Metabolomic approaches to explore chemodiversity in seeds of guaraná (Paullinia cupana) using UPLC-QTOF-MSE and NMR analysis.

The growing interest in health and well-being has spurred the evolution of functional foods, which provide enhanced health benefits beyond basic nutrition. Guaraná seeds (Paullinia cupana) have been widely studied and used as a functional food due to their richness in caffeine, phenolic compounds, amino acids, and other nutrients. This has established guaraná as a significant food supplement, with Brazil being the largest producer of the world. This study aims to propose a set of analytical methods to chemically evaluate fifty-six different guaraná clones, from the Guaraná Germplasm Active Bank, to accommodate the diverse requirements of the food industry. Metabolomic approaches were employed, in which a non-target metabolomic analysis via UPLC-QTOF-MSE led to the annotation of nineteen specialized metabolites. Furthermore, targeted metabolomics was also used, leading to the identification and quantification of metabolites by NMR. The extensive data generated were subjected to multivariate analysis, elucidating the similarities and differences between the evaluated guaraná seeds, particularly concerning the varying concentration levels of the metabolites. The metabolomics approach based on the combination of UPLC-QTOF-MSE, NMR and chemometric tools provided sensitivity, precision and accuracy to establish the chemical profiles of guaraná seeds. In conclusion, evaluating and determining the metabolic specificities of different guarana clones allow for their application in the development of products with different levels of specific metabolites, such as caffeine. This caters to various purposes within the food industry. Moreover, the recognized pharmacological properties of the annotated specialized metabolites affirm the use of guarana clones as an excellent nutritional source.

Guarana propagation strategies: a review.

Guarana [Paullinia cupana var. sorbilis (Mart.) Ducke] is a species of great economic and social important in Brazil, as it is the only commercial guarana producer in the world. The vegetative propagation method indicated for the culture is stem cuttings, which aims at productivity, tolerance, and uniformity of clonal cultivars, because reproduction by seeds has slow germination and high genetic variability, which in traditional varieties is an undesirable factor. Genetic factors can interfere with the rooting capacity of the crop. Studies seek alternatives that can improve this condition and enhance the production system. Use of growth regulators, microorganisms that promote plant growth, variation of substrates and fertilization, have been strategies used. Preliminary tests on the rate of stem rooting and seed germination with the use of exogenous phytohormone did not demonstrate in relation to the non-application of these inducers. The use of rhizobacteria, which presents itself as a promising activity in many cultures, has not yet been demonstrated in the culture of guarana. On the other hand, the influence of different substrates on rooting has already shown consistent results as a function of rooting rate. Fertilizing the mother plants as recommended by the production system for the crop has proven to be an efficient procedure. There are still few studies aimed at improving the spread of guarana, demonstrating that new protocols need to be explored, or that the protocols already used are reviewed from another perspective.

Metabolism of guarana (Paullinia cupana Kunth var. sorbilis) plants and fruit production subjected to glyphosate doses.

Guarana (Paullinia cupana Kunth var. sorbilis) is a typically Amazonian plant of high economic value due to the compounds found in its seed. For guarana to reach the maximum productive potential, management practices such as weed control are necessary. The use of herbicides is a viable alternative, however, its drift may lead to adverse effects on the primary and secondary plant metabolisms and cause losses in crop production. This study evaluated the differential drift effects of glyphosate doses on the physiology of guarana plants and the production of compounds of economic interest in their seeds. Glyphosate doses (57.6, 115.2, 230.4, 460.8 g ae ha-1) were applied to adult guarana plants after the flowering period. The photosynthetic functions and metabolism effects were evaluated. Herbicide treatments led to oxidative stress due to increased lipid peroxidation and increased carbohydrate and amino acid in their leaflets. Despite this, glyphosate showed no effect on fruit production or the content of secondary metabolites of commercial interest in seeds.

Alterations in Bacterial Metabolism Contribute to the Lifespan Extension Exerted by Guarana in Caenorhabditis elegans.

Guarana (Paullinia cupana) is a widely consumed nutraceutical with various health benefits supported by scientific evidence. However, its indirect health impacts through the gut microbiota have not been studied. Caenorhabditis elegans is a useful model to study both the direct and indirect effects of nutraceuticals, as the intimate association of the worm with the metabolites produced by Escherichia coli is a prototypic simplified model of our gut microbiota. We prepared an ethanoic extract of guarana seeds and assessed its antioxidant capacity in vitro, with a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, and in vivo, utilizing C. elegans. Additionally, we studied the impact of this extract on C. elegans lifespan, utilizing both viable and non-viable E. coli, and assessed the impact of guarana on E. coli folate production. The extract showed high antioxidant capacity, and it extended worm lifespan. However, the antioxidant and life-extending effects did not correlate in terms of the extract concentration. The extract-induced life extension was also less significant when utilizing dead E. coli, which may indicate that the effects of guarana on the worms work partly through modifications on E. coli metabolism. Following this observation, guarana was found to decrease E. coli folate production, revealing one possible route for its beneficial effects.

TNF-α inhibition, antioxidant effects and chemical analysis of extracts and fraction from Brazilian guaraná seed powder.

Paullinia cupana Kunth., commonly named Guaraná, is a plant from Brazil used as stimulant. The aim of this study was to evaluate the potential of extracts and tannins-rich and methylxanthines-free fraction from guaraná in the anti-inflammatory and antioxidant effect in vitro. Extract 1 obtained good yields of tannins and methylxanthines and was used to identify a type-A procyanidin trimer by LC-ESI-MS. Fraction 4 was rich in tannins and absent of methylxanthines. The extracts and fraction exhibited strong capacity for scavenging DPPH radical with IC50 between 5.88 and 42.75-µg/mL and inhibited TNF-α release by LPS-activated THP-1 cells when compared with control cells and did not present toxicity to THP-1 cells. The fraction 4, rich in tannins, was highly active, with IC50 5.88 µg/mL by DPPH method and inhibited TNF-α release in 83.50% at 90 µg/mL. These results reinforced potential anti-inflammatory of guaraná and data for new therapeutic approaches.

Identification of a cold-adapted and metal-stimulated ß-1,4-glucanase with potential use in the extraction of bioactive compounds from plants.

Cold-adapted endo-ß-1,4-glucanases hold great potential for industrial processes requiring high activity at mild temperatures such as in food processing and extraction of bioactive compounds from plants. Here, we identified and explored the specificity, mode of action, kinetic behavior, molecular structure and biotechnological application of a novel endo-ß-1,4-glucanase (XacCel8) from the phytopathogen Xanthomonas citri subsp. citri. This enzyme belongs to an uncharacterized phylogenetic branch of the glycoside hydrolase family 8 (GH8) and specifically cleaves internal ß-1,4-linkages of cellulose and mixed-linkage ß-glucans releasing short cello-oligosaccharides ranging from cellobiose to cellohexaose. XacCel8 acts in near-neutral pHs and in a broad temperature range (10-50 °C), which are distinguishing features from conventional thermophilic ß-1,4-glucanases. Interestingly, XacCel8 was greatly stimulated by cobalt ions, which conferred higher conformational stability and boosted the enzyme turnover number. The potential application of XacCel8 was demonstrated in the caffeine extraction from guarana seeds, which improved the yield by 2.5 g/kg compared to the traditional hydroethanolic method (HEM), indicating to be an effective additive in this industrial process. Therefore, XacCel8 is a metal-stimulated and cold-adapted endo-ß-1,4-glucanase that could be applied in a diverse range of biotechnological processes under mild conditions such as caffeine extraction from guarana seeds.

Caffeine and Doping-What Have We Learned since 2004.

Caffeine is a naturally occurring plant alkaloid and is found in plant constituents such as coffee and cocoa beans, tea leaves, guarana berries and the kola nut [...].

Anthelmintic A-Type Procyanidins and Further Characterization of the Phenolic Composition of a Root Extract from Paullinia pinnata.

Extracts from the roots of Paullinia pinnata L. are used in West Africa as traditional remedies for a variety of diseases including infestations with soil-transmitted helminths. Based on the results of an ethnopharmacological survey in Ghana, an aqueous acetone (70%) extract was investigated for its anthelmintic and phytochemical properties. Partitioning of the crude extract followed by several fractionation steps of the ethyl acetate phase using Sephadex® LH-20, fast centrifugal partition chromatography, RP-18-MPLC and HPLC led to isolation of six oligomeric A-type procyanidins (1 to 6). To determine the anthelmintic activity, the crude extract, fractions and isolated compounds were tested in vitro against the model organism Caenorhabditis elegans. A significantly better activity was observed for the trimeric A-type procyanidin (1) compared to a B-type trimer. However, this effect could not be generalized for the tetrameric procyanidins, for which the type of the interflavan-linkage (4→6 vs. 4→8) had the greatest impact on the bioactivity. Besides the procyanidins, three novel compounds, isofraxidin-7-O-α-l-rhamnopyranosyl-(1″→6')-ß-d-glucopyranoside (17), 4-methoxycatechol-2-O-(5''-O-vanilloyl-ß-apiofuranosyl)-(1''→2')-ß-glucopyranoside (18) and a 6-(3-methoxy-4-hydroxyphenyl)-hexane-2,4-diol-2-O-hexoside (19) were isolated together with further ten known compounds (7 to 16), mainly coumarins and coumarinolignans. Except for 3-ß-d-glucopyranosyloxy-4-methyl-2(5H)-furanone (15), none of the isolated compounds has previously been described for P. pinnata. The anthelmintic activity was attributed to the presence of procyanidins, but not to any of the other compound classes. In summary, the findings rationalize the traditional use of P. pinnata root extracts as anthelmintic remedies.

Insoluble-Bound Polyphenols Released from Guarana Powder: Inhibition of Alpha-Glucosidase and Proanthocyanidin Profile.

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.

Impact of a topical lotion, CG428, on permanent chemotherapy-induced alopecia in breast cancer survivors: a pilot randomized double-blind controlled clinical trial (VOLUME RCT).

PURPOSE: This study aimed to evaluate the impact of a topical lotion (CG428) on hair thickness and density in breast cancer survivors with permanent chemotherapy-induced alopecia (PCIA). METHODS: The study was a double-blind, randomized controlled trial which conducted from February 2016 to December 2016 at the Samsung Comprehensive Cancer Center in Seoul, South Korea. Breast cancer patients with PCIA were randomized on average of 3.5 years after chemotherapy. Topical lotion (Batch DT023) is a botanical drug under development containing a novel patented blend of 4 botanical ingredients: citrus, cocoa, guarana, and onion. Participants were asked to self-apply the study product or placebo twice per day for 6 months. Changes in hair density and thickness were assessed using a noninvasive bioengineering device, and patient-reported outcomes were evaluated at 3 and 6 months after randomization. RESULTS: A total of 35 patients were randomized to intervention (N = 18) or placebo (N = 17). Patients in the intervention group were older than those in the placebo group (52.1 vs. 41.6 years; P < 0.001). The mean hair density (SD) at baseline was 97.6 (6.4) and 126.8 (30.3) hairs/cm2 in the intervention and placebo group, respectively (P = 0.005). The corresponding values for hair thickness were 49.9 (12.7) and 48.1 (8.4) µm, respectively. After 6 months, hair density had increased by 34.7 and 24.9% compared with baseline in the intervention and control groups, respectively (P = 0.37). Corresponding values for hair thickness were 19.8 and 35.6%, respectively (P = 0.23). Similar findings were observed after age adjustment. DISCUSSION: In this pilot randomized clinical trial, we observed safety, tolerability, and a trend toward the efficacy of CG428 vs. placebo, especially regarding hair density and self-reported improvement.

Interaction between low-level laser therapy and Guarana (Paullinia cupana) extract induces antioxidant, anti-inflammatory, and anti-apoptotic effects and promotes proliferation in dermal fibroblasts.

BACKGROUND: Low-level laser therapy (LLLT) has several clinical applications; however, its benefits are not universal. Therefore, combination therapy with LLLT and extracts from the guarana (Paullinia cupana) plant may improve its effectiveness as guarana extracts exhibit anti-aging properties. OBJECTIVES: To evaluate the antioxidant, anti-inflammatory, anti-apoptotic, and proliferative effects of combined LLLT and guarana extract therapy on human dermal fibroblasts. METHODS: Human dermal fibroblasts (HFF-1) were cultured and initially exposed to several concentrations (1, 3, 5, 10, 30 µg/mL) of guarana extract. The experimental concentration of guarana extract was selected by analyzing cytokine levels, DNA oxidation, and apoptotic markers in LLLT-exposed (4 J/cm2 ) and LLLT-unexposed fibroblast cultures. After 72 hours, the cells were analyzed using spectrophotometric, fluorimetric, immunological, and gene expression (qRT-PCR) assays. Flow cytometry was used to evaluate the effect of each treatment on cell cycle. RESULTS: Fibroblasts treated with guarana (5 µg/mL) exhibited anti-inflammatory and anti-apoptotic properties been used in complementary protocols. Combined guarana and LLLT treatment significantly decreased protein carbonylation, lipoperoxidation, and DNA oxidation, downregulated the mRNA and protein expression of pro-inflammatory molecules, and upregulated IL-10 gene and protein expression. Guarana plus LLLT also decreased the levels of caspases 1, 3, and 8, increased the percentage of S-phase cells, and decreased FGF-1 and KGF-1 levels. Some of these changes were also observed after treatment with guarana or LLLT alone. CONCLUSIONS: Our results suggest that concomitant treatment with guarana and LLLT may promote fibroblast biostimulation and thus is clinically relevant.

Chemical analysis of the semipurified extract of Paullinia cupana and evaluation of in vitro inhibitory effects against Helicobacter pylori.

Paullinia cupana Kunth, commonly known as guarana, is a native Brazilian plant species from the Amazon area that presents various biological effects, including antimicrobial action. The aim of this study was to chemically analyse the semipurified aqueous extract (AqF) of the plant and to evaluate the activity of crude (CE), ethyl-acetate (EAF), and AqF extracts against Helicobacter pylori. The chemical profile of AqF was determined based on solid analysis 13C-NMR, direct infusion mass spectrometry (ESI-MS), and MALDI-TOF. The 13C-NMR spectrum showed characteristics of flavan-3-ol and oligomeric proanthocyanidins. ESI-MS revealed the presence of procyanidin, caffeic acid and its derivatives. MALDI-TOF analysis detected procyanidins of up to 6 units and profisetinidins of up to 5 units. Whereas CE and EAF showed inhibitory activity against H. pylori, CE, EAF, and AqF presented not high inhibitory activity against urease. The results demonstrate the potential of P. cupana to control and prevent H. pylori infection.

Safety of Guarana Seed as a Dietary Ingredient: A Review.

The seeds of the guarana plant (Paullinia cupana Kunth, family Sapindaceae) are well-known to many cultures as a stimulant, aphrodisiac, and astringent. Its rhizome was traditionally boiled into a tea by Amazonian cultures. Today, guarana seeds are ground to a fine powder and sold as powder, tablets, and capsules. This review focuses on the traditional uses, phytochemistry, and biological activities of the guarana seed to evaluate its safety as a dietary ingredient. A comprehensive review of published literature was conducted to identify articles that focused on the phytochemistry, pharmacology, and safety of guarana. On the basis of this review, guarana is not currently known to be associated causally with any serious health risks when consumed properly. Overall, guarana is generally recognized as safe as a dietary ingredient marketed for its flavor and caffeine content. If guidelines for caffeine intake are respected, guarana consumption is not likely to be associated with any serious health risks.

Production and characterization of solid lipid microparticles loaded with guaraná (Paullinia cupana) seed extract.

Guaraná is a native fruit of the Amazon rainforest, which presents high levels of phenolic compounds. However, these bioactive compounds may be unstable in food processing and gastrointestinal conditions. Thus, this work aimed to characterize guaraná seed extract (GSE) followed by microencapsulation using a spray-chilling method and with vegetable fat as carrier, as well as to evaluate the particles. Phenolic-rich GSE was produced using 50% (w/w) hydroalcoholic solution and dehydrated by spray drying and lyophilization. Powdered GSE was characterized in relation to its inhibitory activity on digestive enzymes. Solid lipid microparticles (SLM) were evaluated for the retention of bioactive compounds and the release profile of phenolic compounds in simulated gastrointestinal conditions. Powdered GSE showed anti-obesity potential due to the high inhibitory activity of lipase. Regarding the retention of phenolic compounds, at least 75% were detected after 90 days at 25 °C in SLM. Moreover, SLM loaded with 7.5% GSE released approximately 99% of phenolic compounds in simulated gastrointestinal conditions. These results show the efficiency of spray chilling for protection and release of phenolic compounds from GSE, allowing future application in food.

Guarana supplementation attenuated obesity, insulin resistance, and adipokines dysregulation induced by a standardized human Western diet via brown adipose tissue activation.

Obesity is a metabolic disorder associated with adverse health consequences that has increased worldwide at an epidemic rate. This has encouraged many people to utilize nonprescription herbal supplements for weight loss without knowledge of their safety or efficacy. However, mounting evidence has shown that some herbal supplements used for weight loss are associated with adverse effects. Guarana seed powder is a popular nonprescription dietary herb supplement marketed for weight loss, but no study has demonstrated its efficacy or safety when administered alone. Wistar rats were fed four different diets (low-fat diet and Western diet with or without guarana supplementation) for 18 weeks. Metabolic parameters, gut microbiota changes, and toxicity were then characterized. Guarana seed powder supplementation prevented weight gain, insulin resistance, and adipokine dysregulation induced by Western diet compared with the control diet. Guarana induced brown adipose tissue expansion, mitochondrial biogenesis, uncoupling protein-1 overexpression, AMPK activation, and minor changes in gut microbiota. Molecular docking suggested a direct activation of AMPK by four guarana compounds tested here. We propose that brown adipose tissue activation is one of the action mechanisms involved in guarana supplementation-induced weight loss and that direct AMPK activation may underlie this mechanism. In summary, guarana is an attractive potential therapeutic agent to treat obesity.

Aqueous and methanol extracts of Paullinia pinnata L. (Sapindaceae) improve inflammation, pain and histological features in CFA-induced mono-arthritis: Evidence from in vivo and in vitro studies.

ETHNOPHARMACOLOGICAL RELEVANCE: Paullinia pinnata L. (Sapindaceae) is an African woody vine, traditionally used for the treatment of itch and pain-related conditions such as rheumatoid arthritis. AIM: This work evaluates, in vitro and in vivo, the anti-inflammatory and analgesic effects of aqueous (AEPP) and methanol (MEPP) extracts from Paullinia pinnata leaves. METHODS: AEPP and MEPP (100, 200 and 300 mg/kg/day) were administered orally in monoarthritic rats induced by a unilateral injection of 50 µl of Complete Freund's Adjuvant (CFA) in the ankle joint. During the 14 days of treatment, pain and inflammation were evaluated alternatively in both ankle and paw of the CFA-injected leg. Malondialdehyde (MDA) and glutathione (GSH) levels were assessed in serum and spinal cord. Histology of soft tissue of the ankle was also analyzed. For in vitro studies, AEPP and MEPP (10, 30 and 100 µg/ml) were evaluated against nitric oxide (NO) production by macrophages that were either non-stimulated or stimulated with LPS, 8-Br-AMPc and the mixture of both substances after 8 h exposure. These extracts were also evaluated on TNF-α and IL-1ß production in cells stimulated with LPS for 8 h. Finally, the ability of the extracts to bind to neuroactive receptors was evaluated in vitro using competitive binding assays with >45 molecular targets. RESULTS: AEPP and MEPP significantly reduced by 20-98% (p < 0.001) the inflammation and pain sensation in both the ankle and paw. AEPP significantly increased glutathione levels (p < 0.05) in serum. Both extracts reduced MDA production in serum and spinal cord (p < 0.001), and significantly improved tissue reorganization in treated arthritic rats. P. pinnata extracts did not affect NO production in non-stimulated macrophages but significantly reduced it by 47-88% in stimulated macrophages. AEPP and MEPP also significantly inhibited TNF-α (35-68%) and IL-1ß (31-36%) production in LPS stimulated macrophages. No cytotoxic effect of plant extracts was observed. MEPP showed concentration-dependent affinity for Sigma 2 receptors with an IC50 of 50 µg/ml. CONCLUSION: These results demonstrate the analgesic and anti-inflammatory effects of P. pinnata extracts on monoarthritis and further support its traditional use for pain and inflammation. These activities are at least partly due to the ability of these extracts to inhibit the production of NO, TNF-α, IL-1ß and to likely modulate Sigma 2 receptors.

Effects of hydroalcoholic and enzyme-assisted extraction processes on the recovery of catechins and methylxanthines from crude and waste seeds of guarana (Paullinia cupana).

Catechins and methylxanthines are natural molecules in guarana (Paullinia cupana) that are associated with antioxidant and stimulatory effects in the human body. There are few natural sources of these antioxidants. The most popular molecule used in foods and beverages is caffeine, which, most of the time, is derived from synthetic sources. In this work, cold hydroalcoholic (CHM), hot hydroalcoholic (HHM), and aqueous enzymatic maceration (AEM) were applied to crude (CG) and waste guarana seeds (WG) to process these materials into natural added-value products with enhanced levels of catechin, epicatechin, epicatechin gallate, caffeine, theobromine and theophylline. The highest level of catechins and methylxanthines was extracted with HHM. Nevertheless, AEM enhanced the global yield in the extract, probably due to the solubilization of other substances. The maceration procedures applied to guarana contributed to the valorization of this plant crop by providing antioxidant sources with clear applications in food and nonfood industries.

Effects of Carbohydrate, Caffeine, and Guarana on Cognitive Performance, Perceived Exertion, and Shooting Performance in High-Level Athletes.

Purpose: To investigate the effect of ingesting carbohydrate (CHO), caffeine  (CAF), and a guarana complex (GUAc) during a running exercise on cognitive performance, rating of perceived exertion (RPE), and shooting performance in high-level modern pentathlon athletes. Methods: A total of 10 athletes completed 4 counterbalanced sessions within a 2-wk period, corresponding to ingestions of CHO (30 g), GUAc (300 mg), CAF (200 mg), or placebo. The exercise involved a 40-min run on a treadmill at a steady speed, previously determined as a "somewhat hard" exercise (RPE 13). Shooting and cognitive performance (Simon task) were assessed in 3 phases: before exercise and ingestion, before exercise and after half ingestion, and after exercise and full ingestion. Drinks were consumed 40 min (250 mL) and 5 min (125 mL) prior to exercise and after 20 min of running (125 mL). RPE was assessed at 10-min intervals during exercise. Results: There was an interaction between drink and exercise on mean reaction time (P = .01, ηp2=.41 ) and a drink effect on RPE (P = .01, ηp2=.15 ). CHO, CAF, and GUAc enhanced the speed of information processing after exercise (P = .003, P = .004, and P = .04, respectively), but only CAF and GUAc decreased RPE (P = .002 and P = .02, respectively). Conclusion: The results highlight a beneficial effect of nutritional supplements on information processing and RPE. This finding is particularly interesting as decision-making processes are crucial in the performance of many sports.

Microwave-assisted digestion using diluted HNO3 and H2O2 for macro and microelements determination in guarana samples by ICP OES.

A microwave-assisted digestion procedure using diluted HNO3 and H2O2 was developed for multi-element determination in guarana samples by ICP OES. Optimization step was performed employing a mixture design with pseudocomponents using HNO3, H2O2 and H2O. The analytical signal of each element, residual acidity and residual carbon content were optimized simultaneously using the desirability function. The best condition for digestion of a 250 mg sample mass resulted from a mixture constituted by 1.0 mL of HNO3, 3.0 mL of H2O2 and 6.0 mL of H2O. This condition allowed final digests with residual acidity and residual carbon content of 0.4 mol L-1 and 6.5%, respectively. The method was validated and applied for the determination of K, Ca, Mg, S, P, Cu, Fe, Mn and Zn in 72 guarana seed samples from Bahia state. This work presents unpublished results about the mineral composition of guarana seed samples produced in Bahia state, Brazil.

Guarana seed extracts as a useful strategy to extend the shelf life of pork patties: UHPLC-ESI/QTOF phenolic profile and impact on microbial inactivation, lipid and protein oxidation and antioxidant capacity.

The antioxidant and antimicrobial effects of guarana seed extracts (GSE) added to pork patties were evaluated for 18 days storage at 2 ±â€¯1 °C. Five treatments were prepared: i) without natural antioxidant [control (negative control)], ii) with BHT at 200 mg/kg (positive control), and iii) with three different concentrations: 250  mg/kg (guarana seed low dose-GSL), 500  mg/kg (guarana seed medium dose-GSM) and 1000  mg/kg (guarana seed high dose-GSH) of guarana extracts, respectively. The pH, instrumental colour (CIE L*, a*, b*), total viable counts (TVC), Pseudomonas spp. counts and lactic acid bacteria (LAB) counts, 2-thiobarbituric acid reactive substances (TBARS) and carbonyl content were determined after 0, 7, 11, 15 and 18 days of storage period. The in vitro antioxidant activity together with the phenolic profile of GSE was also studied. Microbial analysis showed that GSE had no antimicrobial activity on pork patties. The untargeted UHPLC-ESI-QTOF approach confirmed the wide phenolic composition of GSE able to explain the antioxidant power (28.2 g/kg of phenolic equivalents). Low doses (GSL) of GSE were able to preserve the values of colour parameters, obtaining higher L*, a* and b* values during storage, which is reflected in the lowest colour differences during storage (ΔE*0-18 = 4.56). TBARS and carbonyls values in GSE added samples were lower than control and BHT ones. GSL and GSM provided better results than the synthetic antioxidant (0.08 and 0.07 vs 0.18 mg MDA/kg; 2.47 and 3.13 vs 3.23 nmol/mg, for GSL and GSM vs BHT, respectively). These findings show that GSE are very effective against colour deterioration, lipid and protein oxidation in pork patties and possessing the potential to be used as natural antioxidants.