title: Immune enhancement effects and extraction optimization of polysaccharides from Citrus aurantium L. var. amara Engl.
abstract: The crude polysaccharides of Citrus aurantium L. var. amara Engl (CAVAPs) were extracted and their bioactivities including DPPH radical scavenging activity, cytotoxicity to human breast cancer cells, MCF-7, as well as lung cancer cells, HCC827, and their immune-enhancement activity were evaluated. Results showed that CAVAPs exhibited better immunoenhancement activity compared to the DPPH radical scavenging and anticancer activities. Subsequently, the immune enhancement activity of CAVAPs on RAW264.7 cells was further observed and the results displayed that CAVAPs could significantly stimulate the production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in RAW264.7 cells, and promote the mRNA expression levels of inducible nitric oxide synthase (iNOS), TNF-α, interleukin-1 beta (IL-1β), and IL-6. Furthermore, western blot analysis demonstrated that the phosphorylated extracellular signal-regulated kinase (ERK), phosphorylated c-Jun N-terminal kinase (JNK), phosphorylated p38 and phosphorylated p65 were all remarkably increased in CAVAP-treated RAW264.7 cells. All these results indicated that CAVAPs might activate macrophages through the mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathway. Additionally, a three-level-three-factor Box-Behnken design (BBD) was performed to optimize the extraction process of CAVAPs for the purpose of application and further research. The maximum extraction yield reached 4.49 ± 0.25%.
authors.affiliation: College of Food and Bioengineering, South China University of Technology, Guangzhou, 510640, China. jgjiang@scut.edu.cn.
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: Shen
authors.affiliation: College of Food and Bioengineering, South China University of Technology, Guangzhou, 510640, China. jgjiang@scut.edu.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.affiliation: College of Food and Bioengineering, South China University of Technology, Guangzhou, 510640, China. jgjiang@scut.edu.cn.
authors.forename: Jian-Guo
authors.identifier: http://orcid.org/0000-0002-3361-6149
authors.initials: JG
authors.lastname: Jiang
authors.affiliation: The Second Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou 510120, China. zhuwei9201@163.com.
authors.forename: Chao-Yang
authors.initials: CY
authors.lastname: Zheng
authors.affiliation: The Second Affiliated Hospital, Guangzhou University of Chinese Medicine, Guangzhou 510120, China. zhuwei9201@163.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
mesh_terms: D000818:Animals; D005591:Chemical Fractionation / Q000379:methods*; D002957:Citrus / Q000737:chemistry*; D006801:Humans; D007155:Immunologic Factors / Q000302:isolation & purification* / Q000494:pharmacology*; D053583:Interleukin-1beta / Q000235:genetics / Q000276:immunology; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology; D061986:MCF-7 Cells; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D016328:NF-kappa B / Q000235:genetics / Q000276:immunology; D010936:Plant Extracts / Q000302:isolation & purification* / Q000494:pharmacology*; D011134:Polysaccharides / Q000302:isolation & purification* / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology
chemical_list: D007155:Immunologic Factors; D053583:Interleukin-1beta; D015850:Interleukin-6; D016328:NF-kappa B; D010936:Plant Extracts; D011134:Polysaccharides; D014409:Tumor Necrosis Factor-alpha