Chlorogenic acid is formed by condensation and dehydration of caffeic acid and quinic acid. It is a kind of phenylpropanoid substance synthesized by the intermediate product of crystalline pentose phosphate in the process of aerobic respiration of plants. It widely exists in plant species, with a high content in honeysuckle and eucommia. A large number of studies have shown that chlorogenic acid has antiviral, antibacterial, antitumor and immunomodulatory effects. As an effective antiviral chemical monomer, chlorogenic acid has a good inhibitory effect on most viruses.
Hu Kejie et al. found that chlorogenic acid has a strong inhibitory effect on common respiratory viruses (syncytial virus, Sarkozy and adenovirus) in vitro .（胡克杰等. 氯原酸体外抗病毒作用研究哈尔滨医科大学学报[J]. 2001第06期，第35-37页）
Li Lijing and other researchers have proved that the extract and its effective components, chlorogenic acid and caffeic acid, have a strong inhibitory effect on influenza virus and Newcastle disease virus, chlorogenic acid has a inhibitory effect on the neuraminidase activity of MDCK cells infected with influenza virus at a certain concentration, and has a promoting effect on the induction of human whole blood cell interferon by Newcastle disease virus (NDV). (李丽静,等.返魂草提取物及其有效成分抗病毒机制的研究[J].陕西中医学院学报,2004)
Pan Yanyan et al. found chlorogenic acid extracted from honeysuckle is effective in inhibiting FM1 strain of influenza A virus by hemagglutination test. Chlorogenic acid of 25-100mg / ml had preventive and therapeutic effects on chicken embryos infected with influenza A virus, and the preventive effect of 100mg / ml was significantly better than that of ribavirin group.（潘曌曌等，金银花提取物体外抗甲型流感病毒 FM1 株的研究[J].中国中医药信息杂志.2007.）
Sheng jiehuang et al. showed that chlorogenic acid has obvious inhibitory effect on HSV-1 infection in vitro and could effectively prevent virus infection, but has no direct killing effect on virus. (盛卸晃,等.绿原酸体外抗单纯疱疹病毒作用[J],Chin J Nat Med.2008,6(3))
Wang Xuebing et al. observed whether chlorogenic acid obtained from honeysuckle can block or inhibit PK-15 cytopathic effect (CPE) of porcine parvovirus (PPV) .The results show that chlorogenic acid has significant inhibitory and blocking effects in vitro. (王学兵,等.绿原酸的提取及其对猪细小病毒的体外作用研究[J].中国畜牧兽医.2008)
Wang GF reported the inhibitory effect of chlorogenic acid on hepatitis B virus (HBsAg and HBeAg), which significantly inhibited the secretion of HBsAg and HBeAg in HepG2.2.15 cells.(Wang GF, et al. Anti hepatis B virus activity of chlorogenic acid, quinic acid and caffeic acid in vivo and in vitro [J]. Antiviral res. 2009 Aug; 83 (2): 186-90)
Chen JUANJUAN et al. found that chlorogenic acid has significant effect of anti human cytomegalovirus in vitro by MTT and CPE methods. (陈娟娟,等.绿原酸体外抗人巨细胞病毒的实验研究[J].Herald of Medicine Vol,2009.28 (9)）
Keikoikeda et al. reported that caffeic acid, a component of chlorogenic acid, can inhibit the proliferation of HSV-1. Caffeic acid has a significant anti-HSV-1 effect and is likely to be a specific site of caffeic acid binding to the virus or some key molecules of virus replication. （Keikoikeda,et al Inhibition of multiplication of herpes simplex virus by caffeic acid [J]. International J Molecular medicine.2011）
Qinhai Ma et al. found that Shuang–Huang–Lian (the main bioactive compounds include chlorogenic acid, scutellaria baicalensis georgi and forsythin A) could prevent the attachment, internalization and replication of high concentration human adenovirus III (hadv3) under laboratory conditions. （Qinhai Ma, et al.Comparative Study on the Antivirus Activity of Shuang–Huang–Lian Injectable Powder and Its Bioactive Compound Mixture against Human Adenovirus III In Vitro[J]. Viruses 2017, 9, 79)
Jing Ru Weng et al. disclosed that the ethanol extract from the stem of Elaeagnus hepatica (its main components are caffeic acid and chlorogenic acid) has a strong potential of anti HCoV-NL63. (Jing-Ru Weng et al. Antiviral activity of Sambucus FormosanaNakai ethanol extract and related T phenolic acid constituents against human coronavirus NL63[J]. Virus Research 273 (2019) 197767)
