Chemical composition and antioxidant activity of ultrasound-assisted extract of the endemic plant Haberlea rhodopensis Friv.

The investigation aimed to study the in vitro and in silico antioxidant properties of Melissa officinalis subsp. officinalis essential oil (MOEO). The chemical composition of MOEO was determined using GC–MS analysis. Among 36 compounds identified in MOEO, the main were beta-cubebene (27.66%), beta-caryophyllene (27.41%), alpha-cadinene (4.72%), caryophyllene oxide (4.09%), and alpha-cadinol (4.07%), respectively. In vitro antioxidant properties of MOEO have been studied in 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging, and inhibition of β-carotene bleaching assays. The half-maximal inhibitory concentration (IC50) for the radical scavenging abilities of ABTS and DPPH were 1.225 ± 0.011 μg/mL and 14.015 ± 0.027 μg/mL, respectively, demonstrating good antioxidant activity. Moreover, MOEO exhibited a strong inhibitory effect (94.031 ± 0.082%) in the β-carotene bleaching assay by neutralizing hydroperoxides, responsible for the oxidation of highly unsaturated β-carotene. Furthermore, molecular docking showed that the MOEO components could exert an in vitro antioxidant activity through xanthine oxidoreductase inhibition. The most active structures are minor MOEO components (approximately 6%), among which the highest affinity for the target protein belongs to carvacrol.

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Optimization of Ultrasound-Assisted Extraction of Phloretin and Other Phenolic Compounds from Apple Tree Leaves (Malus domestica Borkh.) and Comparison of Different Cultivars from Estonia

Antioxidants ◽

10.3390/antiox10020189 ◽

2021 ◽

Vol 10 (2) ◽

pp. 189

Author(s):

Sana Ben-Othman ◽

Hedi Kaldmäe ◽

Reelika Rätsep ◽

Uko Bleive ◽

Alar Aluvee ◽

...

Keyword(s):

Antioxidant Activity ◽

Apple Tree ◽

Maximum Yield ◽

Plant Secondary Metabolites ◽

Polyphenolic Compounds ◽

Tree Leaves ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Ultrasound Assisted ◽

Promising Source

Polyphenolic compounds, plant secondary metabolites essential for plant survival, are known for their high antioxidant and anti-inflammatory activity. In addition, several polyphenols, such as phloretin, also have potential antiviral effects, making these compounds potential ingredients of biofunctional foods. A promising source for the extraction of phloretin is a by-product of apple production—apple tree leaves. Focusing on green technologies, the first aim of the present study was to optimize the direct ultrasound-assisted extraction conditions to gain the maximum yield of phloretin from air-dried apple leaves. For the optimization of process parameters, we applied the response surface method with Box–Behnken design. The optimal extraction conditions were extraction time 14.4 min, sonication amplitude 10% and 10 g of sample per 100 mL solvent (70% ethanol, w/w). Using these conditions, we assessed the content of individual and total polyphenolic compounds along with antioxidant activity in the leaves of different autumn and winter apple cultivars grown in Estonia. The analyses were carried out with chromatographic (HPLC-DAD-MS/MS) and spectrophotometric methods. The phloretin concentration ranged from 292 to 726 µg/g and antioxidant activity from 6.06 to 11.42 mg GA eq./g, these being the highest in the local winter cultivars ‘Paide taliõun’ and ‘Tellissaare’, respectively.

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Homogenate-Ultrasound-Assisted Ionic Liquid Extraction of Total Flavonoids from Selaginella involven: Process Optimization, Composition Identification, and Antioxidant Activity

ACS Omega ◽

10.1021/acsomega.1c01087 ◽

2021 ◽

Author(s):

Jie Lei ◽

Lei Zhu ◽

Yu Zheng ◽

Ming Yu ◽

Gang Li ◽

...

Keyword(s):

Antioxidant Activity ◽

Ionic Liquid ◽

Process Optimization ◽

Liquid Extraction ◽

Total Flavonoids ◽

Ultrasound Assisted

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Comparative Assessment of the Basic Chemical Composition and Antioxidant Activity of Stevia rebaudiana Bertoni Dried Leaves, Grown in Poland, Paraguay and Brazil—Preliminary Results

Applied Sciences ◽

10.3390/app11083634 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3634

Author(s):

Teresa Leszczyńska ◽

Barbara Piekło ◽

Aneta Kopeć ◽

Benno F. Zimmermann

Keyword(s):

Antioxidant Activity ◽

Chemical Composition ◽

Vitamin C ◽

Dietary Fiber ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Stevia Rebaudiana ◽

Steviol Glycosides ◽

Total Polyphenols ◽

Stevia Rebaudiana Bertoni

This study compares the content of basic nutrients (proteins, fats, digestible carbohydrates, dietary fiber and ash), steviol glycosides, selected antioxidants (vitamin C, total polyphenols) and antioxidant activity in dried leaves of Stevia rebaudiana Bertoni cultivated in Poland, Paraguay and Brazil and available in the direct sale. The basic chemical composition was determined by standard AOAC (Association of Official Analytical Chemists) methods. Content of steviol glycosides was determined by the UHPLC-UV chromatographic method. Total polyphenols content was expressed as gallic acid equivalent (GAE) and catechins equivalent (CE). Antioxidant activity was measured as ABTS●+ free radical scavenging activity. Dried leaves of S. rebaudiana grown in Poland had significantly higher contents of dietary fiber, and lower protein and ash content, compared to those derived from Paraguay and Brazil. The former had, however, considerably higher contents of total steviol glycosides, stevioside and rebaudioside D, compared to the remaining two plants. In the Paraguay-derived dried leaves, the content of rebaudioside A, C, E and rubusoside was found to be significantly lower. Dried leaves of S. rebaudiana Bertoni, cultivated in Poland, contained substantially more vitamin C and a similar content of total polyphenols, compared to those from Brazil and Paraguay. The examined material from Brazil and Paraguay plantations showed similar antioxidant activity, while that obtained from Polish cultivation was characterized by a significantly lower value of this parameter.

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Effect of Ultrasound-Assisted Extraction Parameters on Total Polyphenols and Its Antioxidant Activity from Mango Residues (Mangifera indica L. var. Manililla)

Separations ◽

10.3390/separations8070094 ◽

2021 ◽

Vol 8 (7) ◽

pp. 94

Author(s):

Anahí J. Borrás-Enríquez ◽

Elizabeth Reyes-Ventura ◽

Socorro J. Villanueva-Rodríguez ◽

Lorena Moreno-Vilet

Keyword(s):

Antioxidant Activity ◽

Mangifera Indica ◽

Central Point ◽

Added Value ◽

Sonication Time ◽

Ultrasound Assisted Extraction ◽

Extraction Technology ◽

Total Polyphenols ◽

Assisted Extraction ◽

Ultrasound Assisted

Manililla is a mango variety whose residues contain bioactive compounds such as polyphenols and flavonoids, with high added value. The use of environmentally friendly extraction technology would be of great relevance; hence, this study aimed to evaluate the effect of solvent relation, sonication time and amplitude on the ultrasound-assisted extraction of total polyphenols in Manililla mango residues (peel, endocarp and kernel) and antioxidant activity. An experimental design 23 with a central point was used to evaluate the curvature behavior of the process variables. Conventional maceration was used as a control. The better conditions were obtained at the central point using 50% ethanol in water, 60% amplitude and 20 min of sonication time. We obtained values of up to 1814 mg GAE/100 g, 469 mg GAE/100 g and 672 mg GAE/100 g of total polyphenols and 1228 mg QE/100 g, 653 mg QE/100 g and 880 mg QE/100 g of total flavonoids for peel, endocarp and kernel, respectively. Mangiferin was quantified in ultrasound-assisted extraction at 150 mg/g in peel and 0.025 mg/g in the kernel, but it was not detectable in maceration. An antioxidant capacity of 87%, 14% and 83% inhibition for peel, endocarp and kernel, respectively, were obtained. Peel and kernel were the residues with higher potential as extraction material, while endocarp was not.

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Ripening Changes of the Chemical Composition, Proteolysis, and Lipolysis of a Hair Sheep Milk Mexican Manchego-Style Cheese: Effect of Nano-Emulsified Curcumin

Foods ◽

10.3390/foods10071579 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1579

Author(s):

Mariam Sardiñas-Valdés ◽

Hugo Sergio García-Galindo ◽

Alfonso Juventino Chay-Canul ◽

José Rodolfo Velázquez-Martínez ◽

Josafat Alberto Hernández-Becerra ◽

...

Keyword(s):

Principal Component Analysis ◽

Antioxidant Activity ◽

Chemical Composition ◽

Phenolic Content ◽

Principal Component ◽

Total Phenolic ◽

Hair Sheep ◽

Dairy Foods ◽

Ripening Time ◽

Sheep Milk

The influence of nano-emulsified curcumin (NEC) added to the hair sheep milk, prior to cheese-making, on the chemical composition, lipolysis, and proteolysis of manchego-style cheeses were evaluated throughout 80 days of ripening. The addition of NEC to the milk resulted in cheeses with the same moisture content (42.23%), total protein (23.16%), and water activity (0.969) (p > 0.05). However, it increased the fat and ash levels from 26.82% and 3.64% in B 10 ppm to 30.08% and 3.85% in C 10 ppm, respectively, at the end of the ripening (p < 0.05). The total phenolic content and antioxidant activity of experimental cheeses increased during ripening, and the fatty acid groups showed significant changes occurred to a greater extent in the first days of ripening (p < 0.05). The lipolysis increased consistently in all cheeses until day 40 of ripening, to decrease at the end, while proteolysis increased during all ripening time in all samples (p < 0.05); the addition of NEC did not alter the primary proteolysis of manchego-style cheeses, but it modified secondary proteolysis and lipolysis (p < 0.05). Principal component analysis was useful for discriminating cheeses according to their chemical composition and classified into four groups according to their ripening time. This research highlights the potential of CNE to fortify dairy foods to enhance their functionality.

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