scholarly journals Microwave heating effect on total phenolics and antioxidant activity of green and mature coconut water

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Abraham Jesús Arzeta-Ríos ◽  
Diana Guerra-Ramírez ◽  
Benito Reyes-Trejo ◽  
Ma. Carmen Ybarra-Moncada ◽  
Holber Zuleta-Prada

AbstractCoconut water (Cocos nucifera L.) from fruits of two ripening stages (green and mature) was used to perform microwave heat treatments. Three different heating conditions with maximum temperatures of 70, 80 and 90 °C were tested in three holding times (0, 2 and 4 min). The Total Phenolic Content (TPC) using the Folin-Ciocalteu method and ABTS radical scavenging capacity were evaluated for each combination of coconut fruit age, heating temperature and holding time. It was observed that green coconut water exhibited significant differences (p < 0.05) compared to mature coconuts in terms of TPC (46.03 and 69.16 mg GAE/L, respectively) and ABTS radical scavenging capacity (422.31 and 549.1 μmol TE/L, respectively). An increase in TPC (up to 23%) and antioxidant activity (up to 19%) was also observed with increasing temperature in the range of 70–90 °C. Green coconut water showed the largest increase in both TPC and antioxidant activity.

2012 ◽  
Vol 7 (2) ◽  
pp. 1934578X1200700 ◽  
Author(s):  
Laura Giamperi ◽  
Anahi Bucchini ◽  
Angela Bisio ◽  
Emanuela Giacomelli ◽  
Giovanni Romussi ◽  
...  

The total phenolic content and antioxidant activity of 6 Salvia spp. exudates were measured to find new potential sources of natural antioxidants. Total phenolic content was assessed by a modified Prussian blue method, and the antioxidant activity by two methods: 1,1- diphenyl-2-picryl- hydrazyl (DPPH) radical scavenging capacity assay and lipoxygenase inhibitory assay. The total phenolic content ranged between 1.3 μg/mg DW ( S. fallax) and 74.0 μg/mg DW ( S. cacaliaefolia). In the DPPH test, S. cacaliaefolia was more effective than BHT, while in the inhibition of lipid peroxidation all the extracts presented good antioxidant capacity.


Author(s):  
Devi Rajeswari

ABSTRACTObjective: The present study was aimed to examine the in vitro antioxidant property and free radical scavenging capacity of Punica granatum leaves, which are widely used in the Ayurvedic treatment.Methods: Aqueous and methanol extracts were prepared and to assess for their Phytochemical analysis to find out the various compounds and total yield of phenolic and flavonoid contents by spectrophotometer methods. Free-radical scavenging capacity and antioxidant activity was estimated by using a number of chemical assays are DPPH, H2O2, FRAP, TRAP and beta carotene assay.Results: It showed that aqueous extract had greatest antioxidant activity and contained significant levels of total phenolic and flavonoids content expressed as mg of gallic acid and quercetin equivalent/g of extracts. The extracts showed antioxidant activity in vivo by protecting yeast cells against oxidative stressing agent H2O2. Conclusion: These results specified the Punica granatum is good source of natural compounds which might have benefits for health, which can be used in dietary application with a possible to reduce oxidative stress.Key words:  Punica granatum, Free-radical scavenging capacity, phytochemical, antioxidant, yeast culture.


2019 ◽  
Vol 11 (1) ◽  
pp. 35-43 ◽  
Author(s):  
Luciana Carolina Bauer ◽  
Ellen Cristina Quirino Lacerda ◽  
Leandro Soares Santos ◽  
Sibelli Passini Barbosa Ferrão ◽  
Rafael da Costa Ilhéu Fontan ◽  
...  

Background:The investigation of new sources of raw materials and the knowledge of the composition of the food is fundamental for the evaluation of their potential and the availability of nutrients for the consumer population.Objective:This work aimed to deepen the knowledge about the crude oil of babassu fruit obtained by two different methods of extraction, cold pressing and extraction by cooking the fruit almond.Method:Total phenolic compounds contents and antioxidant activity were determined by ferric reducing antioxidant potential assay and 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity assay. By liquid chromatography, the content of different bioactive compounds was determined. Data was submitted to Analysis of Variance (ANOVA) and compared by f test (p <0.05).Results:The results showed that for most of the bioactive compounds there was no difference between the two types of babassu oil. For those compounds where the oils differed, the virgin oil had about three times the content of the extra-virgin oil. In addition, the antioxidant activity was higher for the oil extracted by cooking of the babassu mass, ranging from approximately 2.5 times higher up to 19.2 times higher than the antioxidant activity of the babassu oil extracted by pressing.Conclusion:The process of extraction by cooking the almond mass can incorporate a larger number of bioactive components and improve the antioxidant activity of the virgin babassu oil. However, the extraction method does not influence the content of tocopherols of distinct types of babassu oil.


Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5265
Author(s):  
Concepción Pérez-Lamela ◽  
Inmaculada Franco ◽  
Elena Falqué

Fruits and fruit products are an essential part of the human diet. Their health benefits are directly related to their content of valuable bioactive compounds, such as polyphenols, anthocyanins, or vitamins. Heat treatments allow the production of stable and safe products; however, their sensory quality and chemical composition are subject to significant negative changes. The use of emerging non-thermal technologies, such as HPP (High Pressure Processing), has the potential to inactivate the microbial load while exerting minimal effects on the nutritional and organoleptic properties of food products. HPP is an adequate alternative to heat treatments and simultaneously achieves the purposes of preservation and maintenance of freshness characteristics and health benefits of the final products. However, compounds responsible for antioxidant activity can be significantly affected during treatment and storage of HPP-processed products. Therefore, this article reviews the effect of HPP treatment and subsequent storage on the antioxidant activity (oxygen radical absorbance capacity (ORAC) assay), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay, ferric reducing antioxidant power (FRAP) assay, 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity assay or Trolox equivalent antioxidant capacity (TEAC) assay), and on the total phenolic, flavonoid, carotenoid, anthocyanin and vitamin contents of fruits and different processed fruit-based products.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 712
Author(s):  
Tafadzwa Kaseke ◽  
Umezuruike Linus Opara ◽  
Olaniyi Amos Fawole

The present research studied the influence of blanching and microwave pretreatment of seeds on the quality of pomegranate seed oil (PSO) extracted by cold pressing. Pomegranate seeds (cv. Acco) were independently blanched (95 ± 2 °C/3 min) and microwave heated (261 W/102 s) before cold pressing. The quality of the extracted oil was evaluated with respect to oxidation indices, refractive index, yellowness index, total carotenoids content, total phenolic content, flavor compounds, fatty acid composition, and 2.2-diphenyl-1-picryl hydrazyl (DPPH) and 2.2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging capacity. Blanching and microwave pretreatments of seeds before pressing enhanced oil yield, total phenolic content, flavor compounds, and DPPH and ABTS radical scavenging capacity. Although the levels of oxidation indices, including the peroxide value, free fatty acids, acid value, ρ-anisidine value, and total oxidation value, also increased, and the oil quality conformed to the requirements of the Codex Alimentarius Commission (CODEX STAN 19-1981) standard for cold-pressed vegetable oils. On the other hand, blanching and microwave heating of seeds decreased the pomegranate seed oil’s yellowness index, whilst the refractive index was not significantly (p > 0.05) affected. Even though both blanching and microwave pretreatment of seeds added value to the cold-pressed PSO, the oil extracted from blanched seeds exhibited lower oxidation indices. Regarding fatty acids, microwave pretreatment of seeds before cold pressing significantly increased palmitic acid, oleic acid, and linoleic acid, whilst it decreased the level of punicic acid. On the contrary, blanching of seeds did not significantly affect the fatty acid composition of PSO, indicating that the nutritional quality of the oil was not significantly affected. Therefore, blanching of seeds is an appropriate and valuable step that could be incorporated into the mechanical processing of PSO.


2012 ◽  
Vol 554-556 ◽  
pp. 1357-1360
Author(s):  
Zhong Li Jiang ◽  
Ai Li Wang ◽  
Xi Hong Li ◽  
Min Peng Zhu ◽  
Jun Wei Wang

The present study investigated the effect of 1-MCP on bioavailability of Lingwu long jujube stored at 0 °C for 60 days. At the end of the storage, compared with the control samples, Lingwu long jujube treated with 1-MCP exhibited higher Vc bioaccessibility, total phenolic content and free radical scavenging capacity, which demonstrated that 1-MCP treatment could provide a better effect on maintaining the bioavailability of Lingwu long jujube.


Molecules ◽  
2018 ◽  
Vol 23 (10) ◽  
pp. 2655 ◽  
Author(s):  
Yolanda Moreno-Ramírez ◽  
Guillermo Martínez-Ávila ◽  
Víctor González-Hernández ◽  
Cecilia Castro-López ◽  
Jorge Torres-Castillo

The total phenolic compounds content, free radical-scavenging capacity and capsaicinoid content in populations of wild Piquin chili (C. annuum) were studied. Aqueous and hydroalcoholic extracts from nine ecotypes were evaluated. High contents of phenolic compounds and free radical-scavenging capacities were observed for both extracts; however, the values that were found for the hydroalcoholic phase were substantially higher. LC-MS analysis allowed for the detection of 32 compounds, where apigenin-8-C-glucoside followed by vanillic acid 1-O-β-o-glucopyranosylester (Isomer I or II) and 7-ethoxy-4-methylcoumarin were the most widely distributed; they were found in more than 89% of the ecotypes. The diversity of identified phenolic compounds was different among ecotypes, allowing them to be distinguished by chemical diversity, free radical-scavenging capacities and heat Scoville units. The total capsaicinoid content was higher in Population I (23.5 mg/g DW) than in Populations II and III, which had contents of 15.3 and 10.7 mg/g DW, respectively. This variability could lead to phytochemical exploitation and the conservation of the natural populations of wild chili.


Author(s):  
L Azeez

This study examined the influence of microbial contamination on the antioxidant composition and free radical scavenging effects of fresh and decaying spices: Lycopersicon esculentum, Capsicum frutescens S, Capsicum frutescens T and Capsicum annum used by food vendors. Microbial load was enumerated with potato dextrose agar (PDA) using the pour plate technique, phytochemical components were determined using Folio-Ciocalteu, Aluminium chloride, acetone-hexane methods for phenolic, flavonoids and β-carotene & lycopene respectively while free radical scavenging capacity was determined using DPPH method. Decaying L. esculentum had highest microbial population of 7.14 X 105 cfu/g and fresh C. annum had the lowest microbial population of 0.72 X 101cfu/g. Microbial population in decaying spices were generally significantly higher than fresh spices. Aspergillus spp were found in all decaying spices and in fresh C. frutescens T. Microsporum spp were found in all fresh spices except in C. frutescens T and in decaying spices except in C. annum. There were significant decreases (p <0.05) in phenolic, flavonoid, β-carotene and free radical scavenging capacity contents of all decaying spices compared to fresh spices except for phenolic content in C. annum while significant decrease (p < 0.05) in lycopene content was obtained for only decaying L. esculentum compared to fresh one. Reduction in antioxidant activity and phytochemical contents could not be unconnected with the high microbial population in decaying spices because antioxidant activity and phytochemical contents significantly correlate with antibacterial activity. Thus, consumption of decaying spices as shown by our study could pose a serious health challenges due to the presence of high number of microbes detected and loss of healthprotecting ability of the spices. Â


2017 ◽  
Vol 12 (3) ◽  
pp. 1934578X1701200 ◽  
Author(s):  
Eleni Kollia ◽  
Panagiota Markaki ◽  
Panagiotis Zoumpoulakis ◽  
Charalampos Proestos

Extracts and infusions of wild artichoke ( Cynara cardunculus L.) and globe artichoke ( C. scolymus L.) (heads, bracts and stems) were examined for their total phenolic content (TPC) and their antioxidant activity after performing Classical Extraction (CE) and Ultrasound-Assisted Extraction (UAE). UAE proved to be more effective, since extracts exhibited higher antioxidant activity and TPC values than CE extracts and infusions. Moreover C. cardunculus heads extract using UAE, displayed the maximum TPC values (1.57 mg gallic acid equivalents (GAE) g−1 fresh weight (fw)), the highest DPPH• scavenging activity (IC50; 0.91mg mL−1) and the highest ABTS•+ radical scavenging capacity (2.08 mg Trolox Equivalents (TE) g−1 fw). Moreover, the effect of different concentrations of C. cardunculus head extracts (showing the highest TPC and antioxidant activity) on Aspergillus parasiticus growth was estimated in AFPA medium. The maximum inhibition was found to be ~42.1% in comparison with the control.


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