184 research outputs found
Estudo do comportamento reológico e colorimétrico de misturas ternárias e sistemas pécticos de polpas de morango, amora-preta e franboesa /
Orientadora : Maria Lucia MassonCo-orientadoras : Maria Rita Sierakowski e Ivanise G. BrancoTese (doutotrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduaçao em Tecnologia de Alimentos. Defesa: Curitiba, 2007Inclui bibliografi
Comportamento reológico e fracionamento péctico das polpas integrais de araça (Psidium catlleianum sabine) e amora-preta (Rubus spp)
Orientadora: Maria Lucia MassonCo-orientadora: Maria Rita SierakowskiInclui apendiceDissertaçao (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduaçao em Tecnologia de Alimentos. Defesa: Curitiba, 2005Inclui bibliografiaResumo: O objetivo deste trabalho foi avaliar o efeito do tratamento térmico sobre o comportamento reológico e as frações pécticas das polpas integrais de araçá (Psidium cattleianum sabine) e amora-preta (Rubus spp). O araçá e amora-preta foram processadas em despolpadeiras (araçá - tela de 1,5mm) e amora-preta (1,0mm e 0,5mm). Essas aberturas foram escolhidas com o objetivo de se obter uma polpa homogênea. As medidas reológicas foram realizadas em reômetros Brookfield, modelo DV-III+ para polpa de araçá e modelo LVDV-III para a polpa de amora-preta, com adaptador para pequena quantidade de amostra, sendo as medidas reológicas realizadas em uma faixa de temperatura de 10-60oC. Os dados reológicos foram ajustados ao modelo da lei da potência para a polpa de araçá e ao modelo de Herschel- Bulkley para a polpa de amora-preta. Uma quantidade representativa de amostra das polpas (30g), após o tratamento térmico (15 minutos), foi usada para a obtenção de quatro frações (PSA-fração solúvel em água, PSO-fração solúvel em oxalato de potássio, PSAC-fração solúvel em ácido clorídrico e PSH-fração solúvel em hidróxido de sódio). O conteúdo de ácido galacturônico dessas frações foi determinado pela utilização de um espectrofotômetro (520nm) pelo método alcalino do m-hidroxibifinil. A polpas de araçá e de amora-preta apresentaram um comportamento não-newtoniano, com caráter pseudoplástico. O modelo da lei da potência e de Herschel-Bulkley descreveram bem o comportamento reológico da polpa de araçá e amora-preta, respectivamente, apresentando altos coeficientes de determinação. A viscosidade aparente das polpas diminuiu com o aumento da temperatura e com a taxa de cisalhamento, no entanto, a polpa de araçá apresentou uma tendência de aumento a 60oC. A energia de ativação calculada para a polpa de araçá a 50 s-1 foi de 11,03 KJmol-1 e para a polpa de amorapreta foi de de 18,27 KJmol-1. Houve diferença significativa (p<0,05) na quantidade de ácido galacturônico nas frações PSA, PSO, PSAC e PSH para polpa de araçá e amorapreta com o aumento da temperatura, sendo que ambas as polpas apresentaram na quantidade de ácido galacturônico uma tendência de decréscimo na fração insolúvel em água (PIA) e de aumento na fração solúvel em água (PSA), com o aumento da temperatura. As viscosidades aparentes das polpas mostraram-se ser altamente dependentes da fração de pectina solúvel em água (PSA), ou seja, com o aumento da quantidade de ácido galacturônico dessa fração devido a influência da temperatura, ocorre uma diminuição significativa no valor da viscosidade aparente. Palavras-chave: Reologia, temperatura, viscosidade aparente, araçá, amora-preta.Abstract: The aim of this work was to evaluate the effect of heat treatment on rheological behavior and pectic fractions of whole cattley guava (Psidium cattleianum) and blackberry (Rubus spp) pulps. The cattley guava and blackberry fruits were processed in a depulper (cattley guava - 1,5mm screen) and blackberry (1,0mm and 0,5mm screen). This mesh was chosen in order to obtain an uniform consistency. The rheological measurements were carried out with a concentric cylinder Brookfield rheometer, model DV-III for cattley guava pulp and model LVDV-III for blackberry pulp, using a small sample adapter in a temperature range of 10-60oC. The rheological data of the cattley guava pulp were fitted according to the power law model and the blackberry pulp data were fitted according to Herschel-Bulkley model. A representative sample of the pulps (30g), after the heat treatment (15 minutes), was used to obtain four fractions of pectic substances (PSAwater insoluble fraction, PSO-oxalate soluble fraction, PSAC-acid soluble fraction and PSH-alkali soluble fraction). The galacturonic acid content of this fractions was spectrophotometrically determined (520nm) by the alkaline m-hydroxybiphenyl method. The cattley guava and blackberry pulp showed a non-Newtonian behavior, with shear thinning character. The power law model and Herschel-Bulkley model described well the rheological behavior of the cattley guava and blackberry pulp, respectively, with high determination coefficients. The apparent viscosity of the pulps decreased with the temperature and shear rate increase, however, the cattley guava pulp showed an increase tendency up to 60ºC. The activation energy value calculated to the cattley guava pulp at 50 s-1 was 11,03 KJmol-1 and for the blackberry pulp was 18,27 KJmol-1. There was significative difference (p<0,05) in the amount of galacturonic acid for the fractions PSA, PSO, PSAC and PSH to the cattley guava and blackberry pulp with the temperature increase, whereas both pulps showed a decrease tendency in the amount of galacturonic acid to the water insoluble fraction (PIA) and an increase tendency to the soluble water fraction (PSA), with the temperature increase. The apparent viscosity of the pulps showed to be highly dependent on the water soluble fraction (PSA), in other words, with the increase in the amount of galacturonic acid of this fraction due to the temperature influence, a significative decrease on the apparent viscosity value ocurred. Keywords: Rheology, temperature, apparent viscosity, cattley guava, blackberry
Utjecaj optimiranja postupka proizvodnje bakterijske nanoceluloze na rast kulture i koncentraciju biološki aktivnih spojeva
Research background. Research into bacterial cellulose production has been growing rapidly in recent years, as it has a potential use in various applications, such as in the medical and food industries. Previous studies have focused on optimising the production process through various methods, such as using different carbon sources and manipulating environmental conditions. However, further research is still needed to optimise the production process and understand the underlying mechanisms of bacterial cellulose synthesis.
Experimental approach. We used Plackett-Burman and Box-Behnken experimental designs to analyse the effect of different factors on bacterial cellulose production. The fermentation kinetics of the optimised medium was analysed, and the produced cellulose was characterised. This approach was used because it allows the identification of significant factors influencing bacterial cellulose growth, the optimisation of the culture medium and the characterisation of the produced cellulose.
Results and conclusions. The results showed that higher sucrose concentrations, higher kombucha volume fractions and a smaller size of the symbiotic culture of bacteria and yeast were the most important factors for the improvement of bacterial cellulose production, while the other factors had no relevant influence. The optimised medium showed an increase in the concentrations of total phenolic compounds and total flavonoids as well as significant antioxidant activity. The produced pure bacterial cellulose had a high water absorption capacity as well as high crystallinity and thermal stability.
Novelty and scientific contribution. The study makes an important scientific contribution by optimising the culture medium to produce bacterial cellulose more productively and efficiently. The optimised medium can be used for the production of a kombucha-like beverage with a high content of bioactive compounds and for the production of bacterial cellulose with high crystallinity and thermal stability. Additionally, the study highlights the potential of bacterial cellulose as a highly water-absorbent material with applications in areas such as packaging and biomedical engineering.Pozadina istraživanja. Posljednjih godina se sve više istražuje postupak proizvodnje bakterijske celuloze, jer ima višestruku mogućnost primjene, kao npr. u medicini i prehrambenoj industriji. Dosadašnja su istraživanja prvenstveno bila usmjerena na optimiranje postupka proizvodnje različitim metodama, kao što su primjena različitih izvora ugljika te podešavanje uvjeta uzgoja. Međutim, potrebno je dodatno ispitati optimiranje postupka proizvodnje i produbiti razumijevanje mehanizma sinteze bakterijske celuloze.
Eksperimentalni pristup. Koristili smo Plackett-Burmanov i Box-Behnkenov eksperimentalni dizajn za određivanje utjecaja različitih faktora na proizvodnju bakterijske celuloze. Ispitana je kinetika fermentacije u optimiranoj podlozi, te je okarakterizirana dobivena celuloza. Odabrali smo ovaj pristup jer omogućava identifikaciju bitnih čimbenika koji utječu na rast bakterijske celuloze, optimiranje podloge za rast i karakterizaciju dobivene celuloze.
Rezultati i zaključci. Rezultati pokazuju da su veća koncentracija šećera, veći volumni udjel kombuche i manja veličina simbiotičke kulture bakterija i kvasaca najbitniji faktori povećanja proizvodnje bakterijske celuloze, dok ostali faktori nisu imali bitan utjecaj. U optimiranoj se podlozi povećala koncentracija ukupnih fenolnih spojeva i ukupnih flavonoida, te se bitno povećala antioksidacijska aktivnost dobivenog napitka. Dobivena čista bakterijska celuloza imala je veliki kapacitet apsorpcije vode, te visoku kristaliničnost i toplinsku stabilnost.
Novina i znanstveni doprinos. Bitan znanstveni doprinos ovoga rada je u optimiranju podloge za učinkovitiju i veću proizvodnju bakterijske celuloze. Optimirana je podloga prikladna za proizvodnju napitka sličnog kombuchi s velikom koncentracijom bioaktivnih spojeva te proizvodnju termostabilne i visoko kristalinične bakterijske celuloze. Osim toga, rezultati pokazuju da proizvedena bakterijska celuloza ima veliku moć upijanja vode, pa se može upotrijebiti u proizvodnji ambalaže i biomedicinskom inženjeringu
New phytochemicals as potential human anti-aging compounds: reality, promise, and challenges
Aging is an inevitable process influenced by genetic, lifestyle, and environmental factors. Indirect evidence shows that several phytochemicals can have anti-aging capabilities, although direct evidence in this field is still limited. This report aims to provide a critical review on aspects related to the use of novel phytochemicals as anti-aging agents, to discuss the obstacles found when performing most anti-aging study protocols in humans, and to analyze future perspectives. In addition to the extensively studied resveratrol, epicatechin, quercetin, and curcumin, new phytochemicals have been reported to act as anti-aging agents, such as the amino acid L-theanine isolated from green tea, and the lignans arctigenin and matairesinol isolated from Arctium lappa seeds. Furthermore, this review discusses the application of several new extracts rich in phytochemicals with potential use in anti-aging therapies. Finally, this review also discusses the most important biomarkers to test anti-aging interventions, the necessity of conducting epidemiological studies and the need of clinical trials with adequate study protocols for humans.R.C.G. Correa thanks Coordena¸c~ao de Aperfei¸coamento do Pessoal do
Ensino Superior (CAPES) and Funda¸c~ao Arauc aria for the financial support
provided for her postgraduate studies in Federal Technological University
of Paran a (contract 100/2014). R.M. Peralta (Project number
307944/2015-8), C.W.I. Haminiuk (Project number 303238/2013-5), and
A. Bracht (Project number 302615/2011-3) are research grant recipients of
Conselho Nacional de Desenvolvimento CientÍfico e Tecnologia (CNPq).
The authors are also grateful to (FCT, Portugal) and FEDER-COMPETE/
QREN/EU for financial support through the research project PEst-OE/
AGR/UI0690/2014.info:eu-repo/semantics/publishedVersio
Merlot grape pomace hydroalcoholic extract improves the oxidative and inflammatory states of rats with adjuvant-induced arthritis
Grape pomace is an agro-industrial residue produced worldwide. The purpose of this study was to identify and quantify the main phenolics present in an hydroalcohlic extract of a Merlot grape pomace and to investigate its effect on the oxidative and inflammatory states of adjuvant-induced arthritic rats. Daily doses of 250 mg of the extract per kg body weight were administered during 23 days. Several oxidative stress indicators in arthritic rats were maintained at their normal or closely normal levels in the plasma, liver and brain by the treatment. Additionally, the grape pomace also showed significant anti-inflammatory effects. From the 25 phenolics identified in the grape pomace extract the most abundant ones were catechin and catechin derivatives, which are possibly the most important antioxidant agents. The results suggest a potential applicability of the Merlot grape pomace hydroalcoholic extract in the improvement of the oxidative and inflammatory states in arthritic patients.The authors which to thank Anacharis Babeto de Sá-Nakanishi,
Jurandir Fernando Comar and Leomara Floriano Ribeiro for their
expert technical assistance.
This work was financially supported by grants from the Conselho
Nacional de Desenvolvimento Científico e Tecnológico (CNPq,
Proc. 302615/2011-3 and Proc. 307944/2015-8) and Fundação Araucária
(Proc. 215/2014). Andréia A. Soares and Rúbia C. G. Corrêa
were post-doc fellowship recipients of the Coordenação do Aperfeiçoamento
de Pessoal do Ensino Superior (CAPES) and Fundação
Araucária.
The authors are also thankful to the Foundation for Science and
Technology (FCT, Portugal) and FEDER under Program PT2020 for
financial support to CIMO (UID/AGR/00690/2013) and L. Barros
(SFRH/BPD/107855/2015) grant. To POCI-01-0145-FEDER-006984
(LA LSRE-LCM), funded by ERDF, through POCI-COMPETE2020
and FCT.info:eu-repo/semantics/publishedVersio
Açaí Seeds as a Prospective Biosorbent for Acid Dyes Removal
In this study, were used residual Açaí seeds as a biosorbent for two textile dyes (Acid Yellow 219 (AY) and Acid Red 361 (AR)), in single and binary solutions.
Further, kinetic and isothermal studies were carried to evaluate if the chemical modifications in the Açaí seeds would promote an increase in biosorption. Kinetic assays for all solutions showed that more than 50 % of the dyes were removed in the first 15 minutes. The acid treatment of the biosorbent increased the removal of acid dyes in solution by 46 % and 32 %, respectively. In conclusion, chemically modified Açaí seeds showed high capacity for the removal of textile dyes in single (AY qe = 1.40 mg g-1; AR qe = 1.76 mg g–1) and multi-component solutions (AY MIX qe = 2.09 mg g–1; AR MIX qe = 2.23 mg g–1). These results demonstrate that Açaí seeds can be applied in an inexpensive strategy for removing pollutants (single or binary solutions) from wastewater.
This work is licensed under a Creative Commons Attribution 4.0 International License
Stability and biological activity of Merlot (Vitis vinifera) grape pomace phytochemicals after simulated in vitro gastrointestinal digestion and colonic fermentation
Grape pomace is an abundant/accessible food industry by-product that contains a wide range of phenolic compounds, which have been related to several health benefits and bioactivities. The aim of this study was to mimic the gastrointestinal digestion and the colonic fermentation of Merlot grape pomace, in order to unravel possible phytochemical contents reductions and the processes associated with them, as a tentative to relate the phenolic compound profiles of the extracts with their biological properties. LC-DAD-ESI/MS suggested that the in vitro digestion process promoted drastic qualitative and quantitative reductions in the phenolic compounds profile of the Merlot grape pomace crude extract. Such alterations could be related to the decreases of some bioactivities of the extract, which seems to be the case of antioxidant and antibacterial properties, although not in a directly proportional manner. However, the simulated colonic fermentation seems to have a positive effect over the extract's antiproliferative potential.R.C.G. Correa thank Coordenação de Aperfeiçoamento do Pessoal do Ensino Superior (CAPES) and Fundação Araucária for the financial support provided for her post-graduate studies in Federal University of Technology - Paraná (contract 100/2014). Authors C.G. Kato and V.G. Correa thank CAPES for the financial support provided for their post-graduate studies in the State University of Maringá. R.M. Peralta (Project number 307944/2015-8) and C.W.I. Haminiuk (project number 303238/2013-5 and 304978/2016-7) are research grant recipients of Conselho Nacional de Desenvolvimento Científico e Tecnologia (CNPq). The authors are also thankful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Program PT2020 for financial support to CIMO (UID/AGR/00690/2013), L. Barros (SFRH/BPD/107855/2015) and M.I. Dias (SFRH/BD/84485/2012) grants. To POCI-01-0145-FEDER-006984 (LA LSRE-LCM), funded by ERDF, through POCI-COMPETE2020 and FCT.info:eu-repo/semantics/publishedVersio
Bioactive profile of edible nasturtium and rose flowers during simulated gastrointestinal digestion
not widely explored. The gastrointestinal environment can modify these compounds, resulting in new combinations
with different bioactivity. This study aimed to evaluate the effects of simulated gastrointestinal digestion
(SGD) on rose and nasturtium flower extracts. Using UPLC-HRMS, 38 phenolic compounds were identified, and
the SGD caused significant changes, mainly in the glycosylated phenolic. Furthermore, antioxidant activity was
correlated with the increase in the concentrations of some polyphenols. Tested Gram-negative bacteria showed
sensitivity to the flower extracts; their growth was inhibited by up to 82.7%. SGD interrupted the bacterial
growth inhibition power of the rose extracts. On the other hand, an increase in inhibition ranging from 52.25 to
54.72% was found for nasturtium extracts, correlated to the behavior of some bioactive. Hence, SGD resulted in
significant changes in phenolic profiles of the edible flowers, increasing antioxidant activity and changing
antimicrobial effects.The authors would like to thank the Federal University of Parana
(UFPR), Federal University of Technology - Parana (UTFPR), Coordination
of Superior Level Staff Improvement (CAPES, Contract
88881.624585/2021-01), and the National Council for Scientific and
Technological Development (CNPq, Grant number 304722/2019-7) for
financial support. In addition, the authors are grateful to the Foundation
for Science and Technology (FCT, Portugal) for the contracts of J. Pinela
(CEECIND/01011/2018), through the individual scientific employment
program-contract, and L. Barros, through the institutional scientific
employment program-contract.info:eu-repo/semantics/publishedVersio
Proizvodnja ksilanaze uzgojem na čvrstoj podlozi s pomoću Aspergillus niger LPB 326 primjenom statističkog eksperimentalnog dizajna
Xylanase was produced by Aspergillus niger LPB 326 cultivated on lignocellulosic substrate composed by sugarcane bagasse and soybean meal in solid-state fermentation. The effects of various variables were observed and optimized by applying statistical experimental designs. The best xylanase activity was obtained in a medium containing 10 g of sugarcane bagasse and soybean meal in the ratio of 65 and 35 %, respectively, moistened to 85 % of initial water content with a nutrient salt solution composed of (in g/L): CuSO4 0.4, KH2PO4 1.5 and CoSO4 0.0012, and incubated for 4 days at 30 °C. Under these optimized conditions, a xylanase activity of 3099 IU/g of dry matter was obtained.U radu je istražena proizvodnja ksilanaze na lignoceluloznoj podlozi od otpadaka šećerne trske i sojine sačme s pomoću plijesni Aspergillus niger LPB 326. Ispitan je utjecaj različitih varijabli pa je proizvodnja optimirana primjenom statističkog eksperimentalnog dizajna. Najbolja aktivnost ksilanaze postignuta je upotrebom podloge s 10 g otpadaka šećerne trske i sojine sačme u omjeru 65:35, navlaženoj do 85 % početne vlažnosti otopinom hranjivih soli sastava (u g/L): CuSO4 0,4; KH2PO4 1,5 i CoSO4 0,0012; inkubiranoj tijekom 4 dana pri 30 °C. U tim uvjetima postignuta je aktivnost ksilanaze od 3099 IU/g suhe tvari
<b>Bioactive compounds from brewer’s spent grain: phenolic compounds, fatty acids and <i>in vitro</i> antioxidant capacity
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