New Use Agriculture and Natural Plant Products Program, Department of Plant Biology, Rutgers University, New Brunswick, NJ 08901, USA.
CAPES Foundation, Ministry of Education of Brazil, Brasilia 70.040-020, DF, Brazil.
Molecules. 2022 Oct 19;27(20):7057. doi: 10.3390/molecules27207057.
Catnip ( L.) is of scientific interest largely due to the production of nepetalactones, volatile iridoid terpenes with strong arthropod repellent activity. However, the plant can also produce other bioactive volatile iridoids, such as nepetalic acid (NA), nepetalactam (NT) and dihydronepetalactone (DHNL) that have not been studied extensively. Germplasm studies on plants that can produce such compounds are scarce. The present study evaluated the chemical diversity of catnip genotypes with a focus on NA, NT and DHNL. A total of 34 genotypes were harvested at different times over two years. The ethanolic extract of the plants was screened for iridoids by ultra-high-performance liquid chromatography/triple quadrupole mass spectrometry. CR9 × CR3 genotype had the highest value for biomass yield, while cultivar CR9 had the highest value for accumulated NA. Genotype UK.2 had the highest value for accumulated NT yield and CR5 had the highest value for accumulated DHNL. Overall, patented cultivars and elite selections performed better than other less studied genotypes. Harvest time influenced the accumulation of secondary metabolites differentially for the genotypes. This is the first germplasm study with a focus on these iridoid compounds, yet more studies are necessary as genotype characterization is essential for breeding and standardization of products for industry.
荆芥（L.）主要因其产生具有强烈节肢动物驱避活性的挥发性环烯醚萜类化合物——荆芥内酯而引起科学兴趣。然而，该植物还可以产生其他生物活性挥发性环烯醚萜类化合物，如尚未广泛研究的川陈皮素（NA）、荆芥内酯（NT）和去氢荆芥内酯（DHNL）。对能够产生此类化合物的植物进行种质研究很少。本研究评估了不同时间收获的 34 个荆芥基因型的化学多样性，重点研究了 NA、NT 和 DHNL。在两年内的不同时间共收获了 34 个基因型。通过超高效液相色谱/三重四极杆质谱对植物的乙醇提取物进行了环烯醚萜类化合物的筛选。CR9×CR3 基因型的生物量产量最高，而 CR9 品种的 NA 积累量最高。UK.2 基因型的 NT 产量积累最高，CR5 基因型的 DHNL 产量积累最高。总体而言，专利品种和精选品种的表现优于其他研究较少的基因型。收获时间对不同基因型次生代谢物的积累有不同的影响。这是首次针对这些环烯醚萜化合物进行的种质研究，但还需要进行更多的研究，因为对基因型的特征描述对于培育和为工业标准化产品是必不可少的。
