scholarly journals Processing of Herbal Tea from Roselle (Hibiscus sabdariffa L.): Effects of Drying Temperature and Brewing Conditions on Total Soluble Solid, Phenolic Content, Antioxidant Capacity and Sensory Quality

Beverages ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 2
Author(s):  
Quang Vinh Nguyen ◽  
Hoang Van Chuyen
Keyword(s):  
Antioxidant Capacity ◽  
Sensory Quality ◽  
Phenolic Content ◽  
Hot Water ◽  
Total Phenolic ◽  
Hibiscus Sabdariffa ◽  
Liquid Ratio ◽  
Herbal Tea ◽  
Soluble Solid ◽  
Solid Liquid

Roselle (Hibiscus sabdariffa L.) is an annual shrub popularly grown in tropical and subtropical areas. Although Roselle fruit has been used for a long time as a herbal tea due to its high content of bioactive compounds like phenolic acids and anthocyanins, the studies on the effects of the drying process and brewing conditions on the content of beneficial components and bioactivities of Roselle tea is limited. In this study, the influence of drying temperature on the retention of total phenolic content (TPC) and antioxidant capacity (AC) of the dried Roselle and the effects of brewing conditions including water temperature, liquid-solid ratio and brewing time on total soluble solid (TSS) content, total phenolic content, and antioxidant capacity of Roselle tea were investigated. The drying at 80 °C produced the dried Roselle with the highest retention of TPC (25.196 mg GAE/g) and AC (IC50 of 2.2 mg/mL for 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibition) and the highest sensory quality compared to the drying at other temperatures. The brewing process using hot water at 90 °C with the solid-liquid ratio of 1:10 (g/mL) for 30 min resulted in the highest TSS content (5.4 oBx), TPC (12.7 mg GAE/g dried Roselle) and AC (73.3% DPPH inhibition) of the Roselle tea. Thus, the drying at 80 °C combined with the brewing of dried Roselle for 30 min using 90 °C hot water with the solid-liquid ratio of 1:10 (g/mL) are recommended to produce Roselle tea with the highest content of beneficial ingredients.

scholarly journals Ultrasound-Assisted Extraction of Polyphenols from Crude Pollen

Antioxidants ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 322 ◽  
Author(s):  
Mircea Oroian ◽  
Florin Ursachi ◽  
Florina Dranca
Keyword(s):  
Extraction Efficiency ◽  
Phenolic Content ◽  
Extraction Yield ◽  
Total Phenolic ◽  
Optimum Conditions ◽  
Liquid Ratio ◽  
Ultrasound Assisted Extraction ◽  
Assisted Extraction ◽  
Ultrasonic Process ◽  
Solid Liquid

The aim of this study was to evaluate the extraction efficiency of polyphenols from crude pollen by an ultrasonic process. Prior to the polyphenols extraction, the crude pollen was defatted. The extraction from defatted pollen was carried out by varying four extraction parameters: ultrasonic amplitude (20%, 60% and 100%), solid/liquid ratio (10 g/L, 20 g/L and 30 g/L), temperature (35, 50 and 65 °C) and time (10, 20 and 30 min). The extracts were analyzed in terms of extraction yield (%), total phenolic content (TPC) and total flavones content (TFC). The extracted oil was analyzed in terms of fatty acids composition; myristic acid (159.1 µg × g−1) and cis-14-pentadecenoic acid (106.6 µg·g−1) were found in the highest amount in the pollen oil. The optimum conditions of extraction were determined and were, as follows: 100% amplitude of ultrasonic treatment, 30 g/L solid/liquid ratio, 40.85 °C and 14.30 min, which led to the extraction of 366.1 mg GAE/L of TPC and 592.2 mg QE/g of TFC, and also to an extraction yield of 1.92%.

Comparison of total phenolic contents and antioxidant capacities in mint genotypes used as spices / Baharat olarak kullanılan nane genotiplerinin toplam fenolik içerikleri ve antioksidan kapasitelerinin karşılaştırılması

2015 ◽  
Vol 40 (6) ◽  
Author(s):  
Mahfuz Elmastaş ◽  
İsa Telci ◽  
Hüseyin Akşit ◽  
Ramazan Erenler
Keyword(s):  
Antioxidant Capacity ◽  
Total Phenolic Content ◽  
Phenolic Content ◽  
Dry Weight ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Herbal Tea ◽  
Antioxidant Power ◽  
Phenolic Contents ◽  
Antioxidant Agents

AbstractObjective: Mint (Mentha spp.) genotypes used as spices are cultivated in Turkey and used for different purposes including herbal tea, spices, the cosmetics industry, and are used in folk medicine. While mint species have been used in traditional practices during humanity’s long history, there is limited research on the comparison of their antioxidant capacity and phenolic contents. This aim of the research is to compare antioxidant capacity and phenolic contents in mint clones to determine superior genotypes for herbal and spice usage and cultivation.Methods: Antioxidant capacity was evaluated by ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC). Total phenolic content in clones were determined by Folin-Ciocalteu method.Results: Maximum total phenolic content [28.27±3.95 μg gallic acid equivalent (GAE)/g dry weight (DW)] and FRAP activity 577.09±46.02 μmol Trolox equiv/g DW were obtained from Clone 13 (M. spicata), while M. piperita clones were higher for TEAC activity (800.02±1.10 μmol Trolox equiv/g DW). The results were first records for M. villoso nervata. FRAP and TEAC activities selected clones were correlated with total phenolic content (r=0.77; 0.73 respectively).Conclusion: According to the results, it can be suggested that Clone 13, Clone 5, (M. spicata) Clone 3 and Clone 8 (M. piperita) are more suitable for use as spice, herbal tea, and antioxidant agents. The clones must be selected for commercial cultivation by the grower and they can be used as spices and herbal teas.

scholarly journals Optimization of extraction conditions for polyphenols from the stem bark of Funtumia elastica (Funtum) utilizing response surface methodology

2021 ◽  
Vol 4 ◽  
pp. 46
Author(s):  
Theophilus Fadjare Frempong ◽  
Nathaniel Owusu Boadi ◽  
Mercy Badu
Keyword(s):  
Phenolic Compounds ◽  
Response Surface ◽  
Response Surface Method ◽  
Phenolic Content ◽  
Stem Bark ◽  
Total Phenolic ◽  
Liquid Ratio ◽  
Surface Method ◽  
Solid Liquid ◽  
The Impact

Background: The recovery of phenolic compounds is seen as an arduous task because phenolic compounds are available as free aglycones, as sugar or ester conjugates, or as polymers with several monomeric components. Furthermore, phenolic compounds do not disperse evenly and may be connected to cell walls, carbohydrates, or proteins. This study looks at the optimization of factors that affect the efficiency for the extraction of phenolic compounds from the stem-bark of Funtumia elastica. Methods: Five independent variables (solvent concentration, time, the temperature, solid-liquid ratio, and pH) of the extraction process were selected. Single factor analysis as well as the response surface method was used to evaluate the impact of the selected factors on the total phenolic content. The effect of the extraction factors on the phenolic content was statistically significant (p <0.05). For the response surface method, a five/factor, five/level central composite design used, and a fitted second-order polynomial regression model equation was used to show how the extraction parameters affected the total phenolic recovery. Results: The predicted value (R² of 0.5917) agreed with the adjusted value (R² of 0.7707). The residuals for response predictions were less than 5%. The optimal factors for the extraction were ethanol concentration of 75.99% v/v, extraction time of 193.86 minutes, temperature of 63.66°C, pH of 5.62, and solid-liquid ratio of 1:21.12 g/mL. Actual overall content of the phenolic compounds was validated at 82.83 ± 3.335 mg gallic acid equivalent (GAE) /g weight of extract, which agreed with the predicted response of 89.467 mg GAE/g of the dried extract under the optimal factors. Conclusions: The rich phenolic content of stem-bark of Funtumia elastica points to its potential as a functional medicinal product to alleviate diseases caused by oxidative stress such as asthma, breathing disorders, inflammation, and cardiovascular diseases.

scholarly journals Comparison of Phenolic Content and Antioxidant Activity for Fermented and Unfermented Rooibos Samples Extracted with Water and Methanol

Plants ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 16
Author(s):  
Eslam A. Hussein ◽  
Christopher Thron ◽  
Mehrdad Ghaziasgar ◽  
Mattia Vaccari ◽  
Jeanine L. Marnewick ◽  
...  
Keyword(s):  
Machine Learning ◽  
Antioxidant Capacity ◽  
Phenolic Content ◽  
Wide Spectrum ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Total Phenolic ◽  
Herbal Tea ◽  
Antioxidant Power ◽  
Water Extracts ◽  
Learning Analysis

Rooibos is brewed from the medicinal plant Aspalathus linearis. It has a well-established wide spectrum of bio-activity properties, which in part may be attributed to the phenolic antioxidant power. The antioxidant capacity (AOC) of rooibos is related to its total phenolic content (TPC). The relation between TPC and AOC of randomly selected 51 fermented (FR) and 47 unfermented (UFR) rooibos samples was studied after extraction using water and methanol separately. The resulted extracts were assessed using two antioxidant assays, trolox equivalent antioxidant capacity (TEAC) and ferric reducing antioxidant power (FRAP). The results were analyzed using both simple statistical methods and machine learning. The analysis showed different trends of TPC and AOC correlations of FR and UFR samples, depending on the solvent used for extraction. The results of the water extracts showed similar TPC and higher AOC of FR than UFR samples, while the methanolic extracted samples showed higher TPC and AOC of UFR than FR. As a result, the methanolic extracts showed better agreement between TPC and AOC than water extracts. Possible explanations are given for these observed results. Although, the current literature demonstrates direct correlations of the TPC and AOC of rooibos water extracts. This study showed deviation and highlighted the importance of solvent selection and analysis methodology as an important factor in determining the TPC/AOC correlation and subsequently the expectation of the actual health benefits of rooibos herbal tea. In particular, unfermented and fermented samples can be accurately identified on the basis of a combination of assays (any two of TPC, FRAP and TEAC), especially if methanol is the solvent used. Machine learning analysis of assay data provides nearly identical results with classical statistical analytical methods. This is the first report on machine learning analysis and comparison of the TPC and AOC of rooibos herbal tea extracted with methanol and water, and highlights the importance of using methanol as a solvent to evaluate its AOC.

Antioxidant Capacity and α-Amilase Inhibition by Avocado (Persea americana Mill) Peel and Red Ginger (Zingiber officinale var. Rubrum) based Functional Drink

2020 ◽  
Vol 3 (1) ◽  
pp. 135 ◽  
Author(s):  
I Made Wisnu Adhi Putra ◽  
Ketut Ayu Sukesi ◽  
Ni Putu Eny Sulistyadewi
Keyword(s):  
Antioxidant Capacity ◽  
Total Phenolic Content ◽  
Phenolic Content ◽  
Zingiber Officinale ◽  
Persea Americana ◽  
Hot Water ◽  
Antidiabetic Activity ◽  
Total Phenolic ◽  
Functional Beverages ◽  
Red Ginger

Avocado peel (Persea americana Mill) and red ginger (Zingiber officinale var. Rubrum) proved to have antidiabetic properties. However, there has been no research on the analysis of antidiabetic activity of the combination of avocado peel and red ginger in functional beverages. This study aims to make functional beverages from the combination of avocado peel and red ginger. Total phenolic content, antioxidant capacity, inhibition of the α-amylase activity, and public preferences towards functional beverages (organoleptic) were then evaluated. Functional beverages were made by brewing the powdered avocado peel and red ginger with 200 ml of hot water (96oC) for 5 minutes. The results showed that the increase of avocado peels amount in the combination coukd increase total phenolic content. The high antioxidant capacity was also found in samples with high content of avoccado peels. The results of inhibition of α-amylase enzyme activity did not show any significant differences. Organoleptic test results showed that there were no significant differences in each sample. The combination of avocado peel and red ginger has the potential to be an antidiabetic functional beverage.

scholarly journals Is the Household Microwave Recommended to Obtain Antioxidant-Rich Extracts from Lycium barbarum Leaves?

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 656
Author(s):  
Luna Pollini ◽  
Federica Ianni ◽  
Giuseppa Verducci ◽  
Francesca Blasi ◽  
Lina Cossignani
Keyword(s):  
Antioxidant Activity ◽  
Microwave Power ◽  
Phenolic Content ◽  
Irradiation Time ◽  
Total Phenolic ◽  
Liquid Ratio ◽  
Leaf Extracts ◽  
Lycium Barbarum ◽  
Plant Materials ◽  
Solid Liquid

Nowadays, much interest is devoted to the extraction of plant materials, considering also their waste and by-products, to obtain antioxidant-rich products. The effect of household microwave-assisted extraction (MAE) on the phenolic content and antioxidant activity of Lycium barbarum leaf extracts was investigated. An experimental design approach was adopted considering solid/liquid ratio (1, 3, and 5 g of leaves in 150 mL water), irradiation time (1, 3, and 5 min), and microwave power (300, 400, and 500 W) as independent variables. These three factors and their interactions were studied to evaluate the effect of MAE conditions on the responses of total phenolic content, antioxidant activity, and chlorogenic acid content. The results showed that the analytical parameters were positively influenced by the solid/liquid ratio and time. On the contrary, microwave power was inversely correlated with the investigated responses. This research revealed that microwave extraction conditions should be carefully monitored to obtain bioactive-rich aqueous extracts with high antioxidant activity. A comparison with household traditional methods showed an unexpected lower phenolic content and antioxidant activity for MAE extract in respect to the decoction and infusion. In fact, it was found that L. barbarum leaf infusion had the best functional properties, regarding the investigated characteristics. The outcome of this study has implications for raising awareness that household preparation conditions strongly affect the health properties of herbal extracts.

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