Recent Progress in Isolating and Purifying Amide Alkaloids from their
Natural Habitats: A Review

Himanchal      Sharma; Divya      Pathak; Sachin      Kumar
Abstract

Alkaloids are nitrogen-containing chemical compounds found in nature. Many alkaloids are heterocyclic in nature. They are nitrogen-based organic compounds with the nitrogen atoms enclosed in a heterocyclic ring. The chemical "pro alkaloid" is derived from the alkyl amines in it. Many ancient people, long before the advent of organic chemistry, recognized that many of these substances have measurable effects on the body's physiological functions. Alkaloids are a type of natural substances that are classified as secondary metabolites. Many different types of organisms create alkaloids, which are a class of natural products. Alkaloids showed antifungal, local anesthetic, anti-inflammatory, anticancer, analgesic, neuropharmacologic, antimicrobial, and many other activities. Amines, as opposed to alkaloids, are the more common classification for naturally occurring compounds that contain nitrogen in the exocyclic position (such as mescaline, serotonin, and dopamine). An amide molecule has a nitrogen atom that is chemically bound to a carbon atom in the carbonyl group. The -oic acid ending of the corresponding carboxylic acid is converted to -amide to form the correct nomenclature for an amide. This article offers an overview of numerous techniques for extracting, separating, and purifying alkaloids for use in natural medicine.
[1]
Kurek, J. Introductory Chapter: Alkaloids - their importance in nature and for human life. In: Alkaloids - Their Importance in Nature and Human Life; ntechOpen, 2019. 

[2]
Dey, P.; Kundu, A.; Kumar, A.; Gupta, M.; Lee, B.M.; Bhakta, T.; Dash, S.; Kim, H.S. Analysis of alkaloids (indole alkaloids, isoquinoline alkaloids, tropane alkaloids). In: Recent Advances in Natural Products Analysis; Elsevier, 2020; pp. 505-567.
 [http://dx.doi.org/10.1016/B978-0-12-816455-6.00015-9]

[3]
Thawabteh, A.; Juma, S.; Bader, M.; Karaman, D.; Scrano, L.; Bufo, S.; Karaman, R. The biological activity of natural alkaloids against herbivores, cancerous cells and pathogens. Toxins,  2019, 11(11), 656.
 [http://dx.doi.org/10.3390/toxins11110656] [PMID:  31717922]

[4]
Ji, Y; Yu, M; Wang, B; Zhang, Y The extraction, separation and purification of alkaloids in the natural medicine. J. Chem. Pharmaceut. Res.,  2014, 6(1), 338-345.

[5]
Dai, J.C.; Maalouf, N.M.; Hill, K.; Antonelli, J.A.; Pearle, M.S.; Johnson, B.A. Alkali citrate content of common over-the-counter and medical food supplements. J. Endourol.,  2023, 37(1), 112-118.
 [http://dx.doi.org/10.1089/end.2022.0274] [PMID:  35972746]

[6]
Bardasov, I.N.; Ievlev, M.Y. 12.01 - Bicyclic 6-6 systems with one bridgehead (ring junction) nitrogen atom: no extra heteroatom; Elsevier: Oxford, 2022, pp. 1-61.

[7]
Bhambhani, S.; Kondhare, K.R.; Giri, A.P. Diversity in chemical structures and biological properties of plant alkaloids. Molecules,  2021, 26(11), 3374.
 [http://dx.doi.org/10.3390/molecules26113374] [PMID:  34204857]

[8]
Hussein, R.A.; El-Anssary, A.A. Plants secondary metabolites: The key drivers of the pharmacological actions of medicinal plants. In: Herbal Medicine; IntechOpen, 2018. 

[9]
Nguyen, T.D.; Dang, T.T.T. Cytochrome P450 enzymes as key drivers of alkaloid chemical diversification in plants. Front. Plant Sci.,  2021, 12, 682181.
 [http://dx.doi.org/10.3389/fpls.2021.682181]

[10]
Eguchi, R.; Ono, N.; Hirai Morita, A.; Katsuragi, T.; Nakamura, S.; Huang, M.; Altaf-Ul-Amin, M.; Kanaya, S. Classification of alkaloids according to the starting substances of their biosynthetic pathways using graph convolutional neural networks. BMC Bioinformatics,  2019, 20(1), 380.
 [http://dx.doi.org/10.1186/s12859-019-2963-6] [PMID:  31288752]

[11]
Rajput, A.; Sharma, R.; Bharti, R. Pharmacological activities and toxicities of alkaloids on human health. Mater. Today Proc.,  2022, 48, 1407-1415.
 [http://dx.doi.org/10.1016/j.matpr.2021.09.189]

[12]
Ncube, B.; Van Staden, J. Tilting plant metabolism for improved metabolite biosynthesis and enhanced human benefit. Molecules,  2015, 20(7), 12698-12731.
 [http://dx.doi.org/10.3390/molecules200712698] [PMID:  26184148]

[13]
Heinrich, M.; Mah, J.; Amirkia, V. Alkaloids used as medicines: structural phytochemistry meets biodiversity-An update and forward look. Molecules,  2021, 26(7), 1836.
 [http://dx.doi.org/10.3390/molecules26071836] [PMID:  33805869]

[14]
Plazas, E.; Avila, M. M.C.; Muñoz, D.R.; Cuca S, L.E. Natural isoquinoline alkaloids: Pharmacological features and multi-target potential for complex diseases. Pharmacol. Res.,  2022, 177(January), 106126.
 [http://dx.doi.org/10.1016/j.phrs.2022.106126] [PMID:  35151857]

[15]
Diamond, A.; Desgagne-Penix, I. Metabolic engineering for the production of plant isoquinoline alkaloids. Plant Biotechnol. J.,  2015, 14.
 [PMID:  26503307]

[16]
Kohnen-Johannsen, K.; Kayser, O. Tropane alkaloids: Chemistry, pharmacology, biosynthesis and production. Molecules,  2019, 24(4), 796.
 [http://dx.doi.org/10.3390/molecules24040796] [PMID:  30813289]

[17]
Nunes, C.R.; Barreto Arantes, M.; Menezes de Faria Pereira, S.; Leandro da Cruz, L.; de Souza Passos, M.; Pereira de Moraes, L.; Vieira, I.J.C.; Barros de Oliveira, D. Plants as sources of anti-inflammatory agents. Molecules,  2020, 25(16), 3726.
 [http://dx.doi.org/10.3390/molecules25163726] [PMID:  32824133]

[18]
Twaij, B.M.; Hasan, M.N. Bioactive secondary metabolites from plant sources: Types, synthesis, and their therapeutic uses. Int. J. Plant Biol.,  2022, 13(1), 4-14.
 [http://dx.doi.org/10.3390/ijpb13010003]

[19]
Umer, S.M.; Solangi, M.; Khan, K.M.; Saleem, R.S.Z. Indole-containing natural products 2019-2022: Isolations, reappraisals, syntheses, and biological activities. Molecules,  2022, 27(21), 7586.
 [http://dx.doi.org/10.3390/molecules27217586] [PMID:  36364413]

[20]
Abookleesh, F.L.; Al-Anzi, B.S.; Ullah, A. Potential antiviral action of alkaloids. Molecules,  2022, 27(3), 903.
 [http://dx.doi.org/10.3390/molecules27030903] [PMID:  35164173]

[21]
Atanasov, A.G.; Zotchev, S.B.; Dirsch, V.M.; Supuran, C.T.; Banach, M.; Rollinger, J.M. Natural products in drug discovery: Advances and opportunities. Nat. Rev. Drug Discov.,  2021, 20(3), 200-216.
 [http://dx.doi.org/10.1038/s41573-020-00114-z] [PMID:  33510482]

[22]
Ozyigit, I.I.; Dogan, I.; Hocaoglu-Ozyigit, A.; Yalcin, B.; Erdogan, A.; Yalcin, I.E.; Cabi, E.; Kaya, Y. Production of secondary metabolites using tissue culture-based biotechnological applications. Front. Plant Sci.,  2023, 14, 1132555.
 [http://dx.doi.org/10.3389/fpls.2023.1132555] [PMID:  37457343]

[23]
Riaz, M.; Khalid, R.; Afzal, M.; Anjum, F.; Fatima, H.; Zia, S.; Rasool, G.; Egbuna, C.; Mtewa, A.G.; Uche, C.Z.; Aslam, M.A. Phytobioactive compounds as therapeutic agents for human diseases: A review. Food Sci. Nutr.,  2023, 11(6), 2500-2529.
 [http://dx.doi.org/10.1002/fsn3.3308] [PMID:  37324906]

[24]
Steiniger, K.A.; Lamb, M.C.; Lambert, T.H. Cross-coupling of amines via photocatalytic denitrogenation of in situ generated diazenes. J. Am. Chem. Soc.,  2023, 145(21), jacs.3c03634.
 [http://dx.doi.org/10.1021/jacs.3c03634] [PMID:  37201211]

[25]
Liu, L.; Simon, S.A. Similarities and differences in the currents activated by capsaicin, piperine, and zingerone in rat trigeminal ganglion cells. J. Neurophysiol.,  1996, 76(3), 1858-1869.
 [http://dx.doi.org/10.1152/jn.1996.76.3.1858] [PMID:  8890298]

[26]
Saraei, P.; Asadi, I.; Kakar, M.A.; Moradi-Kor, N. The beneficial effects of metformin on cancer prevention and therapy: A comprehensive review of recent advances. Cancer Manag. Res.,  2019, 11, 3295-3313.
 [http://dx.doi.org/10.2147/CMAR.S200059] [PMID:  31114366]

[27]
Ullah, A.; Munir, S.; Badshah, S.L.; Khan, N.; Ghani, L.; Poulson, B.G.; Emwas, A.H.; Jaremko, M. Important flavonoids and their role as a therapeutic agent. Molecules,  2020, 25(22), 5243.
 [http://dx.doi.org/10.3390/molecules25225243] [PMID:  33187049]

[28]
Preto, A.J.; Correia, P.C.; Moreira, I.S. DrugTax: Package for drug taxonomy identification and explainable feature extraction. J. Cheminform.,  2022, 14(1), 73.
 [http://dx.doi.org/10.1186/s13321-022-00649-w] [PMID:  36303244]

[29]
Qaderi, M.M.; Martel, A.B.; Strugnell, C.A. Environmental factors regulate plant secondary metabolites. Plants,  2023, 12(3), 447.
 [http://dx.doi.org/10.3390/plants12030447] [PMID:  36771531]

[30]
Elshafie, H.S.; Camele, I.; Mohamed, A.A. A comprehensive review on the biological, agricultural and pharmaceutical properties of secondary metabolites based-plant origin. Int. J. Mol. Sci.,  2023, 24(4), 3266.
 [http://dx.doi.org/10.3390/ijms24043266] [PMID:  36834673]

[31]
Jan, R.; Asaf, S.; Numan, M. Lubna; Kim, K-M. Plant secondary metabolite biosynthesis and transcriptional regulation in response to biotic and abiotic stress conditions. Agronomy,  2021, 11(5), 968.
 [http://dx.doi.org/10.3390/agronomy11050968]

[32]
Jamloki, A.; Bhattacharyya, M.; Nautiyal, M.C.; Patni, B. Elucidating the relevance of high temperature and elevated CO2 in plant secondary metabolites (PSMs) production. Heliyon,  2021, 7(8), e07709.
 [http://dx.doi.org/10.1016/j.heliyon.2021.e07709] [PMID:  34430728]

[33]
Butnariu, M.; Quispe, C.; Herrera-Bravo, J.; Pentea, M.; Sarac, I.; Küşümler, A.S. Papaver plants: Current insights on phytochemical and nutritional composition along with biotechnological applications. Oxid. Med. Cell. Longev.,  2022, 2022, 2041769.

[34]
Chowański, S.; Adamski, Z.; Marciniak, P.; Rosiński, G.; Büyükgüzel, E.; Büyükgüzel, K.; Falabella, P.; Scrano, L.; Ventrella, E.; Lelario, F.; Bufo, S. A review of bioinsecticidal activity of solanaceae alkaloids. Toxins,  2016, 8(3), 60.
 [http://dx.doi.org/10.3390/toxins8030060] [PMID:  26938561]

[35]
Tlak Gajger, I.; Dar, S.A. Plant allelochemicals as sources of insecticides. Insects,  2021, 12(3), 189.
 [http://dx.doi.org/10.3390/insects12030189] [PMID:  33668349]

[36]
Guerre, P. Ergot alkaloids produced by endophytic fungi of the genus Epichloë. Toxins,  2015, 7(3), 773-790.
 [http://dx.doi.org/10.3390/toxins7030773] [PMID:  25756954]

[37]
Kurek, J. Cytotoxic colchicine alkaloids: From plants to drugs. In: Cytotoxicity; IntechOpen, 2018. 
 [http://dx.doi.org/10.5772/intechopen.72622]

[38]
Dhyani, P.; Quispe, C.; Sharma, E.; Bahukhandi, A.; Sati, P.; Attri, D.C.; Szopa, A.; Sharifi-Rad, J.; Docea, A.O.; Mardare, I.; Calina, D.; Cho, W.C. Anticancer potential of alkaloids: A key emphasis to colchicine, vinblastine, vincristine, vindesine, vinorelbine and vincamine. Cancer Cell Int.,  2022, 22(1), 206.
 [http://dx.doi.org/10.1186/s12935-022-02624-9] [PMID:  35655306]

[39]
Sayhan, H.; Beyaz, S.G.; Çeliktaş, A. The local anesthetic and pain relief activity of alkaloids. In: Alkaloids - Alternatives in Synthesis, Modification and Application; IntechOpen, 2017. 
 [http://dx.doi.org/10.5772/intechopen.69847]

[40]
Adamski, Z.; Blythe, L.L.; Milella, L.; Bufo, S.A. Biological activities of alkaloids: From toxicology to pharmacology. Toxins,  2020, 12(4), 210.
 [http://dx.doi.org/10.3390/toxins12040210] [PMID:  32224853]

[41]
He, Y.; Chen, Z.; Qu, H.; Gong, X. Research progress on the separation of alkaloids from chinese medicines by column chromatography. Adv. Chem. Eng. Sci.,  2020, 10(4), 358-377.
 [http://dx.doi.org/10.4236/aces.2020.104023]

[42]
Acikara, O.B. Ion-exchange chromatography and its applications. In: Column Chromatography; IntechOpen, 2013. 

[43]
Kumar, S.; Jain, S. History, introduction, and kinetics of ion exchange materials. J. Chem.,  2013, 2013, 957647.

[44]
Shams, K.A.; Nazif, N.M.; Abdel Azim, N.S.; Abdel Shafeek, K.A.; El-Missiry, M.M.; Ismail, S.I.; Seif El Nasr, M.M. Isolation and characterization of antineoplastic alkaloids from Catharanthus roseus L. Don. cultivated in Egypt. Afr. J. Tradit. Complement. Altern. Med.,  2009, 6(2), 118-122.
 [PMID:  20209002]

[45]
Zhang, Q.W.; Lin, L.G.; Ye, W.C. Techniques for extraction and isolation of natural products: A comprehensive review. Chin. Med.,  2018, 13(1), 20.
 [http://dx.doi.org/10.1186/s13020-018-0177-x] [PMID:  29692864]

[46]
Chen, J.; Ma, X.; Gao, K.; Wang, Y.; Zhao, H.; Wu, H.; Wang, J.; Xie, H.; OuYang, Y.; Luo, L.; Guo, S.; Han, J.; Liu, B.; Wang, W. The active ingredients of Jiang-Zhi-Ning: Study of the Nelumbo nucifera alkaloids and their main bioactive metabolites. Molecules,  2012, 17(8), 9855-9867.
 [http://dx.doi.org/10.3390/molecules17089855] [PMID:  22898740]

[47]
Liu, Q.; Li, X.; Li, C.; Zheng, Y.; Peng, G. 1-deoxynojirimycin alleviates insulin resistance via activation of insulin signaling PI3K/AKT pathway in skeletal muscle of db/db mice. Molecules,  2015, 20(12), 21700-21714.
 [http://dx.doi.org/10.3390/molecules201219794] [PMID:  26690098]

[48]
Couper, J.R.; Penney, W.R.; Fair, J.R.; Walas, S.M. 15 - Adsorption and ion exchange. In: Chemical Process Equipment; Gulf Professional Publishing, 2010. 

[49]
Dragull, K.; Beck, J.J. Isolation of natural products by ion-exchange methods. Methods Mol. Biol.,  2012, 864, 189-219.
 [http://dx.doi.org/10.1007/978-1-61779-624-1_8] [PMID:  22367898]

[50]
Pismenskaya, N.; Sarapulova, V.; Klevtsova, A.; Mikhaylin, S.; Bazinet, L. Adsorption of anthocyanins by cation and anion exchange resins with aromatic and aliphatic polymer matrices. Int. J. Mol. Sci.,  2020, 21(21), 7874.
 [http://dx.doi.org/10.3390/ijms21217874] [PMID:  33114195]

[51]
Akram, M.N.; Verpoorte, R.; Pomahačová, B. Methods for the analysis of galanthamine and its extraction from laboratory to industrial scale. S. Afr. J. Bot.,  2021, 136, 51-64.
 [http://dx.doi.org/10.1016/j.sajb.2020.08.004]

[52]
Li, Q.; Xu, J.; Yang, L.; Zhou, X.; Cai, Y.; Zhang, Y. Transcriptome analysis of different tissues reveals key genes associated with galanthamine biosynthesis in lycoris longituba. Front. Plant Sci.,  2020, 11, 519752.
 [http://dx.doi.org/10.3389/fpls.2020.519752] [PMID:  33042169]

[53]
Feng, W.; Li, M.; Hao, Z.; Zhang, J. Analytical methods of isolation and identification. In: Phytochemicals in Human Health; IntechOpen, 2019. 

[54]
Ajanal, M.; Gundkalle, M.; Nayak, S. Estimation of total alkaloid in Chitrakadivati by UV-Spectrophotometer. Anc. Sci. Life,  2012, 31(4), 198-201.
 [http://dx.doi.org/10.4103/0257-7941.107361] [PMID:  23661869]

[55]
Tang, J.; Liang, S.; Dong, B.; Li, Y.; Yao, S. Extraction and quantitative analysis of tropane alkaloids in Radix physochlainae by emulsion liquid membrane with tropine-based ionic liquid. J. Chromatogr. A,  2019, 1583, 9-18.
 [http://dx.doi.org/10.1016/j.chroma.2018.11.009] [PMID:  30429086]

[56]
Nguyen, N-VT; Nguyen, K-NH; Nguyen, KT; Kim, KH; Aboul-Enein, HY The impact of chirality on the analysis of alkaloids in plant. Pharmacia.,  2021, 68(3), 643-656.
 [http://dx.doi.org/10.3897/pharmacia.68.e71101]

[57]
Choi, Y.H.; Chin, Y.W.; Kim, J.; Jeon, S.H.; Yoo, K.P. Strategies for supercritical fluid extraction of hyoscyamine and scopolamine salts using basified modifiers. J. Chromatogr. A,  1999, 863(1), 47-55.
 [http://dx.doi.org/10.1016/S0021-9673(99)00962-0] [PMID:  10591463]

[58]
Akhgari, A.; Laakso, I.; Seppänen-Laakso, T.; Yrjönen, T.; Vuorela, H.; Oksman-Caldentey, K.M.; Rischer, H. Analysis of indole alkaloids from Rhazya stricta hairy roots by ultra-performance liquid chromatography-mass spectrometry. Molecules,  2015, 20(12), 22621-22634.
 [http://dx.doi.org/10.3390/molecules201219873] [PMID:  26694342]

[59]
Wei, X.; Shen, H.; Wang, L.; Meng, Q.; Liu, W. Analyses of total alkaloid extract of Corydalis yanhusuo by comprehensive RP × RP liquid chromatography with pH difference. J. Anal. Methods Chem.,  2016, 2016, 9752735.

[60]
Bastida, J.; Lavilla, R.; Viladomat, F. Chemical and biological aspects of Narcissus alkaloids. Alkaloids Chem. Biol.,  2006, 63, 87-179.
 [http://dx.doi.org/10.1016/S1099-4831(06)63003-4] [PMID:  17133715]

[61]
Morrow, G.W. Biosynthesis of alkaloids and related compounds. In: Bioorganic Synthesis: An Introduction; Oxford University Press, 2016. 

[62]
Yin, X.; Ma, K.; Dong, Y.; Dai, M. Pyrrole strategy for the γ-lactam-containing stemona alkaloids: (±)Stemoamide, (±)tuberostemoamide, and (±)sessilifoliamide A. Org. Lett.,  2020, 22(13), 5001-5004.
 [http://dx.doi.org/10.1021/acs.orglett.0c01570] [PMID:  32551684]

[63]
Xing, W.; Chen, L.; Zhang, F. Separation of camptothecin from Camptotheca acuminate samples using cloud point extraction. Anal. Methods,  2014, 6(11), 3644-3650.
 [http://dx.doi.org/10.1039/C3AY42289E]

[64]
Petruczynik, A. Analysis of alkaloids from different chemical groups by different liquid chromatography methods. Cent. Eur. J. Chem.,  2012, 10(3), 802-835.

[65]
Takeda, S.; Yajima, N.; Kitazato, K.; Unemi, N. Antitumor activities of harringtonine and homoharringtonine, cephalotaxus alkaloids which are active principles from plant by intraperitoneal and oral administration. J. Pharmacobiodyn.,  1982, 5(10), 841-847.
 [http://dx.doi.org/10.1248/bpb1978.5.841] [PMID:  7161711]

[66]
Abubakar, A.; Haque, M. Preparation of medicinal plants: Basic extraction and fractionation procedures for experimental purposes. J. Pharm. Bioallied Sci.,  2020, 12(1), 1-10.
 [http://dx.doi.org/10.4103/jpbs.JPBS_175_19] [PMID:  32801594]

[67]
Li, W.X.; Wang, H.; Dong, A.W. Systematic separation and purification of alkaloids from Euchresta tubulosa dunn. by various chromatographic methods. Processes,  2019, 7(12), 924.
 [http://dx.doi.org/10.3390/pr7120924]

[68]
Stéphane, F.F.Y. Extraction of bioactive compounds from medicinal plants and herbs. In: Natural Medicinal Plants; IntechOpen, 2021. 

[69]
Daley, S.; Cordell, G.A. Alkaloids in contemporary drug discovery to meet global disease needs. Molecules,  2021, 26(13), 3800.
 [http://dx.doi.org/10.3390/molecules26133800] [PMID:  34206470]

[70]
Dimitrijević, D.; Bösenhofer, M.; Harasek, M. Liquid-liquid phase separation of two non-dissolving liquids-A mini review. Processes,  2023, 11(4), 1145.
 [http://dx.doi.org/10.3390/pr11041145]

[71]
Iqbal, M.; Tao, Y.; Xie, S.; Zhu, Y.; Chen, D.; Wang, X.; Huang, L.; Peng, D.; Sattar, A.; Shabbir, M.A.B.; Hussain, H.I.; Ahmed, S.; Yuan, Z. Aqueous two-phase system (ATPS): An overview and advances in its applications. Biol. Proced. Online,  2016, 18(1), 18.
 [http://dx.doi.org/10.1186/s12575-016-0048-8] [PMID:  27807400]

[72]
Huang, X.; Ai, C.; Yao, H.; Zhao, C.; Xiang, C.; Hong, T.; Xiao, J. Guideline for the extraction, isolation, purification, and structural characterization of polysaccharides from natural resources. eFood,  2022, 3(6), e37.
 [http://dx.doi.org/10.1002/efd2.37]

[73]
Chaves, J.O.; de Souza, M.C.; da Silva, L.C.; Lachos-Perez, D.; Torres-Mayanga, P.C.; Machado, A.P.F.; Forster-Carneiro, T.; Vázquez-Espinosa, M.; González-de-Peredo, A.V.; Barbero, G.F.; Rostagno, M.A. Extraction of flavonoids from natural sources using modern techniques. Front Chem.,  2020, 8, 507887.
 [http://dx.doi.org/10.3389/fchem.2020.507887] [PMID:  33102442]

[74]
Sasidharan, S.; Chen, Y.; Saravanan, D.; Sundram, K.M.; Yoga Latha, L. Extraction, isolation and characterization of bioactive compounds from plants’ extracts. Afr. J. Tradit. Complement. Altern. Med.,  2011, 8(1), 1-10.
 [PMID:  22238476]

[75]
Usman, I.; Hussain, M.; Imran, A.; Afzaal, M.; Saeed, F.; Javed, M. Traditional and innovative approaches for the extraction of bioactive compounds. Int. J. Food Prop.,  2022, 25(1), 1215-1233.
 [http://dx.doi.org/10.1080/10942912.2022.2074030]

[76]
Tena, M.T. Extraction | pressurized liquid extraction. In: Worsfold P, Poole C, Townshend A, Miró MBT-E of AS; Third, E., Ed.; Academic Press: Oxford, 2019; pp. 78-83.

[77]
Bladergroen, M.R.; van der Burgt, Y.E.M. Solid-phase extraction strategies to surmount body fluid sample complexity in high-throughput mass spectrometry-based proteomics. J. Anal. Methods Chem.,  2015, 2015, 1-8.
 [http://dx.doi.org/10.1155/2015/250131] [PMID:  25692071]

[78]
Kostanyan, A.A.; Voshkin, A.A.; Belova, V.V. Analytical, preparative, and industrial-scale separation of substances by methods of countercurrent liquid-liquid chromatography. Molecules,  2020, 25(24), 6020.
 [http://dx.doi.org/10.3390/molecules25246020] [PMID:  33353256]

[79]
Stein, S. Isolation of natural proteins. Bioprocess Technol.,  1990, 7(3), 137-160.
 [PMID:  1370012]

[80]
Sharma, S.; Bhattacharya, A. Drinking water contamination and treatment techniques. Appl. Water Sci.,  2017, 7(3), 1043-1067.
 [http://dx.doi.org/10.1007/s13201-016-0455-7]

[81]
Tang, Y.Q.; Weng, N. Salting-out assisted liquid–liquid extraction for bioanalysis. Bioanalysis,  2013, 5(12), 1583-1598.
 [http://dx.doi.org/10.4155/bio.13.117] [PMID:  23795935]

[82]
Fu, C.; Li, Z.; Sun, Z.; Xie, S. A review of salting-out effect and sugaring-out effect: Driving forces for novel liquid-liquid extraction of biofuels and biochemicals. Front. Chem. Sci. Eng., 2020.

[83]
Yang, J.; Su, Y.; Luo, J.F.; Gu, W.; Niu, H.M.; Li, Y.; Wang, Y-H.; Long, C-L. New amide alkaloids from Piper longum fruits. Nat. Prod. Bioprospect.,  2013, 3(6), 277-281.
 [http://dx.doi.org/10.1007/s13659-013-0073-0]

[84]
Sun, X.; Li, C.; Ma, J.; Zang, Y.; Huang, J.; Chen, N.; Wang, X.; Zhang, D. New amide alkaloids and carbazole alkaloid from the stems of Clausena lansium. Fitoterapia,  2021, 154(July), 104999.
 [http://dx.doi.org/10.1016/j.fitote.2021.104999] [PMID:  34302918]

[85]
Xu, W.; Ying, Z.; Tao, X.; Ying, X.; Yang, G. Two new amide alkaloids from Portulaca oleracea L. and their anticholinesterase activities. Nat. Prod. Res.,  2020, 0(0), 1-7.
 [PMID:  32193952]

[86]
Lan, X.; Ying, Z.; Guo, S.; Duan, Y.; Cui, X.; Leng, A.; Ying, X. Two novel amide alkaloids from Portulaca oleracea L. and their anti-inflammatory activities. Nat. Prod. Res.,  2022, 36(21), 5567-5574.
 [http://dx.doi.org/10.1080/14786419.2021.2021519] [PMID:  34963386]

[87]
Long, Z.; Zhang, Y.; Guo, Z.; Wang, L.; Xue, X.; Zhang, X.; Wang, S.; Wang, Z.; Civelli, O.; Liang, X. Amide alkaloids from Scopolia tangutica. Planta Med.,  2014, 80(13), 1124-1130.
 [http://dx.doi.org/10.1055/s-0034-1382961] [PMID:  25127021]

[88]
Wen, H.; Li, Y.; Liu, X.; Ye, W.; Yao, X.; Che, Y. Fusagerins A-F, new alkaloids from the fungus fusarium sp. Nat. Prod. Bioprospect.,  2015, 5(4), 195-203.
 [http://dx.doi.org/10.1007/s13659-015-0067-1] [PMID:  26329590]

[89]
Huang, KP; Xu, LL; Li, S; Wei, YL; Yang, L; Hao, XJ Uncarialines A-E, new alkaloids from Uncaria rhynchophylla and their anticoagulant activity. Nat Prod Bioprosp.,  2023, 13(1), 8.
Cite As
Current Bioactive Compounds

Recent Progress in Isolating and Purifying Amide Alkaloids from their Natural Habitats: A Review

Abstract
