{{chembox | Reference = | Name = Palmatine | ImageFile1 = Palmatine v2.svg | ImageClass1 = skin-invert-image | ImageSize1 = 200px | IUPACName = 2,3,9,10-Tetramethoxy-5,6-dihydroisoquinolino[2,1-b]isoquinolin-7-ium | OtherNames = Berbericinine |Section1={{Chembox Identifiers | InChI = 1/C21H25NO4/c1-23-18-6-5-13-9-17-15-11-20(25-3)19(24-2)10-14(15)7-8-22(17)12-16(13)21(18)26-4/h5-6,10-11,17H,7-9,12H2,1-4H3 | InChIKey = AEQDJSLRWYMAQI-UHFFFAOYAT | PubChem = 19009 | ChEMBL = 274189 | CASNo = 3486-67-7 | ChemSpiderID = 5224 | UNII = G50C034217 | KEGG_Ref = {{keggcite|correct|kegg}} | KEGG = C05315 | SMILES = O(c1c4c(ccc1OC)CC3c2c(cc(OC)c(OC)c2)CCN3C4)C }} |Section2={{Chembox Properties | C = 21 | H = 22 | N = 1 | O = 4 | Formula_Charge = + | Density = 1.23 g/cm<sup>3</sup> | MeltingPt = | BoilingPtC = | BoilingPt_notes = | Solubility = }} }}
'''Palmatine''' is a protoberberine alkaloid found in several plants including ''Coptis chinensis''<ref>{{Cite journal|last1=Yang|first1=Seong Baek|last2=Kim|first2=Eun Hee|last3=Kim|first3=Seung Hee|last4=Kim|first4=Young Hun|last5=Oh|first5=Weontae|last6=Lee|first6=Jin-Tae|last7=Jang|first7=Young-Ah|last8=Sabina|first8=Yeasmin|last9=Ji|first9=Byung Chul|last10=Yeum|first10=Jeong Hyun|date=2018-09-17|title=Electrospinning Fabrication of Poly(vinyl alcohol)/Coptis chinensis Extract Nanofibers for Antimicrobial Exploits|journal=Nanomaterials|volume=8|issue=9|page=734|doi=10.3390/nano8090734|issn=2079-4991|pmc=6164458|pmid=30227671|doi-access=free}}</ref> (Rhizoma coptidis, chinese goldthread), ''Corydalis yanhusuo'',<ref>{{Cite journal|last1=Zhang|first1=Qian|last2=Chen|first2=Cen|last3=Wang|first3=Feng-Qin|last4=Li|first4=Chun-Hong|last5=Zhang|first5=Qi-Hui|last6=Hu|first6=Yuan-Jia|last7=Xia|first7=Zhi-Ning|last8=Yang|first8=Feng-Qing|date=2016-12-01|title=Simultaneous screening and analysis of antiplatelet aggregation active alkaloids from Rhizoma Corydalis|journal=Pharmaceutical Biology|volume=54|issue=12|pages=3113–3120|doi=10.1080/13880209.2016.1211714|issn=1388-0209|pmid=27558975|doi-access=free}}</ref> ''Tinospora cordifolia''<ref>{{Cite journal|last1=Kumar|first1=Peeyush|last2=Srivastava|first2=Vartika|last3=Chaturvedi|first3=Rakhi|last4=Sundar|first4=Durai|last5=Bisaria|first5=V. S.|date=2017-08-01|title=Elicitor enhanced production of protoberberine alkaloids from in vitro cell suspension cultures of Tinospora cordifolia (Willd.) Miers ex Hook. F. & Thoms|journal=Plant Cell, Tissue and Organ Culture |language=en|volume=130|issue=2|pages=417–426|doi=10.1007/s11240-017-1237-0|s2cid=41951538|issn=1573-5044}}</ref> (gurjo, heart-leaved moonseed), ''Tinospora sagittata'',<ref>{{Cite journal|last1=Rong|first1=Qian|last2=Xu|first2=Min|last3=Dong|first3=Qi|last4=Zhang|first4=Yuli|last5=Li|first5=Yinglun|last6=Ye|first6=Gang|last7=Zhao|first7=Ling|date=2016-08-30|title=In vitro and in vivo bactericidal activity of Tinospora sagittata (Oliv.) Gagnep. var. craveniana (S.Y.Hu) Lo and its main effective component, palmatine, against porcine Helicobacter pylori|url= |journal=BMC Complementary and Alternative Medicine|volume=16|issue=1|page=331|doi=10.1186/s12906-016-1310-y|issn=1472-6882|pmc=5006617|pmid=27576439 |doi-access=free }}</ref> ''Phellodendron amurense''<ref>{{Cite journal|last1=Sun|first1=Minglong|last2=Xu|first2=Lijiao|last3=Peng|first3=Yingli|last4=Liu|first4=Tong|last5=Zhang|first5=Yuhong|last6=Zhou|first6=Zhiqiang|date=2016-04-01|title=Multiscale analysis of the contents of palmatine in the Nature populations of Phellodendron amurense in Northeast China|journal=Journal of Forestry Research|language=en|volume=27|issue=2|pages=265–272|doi=10.1007/s11676-015-0200-3|s2cid=15369649|issn=1993-0607}}</ref> (amur cork tree), and ''Stephania yunnanensis.''<ref>{{Cite journal|last1=Xin|first1=Aiyi|last2=Zhang|first2=Yaming|last3=Zhang|first3=Yanxia|last4=Di|first4=Duolong|last5=Liu|first5=Junxi|date=October 2018|title=Development of an HPLC-DAD method for the determination of five alkaloids in Stephania yunnanensis Lo and in rat plasma after oral dose of Stephania yunnanensis Lo extracts|journal=Biomedical Chromatography|volume=32|issue=10|article-number=e4292|doi=10.1002/bmc.4292|issn=1099-0801|pmid=29782649|s2cid=29167917 }}</ref>
It is the major component of the protoberberine extract from ''Enantia chlorantha''.<ref>{{cite journal | author = Virtanen P., Njimi T., Ekotto Mengata D. | title = Clinical trials of hepatitis cure with protoberberine alkaloids of Enantia Chlorantha | journal = Eur. J. Clin. Pharmacol. | volume = 36 | pages = A123 | date = 1989 }}</ref>{{bsn|date=December 2024}}
It has been studied for its potential use in the treatment of jaundice, dysentery, hypertension, inflammation, and liver-related diseases.<ref>{{cite journal |vauthors=Bhadra K, Kumar GS |title=Therapeutic potential of nucleic acid-binding isoquinoline alkaloids: Binding aspects and implications for drug design |journal=Medicinal Research Reviews |date=January 2010 |pmid=20077560 |doi=10.1002/med.20202 |pages= 821–862|volume=31|issue=6 |s2cid=206250975 |doi-access=free }}</ref> This compound also has weak ''in vitro'' activity against flavivirus.<ref>{{cite journal | doi = 10.1007/s00705-010-0702-4 | title = Identification of palmatine as an inhibitor of West Nile virus | date = 2010 | last1 = Jia | first1 = Fan | last2 = Zou | first2 = Gang | last3 = Fan | first3 = Jingjing | last4 = Yuan | first4 = Zhiming | journal = Archives of Virology | volume = 155 | issue = 8 | pages = 1325–1329 | pmid = 20496087 }}</ref>
==Biosynthesis== The biosynthesis of palmatine starts with tyrosine and proceeds via (''S'')-reticuline in a pathway leading to benzylisoquinoline alkaloids.<ref>{{cite journal |last1=Tian |first1=Ya |last2=Kong |first2=Lingzhe |last3=Li |first3=Qi |last4=Wang |first4=Yifan |last5=Wang |first5=Yongmiao |last6=An |first6=Zhoujie |last7=Ma |first7=Yuwei |last8=Tian |first8=Lixia |last9=Duan |first9=Baozhong |last10=Sun |first10=Wei |last11=Gao |first11=Ranran |last12=Chen |first12=Shilin |last13=Xu |first13=Zhichao |title=Structural diversity, evolutionary origin, and metabolic engineering of plant specialized benzylisoquinoline alkaloids |journal=Natural Product Reports |date=2024 |volume=41 |issue=11 |pages=1787–1810 |doi=10.1039/d4np00029c |pmid=39360417 }}</ref><ref>{{Cite book |ref=Begley |author=Begley, Tadhg P. |year=2009 |title=Encyclopedia of Chemical Biology |volume=10 |issue=9 |pages=1569–1570 |publisher=Wiley |isbn=978-0-471-75477-0 |doi=10.1002/cbic.200900262}}</ref> The final step is catalysed by the enzyme tetrahydroberberine oxidase, which oxidises tetrahydropalmatine:<ref name=Ullmann>{{cite book |last1=Mascavage |first1=Linda M. |last2=Jasmin |first2=Serge |last3=Sonnet |first3=Philip E. |last4=Wilson |first4=Michael |last5=Dalton |first5=David R. |title=Ullmann's Encyclopedia of Industrial Chemistry |chapter=Alkaloids |date=2010 |doi=10.1002/14356007.a01_353.pub2 |isbn=978-3-527-30385-4 |page=54}}</ref><ref name=KEGG>{{KEGG enzyme|1.3.3.8}}</ref>
{{chemrxn|width=50%| {{chemrxn/cpd|tetrahydropalmatine }} {{chemrxn/txt|+ {{chem2|H+}} }} {{chemrxn/arw|fwd_in={{chem2|2 O2}}|fwd_out={{chem2|2 H2O2}} }} {{chemrxn/cpd|palmatine }} }}
Alternatively, a methylation reaction catalysed by columbamine O-methyltransferase produces palmatine from columbamine. The methyl group comes from the cofactor, S-adenosyl methionine (SAM). This enzyme was characterised from ''Berberis wilsoniae''.<ref>{{cite journal | vauthors = Rueffer M, Amann M, Zenk MH | date = 1986 | title = S-Adenosyl-L-methionine:columbamine O-methyltransferase, a compartmentalized enzyme in protoberberine biosynthesis | journal = Plant Cell Reports | volume = 5 | issue = 3 | pages = 182–185 | doi = 10.1007/BF00269113 | pmid = 24248127 | bibcode = 1986PCelR...5..182R }}</ref>
{{chemrxn|width=65%| {{chemrxn/cpd|columbamine }} {{chemrxn/txt|+ SAM }} {{chemrxn/arw| }} {{chemrxn/cpd|palmatine }} {{chemrxn/txt|+ SAH }} }}
==Metabolism== In ''Corydalis cava'', palmatine is converted to corydaline by the enzyme corydaline synthase. The methyl group comes from SAM and the reaction also requires nicotinamide adenine dinucleotide phosphate (NADPH).<ref>{{cite journal |vauthors=Rueffer M, Bauer W, Zenk MH | date = 1994 | title = The formation of corydaline and related alkaloids in ''Corydalis cava'' in vivo and in vitro | journal = Can. J. Chem. | volume = 72 | issue = 1 | pages = 170–175 | doi = 10.1139/v94-026 | bibcode = 1994CaJCh..72..170R | doi-access = free }}</ref>
{{chemrxn|width=70%| {{chemrxn/cpd|palmatine }} {{chemrxn/txt|+ SAM<br>+ 2 NADPH }} {{chemrxn/arw|fwd_in={{chem2|H+}} }} {{chemrxn/cpd|corydaline }} {{chemrxn/txt|+ SAH<br>+ 2 NADP<sup>+</sup> }} }}
== Pharmacology ==
=== Neuroprotective activity === {{Verify sources|date=January 2026}} Palmatine is an inhibitor of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and neuraminidase-1 (NA-1), and has potential applications in the therapy of Alzheimer's disease. It was found that the positively charged nitrogen on palmatine binds in the gorge of active sire of AChE.<ref>{{Cite journal|date=2007-04-10|title=Acetylcholinesterase inhibitors from plants|url=https://www.sciencedirect.com/science/article/abs/pii/S094471130700030X|journal=Phytomedicine|language=en|volume=14|issue=4|pages=289–300|doi=10.1016/j.phymed.2007.02.002|issn=0944-7113|last1=Mukherjee|first1=Pulok K.|last2=Kumar|first2=Venkatesan|last3=Mal|first3=Mainak|last4=Houghton|first4=Peter J.|pmid=17346955|url-access=subscription}}</ref>{{Better source needed|reason=The current source is insufficiently reliable (WP:NOTRS). Does this source actually verify these claims?|date=January 2026}}
Research show that palmatine had antidepressant effect. It was achieved by regulating brain catalase levels, monoamine oxidase-A (MAO-A) activity, lipid peroxidation, plasma nitrite and corticosterone levels.<ref>{{Cite journal|date=2014-02-01|title=Behavioral and biochemical evidences for antidepressant-like activity of palmatine in mice subjected to chronic unpredictable mild stress|url=https://www.sciencedirect.com/science/article/abs/pii/S1734114014000024|journal=Pharmacological Reports|language=en|volume=66|issue=1|pages=1–9|doi=10.1016/j.pharep.2013.06.001|issn=1734-1140|last1=Dhingra|first1=Dinesh|last2=Bhankher|first2=Arun|pmid=24905299|s2cid=14391622 |url-access=subscription}}</ref>
=== Regulating blood lipid activity === Palmatine achieved hypoglycemic effects by inducing insulin release and insulin-mimicking activity.<ref>{{Cite journal|last1=Patel|first1=Mayurkumar B.|last2=Mishra|first2=Shrihari|date=September 2011|title=Hypoglycemic activity of alkaloidal fraction of Tinospora cordifolia|journal=Phytomedicine|volume=18|issue=12|pages=1045–1052|doi=10.1016/j.phymed.2011.05.006|pmid=21665451|issn=0944-7113}}</ref><ref>{{Cite journal|last1=Ma|first1=Bingxin|last2=Tong|first2=Jing|last3=Zhou|first3=Gao|last4=Mo|first4=Qigui|last5=He|first5=Jingsheng|last6=Wang|first6=Youwei|date=March 2016|title=Coptis chinensis inflorescence ameliorates hyperglycaemia in 3T3-L1 preadipocyte and streptozotocin-induced diabetic mice|journal=Journal of Functional Foods|volume=21|pages=455–462|doi=10.1016/j.jff.2015.12.021|issn=1756-4646}}</ref> In addition, studies found that palmatine also inhibited the activity of lens aldose reductase,<ref>{{Cite journal|last1=Patel|first1=Mayurkumar B.|last2=Mishra|first2=Shrihari|date=2012-02-01|title=Isoquinoline Alkaloids from Tinospora cordifolia Inhibit Rat Lens Aldose Reductase|journal=Phytotherapy Research|volume=26|issue=9|pages=1342–1347|doi=10.1002/ptr.3721|pmid=22294283|s2cid=34663821|issn=0951-418X}}</ref> sucrase and maltase.<ref>{{Cite journal|last1=Patel|first1=Mayurkumar B.|last2=Mishra|first2=Shrihari M.|date=January 2012|title=Magnoflorine from Tinospora cordifolia stem inhibits α-glucosidase and is antiglycemic in rats|journal=Journal of Functional Foods|volume=4|issue=1|pages=79–86|doi=10.1016/j.jff.2011.08.002|issn=1756-4646|doi-access=free}}</ref> In vivo research showed that palmatine reduced serum total cholesterol (TC) and triglycerides (TG) and increased serum high-density lipoprotein cholesterol.<ref>{{Cite journal|last1=Ma|first1=Hang|last2=Hu|first2=Yinran|last3=Zou|first3=Zongyao|last4=Feng|first4=Min|last5=Ye|first5=Xiaoli|last6=Li|first6=Xuegang|date=2016-04-04|title=Antihyperglycemia and Antihyperlipidemia Effect of Protoberberine Alkaloids From Rhizoma Coptidis in HepG2 Cell and Diabetic KK-Ay Mice|journal=Drug Development Research|volume=77|issue=4|pages=163–170|doi=10.1002/ddr.21302|pmid=27045983|s2cid=31823923|issn=0272-4391}}</ref>
=== Anticancer activity === Research showed that palmatine had broad anti-cancer activity. Palmatine had significant growth inhibitory effects on seven human cancer cell lines: 7701QGY, SMMC7721, HepG2, CEM, CEM/VCR, K III and Lewis.<ref>{{Cite journal|last1=Zhang|first1=Lei|last2=Li|first2=Jingjing|last3=Ma|first3=Fei|last4=Yao|first4=Shining|last5=Li|first5=Naisan|last6=Wang|first6=Jing|last7=Wang|first7=Yongbin|last8=Wang|first8=Xiuzhen|last9=Yao|first9=Qizheng|date=2012-09-25|title=Synthesis and Cytotoxicity Evaluation of 13-n-Alkyl Berberine and Palmatine Analogues as Anticancer Agents|journal=Molecules|volume=17|issue=10|pages=11294–11302|doi=10.3390/molecules171011294|pmid=23011273|pmc=6268624|issn=1420-3049|doi-access=free}}</ref> In addition, palmatine also had anti-cancer activity on MCF-7, U251, KB,<ref>{{Cite journal|last1=Costa|first1=Emmanoel Vilaça|last2=Cruz|first2=Pedro Ernesto O. da|last3=Pinheiro|first3=Maria Lúcia B.|last4=Marques|first4=Francisco A.|last5=Ruiz|first5=Ana Lúcia T. G.|last6=Marchetti|first6=Gabriela M.|last7=Carvalho|first7=João Ernesto de|last8=Barison|first8=Andersson|last9=Maia|first9=Beatriz Helena L. N. S.|date=2013|title=Aporphine and Tetrahydroprotoberberine Alkaloids from the Leaves ofGuatteria friesiana(Annonaceae) and their Cytotoxic Activities|journal=Journal of the Brazilian Chemical Society|doi=10.5935/0103-5053.20130103|issn=0103-5053|doi-access=free}}</ref> CHOK-1, HT-29 and SiHacell lines.<ref>{{Cite journal|last1=Bala|first1=Manju|last2=Pratap|first2=Kunal|last3=Verma|first3=Praveen Kumar|last4=Singh|first4=Bikram|last5=Padwad|first5=Yogendra|date=December 2015|title=Validation of ethnomedicinal potential of Tinospora cordifolia for anticancer and immunomodulatory activities and quantification of bioactive molecules by HPTLC|journal=Journal of Ethnopharmacology|volume=175|pages=131–137|doi=10.1016/j.jep.2015.08.001|pmid=26253577|issn=0378-8741}}</ref> Palmatine induced apoptosis in human skin epithelial carcinoma cells (A431) in a concentration- and time-dependent manner via damaging severely to DNA and inhibiting the activity of Bcl-2 protein.<ref>{{Cite journal|last1=Ali|first1=Daoud|last2=Ali|first2=Huma|date=2014-07-03|title=Assessment of DNA damage and cytotoxicity of palmatine on human skin epithelial carcinoma cells|journal=Toxicological & Environmental Chemistry|volume=96|issue=6|pages=941–950|doi=10.1080/02772248.2014.987510|bibcode=2014TxEC...96..941A |s2cid=84213943|issn=0277-2248}}</ref><ref>{{Cite journal|last1=Wu|first1=Juan|last2=Xiao|first2=Qicai|last3=Zhang|first3=Na|last4=Xue|first4=Changhu|last5=Leung|first5=Albert Wingnang|last6=Zhang|first6=Hongwei|last7=Tang|first7=Qing-Juan|last8=Xu|first8=Chuanshan|date=September 2016|title=Palmatine hydrochloride mediated photodynamic inactivation of breast cancer MCF-7 cells: Effectiveness and mechanism of action|journal=Photodiagnosis and Photodynamic Therapy|volume=15|pages=133–138|doi=10.1016/j.pdpdt.2016.07.006|pmid=27444887|issn=1572-1000}}</ref><ref>{{Cite journal|last1=He|first1=Qiyuan|last2=Zhang|first2=Hua|date=2020|title=Towards the Scalable vdW Heterostructure Array|journal=Acta Physico-Chimica Sinica|pages=2003075–0| doi=10.3866/pku.whxb202003075|issn=1000-6818|doi-access=free}}</ref> In addition, palmatine can inhibit the proliferation and infiltration of cancer cells.
=== Antibacterial and antiviral activity === Palmitine has inhibitory effect on Gram-positive bacteria which is significantly stronger than that on Gram-negative bacteria,<ref>{{Cite journal|last1=Deng|first1=Yecheng|last2=Zhang|first2=Ming|last3=Luo|first3=Haiyu|date=May 2012|title=Identification and antimicrobial activity of two alkaloids from traditional Chinese medicinal plant Tinospora capillipes|journal=Industrial Crops and Products|volume=37|issue=1|pages=298–302|doi=10.1016/j.indcrop.2011.12.006|issn=0926-6690}}</ref> and 9-O-substituted palmatine derivatives exhibited stronger antibacterial activity.<ref>{{Cite journal|last1=Li|first1=ZC|last2=Kong|first2=XB|last3=Mai|first3=WP|last4=Sun|first4=GC|last5=Zhao|first5=SZ|date=2015|title=Synthesis and antimicrobial activity of 9-o-substituted palmatine derivatives|url= |journal=Indian Journal of Pharmaceutical Sciences|volume=77|issue=2|pages=196–201|doi=10.4103/0250-474x.156588|pmid=26009653|issn=0250-474X|pmc=4442469 |doi-access=free }}</ref><ref>{{Cite journal|last1=Song|first1=Li|last2=Zhang|first2=Hai-Jing|last3=Deng|first3=An-Jun|last4=Li|first4=Jia|last5=Li|first5=Xiang|last6=Li|first6=Zhi-Hong|last7=Zhang|first7=Zhi-Hui|last8=Wu|first8=Lian-Qiu|last9=Wang|first9=Sheng-Qi|last10=Qin|first10=Hai-Lin|date=May 2018|title=Syntheses and structure-activity relationships on antibacterial and anti-ulcerative colitis properties of quaternary 13-substituted palmatines and 8-oxo-13-substituted dihydropalmatines|journal=Bioorganic & Medicinal Chemistry|volume=26|issue=9|pages=2586–2598|doi=10.1016/j.bmc.2018.04.025|pmid=29680749|issn=0968-0896}}</ref>
=== Anti-inflammatory activity === Studies have shown that palmatine can decrease the production of pro-inflammatory factors and increase the production of anti-inflammatory factors.<ref>{{Cite journal|last1=Yan|first1=Baoqi|last2=Wang|first2=Dongsheng|last3=Dong|first3=Shuwei|last4=Cheng|first4=Zhangrui|last5=Na|first5=Lidong|last6=Sang|first6=Mengqi|last7=Yang|first7=Hongzao|last8=Yang|first8=Zhiqiang|last9=Zhang|first9=Shidong|last10=Yan|first10=Zuoting|date=April 2017|title=Palmatine inhibits TRIF-dependent NF-κB pathway against inflammation induced by LPS in goat endometrial epithelial cells|journal=International Immunopharmacology|volume=45|pages=194–200|doi=10.1016/j.intimp.2017.02.004|pmid=28236763|s2cid=29087348|issn=1567-5769}}</ref>
=== Other pharmacological activity === Studies have shown that palmatine chave antioxidant activity,<ref>{{Cite journal|last1=Ma|first1=Bingxin|last2=Zhu|first2=Ling|last3=Zang|first3=Xiaoyan|last4=Chen|first4=Yuxin|last5=Li|first5=Dong|last6=Wang|first6=Youwei|date=October 2013|title=Coptis chinensis inflorescence and its main alkaloids protect against ultraviolet-B-induced oxidative damage|journal=Journal of Functional Foods|volume=5|issue=4|pages=1665–1672|doi=10.1016/j.jff.2013.07.010|issn=1756-4646}}</ref><ref>{{Cite journal|last1=Shia|first1=Chi-Sheng|last2=Hou|first2=Yu-Chi|last3=Juang|first3=Shin-Hun|last4=Tsai|first4=Shang-Yuan|last5=Hsieh|first5=Pei-Hsun|last6=Ho|first6=Lu-Ching|last7=Chao|first7=Pei-Dawn Lee|date=2011|title=Metabolism and Pharmacokinetics of San-Huang-Xie-Xin-Tang, a Polyphenol-Rich Chinese Medicine Formula, in Rats andEx-VivoAntioxidant Activity|journal=Evidence-Based Complementary and Alternative Medicine|volume=2011|page=721293|doi=10.1093/ecam/nep124|pmid=19737807|pmc=3137274|issn=1741-427X|doi-access=free}}</ref> had a protective effect on gastric ulcer,<ref>{{Cite journal|last1=Wang|first1=Wei-Min|last2=Nwabueze|first2=OkechukwuPatrick|last3=Yang|first3=Hui|last4=Zhai|first4=Hong-Bin|date=2018|title=High-performance liquid chromatography identification of gastroprotective and antioxidant effects of purified fractions A-E from the stem of Coscinium fenestratum|journal=Pharmacognosy Magazine|volume=14|issue=55|page=78|doi=10.4103/pm.pm_267_17|s2cid=103671390|issn=0973-1296 |doi-access=free }}</ref> derivatives of palmatine were more effective against ulcerative colitis, including low cytotoxicity to intestinal epithelial cells.<ref>{{Cite journal|last1=Song|first1=Li|last2=Zhang|first2=Hai-Jing|last3=Deng|first3=An-Jun|last4=Li|first4=Jia|last5=Li|first5=Xiang|last6=Li|first6=Zhi-Hong|last7=Zhang|first7=Zhi-Hui|last8=Wu|first8=Lian-Qiu|last9=Wang|first9=Sheng-Qi|last10=Qin|first10=Hai-Lin|date=May 2018|title=Syntheses and structure-activity relationships on antibacterial and anti-ulcerative colitis properties of quaternary 13-substituted palmatines and 8-oxo-13-substituted dihydropalmatines|journal=Bioorganic & Medicinal Chemistry|volume=26|issue=9|pages=2586–2598|doi=10.1016/j.bmc.2018.04.025|pmid=29680749|issn=0968-0896}}</ref> In addition, palmatine might have the antiarrhythmic effect,<ref>{{Cite journal|last1=Guo|first1=Rui|last2=Zhang|first2=Xiaoxiao|last3=Su|first3=Jin|last4=Xu|first4=Haiyu|last5=Zhang|first5=Yanqiong|last6=Zhang|first6=Fangbo|last7=Li|first7=Defeng|last8=Zhang|first8=Yi|last9=Xiao|first9=Xuefeng|last10=Ma|first10=Shuangcheng|last11=Yang|first11=Hongjun|date=May 2018|title=Identifying potential quality markers of Xin-Su-Ning capsules acting on arrhythmia by integrating UHPLC-LTQ-Orbitrap, ADME prediction and network target analysis|journal=Phytomedicine|volume=44|pages=117–128|doi=10.1016/j.phymed.2018.01.019|pmid=29526583|issn=0944-7113}}</ref> and provideprotection from myocardial ischemia-reperfusion injury.<ref>{{Cite journal|last1=Tan|first1=Hui-Li|last2=Chan|first2=Kok-Gan|last3=Pusparajah|first3=Priyia|last4=Duangjai|first4=Acharaporn|last5=Saokaew|first5=Surasak|last6=Mehmood Khan|first6=Tahir|last7=Lee|first7=Learn-Han|last8=Goh|first8=Bey-Hing|date=2016-10-07|title=Rhizoma Coptidis: A Potential Cardiovascular Protective Agent|journal=Frontiers in Pharmacology|volume=7|page=362|doi=10.3389/fphar.2016.00362|pmid=27774066|pmc=5054023|issn=1663-9812|doi-access=free}}</ref>
== Toxicity == A large number of studies have shown that palmatine has a complex effect on the metabolism of enzymes in the liver, and that palmatine has significant DNA toxicity.<ref>{{Cite journal|last1=Ali|first1=Daoud|last2=Ali|first2=Huma|date=2014-07-03|title=Assessment of DNA damage and cytotoxicity of palmatine on human skin epithelial carcinoma cells|journal=Toxicological & Environmental Chemistry|volume=96|issue=6|pages=941–950|doi=10.1080/02772248.2014.987510|bibcode=2014TxEC...96..941A |s2cid=84213943|issn=0277-2248}}</ref> However, some 9-O-substituted palmatine derivatives exhibited less toxic than palmatine.<ref>{{Cite journal|last1=Li|first1=ZC|last2=Kong|first2=XB|last3=Mai|first3=WP|last4=Sun|first4=GC|last5=Zhao|first5=SZ|date=2015|title=Synthesis and antimicrobial activity of 9-o-substituted palmatine derivatives|url= |journal=Indian Journal of Pharmaceutical Sciences|volume=77|issue=2|pages=196–201|doi=10.4103/0250-474x.156588|pmid=26009653|issn=0250-474X|pmc=4442469 |doi-access=free }}</ref> In addition, palmatine had higher affinity to nucleic acids than serum proteins, which make them suitable candidates for delivery by serum proteins.<ref>{{Cite journal|last1=Khan|first1=Asma Yasmeen|last2=Suresh Kumar|first2=Gopinatha|date=2015-12-01|title=Natural isoquinoline alkaloids: binding aspects to functional proteins, serum albumins, hemoglobin, and lysozyme|url= |journal=Biophysical Reviews|language=en|volume=7|issue=4|pages=407–420|doi=10.1007/s12551-015-0183-5|issn=1867-2469|pmc=5418488|pmid=28510102}}</ref>
==See also== * Berberine * Jatrorrhizine * Phellodendrine
==References== <references />
Category:Isoquinoline alkaloids Category:Quaternary ammonium compounds Category:Phenol ethers Category:Isoquinolinoisoquinolines Category:Methoxy compounds Category:Tetrahydroisoquinoline alkaloids Category:Acetylcholinesterase inhibitors Category:Neurotoxins