Antioxidant and tyrosinase inhibitory activity of Rosa roxburghii fruit and identification of main bioactive phytochemicals by UPLC‐Triple‐TOF/MS

The content of bioactive phytochemicals, antioxidant activity and tyrosinase inhibitory activity of the hydroalcoholic extracts of Rosa roxburghii were determined. Yellow fruits of cultivated R. roxburghii showed the highest phenolic content (154.81 mg gallic acid g^?1), and the green fruits of wild R. roxburghii showed higher content of flavonoid and triterpenoid. Rosa roxburghii fruits from different cultivars and maturity stages all demonstrated as good antioxidant agents and tyrosinase inhibitors, with IC50 value about twice of the positive standard in the DPPH assay and triple of the standard in the tyrosinase inhibitory activity assay. Nineteen compounds, mainly ellagic acids and its derivatives, flavonoids and their glycosides were identified by UPLC‐Triple‐TOF/MS analysis. As the first study of bioactive phytochemicals of R. roxburghii by UPLC‐MS, the present research may provide valuable information for fulfilling the potential of R. roxburghii in the functional food area.     

Comparison of Polyphenol Profile and Inhibitory Activities Against Oxidation and α‐Glucosidase in Mulberry (Genus Morus) Cultivars from China

Mulberry (genus Morus) is a significant source of polyphenols, which can promote positive effects on human health. China has various mulberry cultivars, however, many Chinese mulberry cultivars have been only minimally studied. To solve this lack of research, 8 mulberry cultivars (Da10, Tang10, Yueshen74, Yuefenshen, Longsang, Ningxia1hao, Taiwanguosang, and Baiyuwang) from 4 regions of China were assessed to determine their polyphenol profiles using HPLC‐MS/MS and then tested for their antioxidant and anti‐α‐glucosidase activities in vitro. A total of 18 nonanthocyanins and 4 anthocyanins were quantified in mulberry cultivars; among these polyphenols, chlorogenic acid, quercetin 3‐O‐rutinoside, and cyanidin 3‐O‐glucoside were confirmed as the major phenolic acid, flavonol derivative, and anthocyanin, respectively. Two types of stilbene compounds, piceid, and piceatannol, were detected for the 1st time in all mulberry cultivars. Moreover, the methanolic extracts of different mulberry cultivars showed disparate antioxidant and α‐glucosidase inhibitory activities, and this discrepancy was mainly attributed to varying the anthocyanin content. Based on our results, Taiwanguosang is proposed to be a good candidate suitable for further process due to its high level of anthocyanins.     

Synthesis of Quercetin‐3‐O‐Glucoside from Rutin by Penicillium decumbens Naringinase

Enzymatic bioconversion of rutin to quercetin‐3‐O‐glucoside (Q‐3‐G) by Penicillium decumbens naringinase was increased with reaction pH increased approximately to pH 6.0. It resulted in greater than 92% production of Q‐3‐G due to the removal of the terminal rhamnose at the controlled pH 6.0. The enzymatic bioconversion of rutin to Q‐3‐G was repetitively performed, yielding 84% after 5 batches with little quercetin formation. Interestingly, the water solubility of Q‐3‐G was enhanced 69‐ and 328‐fold over those of rutin and quercetin, which may make Q‐3‐G more bioavailable in food. Q‐3‐G was approximately 6‐ and 1.4‐fold more potent than rutin as an inhibitor of human intestinal maltase and human DL‐3‐hydroxy‐3‐methylglutalyl coenzyme A reductase. Q‐3‐G was less potent (16‐ and 1.3‐fold, respectively) than quercetin as an inhibitor of these enzymes. However, the results suggest that Q‐3‐G may be confirmed more effective and bioavailable food component than rutin and even quercetin because of its enhanced solubility and inhibitory properties. Practical Application : Bioconverted intermediate, quercetin‐3‐O‐glucoside (Q‐3‐G), was found and confirmed to be largely more soluble than rutin and quercetin in water solution, which might make it more bioavailable as food ingredient. In addition, Q‐3‐G inhibited mildly the intestinal maltase, which might act as antidiabetic substance by modulating the adsorption of glucose in the intestine.     

Anti-diabetic activities of phenolic compounds in muscadine against alpha-glucosidase and pancreatic lipase

Inhibitory mode and anti-diabetic activities of the Carols muscadine extracts on the α-glucosidase and pancreatic lipase were investigated. The IC₅₀ values of the muscadine and its seed methanolic extracts against the α-glucosidase were 1.92 and 1.53 mg/mL, and those against the lipase were 34.41 and 8.63 mg/mL, respectively, which indicated the muscadine possessed the strong anti-diabetes activity. Particularly, the ethyl acetate (EtOAc) extract fractions exhibited the highest inhibitory activities against both enzymes. Since most of the phenolic compounds existed in the EtOAc fractions, it is suggested that phenolic compounds may be the main source against the α-glucosidase and pancreatic lipase. Twelve individual phenolics were identified by HPLC-MS. Ellagic acid and quercetin exhibited much stronger anti-diabetic activities among the selected phenolic standards. Besides, the extracts and the phenolic standards obeyed the competitive mode in their enzymatic inhibitions.     

Polyphenols Extracted from Black Tea (Camellia sinensis) Residue by Hot‐Compressed Water and Their Inhibitory Effect on Pancreatic Lipase in vitro

Abstract: Polyphenols, retained in black tea wastes following the commercial production of tea beverages, represent an underutilized resource. The purpose of this study was to investigate the potential use of hot‐compressed water (HCW) for the extraction of pancreatic lipase‐inhibiting polyphenols from black tea residues. Black tea residues were treated with HCW at 10 °C intervals, from 100 to 200 °C. The resulting extracts were analyzed using high‐performance liquid chromatography‐mass spectrometry and assayed to determine their inhibitory effect on pancreatic lipase activity in vitro. Four theaflavins (TF), 5 catechins, 2 quercetin glycosides, quinic acid, gallic acid, and caffeine were identified. The total polyphenol content of extracts increased with increasing temperature but lipase inhibitors (TF, theaflavin 3‐O‐gallate, theaflavin 3′‐O‐gallate, theaflavin 3,3′‐O‐gallate, epigallocatechin gallate, and epicatechin gallate) decreased over 150 °C. All extracts inhibited pancreatic lipase but extracts obtained at 100 to 140 °C showed the greatest lipase inhibition (IC₅₀s of 0.9 to 1.3 μg/mL), consistent with the optimal extraction of TFs and catechins except catechin by HCW between 130 and 150 °C. HCW can be used to extract pancreatic lipase‐inhibiting polyphenols from black tea waste. These extracts have potential uses, as dietary supplements and medications, for the prevention and treatment of obesity. Practical Application: Active forms of lipase inhibitors can be recovered from black tea residues. They could be used as dietary supplements or medications.     

Phenolic Compounds and Antioxidant Capacities of 10 Common Edible Flowers from China

The free and bound phenolic compounds in 10 common Chinese edible flowers were investigated using reversed phase high‐performance liquid chromatography. Their antioxidant capacities were evaluated using 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical‐scavenging activity, 2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) radical‐scavenging activity, oxygen radical absorption capacity (ORAC), ferric reducing antioxidant power (FRAP), and cellular antioxidant activity (CAA). Free factions were more prominent in phenolic content and antioxidant capacity than bound fractions. Paeonia suffruticosa and Flos lonicerae showed the highest total phenolic content (TPC) 235.5 mg chlorogenic acid equivalents/g of dry weight and total flavonoid content 89.38 mg rutin equivalents/g of dry weight. The major phenolic compounds identified were gallic acid, chlorogenic acid, and rutin. P. suffruticosa had the highest antioxidant capacity in the DPPH, ABTS, and ORAC assays, which were 1028, 2065, 990 μmol Trolox equivalents/g of dry weight, respectively, whereas Rosa chinensis had the highest FRAP value (2645 μmol Fe²⁺ equivalents /g of dry weight). The P. suffruticosa soluble phenolics had the highest CAA, with the median effective dose (EC₅₀) 26.7 and 153 μmol quercetin equivalents/100 g of dry weight in the phosphate buffered saline (PBS) and no PBS wash protocol, respectively. TPC was strongly correlated with antioxidant capacity (R = 0.8443 to 0.9978, P < 0.01), which indicated that phenolics were the major contributors to the antioxidant activity of the selected edible flowers.     

Composition of native Australian herbs polyphenolic-rich fractions and in vitro inhibitory activities against key enzymes relevant to metabolic syndrome

Polyphenolic-rich fractions obtained from three native Australian herbs: Tasmannia pepper leaf, anise myrtle and lemon myrtle were characterised with regards to their composition, antioxidant capacities and inhibitory activities against α-glucosidase, pancreatic lipase and angiotensin I-converting enzyme, using in vitro models. Ellagic acid and derivatives were the dominant compounds of anise myrtle and lemon myrtle fractions, accompanied by flavonoids (catechin, myricetin, hesperetin, and quercetin). Tasmannia pepper leaf fraction comprised chlorogenic acid and quercetin derivatives, exhibited the highest oxygen radical absorbance capacity and effectively inhibited α-glucosidase (IC₅₀: 0.83 mg/ml) and pancreatic lipase (IC₅₀: 0.60 mg/ml). Anise myrtle and lemon myrtle fractions had pronounced α-glucosidase-inhibitory activities (IC₅₀: 0.30 and 0.13 mg/ml, respectively) and were less effective against lipase. Enzyme-inhibitory activities showed various levels of correlation with the levels of total phenolics and antioxidant capacities, indicating a specificity of individual phenolic compounds present in the isolated fractions to complex with proteins.     

Pomological features, nutritional quality, polyphenol content analysis, and antioxidant properties of domesticated and 3 wild ecotype forms of raspberries (Rubus idaeus L.)

Abstract: The raspberry (Rubus idaeus L.) is an economically important berry crop that contains many phenolic compounds with potential health benefits. In this study, important pomological features, including nutrient content and antioxidant properties, of a domesticated and 3 wild (Yayla, Yavuzlar, and Yedigöl) raspberry fruits were evaluated. Also, the amount of total phenolics and flavonoids in lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits were calculated as gallic acid equivalents (GAEs) and quercetin equivalents (QE). The highest phenolic compounds were found in wild Yayla ecotype (26.66 ± 3.26 GAE/mg extract). Whilst, the highest flavonoids were determined in wild Yedigöl ecotype (6.09 ± 1.21 QA/mg extract). The antioxidant activity of lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits were investigated as trolox equivalents using different in vitro assays including DPPH^?, ABTS^?+, DMPD^?+, and O^??₂ radical scavenging activities, H₂O₂ scavenging activity, ferric (Fe³⁺) and cupric ions (Cu²⁺) reducing abilities, ferrous ions (Fe²⁺) chelating activity. In addition, quantitative amounts of caffeic acid, ferulic acid, syringic acid, ellagic acid, quercetin, α‐tocopherol, pyrogallol, p‐hydroxybenzoic acid, vanillin, p‐coumaric acid, gallic acid, and ascorbic acid in lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits were detected by high‐performance liquid chromatography and tandem mass spectrometry (LC‐MS‐MS). The results clearly show that p‐coumaric acid is the main phenolic acid responsible for the antioxidant and radical scavenging activity of lyophilized aqueous extracts of domesticated and wild ecotypes of raspberry fruits.     

Salt effect on phenolics and antioxidant activities of Tunisian and Canadian sweet marjoram (Origanum majorana L.) shoots

BACKGROUND: Two varieties of Origanum majorana (Canadian and Tunisian) were evaluated for their phenolic, flavonoid and tannin contents, individual phenolic compounds and antioxidant activities under NaCl constraint. RESULTS: The results showed a significant variability in phenolic composition and antioxidant behavior between the two varieties under salt stress. The phenolic composition of methanolic extracts was determined by reversed‐phase high‐performance liquid chromatography. Amentoflavone was the predominant flavonoid compound; in addition, trans‐2‐hydrocinnamic acid became the major phenolic acid with salt treatment of the Tunisian variety. In the control, Canadian variety extract was characterized by high levels of gallic acid and amentoflavone. However, under 75 mmol L^?1 NaCl, gallic acid content doubled, whereas amentoflavone content was maintained in the Canadian variety. Stimulation of phenolic acid biosynthesis was observed in these two varieties under salt treatment despite the fact that shoots of the Tunisian variety showed higher antioxidant activities compared to those from the Canadian variety. Tunisian O. majorana might have developed tolerance to salinity and avoided tissue damage by activating enzymes involved in the galactosylation of quercetin into quercetin‐3‐galactoside and quercetin‐3‐rhamnoside. CONCLUSION: Our results confirmed the tolerance of Tunisian O. majorana plants. Copyright © 2012 Society of Chemical Industry     

Phenolic profile and changes in the antioxidant activity of crabapple (Malus domestica cv Royalty) fruit during maturation on the tree

The fruits of crabapple (Malus domestica cv Royalty) harvested at six times during fruit maturation on the tree (60, 80, 100, 120, 140 and 160 day after full bloom, DAFB) were evaluated for their antioxidant potentials by various assays such as DPPH, ABTS, superoxide anion, hydroxyl radical and ferric reducing power. Total phenolic and flavonoid were analysed and characterised using HPLC‐DAD‐MS/MS. Results showed that the Royalty fruits harvested on 60 DAFB had the strongest scavenging activity against DPPH, ABTS and radicals ( = 0.37 mg mL^?1,  = 0.19 mg mL^?1 and  = 4906.63 U L^?1) and ferric reducing power (FRAP = 2.85 mol Fe²⁺ per kg dw), which highly correlated with its high amount of total phenolics of 130.17 mg gallic acid equivalents (GAE) per gram dry weight and total flavonoid of 866.15 mg rutin equivalents (RE) per gram dry weight. Eight phenolic compounds were identified in the Royalty extract of 60 DAFB as caffeic acid, eriodictyol rhamnoside, phloretin hexoside I, coumaroyl guinic acid, quercetin hexoside, phloretin hexoside II, quercetin pentoside and quercetin rhamnoside. These findings suggest that Royalty could be potentially used as a promising source of natural antioxidants in the development of functional foods.     

Screening grape seeds recovered from winemaking by‐products as sources of reducing agents and mammalian α‐glucosidase and α‐amylase inhibitors

Grape seeds collected from vinification of various grape varieties were extracted by supercritical CO₂ for oil recovery. The defatted residues thus obtained were considered as a re‐utilisable co‐product and assessed for phenolic content, reducing capacity and inhibitory activities against mammalian α‐amylase and α‐glucosidase enzymes. Supercritical CO₂ treatment led to higher recovery of anthocyanins. Reducing capacity of phenolic extracts reached up to ~2200 mmolFe(II) kg^?1, much higher than that of various natural phenolic sources. The anthocyanin‐rich extracts showed the highest inhibitory effectiveness towards α‐glucosidase (I₅₀ value equal to ~40 μg gallic acid equivalents (GAE)/mL ~ half than acarbose). Inhibitory effectiveness towards α‐amylase activity was similar among grape varieties, with I₅₀ values comparable to that of acarbose and correlated with proanthocyanidin contents. These results could pave the way for an efficient processing of grapes, including cascade processes, namely: winemaking, oil extraction from recovered grape seeds and phenolic extraction from defatted grape seeds as potential cost‐effective nutraceuticals.     

The Phenolic Compounds,Metabolites, and Antioxidant Activity of Propolis Extracted by Ultrasound‐Assisted Method

The influences of ultrasound‐assisted, pharmacopeia, and supercritical fluid extraction methods on bioactive compounds and biological activities of propolis were evaluated. Results showed that propolis extracted by ultrasound‐assisted method contained more phenolic compounds, and showed the highest total phenolic content (245.84 ± 6.41 mg GAE/g DW), total flavonoids content (198.82 ± 5.74 mg RE/g DW), and stronger in vitro antioxidant activity (DPPH·: 1.03 ± 0.04 mmol Trolox/g DW, ABTS+·: 2.19 ± 0.05 mmol Trolox/g DW, and FRAP: 1.48 ± 0.12 mmol FeSO₄/g DW) than those of pharmacopoeia and supercritical fluid methods. A total of 36 phenolic compounds were identified in propolis. Among them, quercetin, quercetin‐3‐methyl‐ether, kaempferol, isorhamnetin, luteolin‐methyl‐ether, and quercetin‐7‐methyl‐ether could only be found in ultrasound‐assisted and pharmacopoeia methods. Moreover, the phenolic compounds had the similar metabolic pathways in rats and were mainly metabolized by sulfation and glucuronidation pathways. Additionally, ultrasonic‐treated propolis have good in vivo antioxidant activity and could repair D‐galactose‐induced oxidative damage in rats. Therefore, ultrasound‐assisted method could replace pharmacopeia method to be considered as bioactive compounds extraction from propolis, taking into consideration of yield, short extraction time, and high antioxidant activity.     

Extraction,identification and enzymatic synthesis of acylated derivatives of anthocyanins from jaboticaba (Myrciaria cauliflora) fruits

Polyphenols were extracted from the skin of jabuticaba fruits (Myrciaria cauliflora). Their total concentration and in vitro antioxidant activity were analysed by the DPPH and ABTS methods. The corresponding results (dry basis) were 1290 mg gallic acid equivalent (GAE)?(100 g)^?1, 98% of DPPH radical inhibition and 120 μm TEAC?g^?1 (ABTS method). All these values are at least as higher as average values reported in the literature for other fruits. A more specific analysis of the fractions of phenolic compounds was also performed by HPLC‐MS. Ellagic acid, quercetin, rutin, delphinidin‐3‐glucoside and cyanidin‐3‐glucoside were the main compounds detected; the latter two were the most abundant. The crude extract was subjected to enzymatic acylation assays in order to synthesise new esters with new potential techno‐functionalities. Palmitic acid was used as acyl donor and lipase B of Candida antactica (CALB) as biocatalyst. HPLC‐MS evidenced the formation of palmitic monoesters in connection with the delphinidin‐3‐glucoside and cyanidin‐3‐glucoside fractions.     

Composition and inhibitory activities towards digestive enzymes of polyphenolic-rich fractions of Davidson's plum and quandong

Davidson's plum (DP; Davidsonia pruriens, F. Muell, Cunoniaceae) and quandong (QD; Santalum acuminatum, A.D.C., Santalaceae) are two leading commercially grown native Australian fruits used in a variety of food products such as jam, chutney, sauces, wine or herbal teas. Within this study their inhibitory activities towards key enzymes relevant to metabolic syndrome: α-glucosidase, pancreatic lipase and angiotensin I-converting enzyme were evaluated and compared to these of reference samples: rabbit eye (REB, Vaccinium ashei J.M. Reade) and southern highbush (SHB, Vaccinium darrowii × Vaccinium corymbosum) blueberries. Polyphenolic-rich fraction obtained from DP comprised ellagic acid and ellagitannins accompanied by flavonoids: myricetin, quercetin, rutin, and anthocyanins. This fraction contained the highest level of total phenolics and exhibited superior antioxidant capacity (Ferric Reducing Antioxidant Power, FRAP and Oxygen Radical Absorbance Capacity, ORAC) to polyphenolic-rich fractions of QD, REB and SHB. DP closely followed REB and SHB in their inhibitory activities against isolated α-glucosidase (IC₅₀ of 0.13; 0.097 and 0.091, respectively) and was the most efficient inhibitor of angiotensin converting-enzyme (ACE; 91.2% inhibition at extract concentration of 1 mg/mL). Polyphenolic-rich fraction of QD comprising hydroxycinnamic acids, quercetin and cyanidin 3-glucoside was the most effective inhibitor of pancreatic lipase (IC₅₀: 0.60 mg/mL).     

Chemical,antioxidant and antibacterial study of Brazilian fruits

In this study, the antioxidant capability, total phenolic content and antimicrobial activity of ethanolic extracts of seven fruits from the Brazilian Atlantic Forest were evaluated. The conditions for the extraction of crude phenolics from the fruits were determined using an experimental factorial design. Total phenolic content, 1,1‐diphenyl‐2‐picrylhydrazyl radical (DPPH^?) scavenging activity and β‐carotene‐linoleic acid couple oxidation assays were used to evaluate the antioxidant properties of the extracts. In addition, antimicrobial activity was screened using two Gram‐negative bacteria (Escherichia coli and Klebsiella pneumoniae) and one Gram‐positive bacterium (Staphylococcus aureus). All native fruits assayed in this study have high potential as natural antioxidant sources. Among the seven fruits evaluated, Jabuticaba and Uvaia had the highest antioxidant activity in the DPPH^? and of β‐carotene‐linoleic acid coupled oxidation assays. In the biological assay, K. pneumoniae was the most sensitive microorganism to the fruit extracts, and the Jabuticaba extract had a slight inhibitory effect against this Gram‐positive bacterium.     

Chemical composition,antioxidant activity and anti‐lipase activity of Origanum vulgare and Lippia turbinata essential oils

This study reported the chemical composition, phenolic content, antioxidant and anti‐lipase activity of oregano and Lippia essential oils. The major compounds found in oregano essential oil were γ‐terpinene (32.10%), α‐terpinene (15.10%), p‐cymene (8.00%) and thymol (8.00%). In Lippia essential oil, α‐limonene (76.80%) and 1,8‐cineole (4.95%) represented the major compounds. Oregano essential oil had higher phenolic content (12.47 mg gallic acid mL^?1) and DPPH scavenging activity (IC₅₀ 0.357 μg mL^?1) than Lippia essential oil (7.94 mg gallic acid mL^?1 and IC₅₀ 0.400 μg mL^?1, respectively). Both essential oils had similar antioxidant indexes (about 1.2) determined by Rancimat. Moreover, oregano essential oil had also higher anti‐lipase activity (IC₅₀ 5.09 and 7.26 μg mL^?1). Higher phenolic content in the essential oils was related with higher scavenging and anti‐lipase activities. Oregano and Lippia essential oils could be used as natural antioxidants on food products.     

Enhancement of the antioxidant and starch hydrolase inhibitory activities of king coconut water (Cocos nucifera var. aurantiaca) by fermentation with kombucha ‘tea fungus’

Enhancement of antioxidant and starch hydrolase inhibitory properties of king coconut water when subjected to fermentation with the ‘tea fungus’ was evaluated. pH, colour, viscosity, ethanol content, antioxidant activity, total phenolic content, ferulic and p‐coumaric acid contents and starch hydrolase inhibitory activities were analysed for 7 days in fermented and unfermented king coconut water samples. The fermented sample had a statistically significant decrease (P < 0.05) in pH. Colour values indicated the fermented beverage to increase in ‘yellowness’ over time. A statistically significant increase in the total phenolic content and the antioxidant activity (P < 0.05) was observed from day 1 onwards in the fermented sample. The starch hydrolase inhibitory activities in the fermented beverage had statistically significantly increased (P < 0.05) by day 7. Overall, the study highlights an enhancement of the antioxidant and starch hydrolase inhibitory properties of king coconut water as a result of the kombucha‐based fermentation.     

Absorption and twenty‐four‐hour metabolism time‐course of quercetin‐3‐O‐glucoside in rats,in vivo

Rats were meal‐fed a semi‐synthetic diet, with or without quercetin 3‐O‐glucoside (Q3G; 100 mg per meal) and groups of three were killed either fasting, or at 2, 5 and 24 post‐feeding. Flavonoids and their metabolites in the diet, stomach contents, small intestinal lumen and mucosa, caecal contents and plasma were determined by LC/MS. Q3G was not hydrolysed in the stomach, but deglycosylation and further metabolism occurred in the small intestinal mucosa. At least 17 flavonoid glucuronides were identified in the lumen and mucosa, with evidence of time‐dependent changes such as de‐ and re‐glucuronidation. Quercetin mono‐sulphate was also detected in the small intestinal contents. Metabolites were still present in tissue and plasma 24 h after feeding. There was also evidence of complex microbial processing of Q3G in the caecal lumen with the appearance of at least one methylquercetin‐mono‐glucuronide, mono‐sulphate unique to this site in the gut, together with phenolic acid derivatives. Intestinal flavonoid metabolism is thus a very complex process in mammals, involving both enterocytes and bacteria. Copyright © 2004 Society of Chemical Industry     

In vitro DNA damage protection and anti‐inflammatory effects of Tartary buckwheats (Fagopyrum tataricum L. Gaertn) fermented by filamentous fungi

The present work was designed to investigate the phenolic profiles, DNA damage protection and anti‐inflammatory effects of Tartary buckwheat fermented by Rhizopus oryzae 40469, Rhizopus oryzae 40503 and Rhizopus oligosporus 3152. Six phenolic compounds were characterised and quantified. Regardless of fermentation, rutin was the dominant phenolic substance in Tartary buckwheat. Fermentation significantly enhanced total phenolic and flavonoid contents, as well as DNA scission protection. Rhizopus oryzae 40469‐fermented sample had the highest content of phenolics, while R. oligosporus 3152‐fermented sample had the strongest inhibitory effect on DNA scission. Tartary buckwheat, regardless of fermentation, inhibited nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) mRNA levels in LPS‐induced RAW 264.7 cells. Moreover, the sample fermented with R. oryzae 40503 had the strongest inhibitory activity. Those results indicated that fermented Tartary buckwheat has potential applications as a novel nutraceutical or functional food for preventing DNA damage‐induced disease and inflammation.     

Biological evaluation and quantitative analysis of antioxidant compounds in pulps of the Amazonian fruits bacuri (Platonia insignis Mart.), ingá (Inga edulis Mart.), and uchi (Sacoglottis uchi Huber) by UHPLC‐ESI‐MS/MS

Bacuri, ingá, and uchi are Amazon fruits consumed specially in the North region of Brazil. Due to their large consumption and the lack of knowledge regarding its chemical composition, these fruits were studied in relation to their Antioxidant chemical constitution. The total phenolic content ranged from 3.86 ± 0.47 to 33.38 ± 1.51 mg GAE/100 g, and the total flavonoid content ranged from 1.75 ± 0.22 to 19.44 ± 0.87 mg QUERE/100 g, where the contents showed a significant correlation with DPPH and ABTS antioxidant assays. Thus, UHPLC‐MS/MS was applied do quantify selected compounds, been citric acid the most abundant for all fruits. Furthermore, samples were screened for their α‐glycosidase and lipase inhibitory effects, in addition to their antimicrobial potentials. Bacuri showed the highest antioxidant and α‐glycosidase inhibitory capacity (IC₅₀ 15.20 μg/mL), whereas uchi and its main metabolite bergenin displayed moderate antimicrobial activities. The results shed light into the potentials of Amazonian fruit sources.

Practical applications

Plant phenolics are essential components of functional foods, due to their antioxidant and enzyme inhibition activities, which are directly linked to several diseases prevention. This is the first study about the quantification of antioxidant compounds in the Amazonian fruits: bacuri, ingá, and uchi. Although they are quite consumed in the North region of Brazil, there are no bio‐products made from them. This study aimed to elucidate the knowledge about the chemical composition and potentialities within these fruits with the practical purpose of highlighting them to future commercial applications. In addition, once we indicate their capabilities, we contribute with local populations in respect to the production of such fruits, which still is a family activity.