\nQuercetin was weighed and dissolved in HPLC-grade methanol to make a 25 ppm stock solution. This solution was stored in the refrigerator.<\/p>\n
Sample Preparation:<\/strong> HPLC System:<\/strong> Identification Results:<\/strong> Content Calculation:<\/strong> Average quercetin content: 0.00425 \u00b1 0.0004 %<\/p>\n Preparation of Comparison Solution:<\/strong> Sample Preparation:<\/strong> Quercetin Calibration Curve Results:<\/strong> Quercetin calibration curve<\/p>\n Sample Results:<\/strong> OHT CSTRLY product contains 0.00425 \u00b1 0.0004% quercetin and total flavonoids of 0.101 \u00b1 0.004 g QE\/100 g sample. Based on HPLC and spectrophotometry tests, quercetin compounds were clearly detected, and the total flavonoid content could be accurately calculated using standard methods.<\/p>\n <\/div>","protected":false},"author":1,"featured_media":0,"menu_order":3,"template":"","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"reference":[2],"institution":[19],"class_list":["post-2055","research","type-research","status-publish","hentry","reference-cs-30-csa-300","institution-itb"],"acf":[],"_links":{"self":[{"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/research\/2055","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/research"}],"about":[{"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/types\/research"}],"author":[{"embeddable":true,"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/users\/1"}],"version-history":[{"count":14,"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/research\/2055\/revisions"}],"predecessor-version":[{"id":2195,"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/research\/2055\/revisions\/2195"}],"wp:attachment":[{"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/media?parent=2055"}],"wp:term":[{"taxonomy":"reference","embeddable":true,"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/reference?post=2055"},{"taxonomy":"institution","embeddable":true,"href":"https:\/\/drrkiwn1018.com\/en\/wp-json\/wp\/v2\/institution?post=2055"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\nCSTRLY product powder was weighed and dissolved in HPLC grade methanol at a concentration of 218.030 ppm, then sonicated for 30 minutes and filtered using a 0.45 \u00b5m syringe filter. The solution was stored in a refrigerator.<\/p>\n
\nThe method refers to Rizaldy et al. (2022) with a 360 nm UV detector. The mobile phase was water-methanol with a linear gradient of 40\u201360% for 5 minutes, then 70% methanol until the 10th minute, and a 40% methanol gradient until the 15th minute. The flow rate was 1 mL\/minute. The quercetin content was determined using the one-point method.<\/p>\n
\nThe chromatogram shows that the retention time of the sample is almost the same as the comparator, indicating the presence of quercetin in the product.<\/p>\n![\"\"](\"https:\/\/daunteratai.kudos.nyc\/wp-content\/uploads\/2025\/06\/Kuersetin-1-1-1024x717.jpg\")
<\/p>\n
\nBased on the AUC chromatogram and one point method, the following was obtained:
\n![\"\"](\"https:\/\/daunteratai.kudos.nyc\/wp-content\/uploads\/2025\/06\/Kuersetin-3-1024x310.jpg\")
<\/p>\n
\nDetermination of Total Flavonoid Content<\/h3>\n
\n12.5 mg of quercetin was dissolved in 25 mL of analytical grade methanol as a stock solution. A dilution of 40\u2013110 \u00b5g\/mL was performed. The solution was mixed with 10% aluminum chloride, 1 M sodium acetate, and distilled water, then incubated for 30 minutes. Absorbance was measured at \u03bb 415 nm.<\/p>\n
\nCSTRLY product powder was dissolved in methanol, sonicated for 30 minutes, filtered, and diluted to a concentration of 63,775 ppm. Each solution was measured in six replicates.<\/p>\n
\nQuercetin calibration curve data
\n![\"\"](\"https:\/\/daunteratai.kudos.nyc\/wp-content\/uploads\/2025\/06\/Kuersetin-4-1024x352.jpg\")
<\/p>\n![\"\"](\"https:\/\/daunteratai.kudos.nyc\/wp-content\/uploads\/2025\/06\/Kuersetin-5-e1781146947781-1024x656.jpg\")
<\/p>\n
\nCSTRLY product contains total flavonoids of 0.101 \u00b1 0.004 g QE\/100 g sample.
\n![\"\"](\"https:\/\/daunteratai.kudos.nyc\/wp-content\/uploads\/2025\/06\/Kuersetin-6-1024x453.jpg\")
<\/p>\nConclusion<\/h3>\n