein ones have not been extensively examined. We carried out a comprehensive identification of carotenoids and carotenoid esters from marigold petals by LC-DAD-(APCI+)MS/MS. Whereas 18 carotenoids were identified in the saponified extract, 56 were identified when no saponification procedure was carried out: 6 free carotenoids, 20 monoesters and 30 diesters. This is the first time that esters of zeaxanthin, violaxanthin, auroxanthin, zeinoxanthin and ß-cryptoxanthin are identified in marigold. The structural information obtained through characteristic fragmentation patterns and diagnostic fragments in MS and MS/MS spectra (APCI+) sustained the differentiation between carotenoid esters with similar characteristics. Therefore, the separation of carotenoids by reversed-phase liquid chromatography using C30 columns in combination with DAD and APCI-MS/MS detection allowed high sensitivity and selectivity for carotenoid ester analysis.

Fat reduction and whey protein concentrate addition alter the concentration of volatile compounds during Prato cheese ripening.

The impact of fat reduction and the addition of whey protein concentrate (WPC) on the volatile compounds profile of Prato cheese was evaluated for 210 days of storage at 12 °C. Full fatPrato cheese, Prato cheese with fat reduction and reduced fatPrato cheese with 0.5% (w/v) WPC were made, and replicated on a different day. Cheese volatile compounds were extracted by solid phase microextraction (SPME) and separated, identified and quantified by gas chromatography coupled to a mass spectrometry detector (GC-MS). Fat reduction and the WPC addition resulted in lower concentrations of compounds derived from lipolysis and free fatty acid catabolism. Fat reduction generated higher levels of diacetyl and acetoin, both from the citrate metabolism, at days 5 and 30. A similar pattern was observed for sulfur compounds derived from the catabolism of free amino acids, at day 120. Higher levels of diacetyl (day15), dimethyl disulfide (days 150-180) and dimethyl trisulphide (days 150-210) were found for cheese with WPC. These differences might have occurred due to alterations in the structure and polarity of the protein matrix caused by fat reduction and the WPC addition.

Purple pitanga fruit (Eugenia uniflora L.) protects against oxidative stress and increase the lifespan in Caenorhabditis elegans via the DAF-16/FOXO pathway.

Pitanga, a fruit of the pitangueira tree (Eugenia uniflora L.), is native to Brazil and has a high antioxidant capacity due to the elevated amount of anthocyanins. The present study aimed to investigate the chemical composition of the purple pitanga fruit and to evaluate its antioxidant effect in the nematode Caenorhabditis elegans. We observed that the ethanolic extract of purple pitanga did not cause any toxic effects but notably increased worm lifespan. The extract improved the survival, reproduction and lifespan of the worms in pre- and post-exposure to stressors H2O2 and juglone, as well as improved the lifespan of the oxidative stress hypersensitive strain mev-1. Notably, PPE extract decreased reactive oxygen species by DCF-DA probe and protein carbonyl content from worms stressed with H2O2. The extract also affected the expression of superoxide dismutase SOD-3 and heat shock protein HSP-16.2 levels, daf 16 target genes that modulate lifespan and antioxidant metabolism. In addition, we demonstrate that these effects are dependent on DAF-16, as PPE extract did not provide protection in daf-16 mutants. Therefore, these results suggest that PPE significantly protected against oxidative stress modulating daf-16 target genes.

Carotenoid esters in foods - A review and practical directions on analysis and occurrence.

Carotenoids are naturally found in both free form and esterified with fatty acids in most fruits and some vegetables; however, up to now the great majority of studies presents data on carotenoid composition only after saponification. The reasons for this approach are that a single xanthophyll can be esterified with several different fatty acids, generating a great number of different compounds with similar chemical and structural characteristics, thus, increasing the complexity of analysis compared to the respective saponified extract. This means that since UV/Vis spectrum does not change due to esterification, differentiation between free and acylated xanthophylls is dependent at least on elution order and mass spectrometry (MS) features. The presence of interfering compounds, especially triacylglycerides (TAGs), in the non-saponified extract of carotenoids can also impair carotenoid ester analyses by MS due to high background noise and ionization suppression since TAGs can be present in much higher concentrations than the carotenoid esters. This leads to the need of development of new and effective clean-up procedures to remove the potential interferents. In addition, only few standards of xanthophyll esters are commercially available, making identification and quantification of such compounds even more difficult. Xanthophyll esterification may also alter some properties of these compounds, including solubility, thermostability and bioavailability. Considering that commonly consumed foods are dietary sources of xanthophyll esters and that it is the actual form of ingestion of such compounds, an increasing interest on the native carotenoid composition of foods is observed nowadays. This review presents a compilation of the current available information about xanthophyll ester analyses and occurrence and a practical guide for extraction, pre-chromatographic procedures, separation and identification by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Two-step cleanup procedure for the identification of carotenoid esters by liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry.

Carotenoids are naturally found in both free form and esterified with fatty acids in most fruits; however, up to now the great majority of studies only evaluated their composition after saponification. This fact is easily explained by the difficult to analyze carotenoid esters. Preliminary studies showed that cleanup procedures in the extract are necessary for further analysis by LC-MS/MS since triacylglycerols (TAGs) impair the MS detection. Considering these facts, we developed a new cleanup procedure to remove TAGs and other lipids from carotenoid fruit extracts. This procedure is based on physical removal of solid lipids at low temperature followed by open column chromatography on MgO and diatomaceous earth. Before cleanup, four carotenoid diesters and two free xanthophylls were identified in murici (Byrsonyma crassifolia), corresponding to about 65% of the total chromatogram area. After carrying out the two-step cleanup procedure, 35 carotenoids were identified, being 14 monoesters, six free carotenoids and 15 carotenoid diesters. We can conclude that this two-step procedure was successfully applied to murici, an Amazonian fruit, which contains high amounts of lipids.