scholarly journals Epigallocatechin-3-gallate yield in different temperature gradients in green tea (Camellia sinensis) brewing

2018 ◽  
Author(s):  
Meng Hsuen Hsieh ◽  
Meng Ju Hsieh ◽  
Chi-Rei Wu ◽  
Wen-Huang Peng ◽  
Ming-Tsuen Hsieh ◽  
...  
Keyword(s):  
Green Tea ◽  
Camellia Sinensis ◽  
High Performance ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
Ultrasonic Bath ◽  
Antioxidative Effects ◽  
Natural Organic Compound ◽  
Discernible Difference

ABSTRACTIntroductionEpigallocatechin-3-gallate (EGCG) is a chemical catechin, a natural organic compound found in green teas with strong antioxidative effects. EGCG degrades or epimerizes according to temperature, fluctuating its concentration in green tea (Camellia sinensis). This study is conducted to determine the specified correlation between EGCG and tea temperature, and to conclude with the optimal temperature for EGCG yield.MethodsEGCG concentrations in different solutions of green tea are analyzed using a high-performance liquid chromatography (HPLC), with a diode array detector (DAD). The solutions are created from green tea brewed in water from 20°C to 100°C at increments of 20°C and undergo an ultrasonic bath of 30 minutes before being analyzed.ResultsThere is a discernible difference between EGCG concentrations in all temperatures. At 20, 40, 60, 80 and 100°C, the concentrations are 6.18 μg/mL, 32.37 μg/mL, 57.36 μg/mL, 36.13 μg/mL, and 44.85 μg/mL, respectively. EGCG concentration maximizes at 60°C. The lowest EGCG concentration yield is at 20°C.ConclusionThe results of our experiments lead us to recommend hot brewing over cold brewing for green tea if one wishes to maximize the potential of the effects of EGCG due to its higher concentration.

scholarly journals Analysis of the Mycosporine-Like Amino Acid (MAA) Pattern of the Salt Marsh Red Alga Bostrychia scorpioides

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 321
Author(s):  
Maria Orfanoudaki ◽  
Anja Hartmann ◽  
Julia Mayr ◽  
Félix L. Figueroa ◽  
Julia Vega ◽  
...  
Keyword(s):  
Amino Acids ◽  
High Performance Liquid Chromatography ◽  
High Performance ◽  
Red Alga ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
The Past ◽  
Specific Species

This study presents the validation of a high-performance liquid chromatography diode array detector (HPLC-DAD) method for the determination of different mycosporine-like amino acids (MAAs) in the red alga Bostrychia scorpioides. The investigated MAAs, named bostrychines, have only been found in this specific species so far. The developed HPLC-DAD method was successfully applied for the quantification of the major MAAs in Bostrychia scorpioides extracts, collected from four different countries in Europe showing only minor differences between the investigated samples. In the past, several Bostrychia spp. have been reported to include cryptic species, and in some cases such as B. calliptera, B. simpliciuscula, and B. moritziana, the polyphyly was supported by differences in their MAA composition. The uniformity in the MAA composition of the investigated B. scorpioides samples is in agreement with the reported monophyly of this Bostrychia sp.

scholarly journals Simultaneous Extraction Optimization and Analysis of Flavonoids from the Flowers of Tabernaemontana heyneana by High Performance Liquid Chromatography Coupled to Diode Array Detector and Electron Spray Ionization/Mass Spectrometry

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Thiyagarajan Sathishkumar ◽  
Ramakrishnan Baskar ◽  
Mohan Aravind ◽  
Suryanarayanan Tilak ◽  
Sri Deepthi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Shake Flask ◽  
Orthogonal Design ◽  
Array Detector ◽  
Diode Array ◽  
Ionization Mass ◽  
Diode Array Detector

Flavonoids are exploited as antioxidants, antimicrobial, antithrombogenic, antiviral, and antihypercholesterolemic agents. Normally, conventional extraction techniques like soxhlet or shake flask methods provide low yield of flavonoids with structural loss, and thereby, these techniques may be considered as inefficient. In this regard, an attempt was made to optimize the flavonoid extraction using orthogonal design of experiment and subsequent structural elucidation by high-performance liquid chromatography-diode array detector-electron spray ionization/mass spectrometry (HPLC-DAD-ESI/MS) techniques. The shake flask method of flavonoid extraction was observed to provide a yield of 1.2±0.13 (mg/g tissue). With the two different solvents, namely, ethanol and ethyl acetate, tried for the extraction optimization of flavonoid, ethanol (80.1 mg/g tissue) has been proved better than ethyl acetate (20.5 mg/g tissue). The optimal conditions of the extraction of flavonoid were found to be 85°C, 3 hours with a material ratio of 1 : 20, 75% ethanol, and 1 cycle of extraction. About seven different phenolics like robinin, quercetin, rutin, sinapoyl-hexoside, dicaffeic acid, and two unknown compounds were identified for the first time in the flowers of T. heyneana. The study has also concluded that L16 orthogonal design of experiment is an effective method for the extraction of flavonoid than the shake flask method.

scholarly journals Single-Laboratory Validation of a High-Performance Liquid Chromatographic-Diode Array Detector-Fluorescence Detector/Mass Spectrometric Method for Simultaneous Determination of Water-Soluble Vitamins in Multivitamin Dietary Tablets

2009 ◽  
Vol 92 (2) ◽  
pp. 680-688 ◽  
Author(s):  
Pei Chen ◽  
Renata Atkinson ◽  
Wayne R Wolf
Keyword(s):  
Formic Acid ◽  
Dietary Supplements ◽  
High Performance ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
Fluorescence Detector ◽  
Liquid Chromatographic ◽  
Single Laboratory

Abstract The purpose of this study was to develop a single-laboratory validated (SLV) method using high-performance liquid chromatography with different detectors diode array detector (DAD); fluorescence detector (FLD); and mass spectrometry (MS) for determination of 7 B-complex vitamins (B1-thiamin, B2-riboflavin, B3-nicotinamide, B6-pyridoxine, B9-folic acid, pantothenic acid, and biotin) and vitamin C in multivitamin/multimineral dietary supplements. The method involves the use of a reversed-phase octadecylsilyl column (4 m, 250 2.0 mm id) and a gradient mobile phase profile. Gradient elution was performed at a flow rate of 0.25 mL/min. After a 5 min isocratic elution at 100 A (0.1 formic acid in water), a linear gradient to 50 A and 50 B (0.1 formic acid in acetonitrile) at 15 min was employed. Detection was performed with a DAD as well as either an FLD or a triple-quadrupole MS detector in the multiple reaction monitoring mode. SLV was performed using Standard Reference Material (SRM) 3280 Multivitamin/Multimineral Tablets, being developed by the National Institute of Standards and Technology, with support by the Office of Dietary Supplements of the National Institutes of Health. Phosphate buffer (10 mM, pH 2.0) extracts of the NIST SRM 3280 were analyzed by the liquid chromatographic (LC)-DAD-FLD/MS method. Following extraction, the method does not require any sample cleanup/preconcentration steps except centrifugation and filtration.

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