Caffeoylquinic acids (CQAs), a class of phenolic acid metabolites widely distributed in plants, encompass 15 positional isomers from mono- to tetra-esters, with 5-O-caffeoylquinic acid (5-CQA) as the predominant form. The biosynthesis of 5-CQA from phenylalanine proceeds through five primary pathways, which are finely regulated by environmental, hormonal, and transcription factors from families such as MYB, WRKY, and bHLH. These regulators control 5-CQA synthesis by binding specifically to the promoter regions of key structural genes, including PAL, 4CL and HCT/HQT. Subsequently, 5-CQA serves as a central precursor for the biosynthesis of other CQAs. In terms of bioactivity, CQAs possess remarkable pharmacological activities, encompassing antioxidant, antimicrobial, anti-diabetic, anti-inflammatory and anti-tumor properties. For instance, anti-inflammatory effects are demonstrated by the ability of 5-CQA to reduce key pro-inflammatory cytokines (e.g., TNF-α and IL-1β) and downregulate the TLR4/NF-κB pathway. The synergistic action of 5-CQA with ultraviolet-A reduced succinate-coenzyme Q reductase activity by approximately 72%, highlighting its potential to disrupt bacterial metabolism and combat antibiotic resistance. Furthermore, 3,4,5-triCQA exhibits potent anti-influenza virus activity, potentially through a mechanism distinct from existing neuraminidase inhibitors. Beyond medicine, CQAs show promise in light industry. They serve as antibiotic alternatives in livestock feed to enhance gut health, extend food shelf life through their antioxidant activity, and function as active ingredients in UV-protective skincare formulations. CQAs also enhance plant stress tolerance to cold, arsenic, and pests by mechanisms such as scavenging reactive oxygen species and inhibiting pest mobility. While this review consolidates progress in the biosynthesis and bioactivity of CQAs specifically with caffeoyl substituents, future efforts should leverage modern biotechnological tools and interdisciplinary approaches to bridge critical knowledge gaps in their biosynthesis, transport, and clinical translation.

Chrysanthemum morifolium ‘11-C-2’ is a variety of chrysanthemums with high ornamental and tea value, experiencing significant market demand. However, as cultivation areas expand, issues such as viral infection, germplasm degradation, low proliferation coefficient, and slow proliferation rate arise, necessitating the establishment of an efficient in vitro regeneration system. This study, based on the principles of orthogonal experimental design, explored the regeneration system of Chrysanthemum cultivar ‘11-C-2’ using sterile seedlings. The research focused on three key stages: adventitious bud differentiation, rooting culture, and acclimatization–transplantation, employing shoot-bearing stem segments and leaves as explants. The findings indicate that the optimal explant for the Chrysanthemum ‘11-C-2’ sterile seedlings is the shoot-bearing stem segment. The best medium for adventitious bud differentiation was determined to be MS supplemented with 1.5 mg/L 6-BA and 0.5 mg/L NAA. Bud differentiation began on day 17 with a 100% differentiation rate, completing around day 48. The maximum differentiation coefficient reached 87, with an average of 26.67. The adventitious buds were then cultured for rooting in the optimal medium of 1/2 MS supplemented with 0.1 mg/L NAA. Rooting was initiated on day 4 and was completed by day 14, achieving a rooting rate of 97.62%. After a 5-day acclimatization under natural light, the rooted seedlings were transplanted into a growth substrate with a peat-to-vermiculite ratio of 1:2. The plants exhibited optimal growth, with a transplantation survival rate of 100%. The findings provide data support for the efficient large-scale propagation of ‘11-C-2’ and lay the foundation for germplasm preservation and genetic transformation research of tea chrysanthemums.

With the intensification of global climate change and urbanization, extreme rainfall and urban flooding have become increasingly frequent, making the flood tolerance of garden plants a key issue in urban landscaping and ecology. Identifying research progress and development trends in the waterlogging tolerance of garden plants, as well as selecting waterlogging-tolerant species, is a core strategy for advancing urban ecological development. This study employed the Web of Science database to conduct a systematic search using subject, title, and keyword criteria. After excluding irrelevant studies through full-text reviews, 164 articles were selected. Using bibliometric analysis, the research systematically reviewed relevant literature published over the past 21 years on waterlogging tolerance in landscape plants, both domestically and internationally, analyzing research trends and hotspots, while summarizing the physiological and molecular responses of garden plants in flood-prone environments. The research indicates significant differences in flood tolerance among different species of garden plants. The main research directions include morphology, physiology, molecular biology, ecology, cultivation, and species selection, with molecular biology emerging as a key area of development in recent years. Furthermore, in the context of global climate change, this study identifies 50 flood-tolerant plants with high ecological value, and proposes guidelines for selecting flood-tolerant species. It concludes by discussing future research directions in flood tolerance and the potential applications of these plants in urban landscaping, sponge city construction, and ecological restoration.