Research Progress on the Biosynthesis and Regulation of β-Ionone

Abstract

β-Ionone, a cyclic isoprenoid compound with significant biological functions, occupies a special position among plant secondary metabolites. This ketone compound composed of 13 carbon atoms not only imparts unique aromatic characteristics to plants but also exhibits extensive pharmacological activities, including but not limited to antibacterial, antiviral, antitumor effects, and lipid-lowering properties. In recent years, with the rapid development of molecular biology techniques, researchers have gained deeper insights into the biosynthetic pathways and regulatory mechanisms of β-ionone. This article systematically reviews the chemical properties, biological activities, biosynthetic pathways, and molecular regulation mechanisms of β-ionone while exploring the application prospects of genetic engineering technology in improving its production for theoretical reference in related fields.

1. Chemical Properties and Biological Activities of β-Ionone

1.1 Chemical Structure and Physical Properties β-Ionone (chemical formula C13H20O) is a ketonic compound with a monocyclic terpene skeleton whose systematic name is 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one. In nature, ionones exist in various isomers such as α-ionone and γ-ionone; these isomers differ mainly in their double bond positions. Physically speaking, at room temperature β-ionone appears as a pale yellow to yellow liquid with typical violet floral aroma. Its molecular weight is 192.30 g/mol exhibiting typical lipophilic characteristics; it is insoluble in water or glycerol but soluble in most oils and alcohol solvents.

1.2 Biological Activity and Function β-Ionone demonstrates multifaceted biological activity making it valuable across pharmaceutical applications as well as agriculture and food industries. In medicine specifically，it shows significant anticancer activity by inhibiting cell proliferation through regulating HMG-CoA reductase activity among other mechanisms across multiple cancer models like liver cancer，lung cancer，and breast cancer demonstrating promising preventive effects along with therapeutic potential。Additionally，its strong antioxidant capacity allows effective scavenging free radicals protecting cells from oxidative damage。 In agriculture，β-ionones can be utilized as insect pheromones for pest control。By leveraging its unique volatile features environmentally friendly insect traps can be developed reducing reliance on chemical pesticides。在食品和化妆品工业中，由于其独特的芳香特性而被广泛用作香料添加剂。同时，它还是合成视黄酸、视黄醇、β-胡萝卜素和维生素A等重要化合物的前体物质。

2.Biosynthetic Pathways for β-Ionones

**2 .1 Metabolism Of Precursor Substances ** n The biosynthesis Of b -ionons begins With carotenoid metabolism pathway . Carotenoids serve As important photosynthetic pigments And antioxidants abundant within Photosynthetic organs . These tetraterpenoids undergo oxidative cleavage via carotenoid cleavage dioxygenases (CCDs) generating various apocarotenoids ,including b -ionons.This cleavage process displays high positional specificity where different CCD enzyme family members exhibit varying substrate preferences And cleavage site selectivity. n **2 .2 Key Enzymes & Genes ** Currently several key enzyme genes involved In b -ionons synthesis have been identified.The expression patterns Of these CCD enzyme genes display tissue-specificity closely associated With spatiotemporal accumulation Of b -ionons.Research indicates that CCD1 And CCD4 subfamily members play major roles during this synthesis process.These enzymes recognize specific carotenoid substrates such As beta-carotene cleaving them At particular double bond locations.Notably,the participating CCD enzymes’ evolutionary origins And functional differentiation may vary between different plant species providing A molecular basis For understanding species-specificity regarding b -ionons synthesis. n ###3.Molecular Regulation On Synthesis Of B – Ionones n 3 .1 Transcriptional Level Control ** The synthesis OF B – ionones Is finely regulated Across multiple levels.At transcriptional level,several families OF transcription factors participate IN regulating gene expressions OF ccd enzymes.WRKY ,MYB,NAC AND MADS family members activate Or inhibit ccd gene transcription By binding To specific cis-regulatory elements responding TO diverse internal/external signals Such AS light,hormonal cues environmental stresses thus coupling Their syntheses WITH growth/development processes adapting To environments conditions. n 3 .2 Epigenetic Regulations Recent studies show epigenetic Mechanisms play crucial roles Within regulating B–Ionones syntheses.Chromatin accessibility changes,DNA methylation modifications histONE modifications might all influence Expression activites FOR corresponding ccd Gene markers.With advancements Like ATAC-seq High-throughput sequencing technologies allow Researchers better understand relationships Between those epigenetic markers Synthesized Networks concerning Production strategies toward Future optimization efforts further elucidating Regulatory frameworks surrounding It’s metabolic profiles! N ###4.Applications Using Genetic Engineering Techniques Toward Producing Beta IONONES: N * 4.Metabolic Engineering Strategies: Utilizing genetic engineering approaches aimed Improving yields From Beta Ionines Has become hot research topic.In Plant systems over-expressing critical CDD Enzyme Genes Or silencing competing pathway Genes Via RNA interference(RNAi) methods could regulate Syntheses Effectively.CRISPR/Cas9 genome editing Technologies provide robust tools enabling precise Modifications enhancing yield potentials!These techniques apply both Functional Investigations Alongside creation Novel High-yielding Plant materials! N * 4.Heterologous Expression Systems: Microbial heterologous expression platforms offer alternative solutions Industrial-scale productions Through successful reconstruction Routes within E.coli Yeast strains optimizing precursor supplies Enhancing Key Enzyme Activities Cell Factory performance significantly boosting overall output!Future endeavors combining Systematic Biology Synthetic Approaches should aim optimize Metabolic networks improve regulatory components achieving efficient Biomanufacturing processes Yield improvements reaching unprecedented heights!!! N ###5.Future Prospects While Significant progress has been made Regarding Understanding Mechanisms underlying beta ionine Productions many Scientific questions remain unresolved.Firstly Molecular mechanism governing Regulatory dynamics under differing Environmental Conditions still warrant thorough investigations.Additionally Transport Storage Mechanisms Inside Plants need clarifying too.Furthermore Exploring Multi-gene Synergistic Controls Could breakthrough Achieving substantial Yield increases represents vital directions ahead.As Omics Technologies Gene Editing continue evolving expect Comprehensive Insights Into Biological Significance Leading Developments Higher efficiency Bio-production Techniques shortly!! N ###References [Relevant references should be listed here since original text did not provide any citation information hence omitted]