Salvia miltiorrhiza (S. miltiorrhiza) Bunge is broadly used as herbal medicine for the clinical treatments of cardiovascular and cerebrovascular diseases. Despite its commercial and medicinal values, few systematic studies on the metabolome of S. miltiorrhiza roots have been carried out so far. We systematically described the metabolic profiles of S. miltiorrhiza using high pressure liquid chromatography mass spectrometry (LC/MS) in conjunction with multivariate statistical analyses, aimed at monitoring their biological variations of secondary metabolites related to three locations and four S. miltiorrhiza genotypes. A total of 40 bioactive constituents were putatively annotated in S. miltiorrhiza root samples. This study found that both the same S. miltiorrhiza genotype growing at three different locations and four S. miltiorrhiza genotypes growing at the same location had significant metabonomic differences identified by the principal component analysis (PCA) approach. By using orthogonal projection to latent structure with discriminant analysis (OPLS-DA), 16 and 14 secondary metabolites can be used as potential location-specific and genotype-specific markers in S. miltiorrhiza, respectively. The specificity of LC/MS profiles offered a powerful tool to discriminate S. miltiorrhiza samples according to genotypes or locations.

An efficient ultrasonic-assisted extraction (UAE) method was developed for simultaneous extraction of three active compounds, forsythiaside A (FSA), phillyrin (PHI) and rutin (RT), from the fruits of Forsythia suspensa. The effects of various factors including a binary mixed solvent of methanol/water and ethanol/water, the pH of the solvent, particle size, temperature, solvent to material ratio, ultrasonic input power and extraction time on UAE were investigated in detail. The mass transfer mechanism of UAE using different mixed solvents was further explained by comparison with the maceration extraction method. The response surface methodology was used to optimize the experimental variables including ethanol concentration, solvent to material ratio and extraction time. The optimized conditions for the simultaneous extraction of RT, FSA and PHI were: particle size 60–80 mesh, temperature 30 °C, ultrasonic power 200 W, ethanol concentration 50%, solvent to material ratio 32 mL/g and extraction time 37 min. Compared to conventional extraction methods, UAE provided the highest extraction efficiency and offered many advantages including the reduction of solvent, temperature and time for extraction.

Potassium application can effectively mitigate the effects of drought stress on plant growth, and few studies have reported its application to the medicinal plant Salvia miltiorrhiza (S. miltiorrhiza). Four experimental treatments were used, including a control (Z1K0), non-drought potassium application (Z1K3), drought treatments (Z2K0), and drought-stress potassium application (Z2K3). The findings revealed that, in contrast to Z2K0, Z2K3 promoted the absorption of potassium in S. miltiorrhiza, elicited the aggregation of osmoregulatory compounds such as soluble protein and proline, and mitigated membrane impairment as a defense against the deleterious consequences of drought stress. Additionally, we extended our investigation to encompass comprehensive metabolomics analysis of the roots. Interestingly, subsequent root metabolomics analyses demonstrated that the drought application of potassium not only significantly reduced the amino acid content, but also increased the amount of terpenoids and phenolic acids in the roots. Nonetheless, the application of a particular amount of K under moderate drought conditions promoted the growth and yield of S. miltiorrhiza, but proved to be detrimental to its active ingredients. Indeed, the findings of this study offer valuable insights and recommendations for the application of potassium to mitigate the impact of drought stress in S. miltiorrhiza and other medicinal plants.

Radix Salviae miltiorrhizae, a traditional Chinese medicine, is applied widely in the treatment of cardiovascular, cerebrovascular, pulmonary, and nephritic diseases. Salvianolic acids are the main active components of Radix S. miltiorrhizae and are mainly used in the preparation of tablets, dropping pills and injections in traditional Chinese pharmaceutics. The purpose of this study is to develop an optimized spray-drying process to produce salvianolic acids particles and evaluate the physicochemical properties and in vitro deposition of the particles for application in dry powder inhalation (DPI). The spray-drying process was optimized according to a central composite design, using yield, median diameter, and the overall desirability as the responses. The physicochemical properties analysis and aerosolization properties evaluation on the particles indicated that the process obtained from multiple response optimization was more suitable for preparing particles applied in DPI. Under the optimized process, the particle size distribution analysis showed that the calculated mean aerodynamic diameter was below 3 µm. Scanning electron microscopy (SEM) studies confirmed the spherical, hollow structure and thin-walled and nearly smooth surface morphology of the particles. Aerosolization properties evaluation showed that the fine particle fraction was 36.3%. The results indicated that salvianolic acids particles produced by the optimized process could be applied in DPI. Furthermore, the present study indicated that multiple response optimization was a convenient and efficient method because it can simultaneously take into account the important factors that influence the quality of DPI.