UPLC-DAD-QToF/MS analysis of green tea phenolic metabolites in their free, esterified, glycosylated, and cell wall-bound forms by ultra-sonication, agitation, and conventional extraction techniques

Many current food and health trends demand the use of more ecological, sustainable, and environmentally friendly techniques for the extraction of bioactive compounds, including antioxidants. However, extraction yields and final antioxidant activities vary between sources and are highly influenced by the given extraction method and nature and ratio of the employed solvent, especially for total polyphenols, flavonoids, and anthocyanins, which are well recognized as natural antioxidants with food applications. This review focused on the most common extraction techniques and potential antioxidant activity in the food industry for various natural antioxidant sources, such as green tea, rosemary, clove, and oregano. Green extraction techniques have been proven to be far more efficient, environmentally friendly, and economical. In general, these techniques include the use of microwaves, ultrasound, high hydrostatic pressure, pulsed electric fields, enzymes, and deep eutectic solvents, among others. These extraction methods are described here, including their advantages, disadvantages, and applications.

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Extraction of Carotenoids from Pumpkin Peel and Pulp: Comparison between Innovative Green Extraction Technologies (Ultrasonic and Microwave-Assisted Extractions Using Corn Oil)

Foods ◽

10.3390/foods10040787 ◽

2021 ◽

Vol 10 (4) ◽

pp. 787

Author(s):

Minaxi Sharma ◽

Rajeev Bhat

Keyword(s):

Corn Oil ◽

Antioxidant Activities ◽

Food Product ◽

Extraction Techniques ◽

Protection Factor ◽

Total Carotenoids ◽

Green Extraction ◽

Microwave Assisted ◽

Potential Applications ◽

Conventional Extraction

Natural pigments improve aesthetic value as well as antioxidant potential of a food product. This study was designed to determine the effects of green extraction techniques on carotenoids, polyphenols and antioxidant activities of pulp and peel of two varieties of pumpkin (Cucurbita maxima). Innovative green extractions (IGE; Ultrasound and Microwave-Assisted Extractions) synergised with corn oil (used as green solvent) were compared with conventional extraction (CE; hexane/isopropyl alcohol; 60:40, v/v). Results showed total carotenoids to be almost double on employing IGE (PM2-UAE-peel = 38.03 ± 4.21; PM4-UAE-peel = 33.78 ± 1.76 µg/g) when compared to conventional extraction (PM2-CE-peel = 19.21 ± 4.39; PM4-CE-peel = 16.21 ± 2.52 µg/g). Polyphenolic contents ranged between 510.69 ± 5.50 and 588.68 ± 7.26 mg GAE/100 g of extract in IGE, compared with conventional extracts (269.50 ± 2.17 to 318.46 ± 6.60 mg GAE/100 g) and percent inhibition of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) ranging between 88.32 ± 1.51 and 93.53 ± 0.30% in IGE when compared with conventional extraction (50.61 ± 1.44 to 57.79 ± 2.09%). Further, oxidative stability of carotenoids extracts from IGE (protection factor = 1.59 ± 0.01 to 1.81 ± 0.05) were found to be significantly higher (p < 0.05) than conventional extracts. Based on results, this study supports the use of innovative green extraction techniques to obtain bioactive pigments like carotenoids. It is anticipated that results generated will find potential applications in food, pharmaceutical and cosmetic industries.

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Extraction Methods and Their Influence on Yield When Extracting Thermo-Vacuum-Modified Chestnut Wood

Forests ◽

10.3390/f12010073 ◽

2021 ◽

Vol 12 (1) ◽

pp. 73

Author(s):

Maurizio D’Auria ◽

Marisabel Mecca ◽

Maria Roberta Bruno ◽

Luigi Todaro

Keyword(s):

Catalyst Support ◽

Castanea Sativa ◽

Extraction Methods ◽

Extraction Technique ◽

Extraction Techniques ◽

Surface Color ◽

Ms Analysis ◽

Castanea Sativa Mill ◽

Molybdenum Catalysts ◽

Chestnut Wood

Improvements in the yield and solubility of chestnut wood extractives, by using different extraction methods and molybdenum catalysts as support, have rarely been reported in literature. Many studies focus on the different parts of trees, except for the chemical characteristics of the remaining extractives achieved from thermally modified (THM) chestnut (Castanea sativa Mill) wood. This research seeks to better understand the effects of extraction techniques and catalysts on the yield and solubility of extractives. GC-MS analysis of the chloroform soluble and insoluble fractions was also used. Accelerated Solvent Extraction (ASE) 110 °C, Soxhlet, and autoclave extraction techniques were used to obtain extractives from untreated and thermally modified (THM) chestnut wood (170 °C for 3 h). Ethanol/H2O, ethanol/toluene, and water were the solvents used for each technique. A polyoxometalate compound (H3PMo12O40) and MoO3 supported on silica were used as catalysts. The THM induced a change in the wood’s surface color (ΔE = 21.5) and an increase in mass loss (5.9%), while the equilibrium moisture content (EMC) was reduced by 17.4% compared to the control wood. The yields of the extractives and their solubility were always higher in THM and mainly used ASE as the technique. GC-MS analysis of the extractives, without catalyst support, showed different results for each extraction technique and type of wood (untreated and THM). Ultimately, the amount of extractive compound dissolved in each solvent will differ, and the choice of extraction technique will depend on the intended final application of the extracted chemical product.

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Anthocyanins Recovered from Agri-Food By-Products Using Innovative Processes: Trends, Challenges, and Perspectives for Their Application in Food Systems

Molecules ◽

10.3390/molecules26092632 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2632

Author(s):

Henrique Silvano Arruda ◽

Eric Keven Silva ◽

Nayara Macêdo Peixoto Araujo ◽

Gustavo Araujo Pereira ◽

Glaucia Maria Pastore ◽

...

Keyword(s):

Food Systems ◽

Food Industry ◽

Biological Properties ◽

Extraction Techniques ◽

Naturally Occurring ◽

Current Review ◽

Natural Colorants ◽

Conventional Extraction ◽

The Stability ◽

By Products

Anthocyanins are naturally occurring phytochemicals that have attracted growing interest from consumers and the food industry due to their multiple biological properties and technological applications. Nevertheless, conventional extraction techniques based on thermal technologies can compromise both the recovery and stability of anthocyanins, reducing their global yield and/or limiting their application in food systems. The current review provides an overview of the main innovative processes (e.g., pulsed electric field, microwave, and ultrasound) used to recover anthocyanins from agri-food waste/by-products and the mechanisms involved in anthocyanin extraction and their impacts on the stability of these compounds. Moreover, trends and perspectives of anthocyanins’ applications in food systems, such as antioxidants, natural colorants, preservatives, and active and smart packaging components, are addressed. Challenges behind anthocyanin implementation in food systems are displayed and potential solutions to overcome these drawbacks are proposed.

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Simultaneous Determination of Four Herbicide and Pesticide Residues in Chinese Green Tea Using QuEChERS Purification Procedure and UPLC-MS/MS Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1586 ◽

2013 ◽

Vol 634-638 ◽

pp. 1586-1590

Author(s):

Su Fang Wang ◽

Shou Jie Zhang ◽

Chun Hong Dong ◽

Guo Qing Wang ◽

Jun Feng Guo ◽

...

Keyword(s):

Formic Acid ◽

Simultaneous Determination ◽

Green Tea ◽

Limit Of Detection ◽

Multiple Reaction Monitoring ◽

Graphitized Carbon Black ◽

Ms Analysis ◽

Relative Standard ◽

Limit Of Quantitation

A method for simultaneous determination of residuals of four herbicides and pesticides, simazine, carboxin, diflubenzuron and rotenone, in Chinese green tea was developed. In the proposed method, the tea powder was placed in a centrifuge tube with a plug, extracted in saturated aqueous sodium chloride solution and acetonitrile, agitated using vortex oscillator, and then centrifuged 5 min at 4000 rpm. The supernatant solution was purified by primary secondary amine (PSA) sorbent, C18 power, and graphitized carbon black powder, respectively. Then the purified extracts were dissolved with acetonitrile:0.1% formic acid aqueous solution (40:60, V/V) and agitated, filtered using a syringe with 0.22 μm nylon filter prior to UPLC-MS/MS analysis. The UPLC analysis was performed on an ACQUITY UPLC® HSS T3 column (2.1 mm×100 mm, 1.8 µm), using acetonitrile-0.1% formic acid as mobile phase with the flow rate as 0.3 mL•min-1. Injection volume was 10 µL. Positive ionization mode was applied, and the ions were monitored in the multiple reaction monitoring (MRM) mode with curtain gas 0.069 MPa, collision gas 0.052 MPa, ESI ion spray voltage 5000 V, temperature 550 °C, nebulizer gas 0.24 MPa, and turbo gas 0.28 MPa. The limit of detection (LOD) and limit of quantitation (LOQ) of the proposed method are 1 μg•kg-1and 5 μg•kg-1, respectively. The average recoveries of the four pesticides at 10, 20, and 50 µg•kg-1spiking levels range from 77.4% to 95.3%. TheSupersSuperscript textcript textrelative standard deviation (RSD) (n=6) range form 11.83% to 4.52%.

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