Sustainable Production of Ajuga Bioactive Metabolites Using Cell Culture Technologies: A Review.

The genus Ajuga (Lamiaceae) is rich in medicinally important species with biological activities ranging from anti-inflammatory, antitumor, neuroprotective, and antidiabetic to antibacterial, antiviral, cytotoxic, and insecticidal effects. Every species contains a unique and complex mixture of bioactive metabolites-phytoecdysteroids (PEs), iridoid glycosides, withanolides, neo-clerodane terpenoids, flavonoids, phenolics, and other chemicals with high therapeutic potential. Phytoecdysteroids, the main compounds of interest, are natural anabolic and adaptogenic agents that are widely used as components of dietary supplements. Wild plants remain the main source of Ajuga bioactive metabolites, particularly PEs, which leads to frequent overexploitation of their natural resources. Cell culture biotechnologies offer a sustainable approach to the production of vegetative biomass and individual phytochemicals specific for Ajuga genus. Cell cultures developed from eight Ajuga taxa were capable of producing PEs, a variety of phenolics and flavonoids, anthocyanins, volatile compounds, phenyletanoid glycosides, iridoids, and fatty acids, and demonstrated antioxidant, antimicrobial, and anti-inflammatory activities. The most abundant PEs in the cell cultures was 20-hydroxyecdysone, followed by turkesterone and cyasterone. The PE content in the cell cultures was comparable or higher than in wild or greenhouse plants, in vitro-grown shoots, and root cultures. Elicitation with methyl jasmonate (50-125 µM) or mevalonate and induced mutagenesis were the most effective strategies that stimulated cell culture biosynthetic capacity. This review summarizes the current progress in cell culture application for the production of pharmacologically important Ajuga metabolites, discusses various approaches to improve the compound yield, and highlights the potential directions for future interventions.

Compositional Analysis and Potent Insecticidal Activity of Supercritical CO2 Fluid Extracts of Alcea nudiflora L. Leaves.

To mitigate potentially severe food shortages due to the exponential growth of the global population, it is of paramount importance to improve the yield and quality of globally harvested food crops. As pest control contributes to both these aspects, the development of safe and effective pesticides is one of the main strategies pursued in this direction in the context of agricultural chemistry. During our investigation of natural pesticides, a supercritical CO2 fluid extract of Alcea nudiflora L. was found to exert extremely potent insecticidal activity against aphids (Macrosiphum euphorbiae) and cowpea seed beetles (Callosobruchus maculatus) with LC50 values of 0.03 mg/mL (24 h exposure, contact method). The facts that their insecticidal activity is in the most potent class among the essential oils known to date, and that the extract did not show any toxicity toward beneficial insects such as ladybugs (Coccinella magnifica) and European honeybees (Apis mellifera Linnaeus), indicate that this extract could be a good, natural, and safe new pesticide candidate. A compositional analysis of this extract was carried out using GC/MS.