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A high daily intake of fruits and vegetables is an important strategy to promote health. The mechanism explaining the health benefits of plant food materials is attributed, at least in part, to their high content of bioactive phenolics. Guarana (Paullinia cupana) is a typical product from Amazon biota and, mainly as a source of caffeine; its seeds are commonly used as stimulants. However, guarana seeds are also rich in catechin, epicatechin, procyanidin B1, and procyanidin B2. Guarana exhibits potential health benefits in cognitive function and prevention of cardiovascular disease. Furthermore, it is a promising source of antihyperglycemic and antibacterial compounds for prevention and/or management of type 2 diabetes and oral diseases. However, to confirm these benefits in humans, clinical trials are needed to provide evidence to support these anecdotal observations.
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Copyright: © 2019 International Society for Nutraceuticals and Functional Foods.
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Opinion J. Food Bioact. 2019;6:1–5
Journal of
Food Bioactives International Society for
Nutraceuticals and Functional Foods
Guarana as a source of bioactive compounds
Cintia Pereira Silvaa*, Rosana Aparecida Manólio Soares-Freitasa, Geni Rodrigues Sampaioa,
Adriano Costa de Camargoa,b* and Elizabeth Aparecida Ferraz Silva Torresa
aNutrition Department, School of Public Health, University of São Paulo – USP, São Paulo, Brazil
bDepartamento de Ciencias Vegetales, Facultad de Agronomía e Ingeniería Forestal, Ponticia Universidad Católica de Chile, Casilla 306-
22, Santiago, Chile
*Corresponding author: Cintia Pereira Silva and Adriano Costa de Camargo, Nutrition Department, School of Public Health, University
of São Paulo – USP, São Paulo, Brazil. E-mail:,
DOI: 10.31665/JFB.2019.6182
Received: June 18, 2019; Revised received & accepted: June 26, 2019
Citation: da Silva, C.P., Soares-Freitas, R.A.M., Sampaio, G.R, de Camargo, A.C, and Torres, E.A.F.S. (2019). Guarana as a source of
bioactive compounds. J. Food Bioact. 6: 1–5.
A high daily intake of fruits and vegetables is an important strategy to promote health. The mechanism explain-
ing the health benets of plant food materials is aributed, at least in part, to their high content of bioacve
phenolics. Guarana (Paullinia cupana) is a typical product from Amazon biota and, mainly as a source of caeine;
its seeds are commonly used as smulants. However, guarana seeds are also rich in catechin, epicatechin, procya-
nidin B1, and procyanidin B2. Guarana exhibits potenal health benets in cognive funcon and prevenon of
cardiovascular disease. Furthermore, it is a promising source of anhyperglycemic and anbacterial compounds
for prevenon and/or management of type 2 diabetes and oral diseases. However, to conrm these benets in
humans, clinical trials are needed to provide evidence for these anecdotal observaons.
Keywords: Caeine; Phenolic compounds; Antioxidant properties; Anti-Inammatory potential; Antimicrobial activity.
Non-communicable diseases (NCDs) are the major health chal-
lenges of the 21st century. In 2016, they were responsible for 71%
(41 million) death around the globe. NCDs include cardiovascular
diseases (17.9 million death), cancers (9 million death), chronic
respiratory diseases (3.8 million death), and diabetes (1.6 million
death) (WHO, 2018).
Unhealthy diet is a behavioral risk factor linked to the main
NCDs. However, several studies have shown that a high daily in-
take of vegetables and fruits may be helpful in health promotion.
The mechanisms explaining these health benets are related to the
action of bioactive molecules such as phenolic compounds (Boe-
ing et al., 2012; Abbas et al., 2017; Karasawa and Mohan, 2018),
mainly due to their antioxidant potential.
Guarana (Paullinia cupana) is a typical product from Amazon
biota. As a source of caeine, its seeds are commonly used as a
stimulant. In food processing, guarana seed extract is the base a-
vor used in the manufacture of one of the most popular Brazilian
carbonated drinks. Furthermore, it is also used in the energy drink
industry. Besides that, guarana has been listed in the Brazilian
Pharmacopoeia (Agência Nacional de Vigilância Sanitária, 2017)
and is also introduced in the U.S. Pharmacopeia, under mono-
graphs for guarana seed, its powder and dry extract. The Brazilian
Food Supplement Law recently recognized that guarana presents
bioactive substances, hence supporting its role as a functional food
ingredient (Agência Nacional de Vigilância Sanitária, 2018).
Literature data show that guarana seeds are good sources of cat-
echin, epicatechin, procyanidin B1, procyanidin B2 (Schimpl et
al., 2013; Yonekura et al., 2016). Due to its bioactive compounds,
guarana has attracted considerable interest as an ingredient for the
development of functional foods and food supplements. However,
the health benets of bioactive compounds depend not only on the
intake levels but also on their bioavailability (BAv). The bioavaila-
bility is involved with digestion, absorption, metabolism, distribu-
tion, transporting, excretion, and colonic fermentation. Therefore,
these parameters have to be considered (de Camargo et al., 2018;
Shahidi and Peng, 2018; Shahidi et al., 2019).
In vitro methods to simulate gastrointestinal digestion allow de-
termination of the bioaccessibility (BAcs) of bioactive compounds
Journal of Food Bioactives | www.isn
Guarana as a source of bioactive compounds da Silva et al.
and evaluate the eect of food processing and to anticipate their
action under systemic conditions. In line with this, recent studies
have suggested the use of gastrointestinal digestion in functional
food design (Cilla et al., 2018; Santana and Macedo, 2018).
Yonekura et al. (2016) have shown BAcs and BAv of phenolic
compounds of guarana seed in their in vivo study. Mendes et al.
(2019) evaluated the eect of macronutrients (milk casein, potato
starch and vegetable oil) on BAcs of guarana catechins in Caco-2
cells. The results demonstrated that the interaction with other food
macronutrients did not aect the permeability values of all tested
Guarana consumption may induce changes in lipid metabolism.
Krewer et al. (2011) evaluated the associations of metabolic dis-
orders and anthropometric and biochemical biomarkers of lipid,
glucose and oxidative metabolism and the habitual ingestion of
guarana by an elderly population. The reduction of prevalence of
various metabolic disorders (hypertension, obesity and metabolic
syndrome) was associated with guarana ingestion, thus suggest-
ing a potential protective eect of regular consumption of guarana
ingestion against metabolic disorders.
Oxidation of low-density lipoprotein-cholesterol (LDL-c) is
known as a biomarker related to the development of coronary heart
disease (Amarowicz, 2016). To investigate how guarana consump-
tion protects against metabolic disorders, Portella et al. (2013) car-
ried out an in vivo study to better understand the potential eects of
guarana on LDL-c oxidation. Healthy elderly subjects who habitu-
ally ingested guarana demonstrated lower LDL-c oxidation than
that of the control group (reduction of 27%, p < 0.0014). Further-
more, guarana exhibited a high antioxidant activity in vitro, mainly
at concentrations of 1 and 5 μg/mL, as demonstrated by decreased
values of conjugated dienes (CDs) and thiobarbituric acid reactive
substances (TBARS), tryptophan destruction and high total per-
oxyl radical-trapping potential (TRAP) activity.
Many studies suggest the link between the intake of dietary an-
tioxidants and the reduction/prevention of cardiovascular diseases
(CVD) (Chiu et al., 2018). The impact of these antioxidants stems
from their protection towards LDL-c oxidation, which is recog-
nized by its role in the early atherogenic process (Vauzour et al.,
2010; Billingsley and Carbone, 2018).
Yonekura et al. (2016) assessed the eects of guarana consump-
tion on plasma catechins, erythrocyte antioxidant enzyme activity
(superoxide dismutase, catalase, and glutathione peroxidase) and
biomarkers of oxidative stress (ex vivo LDL-c oxidation, plasma
total antioxidant status and oxygen radical absorbance capacity
(ORAC) values, and lymphocyte single cell gel electrophoresis) in
healthy overweight subjects. These authors showed that daily in-
take of guarana had both acute and cumulative eects on GPx (glu-
tathione peroxidase) and catalase, which are phase II antioxidant
enzymes that reduce peroxides to water molecules. However, the
antioxidant status markers such as reducing ex vivo LDL-c oxida-
tion and hydrogen peroxide-induced DNA damage in lymphocytes
improved only transiently. The authors believe that the daily dose
of guarana was probably not enough to keep the fasting plasma
catechin concentration above a threshold level required to exert
direct antioxidant eects.
The anti-hyperglycemic potential of guarana seed consumption
has been pointed as another important health benet. The aque-
ous extract of guarana seeds was able to inhibit α-glucosidase
and α-amylase activities in vitro (Silva et al., 2018). Studies have
shown that catechins exhibit α-glucosidase and α- amylase inhibi-
tory activities (Cires et al., 2017; Hanhineva et al., 2010; Kim et
al., 2016). Therefore, to conrm this hypothesis, further studies
with guarana are warranted.
Gut microbiome is involved in the etiology of obesity and obe-
sity-related complications such as non-alcoholic fatty liver disease
(NAFLD), insulin resistance and type 2 diabetes mellitus (T2DM).
The main species of the colonic microbiota are the genera Bac-
teroides, Bidobacterium, Ruminococcus, Eubacterium and Lac-
tobacillus (Canfora et al., 2019). Silveira et al. (2018) evaluated
the eects of guarana seed powder (GSP) on gut microbial com-
position in Wistar rats after 21 days of treatment. GSP altered gut
microbiota in a negative way, loss in diversity, decreased Bacte-
roidetes and increased Cyanobacteria abundance, probably due
to other metabolites than caeine. The modulation of gut micro-
biota by polyphenols is not fully understood. Human intervention
studies provide the best models for studying the eect of phenolic
compounds on modulation of gut microbiota. However, human in-
tervention studies hold inevitable practical and ethical limitations
(Ozdal et al.,2016).
Several phenolic compounds (e.g. catechins and proanthocyani-
dins) have been recognized as potential antimicrobial agents with
bacteriostatic or bactericidal actions (de Camargo et al., 2017;
Ozdal et al., 2016). Majhenič et al. (2007) tested guarana seed
extracts against three food-borne fungi: Aspergillus niger, Tri-
choderma viride and Penicillium cyclopium, and three pathogenic
bacteria: Escherichia coli, Pseudomonas uorescens and Bacillus
cereus. The results suggested that seed extracts of guarana possess
strong antimicrobial action. Besides that, in vitro assessment of the
antibacterial potential of the guarana extracts against Streptococ-
cus mutans showed that these could be used in the prevention of
bacterial dental plaque (Yamaguti-Sasaki et al.,2007).
Numerous plant extracts such as guarana have shown the ability
to prevent carcinogenesis by reducing tumor size or relieve cancer-
related symptoms. Fukumasu et al. (2008) evaluated the eects of
guarana in an experimental metastasis model. Cultured B16/F10
melanoma cells (5 × 105 cells/animal) were injected into the tail
vein of mice on the 7th day of guarana treatment (2.0 mg·g–1 body
weight, per gavage) and the animals were treated with guarana
daily up to 14 days until euthanasia (total treatment time: 21 days).
Guarana treatment decreased proliferation and increased apoptosis
of tumor cells, consequently reducing the tumor burden area.
Hertz et al. (2015) evaluated the eects of guarana on breast
cancer cell response to 7 chemotherapeutic agents currently used
in the treatment of breast cancer. MCF-7 breast cancer cells were
cultured under controlled conditions and exposed to 1, 5 and 10
μg.mL–1 guarana concentrations, with and without chemothera-
peutics (gemcitabine, vinorelbine, methotrexate, 5-uorouracil,
paclitaxel, doxorubicin and cyclophosphamide). The main results
demonstrated the antiproliferative eect of guarana at concentra-
tions of 5 and 10 μg.mL–1 and a signicant eect on chemothera-
peutic drug action.
Cadoná et al. (2017) investigated the in vitro antitumor eect
of guarana by inhibiting the AKT/mTOR/S6K and MAPKs path-
ways. Colorectal and breast cancer cell lineages, HT-29 and MCF-
7 cells, respectively, were exposed to dierent guarana concentra-
tions (0.1, 1, 10, and 100 μg. mL–1) as well as its main bioactive
molecule, caeine, at proportional concentrations to those found
in the extract. The results showed that guarana could serve as an
important agent in antitumor pharmacologic therapies by inhibit-
ing mTOR and MAPKs pathways. However, the most published
studies are in vitro so it is necessary to explore novel ways to ex-
trapolate the overwhelming benecial evidence seen in pre-clinical
studies to humans Table 1.
Increasing evidence suggests that ingested food polyphenols
can have benecial eects in neuronal protection by acting against
oxidative stress and inammatory injury (Ashafaq et al., 2012; de
Camargo et al., 2019; John and Shahidi, 2019; Wang et al., 2018;
Zhang and Tsao, 2016; Zhang et al., 2018). Moreover, polyphenols
Journal of Food Bioactives | www.isn 3
Silva et al. Guarana as a source of bioactive compounds
have been reported to promote cognitive functions (Filosa et al.,
2018). A double-blind, randomised, placebo-controlled, parallel
groups study assessed the acute eects of either a vitamin/min-
eral/guarana supplement or placebo drink in 129 healthy young
adults (18–24 years). Participants completed a 10 min version of
the Cognitive Demand Battery. Thirty minutes following their
drink participants made six consecutive completions of the battery
(i.e. 60 min). The vitamin/mineral/guarana combination resulted
in improved task performance, in comparison to placebo and the
increase in mental fatigue associated with extended task perfor-
mance was also attenuated by the supplement (Kennedy et al.,
2008). Scholey et al. (2013) also conrmed the acute benets of
multivitamins with guarana on mood and cognitive performance.
It is, however, not fully understood which bioactive compound
of guarana improves the mental health. Probably the eect of guar-
ana is due to its caeine content (Scholey et al., 2013). Adeno-
sine seems to inhibit the release of many neurotransmitters in the
central nervous system such as serotonin, noradrenaline and dopa-
mine. Therefore, adenosine receptor antagonists, such as caeine,
promote the release of these various neurotransmitters (Mclellan
et al., 2016; Kolahdouzan and Hamadeh, 2017). However, animal
studies suggest that the powerful neuroprotective eects are due
phenolic compounds content (chlorogenic acid, epigallocatechin
gallate, curcumin, tannins). Their mode of action range from pro-
tection against oxidative stress to interaction with signaling path-
ways involved in maintaining energy homeostasis (Kennedy et al.,
2008; Gomez-Pinilla and Nguyen, 2012).
Globally, depression is rising in an alarming manner, in almost
every community of the world. The pathophysiology of depression
is very complex, but the literature has shown the involvement of
brain-derived neurotrophic factor (BDNF) as a crucial biomarker
of this neural disorder. Some studies with phenolic compounds
from blueberry and grape have shown that phenolic compounds
are able to modulate important marker in brain tissue and could be
an important factor to prevent brain diseases (Williams et al; 2008;
Gomez-Pinilla and Nguyen, 2012; Dani et al., 2017). Therefore,
further studies with guarana should investigate its role in modula-
tion of BDNF.
In summary, this contribution shows that the potential health
benets of guarana go beyond the action of caeine. Prevention of
Table 1. Studies in vitro or in vivo about health eects of guarana
Health eects In vitro/in vivo Dose References
Eects on metabolic comorbidies
(obesity, hypertension, type 2
diabetes, and metabolic syndrome)
In vivo: elderly humans Twice or more mes a week Krewer et al. (2011)
Oxidave stress and metabolic
disorders (eects on the
oxidaon of LDL-c)
In vivo: blood samples
of elderly humans; In
vitro: isolated LDL-c
In vivo: at least 5 mes per week In
vitro: 0.05, 0.1,0.5,1, and 5 µg·mL−1;
Portella et al. (2013)
Oxidave stress In vivo: overweight
humans; Ex vivo: oxidaon
of LDL-c and total plasma
anoxidant capacity
In vivo: 3 g of the powder diluted
in 300 ml of water before intake,
daily for 15 days before breakfast
Yonekura et al. (2016)
Anhyperglycemic In vitro: inhibion of acvity
of carbohydrate-hydrolyzing
enzymes (α-amilase
and α-glucosidase)
Guarana extracts aer in vitro
digeson α-amilase: 0.315,
0.525 and 0.875 mg·mL−1);
α-glucosidase: 0.4 and 0.8 mg·mL−1
Silva et al. (2018)
Gut microbial composion and redox
and inammatory parameters
In vivo: Wistar rats Guarana seed powder the major
compounds are caeine (34.19
± 1.26 mg·g−1), theobromine
(0.14 ± 0.01 mg·g−1), (+)- catechin
(3.76 ± 0.12 mg·g−1), and
(−)-epicatechin (4.05 ± 0.16 mg·g−1)
Silveira et al. (2018)
Anmicrobial acvity In vitro: anbacterial potenal
of the guarana extracts against
Streptococcus mutans
The aqueous extract (AqE) from
the 5% (w/v) guarana seeds;
crude (EBPC) extracts and semi-
puried (EPA and EPB) fracons
et al. (2007)
Cognive performance
and mental fague
In vivo: healthy young adults vitamin/mineral/guarana
Kennedy et al. (2008)
Mood, cognive performance
and funconal brain acvaon
In vivo: healthy young adults vitamin/mineral/guarana
Scholey et al. (2013)
Anproliferave eect In vitro: breast cancer
cells MCF-7
Guarana extracts 1, 5
and 10 µg·mL−1
Hertz et al. ( 2015)
Ancancer eect In vivo: female C57Bl/6 mice 2.0 mg·g−1 body weight Fukumasu et al. (2008)
Antumor eect In vitro: Colorectal and
breast cancer cell lineages
HT-29 and MCF-7 cells
0.1, 1, 10, and 100 µg·mL−1 Cadoná et al. (2017)
Journal of Food Bioactives | www.isn
Guarana as a source of bioactive compounds da Silva et al.
cardiovascular diseases and benets on cognitive performance re-
lated to phenolics from guarana have been reported. Besides that,
due to their inhibitory eect towards α-glucosidase and α-amylase,
its promising action as a new antihyperglycemic agent for preven-
tion and/or management of type 2 diabetes has been highlighted.
Finally, as antibacterial ingredient, phenolic bioactives from guar-
ana may counteract oral diseases (plaque and periodontal diseas-
es). However, to conrm the benets of guarana in humans, these
evidences must be further addressed in clinical trials.
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... Previously in the same century, German botanist Theodore von Martius identified and isolated caffeine from the composition of guarana (Breitbach et al., 2013;Schimpl et al., 2013). Accordingly, many scientific studies using guarana have focused on health effects associated with caffeine, such as cognitive and stimulant effects (Silva, Soares-Freitas, Sampaio, et al., 2019). Other studies have indicated that guarana's benefits to human health originate from a complex synergistic effect among its various components rather than caffeine alone (Haskell et al., 2007;Kennedy et al., 2004;Ruchel et al., 2016). ...
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Guarana (Paullinia cupana) is a plant from the Amazon region with cultural importance. Despite its early ancestral use by indigenous tribes, the first reports regarding the benefits of guarana consumption for human health were published in the 19th century. Since then, the use of guarana seed in powder and extract forms has been studied for its diverse effects on human health, such as stimulating, anti-inflammatory, antioxidant, anticancer, hypocholesterolemic, and anti-obesity effects. These effects are attributed to the high content of bioactive compounds found in guarana seeds, especially methylxanthines and flavonoids. In fact, the Brazilian Food Supplement Law has officially acknowledged guarana as a source of bioactive compounds. The number and diversity of studies focused on guarana and human health are increasing; thus, organizing and describing the available evidence on guarana and its applications is necessary to provide a framework for future studies. In this narrative review, we have organized the available information regarding guarana and its potential effects on human health. Guarana produces unique fruits with great potential for human health applications. However, the available evidence lacks human studies and mechanistic investigations. Future studies should be designed considering its applicability to human health, including intake levels and toxicity studies.
... Flavan-3-ols have the strongest ROS scavenging capacity among flavonoids and can protect the body from oxidative damages (Panche, Diwan & Chandra, 2016). Other sources of bioactive catechins and procyanidins include green tea and guarana (Li et al., 2019;Pinaffi et al., 2020;Silva et al., 2019). The Brazilian legislation already contemplates a natural source (cranberry) of proanthocyanidins for industrial application (de Camargo and Lima, 2019). ...
Agro-industrial activities generate large amounts of solid residues, which are generally discarded or used as animal feed. Interestingly, some of these by-products could serve as natural sources of bioactive compounds with great potential for industrial exploitation. This study aimed to optimize the extraction of phenolic antioxidants from the pulp residue (oil processing by-product) of inajá (Maximiliana maripa, a native species found in the Brazilian Amazon). The antioxidant properties of the optimized extract and its phenolic profile by high-resolution mass spectrometry (LC-ESI-QTOF-MS) were further determined. Central composite rotatable design and statistical analysis demonstrated that the temperature of 70°C and 50% (v/v) ethanol concentration improved the extraction of phenolic compounds with antioxidant properties. The optimized extract also showed scavenging activity against the ABTS radical cation and reactive oxygen species (ROS; peroxyl and superoxide radical, and hypochlorous acid). Moreover, the optimized extract was able to reduce NF-κB activation and TNF-α release, which are modulated by ROS. Flavan-3-ols were the major phenolics present in the optimized extract. Collectively, our findings support the use of inajá cake as a new source of bioactive catechins and procyanidins. This innovative approach adds value to this agro-industrial by-product in the functional food, nutraceutical, pharmaceutical, and/or cosmetic industries and complies with the circular economy agenda.
... Polyphenols bind proteins due to the formation of hydrogen bonds or addition of nucleophiles to oxidized phenolics as quinones and specific methods have been developed for discovering new enzyme inhibitors aiming at designing new functional foods and/or nutraceuticals [65]. Accordingly, several sources of phenolic compounds have been tested for their inhibitory activity toward alpha-glucosidase [66,67]. The antidiabetic effect of natural compounds has been in the spotlight of various researchers [68,69]. ...
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A clear gap with respect to the potential biological properties of wheat flavonoids exists in the available literature. This information is crucial for breeding programs aiming to produce new varieties presenting improved health benefits. Accordingly, advanced breeding lines of whole durum wheat were evaluated in this contribution. The highest recovery of phenolics was achieved using aqueous acetone (50:50, v/v), as verified by multi-response optimization, thus showing that phenolics could be largely underestimated by employing an inappropriate extraction. The concentration of derivatives of apigenin, the main phenolics present, ranged from 63.5 to 80.7%, as evaluated by LC–ESI-QTOF-MS. Phenolics from the breeding line 98 exhibited the highest ability in scavenging peroxyl radicals, reducing power as well as in terms of inhibition of pancreatic lipase activity, a key enzyme regulating the absorption of triacylglycerols. In contrast, none of the samples exhibited a significant anti-diabetic potential. Despite their high concentration compared to that of phenolic acids, results of this work do not support a significant antioxidant and pancreatic lipase inhibitory effect of durum wheat flavonoids. Therefore, breeding programs and animal and/or human trials related to the effect of durum wheat flavonoids on oxidative stress and absorption of triacylglycerols are discouraged at this point.
... Brazil is the only commercial producer of guarana, with a yield of 3,726 metric tons yr −1 in 2018 (IBGE, 2019). Several studies have demonstrated guarana as a source of bioactive compounds, methylxanthines and catechins, with energetic and antioxidant properties (Marques, Ferreira, Paula, Klein, & Mello, 2019;Moustakas et al., 2015;Ruchel et al., 2017;Salomão-Oliveira, Lima, Marinho, & Carvalho, 2018;Silva, Soares-Freitas, Sampaio, Camargo, & Torres, 2019;Yonekura et al., 2016). ...
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Guarana is a typical South American plant, native to the Amazon, with subspontaneous occurrence in Maués, Amazonas‐Brazil, where it was domesticated and cultivated by the Sateré‐Mawé indigenous community. Guarana is an original Brazilian product with great economic and industrial potential owing to the energetic, antioxidant and medicinal properties of its seeds. In spite of its importance, there is still a gap in knowledge about genetic diversity and adaptations that might improve agro‐industrial uses of guarana seeds. This study was aimed at estimating phytochemical diversity, classification and typology of guarana genotypes. Agro‐industrial potential among eight genotypes was estimated based on phytochemical characters (theobromine, caffeine, catechin and epicatechin content (quantified by HPLC) and yield in three locations, in harvests between 2015 and 2016. Phytochemical divergence was assessed by the mean Euclidean distance. Grouping was performed by the Unweighted pair‐group method using arithmetic averages (UPGMA). Metabolite content varied considerably between genotypes; for example, caffeine (3.23 to 7.35%), catechin (0.20 to 3.57%) and epicatechin (0.09 to 4.22%), and dry seed yield was the character with the highest variation (0.048 to 5.13 kg.plant−1). The metabolic profile variations of the genotypes were clustered into three chemotypes: energetic and antioxidant guarana (genotypes CIR815, CIR904, CMA498); antioxidant guarana (genotypes BRS‐Maués, CMU874); and energetic guarana (genotypes CMA831, CMU952, BRS‐CG372). Genotypes CIR815, CIR904, and CMU874 have the potential to be future commercial cultivars, providing quality raw material for soft drinks, energy drinks and pharmaceutical products. This article is protected by copyright. All rights reserved
... Inhibition of alphaamylase and lipase was performed with phenolic extracts at 10 mg/ml of sample F I G U R E 3 Principal component analysis (PCA) and dendogram of different extract characteristics enzymes and phenolic compounds are mostly by van der Waals forces, hydrogen binding, hydrophobic binding, and other electrostatic forces. These interactions were previously associated to noncompetitive type inhibitions(Li, Yang, Fei, Zhang, & Wu, 2011;Martinez-Gonzalez et al., 2017;Shobana, Sreerama, & Malleshi, 2009;Wang, Dong, Zhang, Shao, & Liu, 2014;Wu et al., 2014;Yang & Kong, 2016).Wang et al. (2014) reported that grape proanthocyanidins inhibited porcine pancreatic lipase activity in a noncompetitively inhibiting manner.Procyanidins, which are the largest compounds identified in the extracts from this study, exhibit health-promoting effects, like antioxidant, antiglycemic, and antiobesity effects(de Camargo et al., 2017;de Camargo, Vidal, Canniatti-Brazaca, & Shahidi, 2014;Da Silva, Soares-Freitas, Sampaio, De Camargo, & Torres, 2019). A 25-50 mg/ day procyanidins dose "helps improve the overall aging process by protecting the skin from environmental stress" and "scientifically proven blend of synergistic natural antioxidants helping protect cells from free radical damage" (European Food Safety Authority, 2010b).Grapes, peanuts, cocoa, guarana and their processing by-products are not mentioned in the new version of the Brazilian regulation (National Health Surveillance Agency, 2019c) as approved sources of Procyanidins. ...
Agro‐industrial residues are a potential source of bioactive compounds. This research is focused on the extraction of phenolic compounds from agro‐industrial residues produced in large scale in Brazil (peanut and grape marc), as well as to evaluate their antioxidant activity and ability to inhibit glycation reactions and digestive enzymes. As glycation is the main spontaneous cause of protein damage and is involved in the progression of diseases such as diabetes and obesity. The results showed that the major polyphenolics found in the residues were catechin and procyanidin B2. All extracts significantly inhibited the in vitro formation of advanced glycation end products and digestive enzymes (α‐amylase and lipase). This is the first study that compares the effects of peanut skin and grape pomace extracts against glycation. The results corroborate the understanding that using these phenolic extracts may have beneficial effects on preventing diseases related to glycation and suggest their use as a high value‐added agro‐industrial residue. The glycation process causes oxidative stress, inflammatory responses in the human body, and is related to the progression of diabetes mellitus and obesity. This study showed that the selected industrial residues presented new results in their biological activities, mainly in relation to the high capacity to inhibit glycation and their high activity against alpha‐amylase and lipase enzymes. These residues can then be used for sustainable production of high added value products for both the food industry and the pharmaceutical industry.
... NCDs have been pointed as major health challenges of the twenty-first century. In fact, according to a recent reports, in 2016, NCDs were responsible for 71% (41 million) death worldwide and 17.9 million death were related to CVD, which was followed by cancers (9 million), chronic respiratory diseases (3.8 million), and diabetes (1.6 million death) ( Silva et al. 2019;WHO, 2018). ...
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This study aimed to evaluate the potential use of Agaricus bisporus mushroom as a natural antioxidant, fat/salt substitute and flavor enhancer in beef burger. Ten treatments were considered using a fractional factorial design (salt [0.5, 1.25 and 2.0%], fat [10, 15 and 20%] and mushroom content [0, 15 and 30%]). Treatments were characterized by instrumental and sensory measurements. The statistical design indicated that fat content had little influence on the results. The principal component analysis showed that the incorporation of mushrooms and salt modified the texture, moisture and water activity. Oxidative stability decreased as the salt content increased, at a low-fat content. Finally, the sensory profile was affected by the mushroom and salt contents, with the fat content exerting the least influence. Therefore, mushroom incorporation in beef burger may be a feasible strategy to reduce the fat content of beef burgers. Graphical abstract
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Paullinia cupana (Kunth), popularly known as guarana, is a plant species from the Amazon Region of Brazil that stands out for being one of the most promising herbal medicines of the Brazilian flora since it has relevant biological properties. However, studies are still needed to use this species as a direct approach to evaluate aspects related to behavior and oxidative stress in invertebrate model animals. In this context, we aimed to evaluate the stimulant and the antioxidant effects of P. cupana in lobster cockroach Nauphoeta cinerea. For that, cockroaches were exposed to a diet separately supplemented by the decoction of P. cupana powder decoction at increasing concentrations of 1, 25, 50 and 100 mg/g for 42 days. Behavioral and biochemical assays were performed, respectively, to assess the locomotor/exploratory performance and oxidative stress marker levels of the cockroaches. They exhibited an outstanding increase in the locomotion performance and in the cell viability content, as well as in the protein and non-protein thiol levels. Moreover, there was a decrease in lipid peroxidation levels and in free Fe2+ ion contents. Together, our results demonstrate the stimulant and the antioxidant capacity of P. cupana by acting positively in behavioral patterns and by regulating oxidative stress markers in lobster cockroach N cinerea. These findings encourage further laboratory analyzes in order to better enlighten the specific mechanisms of action attributed to guarana.
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The Brazilian Food Supplement Law recently recognized that guarana (Paullinia cupana) contains bioactive substances, hence supporting its role as a functional food ingredient. The health benefits of guarana are associated, at least in part, to its phenolic compounds. However, to the best of our knowledge, there is no literature addressing the presence of phenolic compounds in the fraction containing insoluble-bound compounds and its contribution in terms of alpha-glucosidase inhibition. The concentration of phenolic extracts released from the insoluble-bound fraction required to inhibit 50% of alpha-glucosidase (IC50) activity was 5.8-fold lower than that present in the soluble counterpart. Both fractions exhibited a mixed inhibition mode. Fourteen proanthocyanidins (dimers to tetramers) present in the insoluble-bound fraction were tentatively identified by MALDi-TOF-MS. Future studies aiming at increasing the concentration of the soluble counterpart are deemed necessary. The results presented here enhance the phenolic database of guarana and have a practical impact on the procurement of nutraceuticals and functional ingredients related to the prevention and/or management of type 2 diabetes. The Brazilian normative on food supplements has been recently revised. This study lends support to the future inclusion of guarana powder in the list of sources of proanthocyanidins for the industry of food supplements.
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Phenolic compounds constitute a large and diverse group of secondary metabolites derived from phenylalanine and tyrosine and are widely distributed throughout the plant kingdom. They could be divided into different classes such as simple phenol, phenyl acetic acid, hydroxybenzoic acid, hydroxycinnamic acid, and other phenylpropanoids as well as condensed tannins (proanthocyanidins) and hydrolysable tannins, among others, depending on their basic carbon skeleton structure. Phenolic compounds in plant-based foods have been suggested to have a number of beneficial health effects including prevention of cancer, cardiovascular disease, diabetes, immune disorders, neurogenerative disease and others. These properties are largely attributable to the antioxidant activity of the phenolic compounds as well as other mechanisms of action. Therefore, nutraceuticals of plant origin may evolve to be considered a vital aspect of dietary-disease preventive food components. Agri-food industries generate substantial quantities of phenolic rich by-products, which could serve as an attractive and commercially viable source of nutraceuticals. This contribution mainly summarizes the occurrence of phenolic compounds and some other bioactives in various Agri-food by-products, their bioavailability and health benefits.
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Modern epidemiological and interventional studies have demonstrated that various bioactivities including antioxidant, antiproliferative, immune-regulatory, hormonal-regulation abilities and neuro-/hepato-/cardioprotective effects result from consumption of a phenolic-rich diet. The health benefits of ingesting phenolics are greatly dependent on their bioaccessibility and bioavailability in the digestive tract and circulatory system. This contribution attempts to review the bioaccessibility and bioavailability of phenolic compounds by focusing on the body’s internal mechanism including digestion, absorption, transport, modification, excretion, and colonic fermentation. The bioaccessibility and bioavailability of different phenolics vary depending on the physical condition of an individual, including digestive/absorptive/metabolic/response capability and effective dose. External factors such as processing methods and interaction with various food matrices also play a vital role on the bioavailability of dietary phenolic compounds. On the other hand, some novel phenolics have been synthesized to enable them rendering new bioactivities. The key internal factors influencing the bioaccessibility and bioavailability are also reviewed in this contribution. In addition, suggestions have been made for future measurement and assessment of bioavailability, together with prospects for food/nutraceutical/pharmaceutical application of novel phenolics.
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Cardiovascular disease (CVD) is the most common non-communicable ailment which claims one-third of total global death. This contribution provides an overview of cardiovascular diseases (CVDs), hypercholesterolemia and hyperlipidemia (dyslipidemia) and their related complications as well as the current treatment options with special attention to popular functional foods and nutraceuticals. Currently, many synthetic lipid-lowering drugs are available in the market. However, they trigger several adverse effects. Thus, to overcome this problem nutraceuticals and functional foods which are considered safe, and with multifaceted lipid-lowering activity are highly recommended (adjuvant therapy) for treating dyslipidemia. This review intends to shed light on how to choose the appropriate or better nutraceutical/functional food ingredients to alleviate the risk of CVD, based on recent literature survey with the inclusion of clinical trials and meta-analysis to ensure the efficacy of nutraceuticals/ functional foods on lipid profile.
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Inflammation is a non-specific kind of biological immune response of body tissues to any type of external or internal injuries, such as pathogens, irritants and immune stress reactions. There are two types of inflammation, namely acute and chronic. Acute inflammation starts and develops rapidly, and is aroused by various factors, including injuries, infection, toxins or immune reactions. Chronic inflammation usually lasts for an extended long period of time and results from elimination failure of acute inflammation, autoimmune disorders, various pathogens and pathogenic environments. Except for the damage itself, there exists a direct and intimate connection between chronic inflammation and various clinic common diseases, such as neurodegeneration, as well as metabolic and cardiovascular ailments. Citrus peel is a by-product generated in citrus juice processing. Polymethoxyflavones (PMFs) exist abundantly and almost exclusively in citrus peels, and their biological activities have been broadly investigated in recent years. PMFs have proven to possess potential inhibitory bioactivities towards a number of functional and immune diseases including inflammation. The two most abundant PMFs exhibiting prominent bioactivities in citrus peels are nobiletin and tangeretin, ubiquitously detected in various citrus species. In this review, the beneficial health effects and the underlying molecular mechanisms of ten main citrus PMFs were illustrated against numerous inflammatory diseases, including inflammatory bowel disease (IBD), neuroinflammation and organ inflammation, among others.
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Increasing evidence suggests that food ingested polyphenols can have beneficial effects in neuronal protection acting against oxidative stress and inflammatory injury. Moreover, polyphenols have been reported to promote cognitive functions. Biotransformation of polyphenols is needed to obtain metabolites active in brain and it occurs through their processing by gut microbiota. Polyphenols metabolites could directly act as neurotransmitters crossing the blood-brain barrier or indirectly by modulating the cerebrovascular system. The microbiota-gut-brain axis is considered a neuroendocrine system that acts bidirectionally and plays an important role in stress responses. The metabolites produced by microbiota metabolism can modulate gut bacterial composition and brain biochemistry acting as neurotransmitters in the central nervous system. Gut microbiota composition can be influenced by dietary ingestion of natural bioactive molecules such as probiotics, prebiotics and polyphenol. Microbiota composition can be altered by dietary changes and gastrointestinal dysfunctions are observed in neurodegenerative diseases. In addition, several pieces of evidence support the idea that alterations in gut microbiota and enteric neuroimmune system could contribute to onset and progression of these age-related disorders. The impact of polyphenols on microbiota composition strengthens the idea that maintaining a healthy microbiome by modulating diet is essential for having a healthy brain across the lifespan. Moreover, it is emerging that they could be used as novel therapeutics to prevent brain from neurodegeneration.
The total phenolic content of date palm (Phoenix dactylifera L.) seeds (samples 1 and 2) and leaves were determined and for the first time their antioxidant activity in a food system investigated. The anti-inflammatory activity and potency of samples in the inhibition of radical-induced DNA scission and human low-density lipoprotein (LDL) cholesterol oxidation was also evaluated. The total soluble phenolic content of the date palm leaves was 106.96 mg gallic acid equivalents (GAE)/g sample and ranged from 68.73 to 82.62 mg GAE/g of date seeds. Extracts showed good radical scavenging activity in the different in vitro tests conducted in this work and were found to be effective in inhibiting the oxidation of cooked ground meat. Soluble phenolic extract from date seeds of sample 1 was most effective in inhibiting DNA strand scission by 74.15%, while soluble phenolics from palm leaves showed the highest inhibition of LDL cholesterol oxidation (87.82%). Both samples significantly inhibited mRNA level of COX-2 at concentrations as low as 5 μg/mL, with the most potent inhibitory effect being for date palm leaf extracts at 50 μg/mL. A number of phenolic compounds including proanthocyanidin dimers, catechin, epicatechin, 5-O-caffeoylshikimic acid isomers, ferulic acid, rutin and isorhamnetin hexoside, among others, were detected in date palm seeds and leaves.
Free radical imbalance is associated with several chronic diseases. However, recent controversies have put in check the validity of colorimetric methods to screen the functionality of polyphenols. Therefore, in this study two antioxidant methods, based on chemical reactions, were tested for their ability in anticipating the reduction of the activation of NF-κB using LPS-activated RAW 264.7 macrophages, selected as a biological model. Grape processing by-products from winemaking showed higher total phenolic content (TPC), antioxidant capacity towards peroxyl radical (31.1%) as well as reducing power (39.5%) than those of grape juice by-products. The same trend was observed when these samples were tested against LPS-activated RAW 264.7 macrophages by reducing the activation NF-κB. Feedstocks containing higher TPC and corresponding ORAC and FRAP results translated to higher reduction in the activation of NF-κB (36.5%). Therefore, this contribution demonstrates that colorimetric methods are still important screening tools owing their simplicity and widespread application.
Guaraná (Paullinia cupana) seeds are rich in flavan-3-ols (catechins) and reduce oxidative stress in humans. We determined the concentration and in vitro bioaccessibility of catechins in guaraná seeds from two geographical origins, and measured their Caco-2 permeability. The effect of macronutrients on catechins' bioaccessibility and Caco-2 permeability was also evaluated. Guaraná seeds from southern Bahia and Maués contained, respectively, 30.0 and 26.8 mg catechin/g, 20.2 and 20.0 mg epicatechin/g, 3.7 and 3.8 mg procyanidin B1/g, and 3.3 and 4.9 mg procyanidin B2/g. Bioaccessibility ranged between 65 and 95% for catechin monomers and 50-140% for dimers. Casein inhibited bioaccessibility of catechin dimers, while vegetable oil improved bioaccessibility of total procyanidins. Guaraná catechin monomers and dimers were able to permeate through Caco-2 cell mono-layers (P app 0.31-0.35 × 10 −6 cm/s) without effect from co-digested macronutrients. Guaraná seeds are a source of highly bioaccessible catechins, which can permeate the intestinal epithelium with negligible effect from macronutrients.
Evidence is accumulating that the gut microbiome is involved in the aetiology of obesity and obesity-related complications such as nonalcoholic fatty liver disease (NAFLD), insulin resistance and type 2 diabetes mellitus (T2DM). The gut microbiota is able to ferment indigestible carbohydrates (for example, dietary fibre), thereby yielding important metabolites such as short-chain fatty acids and succinate. Numerous animal studies and a handful of human studies suggest a beneficial role of these metabolites in the prevention and treatment of obesity and its comorbidities. Interestingly, the more distal colonic microbiota primarily ferments peptides and proteins, as availability of fermentable fibre, the major energy source for the microbiota, is limited here. This proteolytic fermentation yields mainly harmful products such as ammonia, phenols and branched-chain fatty acids, which might be detrimental for host gut and metabolic health. Therefore, a switch from proteolytic to saccharolytic fermentation could be of major interest for the prevention and/or treatment of metabolic diseases. This Review focuses on the role of products derived from microbial carbohydrate and protein fermentation in relation to obesity and obesity-associated insulin resistance, T2DM and NAFLD, and discusses the mechanisms involved.