Biotechnological Exploration of Transformed Root Culture for Value-Added Products

Hairy roots are useful tools for studying the biosynthesis of different plant-derived valuable compounds.Hairy could be preferred hosts when desired compounds mainly accumulate in roots.Hairy being considered as an alternative system to microbial hosts, including Escherichia coli and Saccharomyces cerevisiae, producing natural secondary metabolites because they more similar native host plant.Hairy have emerged rapid characterization plant gene function enzyme activity vivo hairy naturally maintain many cofactors precusor substrates, encoded protein is likely properly folded compared with microbes. Medicinal plants produce anticancer, analgesic, anticholinergic or other activities, but low metabolite levels limited available tissue restrict yields. Transformed root cultures, also called roots, provide a feasible approach metabolites. Various strategies been used enhance production increasing substrate availability, regulating key biosynthetic genes, multigene engineering, combining genetic engineering elicitation, using transcription factors (TFs), introducing new genes. In this review, we focus on recent developments from medicinal plants, techniques boost metabolites, development technologies study these We discuss trends, emerging applications, future perspectives. numerous functionally diverse (see Glossary), terpenoids, phenylpropanoids, alkaloids. Many great pharmaceutical importance. For instance, some alkaloids anticancer (i.e., camptothecin, taxol, vinblastine), analgesic morphine codeine), properties atropine scopolamine) [1.Carqueijeiro I. et al.Beyond semi-synthetic artemisinin: metabolic anti-cancer drugs.Curr. Opin. Biotechnol. 2020; 65: 17-24Crossref PubMed Scopus (23) Google Scholar, 2.Li F.S. Weng J.K. Demystifying traditional herbal medicine modern approaches.Nat. 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Prog. 26: 1145-1153PubMed Scholar]RheinPolygonum multiflorumR1601LeafMS[93.Huang B. al.Optimal inductive cultural conditions Polygonum multiflorum mediated Agrobacterium rhizogenes R1601 anthraquinone constituents.Pharmacogn. Mag. 77-82Crossref (11) Scholar]ScutellarinErigeron breviscapusC58C1LeafB5[94.Chen al.Integrated transcript reveal EbCHI plays role scutellarin Erigeron breviscapus roots.Front. 9: 789Crossref (5) Scholar]SalidrosideRhodiola crenulataC58C1Leaf1/2MS[95.Lan X. al.Engineering salidroside Rhodiola crenulata tyrosine decarboxylase.PLoS ONE. 8e75459Crossref (41) Scholar]GinsenosidePanax ginsengA4Root1/2MS[96.Zhang al.Enhancement Rg1 overexpressing ?-L-rhamnosidase Bifidobacterium breve.Biotechnol. Lett. 37: 2091-2096Crossref (20) Scholar]ParthenolideTanacetum partheniumATCC15834LeafMS[97.Pourianezhad al.Effects parthenolide (TpPTS) Tanacetum parthenium culture.Plant 211-218Crossref (7) Scholar]Chicoric acidEchinacea purpureaR15834LeafWPM[98.Salmanzadeh al.Heterologous phosphatase limitation substantial chicoric Echinacea purpurea roots.Planta. 251: 31Crossref (6) Scholar]Farnesiferol BFerula pseudalliaceaATCC15834Leaf1/2MS[99.Khazaei induction farnesiferol B endemic Ferula pseudalliacea.3 Biotech. 407Crossref Scholar]RishitinSolanum tuberosumATCC15834TuberMS[100.Komaraiah al.Enhanced lipoxygenase elicitor-treated Solanum tuberosum.Biotechnol. 593-597Crossref (38) Scholar]Flavonoids/IsoflavonoidsGlycine maxARqual1Cotyledon, hypocotylsB5[101.Han al.GmMYB58 GmMYB205 seed-specific activators isoflavonoid Glycine max.Plant 36: 1889-1902Crossref (14) Scholar]NicotineNicotiana tabacumATCC15834LeafB5[102.Zhao nicotine Nicotiana tabacum L.Plant Tissue Organ Cult. 121-129Crossref Scholar]GossypolGossypium hirsutumA4LeafB5[103.Verma P.C. al.Efficient gossypol hirsutum L.).Curr. Pharm. 691-700Crossref Scholar]Resistance pathogen infectionVitis viniferaA4StemMS[104.Meteier E. al.Overexpression VvSWEET4 Grapevine increases sugar transport contents enhances resistance Pythium irregulare, soilborne pathogen.Front. 884Crossref Scholar]a Abbreviations: medium. Open table tab metabolites) general precursors. availability factor affecting compound production. achieved manipulation substrates precursors, intermediate products, end products (Table 2). encoding geraniol 10-hydroxylase (G10H), (SLS), phenyllactate UDP-glycosyltransferase, manipulated pumila belladonna [44.Cui 45.Shi al.Targeted committed roots.Ind. Crop. 148: 112277Crossref 46.Qiu Overexpression valerendiene VDS Valeriana officinalis resulted 1.5–4-fold sesquiterpenoid valerenic control [47.Ricigliano V. al.Regulation elicited roots.Phytochemistry. 125: 43-53Crossref Co-introduction DXS (encoding 1-deoxy-D-xylulose-5-phosphate synthase, pathway), GGPPS geranylgeranyl diphosphate middle provides diterpenoid production) yielded high 12.93 DW, 0.61 [48.Shi diterpene bioactivity engineering.J. Agric. 64: 2523-2530Crossref (74) This finding suggests crosstalk exists A strategy phenylpropanoid [49.Xiao c4h, tat, hppr hppd prompted rosmarinic cultures.PLoS 6e29713Crossref (99) Scholar].Table 2Examples Metabolicall