{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T15:09:00Z","timestamp":1770908940151,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T00:00:00Z","timestamp":1770854400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Young and Middle-Aged Academic and Technological Leaders of Yunnan Province","award":["202205AC160049"],"award-info":[{"award-number":["202205AC160049"]}]},{"name":"Yunnan Yuanfang Biomedical Co., Ltd.-Zhao Ping Expert Basic Scientific Research Workstation","award":["202501BD070001-027"],"award-info":[{"award-number":["202501BD070001-027"]}]},{"name":"Key Research and Development Program of Yunnan Provincial Science and Technology Department","award":["202503AC100002"],"award-info":[{"award-number":["202503AC100002"]}]},{"name":"Yunnan Provincial Gao Jinming Expert Workstation","award":["202605AF350122"],"award-info":[{"award-number":["202605AF350122"]}]},{"name":"Yunnan Foreign Expert Program","award":["202505AO120060"],"award-info":[{"award-number":["202505AO120060"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>This study expands research on Cinchona calisaya, which has traditionally focused on alkaloids, to address the insufficient comprehensive utilization of its resources. It is the first to explore the feasibility of extracting phenolic compounds from Cinchona calisaya using subcritical water extraction (SCWE) technology. Combining single-factor experiments with Box\u2013Behnken design-response surface methodology (BBD-RSM), the study optimized three key process parameters, namely extraction temperature, extraction time, and liquid-to-solid ratio, with total phenolic content (TPC) as the response variable. Optimal extraction conditions were 165 \u00b0C, 20 min, and a liquid-to-solid ratio of 70:1 mL\/g. Under these conditions, the TPC values were 98.41 \u00b1 1.06 mg\/g for bark and 37.96 \u00b1 1.18 mg\/g for heartwood, significantly higher than those obtained by traditional hot water extraction (THWE). Ultra-high performance liquid chromatography-Q-orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) identified 1198 and 1156 metabolites in the bark and heartwood, respectively, with a higher content of phenolic compounds in the heartwood. The extracts showed strong inhibitory activity against Staphylococcus aureus, weak inhibitory activity against Escherichia coli at high concentrations, and no inhibitory effect on Candida albicans. This study provides a theoretical basis and technical support for the comprehensive utilization of Cinchona calisaya resources and the green development of natural antioxidants and antimicrobial agents.<\/jats:p>","DOI":"10.3390\/molecules31040635","type":"journal-article","created":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T14:06:16Z","timestamp":1770905176000},"page":"635","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Optimization of Subcritical Water Extraction Process for Polyphenols from Cinchona calisaya and Their Activity Analysis"],"prefix":"10.3390","volume":"31","author":[{"given":"Guangxin","family":"Li","sequence":"first","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Wood and Bamboo Biomass Materials, Southwest Forestry University, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yujie","family":"Zhou","sequence":"additional","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Wood and Bamboo Biomass Materials, Southwest Forestry University, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dong","family":"Xie","sequence":"additional","affiliation":[{"name":"Yunnan Plant Bioactive Ingredients Industry-University Joint Research Center, Yunnan Yuanfang Biopharmaceutical Co., Ltd., Qujing 655000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingwen","family":"Zhang","sequence":"additional","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Wood and Bamboo Biomass Materials, Southwest Forestry University, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhengshan","family":"Hu","sequence":"additional","affiliation":[{"name":"Yunnan Plant Bioactive Ingredients Industry-University Joint Research Center, Yunnan Yuanfang Biopharmaceutical Co., Ltd., Qujing 655000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuanping","family":"He","sequence":"additional","affiliation":[{"name":"Yunnan Plant Bioactive Ingredients Industry-University Joint Research Center, Yunnan Yuanfang Biopharmaceutical Co., Ltd., Qujing 655000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lihua","family":"Zou","sequence":"additional","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Wood and Bamboo Biomass Materials, Southwest Forestry University, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ping","family":"Zhao","sequence":"additional","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Wood and Bamboo Biomass Materials, Southwest Forestry University, Kunming 650224, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0295-337X","authenticated-orcid":false,"given":"Yingjun","family":"Zhang","sequence":"additional","affiliation":[{"name":"Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4095-2017","authenticated-orcid":false,"given":"Xiaoqin","family":"Yang","sequence":"additional","affiliation":[{"name":"Yunnan Provincial Key Laboratory of Wood and Bamboo Biomass Materials, Southwest Forestry University, Kunming 650224, China"},{"name":"Yunnan Plant Bioactive Ingredients Industry-University Joint Research Center, Yunnan Yuanfang Biopharmaceutical Co., Ltd., Qujing 655000, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5904-1822","authenticated-orcid":false,"given":"Sengkew","family":"Wee","sequence":"additional","affiliation":[{"name":"Faculty of Bioengineering and Technology, University of Malaysia Kelantan, Kota Bharu 16100, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,12]]},"reference":[{"key":"ref_1","first-page":"2737","article-title":"Historical story on natural medicinal chemistry: Isolation, structure, and total synthesis of quinine","volume":"45","author":"Guo","year":"2014","journal-title":"Chin. 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