scholarly journals Stability of Phenolic Compounds in Grape Stem Extracts

Antioxidants ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 720
Author(s):  
Irene Esparza ◽  
María José Cimminelli ◽  
Jose Antonio Moler ◽  
Nerea Jiménez-Moreno ◽  
Carmen Ancín-Azpilicueta

Grape stem is rich in phenolic compounds, especially stilbenes. These antioxidants can be degraded during the storage of grape stem extracts for long periods of time. The aim of this work was to analyze the stability of Mazuelo stem extracts during storage at 25 and 40 °C, in two different light conditions (amber and transparent vials). The stability of the antioxidants was studied after 2, 4 and 6 months of conservation. Gallic acid and the quercetin derivative concentration were stable throughout the storage period. In contrast, catechin disappeared from all the extracts in just two months of storage. Anthocyanins were significantly affected by temperature, and light enhanced their degradation when the extracts were kept at 40 °C. Resveratrol and viniferin showed a similar behavior. Their concentration decreased from the beginning of storage, and in both cases, they were significantly affected by both temperature and light.

Author(s):  
ANA PAULA DE CARVALHO ALVES ◽  
ANGELITA DUARTE CORRÊA ◽  
JÉSSICA BORELI DOS REIS LINO ◽  
TAMARA REZENDE MARQUES

The stability of jaboticaba skin fl our was evaluated during 12months of storage, for the purpose of extending the use of this fl ourthroughout the year, because jaboticaba production is seasonal.Ripe Plinia jaboticaba (Vell.) Berg fruits, of the Sabará genotype,were collected and the separated skins were dried at a temperatureof 45 oC. They were then ground and stored in hermetically sealedfl asks and protected from light at room temperature for 0, 3, 6, 9 and12 months. At each storage time, analyses of proximate composition,vitamin C, phenolic compounds, anthocyanins, soluble solids, wateractivity, color, pH and microbiological analysis were conducted.It was possible to observe a signifi cant increase in the followingparameters during the 12 months of storage: humidity, 34 %; wateractivity, 31.23 %; a color coordinates,12.37 % and b colorcoordinates, 24 %; pH, 7.35 %. There was a decrease in phenoliccontent of 9.91 %; anthocyanins 29 % and vitamin C 20 %. Therewas no signifi cant difference in the levels of lipids, protein, ash, fi berand soluble solids, and the presence of microorganisms was notdetected for any storage period. Therefore, it is possible to concludethat the jaboticaba skin fl our did not show signifi cant changes innutritional parameters, and showed a small reduction in antioxidantcompounds when stored for periods up to 12 months. This fl our cantherefore be considered as an alternative for the enrichment of foodproducts throughout the year


2021 ◽  
Vol 8 (1) ◽  
pp. 9
Author(s):  
Laura Brelle ◽  
Estelle Renard ◽  
Valerie Langlois

A novel generation of gels based on medium chain length poly(3-hydroxyalkanoate)s, mcl-PHAs, were developed by using ionic interactions. First, water soluble mcl-PHAs containing sulfonate groups were obtained by thiol-ene reaction in the presence of sodium-3-mercapto-1-ethanesulfonate. Anionic PHAs were physically crosslinked by divalent inorganic cations Ca2+, Ba2+, Mg2+ or by ammonium derivatives of gallic acid GA-N(CH3)3+ or tannic acid TA-N(CH3)3+. The ammonium derivatives were designed through the chemical modification of gallic acid GA or tannic acid TA with glycidyl trimethyl ammonium chloride (GTMA). The results clearly demonstrated that the formation of the networks depends on the nature of the cations. A low viscoelastic network having an elastic around 40 Pa is formed in the presence of Ca2+. Although the gel formation is not possible in the presence of GA-N(CH3)3+, the mechanical properties increased in the presence of TA-N(CH3)3+ with an elastic modulus G’ around 4200 Pa. The PHOSO3−/TA-N(CH3)3+ gels having antioxidant activity, due to the presence of tannic acid, remained stable for at least 5 months. Thus, the stability of these novel networks based on PHA encourage their use in the development of active biomaterials.


Author(s):  
Razieh Niazmand ◽  
Samira Yeganehzad

Abstract Background Barberry has long been used as an herbal remedy since ancient times which is found throughout temperate and subtropical regions of the world. Given the short harvesting season and limited shelf life of the barberry, we evaluated the possibility of using modified atmosphere packaging and oxygen-scavenger sachets to increase its storage period. For this purpose, the physicochemical characterization (antioxidant activity, anthocyanin, phenolic compounds, and ascorbic acid content, acidity, firmness, color, and decay incident) of fresh barberry samples packaged within different atmospheres was investigated over 4 weeks of storage at 4 and 25 °C. The barberries were packaged with low-density polyethylene/polyester (LDPE/PET) films under natural atmosphere (C), N2 gas (N), vacuum (V), or in the presence of an oxygen scavenger (OS). Results The results revealed that with increased storage period, the O2 and CO2 levels inside the packages decreased and increased, respectively. The antioxidant activity and amounts of anthocyanin, phenolic compounds, and ascorbic acid all decreased with increasing storage period. Among the studied atmospheres, the OS and, subsequently, V packages were most capable of maintaining the quality of fresh barberries, with the decay incidence being approximately 30 times lower inside these packages relative to the control. Increasing the storage temperature accelerated the intensity of chemical changes and decay across all samples. Conclusion The barberries inside the OS packages stored at 4 °C (and even at 25 °C) still had good sensory properties in terms of chemical properties, texture, and color after 4 weeks. Fortunately, it seems that this packaging technology makes the exportation and delayed consumption of the fresh barberry possible by maintaining its quality.


Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 152
Author(s):  
Xin Wang ◽  
Qingjun Zhu ◽  
Xiangju Liu ◽  
Baorong Hou

This work studied the application of phosphoric acid-gallic acid in vinyl chloride acrylic emulsion and its rust conversion performance. The increase of phosphoric acid affected the stability of the system, leading to the rapid precipitation of flocculent precipitation. Rust conversion coating (RCC) showed the best synergistic conversion effect when gallic acid (GA) was 0.2 wt.% and phosphoric acid (PA) was 2 wt.%. XRD and FTIR analysis show that the components of adherent rust (AR) are α-FeOOH, γ-FeOOH and Fe3O4. The conversion products are ferric phosphate (FP) and ferric gallate (FG). The RCC can effectively treat the rusted steel (RS) produced by simulated marine atmospheric corrosion. The corrosion current density was reduced by three orders of magnitude, the adhesion reached 2.75 MPa, and the salt spray corrosion resistance was 20 days. The results of Raman, XPS, SEM and EDS show that the ionic dissolution of iron, complexation and further oxidation reactions occur at the interface between the adherent rust and the RCC. After rust conversion treatment, unreacted rust (UR) affects the further improvement of adhesion strength and anti-corrosion performance.


Author(s):  
А.Л. Майтаков ◽  
Л.Н. Берязева ◽  
Н.Т. Ветрова ◽  
К.Б. Плотников

Разработан новый быстрорастворимый продукт (кисель) с определенным фазовым составом и строением на основе молочной сыворотки и местного растительного сырья – черноплодной рябины (Aronia melanocarpa). Разработана модель технологии производства быстрорастворимого гранулированного продукта (кисель) на основе молочной сыворотки и черноплодной рябины. Исследована сохраняемость киселя в трех температурных режимах: 1-й (21 ± 1)°С; 2-й с низкой плюсовой температурой (5 ± 1)°С; 3-й с повышенной (39 ± 1)°С при влажности окружающей среды 80%. По окончании годичного исследования сохраняемости при температурных режимах (21 ± 1)°С и (5 ± 1)°С изменений в органолептических показателях продукта не наблюдали. Скорость растворения продукта при температурных условиях хранения (21 ± 1)°С и (5 ± 1)°С не изменялась на протяжении 9 мес. Установлено, что при хранении в условиях пониженных положительных температур 4–6°С и в режиме комнатной температуры (21 ± 1)°С исследуемый пищеконцентрат по окончании 6 мес. хранения не изменил свойств по показателям качества. Сроки испытания продукта превышали по длительности в 2 раза заданный срок хранения (коэффициент запаса). Результаты испытаний явились основанием для разработки технической документации на производство быстрорастворимых гранулированных плодово-ягодных киселей. A new fast – soluble product (kissel) with a certain phase composition and structure based on whey and local plant raw materials Aronia melanocarpa. A model of technology for the production of a rapidly soluble granular product (kissel) based on whey and Aronia melanocarpa has been developed. The stability of kissel in three temperature modes was studied: 1st (21 ± 1)°C; 2nd with a low plus temperature (5 ± 1)°C; the 3rd with the increased (39 ± 1)°C at 80% ambient humidity. At the end of a year-long study at temperature conditions (21 ± 1)°С and (5 ± 1)°С, no changes in the organoleptic characteristics of the product were observed. Dissolution rate of the product under storage temperature conditions (21 ± 1)°C and (5 ± 1)°C did not change for 9 months. It is established that when stored at low positive temperatures 4–6°C. With and at room temperature (21 ± 1)°C. At the end of 6 months of storage, the food concentrate under study did not change its properties in terms of quality. The product testing period was 2 times longer than the specified storage period. The test results were the basis for the development of technical documentation for the production of instant granulated fruit and berry kissel.


2021 ◽  
pp. 34-37
Author(s):  
Екатерина Владимировна Ульянова ◽  
Дарья Владиславовна Андриевская

Стабильность (розливостойкость) в течение длительного времени - одна из важных составляющих качественных характеристик спиртных напитков виноградного происхождения, в том числе коньяков. Коньяк представляет собой сложную многокомпонентную систему, включающую более 800 различных соединений, в том числе фенольный комплекс древесины дуба и минеральные вещества. В процессе длительного хранения под воздействием ряда факторов эти соединения, вступая во взаимодействие друг с другом, могут образовывать различные виды помутнений, что влечет за собой потерю товарного вида готовой продукции. Целью настоящей работы стало исследование влияния отдельных показателей физико-химического состава обработанных коньяков на изменение их стабильности в процессе хранения. В качестве объектов исследования использовали образцы обработанных розливостойких коньяков отечественного производства, которые были разделены в зависимости от возраста на четыре группы: I группа - 3-летние, 4-летние и 5-летние (23 образца); II группа - выдержанные «КВ» и выдержанные высшего качества «КВВК» (15 образцов); III группа - старые «КС» (9 образцов); IV группа - очень старые «ОС» (7 образцов). Образцы хранили в течение 6 мес. при температуре 22…25 °С, в условиях, не допускающих попадания прямых солнечных лучей. В процессе хранения проводили мониторинг изменения физико-химических показателей, розливостойкости и органолептических характеристик исследуемых образцов с периодичностью 1 раз в месяц. Установлено, что на всем протяжении хранения физико-химические показатели исследованных образцов оставались в пределах нормы. Однако, в отдельных образцах, на определенном этапе эксперимента (после 2 мес. хранения) было отмечено появление осадка. Кроме того, по результатам определения склонности к различным видам помутнений был отмечен рост доли коньяков, нестойких к необратимым коллоидным и кристаллическим помутнениям в трех группах, кроме IV группы. Полученные данные по исследованию структуры осадков и результаты тестов на розливостойкость согласуются с характером изменений массовых концентраций катионов натрия и кальция, а также фенольных соединений. В целом полученные результаты проведенных исследований показали необходимость контроля массовой концентрации катионов натрия и кальция, а также фенольных соединений при прогнозировании розливостойкости коньяков. One of the important components of the quality characteristics of alcoholic beverages of grape origin, including cognacs, is their stability (bottling resistance) for a long time. Cognac is a complex multicomponent system that includes more than 800 different compounds, including the phenolic complex of oak wood and minerals. During long-term storage, under the influence of a number of factors, these compounds, interacting with each other, can form various types of turbidity, which entails the loss of the presentation of the finished product. The aim of this work was to study the effect of individual indicators of the physical and chemical composition of processed cognacs on the change in their stability during storage. As objects of research, we used samples of processed bottling-resistant cognacs of domestic production, which were divided, depending on age, into four groups: Group I - three-year-old, four-year-old and five-year-old (23 samples); Group II - matured «KV» and matured of the highest quality «KVVK» (15 samples); Group III - old «KS» (9 samples); IV group - very old «OS» (7 samples). The samples were stored for 6 months at a temperature of 22…25 °C, in conditions out of direct sunlight. During storage, changes in physical and chemical parameters, bottling resistance and organoleptic characteristics of the samples under study were monitored at a frequency of 1 time per month. It was found that during the entire storage period, the physicochemical indicators of the studied samples remained within the normal range. However, in some samples, at a certain stage of the experiment (after 2 months of storage), the appearance of a precipitate was noted. In addition, according to the results of determining the tendency to various types of cloudiness, an increase in the proportion of cognacs unstable to irreversible colloidal and crystalline cloudiness was noted in three groups, except for group IV. The data obtained on the study of the structure of sediments and the results of tests for pouring resistance are consistent with the nature of changes in the mass concentrations of sodium and calcium cations, as well as phenolic compounds. In general, the results of the studies carried out showed the need to control the mass concentration of sodium and calcium cations, as well as phenolic compounds when predicting the pouring resistance of cognacs.


2019 ◽  
Vol 79 (3) ◽  
pp. 452-459 ◽  
Author(s):  
F. R. G. Silva ◽  
T. M. S. Matias ◽  
L. I. O. Souza ◽  
T. J. Matos-Rocha ◽  
S. A. Fonseca ◽  
...  

Abstract The study aimed to evaluate the antimicrobial activity, antioxidant, toxicity and phytochemical screening of the Red Propolis Alagoas. Antimicrobial activity was evaluated by disk diffusion method. Determination of antioxidant activity was performed using the DPPH assay (1.1-diphenyl-2-picrylhydrazyl), FTC (ferric thiocyanate) and determination of phenolic compounds by Follin method. Toxicity was performed by the method of Artemia salina and cytotoxicity by MTT method. The phytochemical screening for the detection of allelochemicals was performed. The ethanol extract of propolis of Alagoas showed significant results for antimicrobial activity, and inhibitory activity for Staphylococcus aureus and Candida krusei. The antioxidant activity of the FTC method was 80% to 108.3% hydrogen peroxide kidnapping, the DPPH method showed an EC50 3.97 mg/mL, the content of total phenolic compounds was determined by calibration curve gallic acid, resulting from 0.0005 mg/100 g of gallic acid equivalent. The extract was non-toxic by A. salina method. The propolis extract showed high activity with a higher percentage than 75% inhibition of tumor cells OVCAR-8, SF-295 and HCT116. Chemical constituents were observed as flavonones, xanthones, flavonols, and Chalcones Auronas, Catechins and leucoanthocyanidins. It is concluded that the extract can be tested is considered a potential source of bioactive metabolites.


2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Janet Alejandra Espejel-Nava ◽  
Elisa Vega-Avila ◽  
Francisco Alarcon-Aguilar ◽  
Alejandra Contreras-Ramos ◽  
Guadalupe Díaz-Rosas ◽  
...  

Catharanthus roseus (L.) G. (C. roseus) is a medicinal plant used traditionally for diabetes mellitus control. Several compounds of an alkaloidal nature have been proposed as hypoglycemic principles. However, little attention has been paid to other compounds in this plant that could also participate in this hypoglycemic activity. This study aimed to analyze the hypoglycemic effect of a polyphenolic fraction from C. roseus, as well as its action on insulin secretion and expression in RINm5F cells. Methods. An alkaloid-free aqueous extract was obtained from C. roseus stems. The hypoglycemic effect of different doses of this extract was evaluated in normal and streptozotocin-induced diabetic mice. This extract was fractionated by bipartition, and the resultant fractions were assessed by their hypoglycemic effects. Subsequently, the fraction with the greater hypoglycemic activity was added to the RINm5F cells, and the expression and secretion of insulin were analyzed. The antioxidant activity was determined by the DPPH method and through chromatographic analysis of the most active fraction by HPLC, using an Econosphere C18 column. Results. The aqueous alkaloid-free extract of C. roseus stems significantly reduced blood glucose in normal and diabetic mice. The fractionation of this extract provided three fractions, one of which (a precipitate) showed significant reductions in glycemia at 6 h (48.1 and 64.5% in normal and diabetic mice, respectively). This precipitate contained phenolic compounds and saponins. Its chromatographic analysis showed that it is formed by several phenolic compounds; gallic acid (0.053%) and chlorogenic acid (0.216%) were identified and quantified. Conclusion. The phenolic fraction of C. roseus containing gallic acid and chlorogenic acid had a hypoglycemic effect that may be explained by an increase in insulin secretion.


Author(s):  
Ruben Ashotovich Pogosyan ◽  
Olga Vladimirovna Nesterova ◽  
Dmitry Olegovich Bokov ◽  
Irina Alexandrovna Samylina

Objective: Pomegranate (Punica granatum L.) is a broadly used plant possessing a wide range of medicinal properties. In this research, we have mainly focused on the investigation of phenolic compounds of pomegranate fruit pulp (PFP).Methods: Fresh fruits of “Çəhrayı Gülöyşə,” “Kizil-anor,” and pomegranate varietal mixture were used as samples. High-performance liquid chromatography-ultraviolet (HPLC-UV) analysis of phenol carboxylic acids was performed with metal column Kromasil® C18 (4.6×250 mm, particle size 5 μm) and the acetonitrile-water-concentrated acid phosphoric system (400:600:5) under isocratic elution conditions (flow rate of 0.5 ml/min). Detection was carried out using a UV detector “GILSTON” UV/Visible model 151 at a wavelength of 280 nm.Results and Discussion: As a result of our research, we proposed chromatographic conditions for the separation of phenolic compounds, the conditions for sample preparation of PFP. Procedure for determination of phenolic carboxylic acids total content in terms of gallic acid by HPLC-UV method was developed. According to the obtained data, the content of phenolic carboxylic acids should be at least 0.7%.Conclusion: Procedure for the quantitative determination of gallic acid using the HPLC-UV method was developed. This method which can be used in the standardization of new medicinal plant raw materials - PFP, as well as extract preparations based on it in the future.


Author(s):  
Ruben Ashotovich Pogosyan ◽  
Olga Vladimirovna Nesterova ◽  
Dmitry Olegovich Bokov ◽  
Irina Alexandrovna Samylina

Objective: Pomegranate (Punica granatum L.) is a broadly used plant possessing a wide range of medicinal properties. In this research, we have mainly focused on the investigation of phenolic compounds of pomegranate fruit pulp (PFP).Methods: Fresh fruits of “Çəhrayı Gülöyşə,” “Kizil-anor,” and pomegranate varietal mixture were used as samples. High-performance liquid chromatography-ultraviolet (HPLC-UV) analysis of phenol carboxylic acids was performed with metal column Kromasil® C18 (4.6×250 mm, particle size 5 μm) and the acetonitrile-water-concentrated acid phosphoric system (400:600:5) under isocratic elution conditions (flow rate of 0.5 ml/min). Detection was carried out using a UV detector “GILSTON” UV/Visible model 151 at a wavelength of 280 nm.Results and Discussion: As a result of our research, we proposed chromatographic conditions for the separation of phenolic compounds, the conditions for sample preparation of PFP. Procedure for determination of phenolic carboxylic acids total content in terms of gallic acid by HPLC-UV method was developed. According to the obtained data, the content of phenolic carboxylic acids should be at least 0.7%.Conclusion: Procedure for the quantitative determination of gallic acid using the HPLC-UV method was developed. This method which can be used in the standardization of new medicinal plant raw materials - PFP, as well as extract preparations based on it in the future.


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