Anthocyanin Extraction from Jaboticaba Skin (Myrciaria cauliflora Berg.) Using Conventional and Non-Conventional Methods.

This study evaluated the effect of different extraction technologies and conditions in order to obtain jaboticaba skin extracts. Firstly, the skins were extracted by conventional extraction, according to a rotatable central composite design, varying ethanol concentration, solid:liquid ratio, and temperature. Next, ultrasound-assisted extraction was performed using different power densities and times. Finally, high-pressure extractions were performed with varying pressures and times. For agitated bed extraction, the highest anthocyanin content was observed for ethanol concentrations varying between 60% and 80%. Thus, the independent variables which more influenced anthocyanin content were ethanol concentration and solid:liquid ratio. Folin-Ciocalteu reducing capacity was linearly affected by the increase in temperature. Ethanol concentration was the variable that most influenced ABTS+. On the other hand, the increase in ethanol concentration decreased the antioxidant capacity by ABTS+. Considering the ultrasound extraction, increasing its power did not affect total monomeric anthocyanins content, while the increase in process time had better yields. The highest antioxidant capacity and total monomeric anthocyanins were found for the highest extraction time. Similarly, with ultrasound, the increase in high hydrostatic-assisted extraction time positively influenced anthocyanin content and antioxidant capacity. As a result, the ultrasound-assisted method was found to be the best extraction technology for anthocyanins recovery.

Myrcia eriopus DC. (Myrtaceae) fruits, a new endemic Brazilian source of bioactive anthocyanins.

Myrcia eriopus DC. (Myrtaceae) is a native and endemic Brazilian species, and there is no information about its chemical composition. In our study, five different anthocyanins and two other phenolic compounds were described for the first time in M. eriopus fruits. Delphinidin 3-O-glucoside (1), cyanidin 3-O-glucoside (2), petunidin 3-O-glucoside (3), peonidin 3-O-glucoside (4), malvidin 3-O-glucoside (5), gallic acid (6) and myricetin (7) were identified by offline system RP-HPLC-DAD/ESI-QTOF-MS and compared to the scientific literature. Furthermore, the lyophilized powder of M. eriopus fruits showed a high anthocyanin content (1878.14 mg cy-3-glu eqv/100 g f.w.), with greater levels of compounds 1 and 3, and an antioxidant potential in DPPH and ABTS assays (EC50 2419 µg/mL and 339 µmol Trolox/g f.w.), results superior to other non-conventional Brazilian fruits. This first report about the chemical composition of M. eriopus fruit reveals the potential of this fruit as a new source of bioactive anthocyanins.

Processing tomato waste as a potential bioactive compounds source: phenolic compounds, antioxidant capacity and bioacessibility studies / Resíduo do processamento do tomate como potencial fonte de compostos bioativos: compostos fenólicos, capacidade antioxidante e bioacessibilidade

A comparative study was perfomed with conventional and ultrasound assisted extraction on tomato processing waste. Ultrasound extraction exhibited slightly higher phenolic and flavonoids content, as well as higher ABTS + radical scavenging capacity (4.63 mg GAE.g-1, 0.96 mg RUE.g-1 and 27.90 µmol TE.g -1 respectively). On both extracts, a high percentage of flavonoids was lost during simulated digestion, resulting on a bioacessibility of approximately 13 %. Extracts presented good stability during storage conditions, which indicates a possible technological application.

Foi realizado um estudo comparativo com a extração convencional e assistida por ultrassom em resíduos do processamento de tomate. A extração ultrassônica exibiu teor de fenólicos e flavonóides ligeiramente maiores, bem como maior capacidade antioxidante ABTS + (4,63 mg AG.g-1, 0,96 mg RUE.g-1 e 27,90 µmol TE.g -1, respectivamente). Em ambos os extratos, uma alta porcentagem de flavonóides foi perdida durante a digestão simulada, resultando em uma bioacessibilidade de aproximadamente 13%. Os extratos apresentaram boa estabilidade durante as condições de armazenamento, o que indica uma possível aplicação tecnológica.

Determination of the Phytochemical Composition and Antioxidant Potential of Eugenia copacabanensis and Myrciaria tenella Leaves (Myrtaceae) Using a Saccharomyces cerevisiae Model.

Eugenia copacabanensis and Myrciaria tenella are present in restingas of the Atlantic Forest, but little information is available about their chemical and biological potential. In this context, the hexane, dichloromethane, ethyl acetate and butanol fractions from the leaves of methanolic extract were analyzed by GC/MS and HPLC-DAD and the antioxidant potential was determined by DPPH and ABTS assays and using a Saccharomyces cerevisiae model. Dereplication allowed the identification of 68 compounds, 42 and 41 of which, respectively, are first reported here for E. copacabanensis and M. tenella. In vivo results revealed that the ethyl acetate and butanol fractions showed expressive antioxidant protection in the BY4741 and Δgsh1 strains, with greater impact on glutathione-deficient cells. With a high diversity of phenolic compounds, these polar fractions of E. copacabanensis and M. tenella leaves are potential protectors against intracellular oxidative stress.

Antiproliferative Activity on Human Colon Adenocarcinoma Cells and In Vitro Antioxidant Effect of Anthocyanin-Rich Extracts from Peels of Species of the Myrtaceae Family.

There is a significant indication of the beneficial health effects of fruit rich diets. Fruits of native plant species have noticeably different phytochemicals and bioactive effects. The aim of this work was to characterize and compare the constituents of jabuticaba (Myrciaria jaboticaba, MJ), jamun-berry (Syzygium cumini, SC), and malay-apple (Syzygium malaccense, SM) extracts and their influence on antioxidant activity in vitro and antiproliferative effects on human colon adenocarcinoma cells. According to the results, dried peel powders (DP) have a high anthocyanin content, phenolic compounds, and antioxidant activity when compared to freeze dried extracts (FD). M. jaboticaba dried peel powder extract had a higher total anthocyanin and phenolic compounds content (802.90 ± 1.93 and 2152.92 ± 43.95 mg/100 g, respectively). A reduction in cell viability of HT-29 cells after treatment with M. jaboticaba extracts (DP-MJ and FD-MJ) was observed via MTT assay. Flow cytometry showed that the treatment with the anthocyanin-rich extracts from MJ, SC, and SM had an inhibitory impact on cell development due to G2/M arrest and caused a rise in apoptotic cells in relation to the control group. The findings of this study highlight the potential of peel powders from Myrtaceae fruits as an important source of natural antioxidants and a protective effect against colon adenocarcinoma.

Beneficial effects of anthocyanin-rich peels of Myrtaceae fruits on chemically-induced liver fibrosis and carcinogenesis in mice.

Hepatocellular carcinoma (HCC) arising from fibrosis/cirrhosis is the most common type of primary liver cancer. Conversely, a higher intake of fruits and vegetables might play a protective role in HCC risk. Recently, Myrtaceae family tropical fruits have raised great interest due to the high levels of anthocyanins especially in their peels, which are usually discarded upon consumption. Anthocyanins are antioxidant pigments known to have beneficial effects in vivo/in vitro cancer bioassays. Thus, we evaluated whether dietary Myrciaria jaboticaba, Syzygium cumini, and Syzygium malaccense fruit peel powders reduce fibrosis and hepatocarcinogenesis in mice. Female C3H/HeJ mice were submitted to the model of diethylnitrosamine/carbon tetrachloride-induced liver fibrosis and carcinogenesis. Concomitantly, mice received a basal diet containing 2% of M. jaboticaba, S. cumini, or S. malaccense fruit peel powders, obtained by convective drying, for 10 weeks. M. jaboticaba peel powder showed the highest levels of total anthocyanins, while S. cumini peel powder displayed the greatest diversity of these pigments. All Myrtaceae family peel powders reduced the serum levels of the liver injury marker alanine aminotransferase. M. jaboticaba peel feeding reduced the incidence of liver preneoplastic foci, hepatocyte proliferation (Ki-67), and the protein levels of hepato-mitogen tumor necrosis factor-alpha (TNF-α). M. jaboticaba peel feeding also diminished liver lipid peroxidation and increased total glutathione levels. S. cumini peel feeding reduced hepatic collagen, lipid peroxidation, and TNF-α levels while increased catalase activity. Although S. malaccense peel powder, which displayed the lowest anthocyanin levels, decreased oxidative stress, and cytokine levels, no effects were observed on liver fibrosis or preneoplastic lesion outcomes. Findings indicate a protective effect of anthocyanin-rich M. jaboticaba and S. cumini peel powder feeding on preneoplastic lesion development and fibrosis, respectively. Results indicate that differential biological responses may be attributed to distinct anthocyanin profiles and levels, assigning a functional/market value to the underutilized peel fraction.

Grape seed pomace as a valuable source of antioxidant fibers.

BACKGROUND: Grape seed pomace is a valuable by-product from winery/oil extraction industries and a potential source of bioactive compounds. Hot water extraction is the most widely used technology for polysaccharide recovery from plant and seed sources. To obtain an antioxidant fiber-rich extract (AFE) from defatted grape seed pomace, seed:water ratio (1:10-1:20) and extraction temperature (70-90 °C) effects on extraction yield, total sugars, total phenolic compounds and condensed tannins were investigated. RESULTS: The best extraction results were achieved at the highest seed:water ratio and temperature. At these conditions, the extraction yield and total sugar content of the freeze-dried AFE were 100.1 g kg-1 and 725.3 g kg-1 , respectively. The AFE presented high total phenolic content (16.2 g GAE kg-1 ), condensed tannins (515.1 mg CAT kg-1 ), soluble (219.1 g kg-1 ) and insoluble fibers (132.4 g kg-1 ), besides protein (171.1 g kg-1 ) and ash (152.6 g kg-1 ). The antioxidant capacity of the AFE was 382.7, 823.7 and 1439.4 µmol Trolox g-1 for DPPH, ABTS and ORAC methods. CONCLUSION: The AFE was shown to be not only an interesting source of fiber with antioxidant capacity, which could become a potential foodstuff, but also an ecofriendly and sustainable alternative to use grape seed pomace. © 2019 Society of Chemical Industry.

Enzymatic production of xylooligosaccharides from Brazilian Syrah grape pomace flour: a green alternative to conventional methods for adding value to agricultural by- products.

BACKGROUND: The aim of this work was to determine the most favorable conditions for the production of xylooligosaccharides (XOS) from Brazilian Syrah grape pomace. Chemical processes were performed using a rotatable central composite design where the concentration of sulfuric acid or sodium hydroxide and the grape pomace flour/solvent mass ratio were the dependent variables. Enzymatic production was also evaluated using xylanase produced by Aspergillus niger 3T5B8 and Viscozyme® enzymatic commercial cocktail. RESULTS: Chemical extraction allowed to recover 21.8-74.6% and 5.2-96.3% of total XOS for acidic and alkaline processes respectively. Enzymatic production extracted up to 88.68 ± 0.12% of total XOS using xylanase and up to 84.09 ± 2.40% with Viscozyme® . CONCLUSION: The present study demonstrated different feasible methods to produce high-added-value molecules, i.e. XOS, from Syrah grape pomace flour, valorizing this major by-product. The use of enzymatic cocktails demonstrated to be an alternative to the conventional methods, allowing to obtain an eco-friendly and sustainable grape pomace extract. © 2018 Society of Chemical Industry.

Antioxidant Compounds Recovery from Juçara Residue by Thermal Assisted Extraction.

This study aimed to recover bioactive compounds by solid-liquid extraction from the agro-industrial residue obtained during juçara fruits processing into pulp. A preliminary study using different solvents (methanol, ethanol and water) indicated ethanol in aqueous solution as the best solvent for antioxidants recovery. Then, a Box-Behnken design was applied considering as independent variables the solvent composition (30-70% ethanol in water), temperature (30-70 °C) and time (30-60 min), in order to evaluate the effects of these factors on antioxidant activity in juçara extract. Results showed that the extracts with higher antioxidant activity were obtained using 30% ethanol at 70 °C for 60 min; measurements included ABTS and DPPH assays, determination of total phenolic content and total monomeric anthocyanins. Furthermore, the effect of pH in antioxidants recovery was evaluated. For this purpose, the 30% ethanol solution was acidified to pH 1 and 2 with HCl. Principal component analysis showed the formation of three distinct groups: one characterized by high bioactive compounds content (pH 1.0), another with superior antioxidant activity (pH 5.75, non-acidified), and finally the group at pH 2 presenting the worst concentrations in the evaluated responses. HPLC analysis showed the presence of cyanidin-3-O-rutinoside and cyanidin-3-O-glucoside in the extracts. Therefore, the conventional solid-liquid extraction using renewable solvent can be successfully applied to recover bioactive compounds from juçara residue, which can be used by different food industries.

Chemical characterization of Myrciaria floribunda (H. West ex Willd) fruit.

M. floribunda fruit was studied to characterize its chemical composition. The chemical composition, bioactive compounds, antioxidant activity and volatiles of the fruit were determined. The chemical composition was determined according to AOAC and AOCS, the bioactive compounds by HPLC, the volatiles by GCMS and the antioxidant activity by ABTS+ and DPPH methods. The chemical composition of the freeze-dried fruit was 1.89 g·100 g-1, 2.43 g·100 g-1, 4.78 g·100 g-1 and 90.89 g·100 g-1 of ashes, lipids, proteins and total carbohydrates on a dry base, respectively. The concentration of the carotenoids was 52.22 mg·100 g-1 and for the flavonoid rutin was 78.56 mg·100 g-1. The gallic and ellagic acid contents were 5.45 mg·g-1 and 2.21 mg·g-1, respectively. The cis-ß-ocimene corresponded to 50.90% of the volatiles. The antioxidant activity by ABTS+ method was 550.14 µmol Trolox·g-1 and by the DPPH method the EC50 was 85.68 g·g-1. The fruits presented relevant antioxidant activity, a high concentration of carotenoids and of rutin.

Identification and quantification of anthocyanins in fruits from Neomitranthes obscura (DC.) N. Silveira an endemic specie from Brazil by comparison of chromatographic methodologies.

Neomitranthes obscura (DC.) N. Silveira is a Brazilian fruit belonging to the Myrtaceae family that contains anthocyanins in the peel and was studied for the first time in this work. Delphinidin-3-O-galactoside, delphinidin-3-O-glucoside, cyanidin-3-O-galactoside, cyanidin-3-O-glucoside, cyanidin-3-O-arabinoside, petunidin-3-O-glucoside, pelargonidin-3-O-glucoside, peonidin-3-O-galactoside, peonidin-3-O-glucoside, cyanidin-3-O-xyloside were separated and identified by LC/DAD/MS and by co-elution with standards. Reliable quantification of anthocyanins in the mature fruits was performed by HPLC/DAD using weighted linear regression model from 0.05 to 50mg of cyaniding-3-O-glucoside L(-1) because it gave better fit quality than least squares linear regression. Good precision and accuracy were obtained. The total anthocyanin content of mature fruits was 263.6 ± 8.2 mg of cyanidin-3-O-glucoside equivalents 100 g(-1) fresh weight, which was in the same range found in literature for anthocyanin rich fruits.

Obtenção de padrões de cis-licopeno e beta-criptoxantina para cromatografia líquida de alta eficiência a partir de melão-de-São-Caetano e caqui / Obtaining cis-lycopene and beta-cryptoxanthin standards for high performance liquid chromatography from bitter melon and persimmon

A detecção e quantificação de carotenóides em alimentos por cromatografia líquida de alta eficiência (CLAE) demanda de padrões analíticos com alto grau de pureza. A aquisição comercial destes padrões é morosa e dispendiosa. Além disso, determinados diasteroisômeros não estão disponíveis no mercado e alterações dos compostos podem ocorrer durante seu transporte. Desta forma, o objetivo deste trabalho foi obter isômeros cis-licopeno a partir de licopeno todo-trans de melão-de-São-Caetano (Momordica charantia L.) e beta-criptoxantina a partir de caqui (Diospyros kaki L.) para utilização como padrões analíticos na análise de alimentos. Licopeno todo-trans extraído do arilo de sementes de melão-de-São-Caetano foi convertido a cis-licopeno. A isomerização e separação das frações contendo isômeros do licopeno foram realizadas em coluna cromatográfica aberta de sílica ativada e a verificação da isomerização e o isolamento foram realizados por CLAE. Foram detectados 94,2% de licopeno todo-trans entre os carotenóides totais dos arilos de sementes. A isomerização em coluna de sílica aberta ativada produziu 29 isômeros ¬cis-licopeno em três frações coletadas. Nas primeiras frações de melão-de-São-Caetano e de caqui foram isolados um isômero cis-licopeno e beta-criptoxantina com pureza de 91,3% e 92,8%, respectivamente, o que permite seu uso como padrões analíticos para análises. Após 1 ano conservados à -18 oC em ampola de borossilicato selada à vácuo, em ambiente escuro, não houve alteração significativa nas concentrações do cis-licopeno e da beta-criptoxantina, permitindo ainda seu uso como padrões analíticos. A metodologia empregada mostrou-se viável para a conversão de licopeno todo-trans em cis-licopenos e para o isolamento e purificação de padrões analíticos para CLAE.

Detection and quantification of carotenoids in foods can be carried out by high performance liquid chromatography (HPLC), but analytical standards must be employed. However, these analytical standards are expensive, some isomers are not available for trade, time consuming between purchase and reception and chemical changes may occur during long transportation. Therefore, the objective of this study was to obtain cis-lycopene isomers from all-trans lycopene present in bitter melon (Momordica charantia L.) and beta-cryptoxanthin from persimmon (Diospyros kaki L.), for use as analytical standards in foods analysis. All-trans lycopene extracted from bitter melon seed arils was converted to cis-lycopene. The isomerization and separation of the fractions containing cis-isomers were done in silica column. Confirmation of isomerization and isolation of cis-lycopene were performed by HPLC. A total of 94.2% of all-trans lycopene were detected in the seed arils. Isomerization in silica column produced 29 cis-lycopene isomers in 3 fractions collected. In the first fraction, a cis-lycopene with a purity of 91.3% was isolated which allows its use as analytical standard for analysis using HPLC. After sample preparation, ?-cryptoxanthin was isolated by silica column. Analysis by HPLC revelead ?-cryptoxanthin with purity of 92.8%. After one year stored at -18 °C in sealed borosilicate glass ampoule under vacuum, in the dark,, no significant change in concentration of cis-lycopene and ?-cryptoxanthin occured, still allowing them use as analytical standards. The methodology was feasible for the conversion of all-trans lycopene to cis-lycopene and for the isolation and purification of analytical standards by HPLC.