Platycodon grandiflorus is a medical, ornamental, and edible traditional Chinese medicine whose seed germination and plant growth are frequently restricted by dormancy and stresses. In this study, we investigated how chitosan soaking affected seed germination, growth, photosynthesis, resistance, yield, and quality of P. grandiflorus. The results indicated that chitosan soaking had a preferable enhancing effect on seed germination of P. grandiflorus, which significantly (p < 0.05) promoted its germination rate, energy, and index, as well as cotyl and radicle length. Furthermore, 0.15–0.20% chitosan soaking effectively enhanced the leaf growth, height, stem diameter, and overground part dry weight of P. grandiflorus and reliably improved their leaves’ chlorophyll, photosynthetic rate, transpiration rate, and water use efficiency. Moreover, 0.15–0.20% chitosan soaking effectively enhanced the stress resistance and adaptability of P. grandiflorus via increasing its resistance substances and triggering its defense enzyme activity. Meanwhile, 0.15–0.20% chitosan soaking effectively improved the underground part growth and medical quality of P. grandiflorus. This study highlights that chitosan can be used as a favorable, efficient, and economical candidate or promoter for enhancing seed germination of P. grandiflorus and improving its growth, photosynthesis, resistance, yield, and quality; it also highlights that 0.15–0.20% chitosan is a suitable concentration.

Flower tea is widely loved as a drink, especially for the beautiful and rich flowers of the orchid family, and the drying method for different flowers is also unique. GC-MS is widely used to study volatile substances to determine the quality of flower teas. The findings show that the freeze-drying method can retain the original aroma and flavor of Bletilla striata has the highest sensory evaluation score, with the key flavor substances ethyl caproate and N-heptanal containing 1.14% and 6.28%, respectively, and their ROAV values reaching 54.46 and 100.00. Additionally, the freeze-drying method can well retain flavonoids, polysaccharides, and phenolic components, while providing better antioxidant and antibacterial properties. The stove-drying method would make Bletilla striata slightly burnt and less flavorful and efficacious than freeze-drying; the air-drying method is difficult to retain the special odor and fragrance of Bletilla striata flowers and has the lowest sensory evaluation score, with the presence of volatile components with irritating and unpleasant odors such as pyrazine and 2-pentylfuran, while not showing better efficacy. In addition, steam fixation would destroy the morphology and flavor of Bletilla striata, lose polysaccharide and phenolic components, and reduce the efficacy of Bletilla striata scented tea, but could retain the flavonoid components well. In summary, direct freeze-drying without steam fixation is the best process for drying Bletilla striata scented tea, stove-drying without steam fixation is more economical and convenient in actual production and application, steam fixation and air-drying are not suitable as drying processes for Bletilla striata scented tea. This study analyzed the quality of Bletilla striata scented tea under different drying methods, promoted the further processing of Bletilla striata scented tea, and provided a reference for the comprehensive utilization of Bletilla striata scented tea.

In this study, polysaccharides from Pleione yunnanensis (Orchidaceae, abbreviated as P. yunnanensis) were obtained by five methods: hot water extraction, microwave extraction, cold water extraction, enzymatic extraction, and ultrasonic extraction. Their structural characteristics, antioxidant properties, and hypolipidemic activities were explored. The results showed that the five polysaccharides all exhibited typical infrared spectral characteristics of polysaccharides. Their monosaccharide compositions were basically the same, all consisting of glucose and mannose, but their surface morphologies differed significantly. The polysaccharide extracted by the enzymatic method had the lowest molecular weight but showed good antioxidant properties. The polysaccharides extracted by ultrasonic and cold water methods showed great potential for hypolipidemic effects. Different extraction methods had impacts on the physicochemical properties, biological activities, and microstructures of P. yunnanensis polysaccharides. In practical applications, it is necessary to select appropriate extraction methods according to different requirements. The results of this study provide a reference basis for the precise development and utilization of P. yunnanensis polysaccharides.

Bletilla striata is a valuable Chinese herbal medicinal plant widely used in various fields. To meet the market demand for this herb, the tissue culture technology of B. striata was developed. However, drought stress has been a significant threat to the survival of cultivated B. striata. To further understand the underlying mechanisms of B. striata under drought stress, its response was investigated at the physiological and transcriptional levels. Our photosynthesis results show that the decline of the net photosynthesis rate (Pn) in B. striata leaves was mainly caused by nonstomatal limitation factors. Using transcriptomic analysis 2398, differentially expressed genes (DEGs) were identified. KEGG enrichment analysis showed that DEGs involved in plant hormone signal transduction (ko04075) were significantly altered, especially the abscisic-acid signaling pathway. The up-regulations of the serine/threonine protein kinase (SnRK2) and S-type anion (SLAH2) channels might lead to stomatal closure, which is the reason for decline of photosynthesis. Moreover, the downregulation of cytochrome b6 and photosystem I reaction center subunit III/IV might be the major reason for nonstomatal limitation. In addition, B. striata enhanced the ability of ROS scavenging via activating the gene expression of superoxide dismutase, catalase, and peroxidase in response to drought stress. Our study enhanced the understanding of B. striata in response to drought stress.

Bletilla striata polysaccharide (BSP) and chitosan (CS) were chemically cross-linked using oxalyl chloride to prepare a composite hemostatic sponge (BSP-CS), and the process parameters were optimized using the Box–Behnken design (BBD) with response surface methodology. To optimize the performance of the hemostatic sponge, we adjusted the ratio of independent variables, the amount of oxalyl chloride added, and the freeze-dried volume. A series of evaluations were conducted on the hemostatic applicability of BSP-CS. The characterization results revealed that BSP-CS had a stable bacteriostatic effect on Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa within 72 h, and the bacteriostatic rate was above 30%. The CCK-8 cytotoxicity test demonstrated that BSP–CS had a certain effect on promoting cell proliferation of L929 cells. In the mouse tail-cutting experiment, the hemostasis time of BSP–CS was 463.0±38.16 s, shortened by 91.3 s on average compared with 554.3±34.67 s of the gauze group. The blood loss of the BSP–CS group was 28.47±3.74 mg, which was 34.7% lower than that of the control gauze group (43.6±3.83 mg). In the in vitro coagulation experiment, the in vitro coagulation index of the BSP–CS group was 97.29%±1.8%, which was reduced to 8.6% of the control group. The CT value of the BSP–CS group was 240±15 s, which was 155 s lower than that of the gauze group (355±31.22 s). All characterization results indicate that BSP–CS is an excellent hemostatic material.

Exogenous application of plant hormones has been considered a short-term and effective strategy to alleviate deleterious effects of water stress on plants. However, whether exogenous gibberellic acid (GA₃) directly enhances nitrogen accumulation and thereby alleviates drought stress in soybean (Glycine max (Linn.) Merr.) remains to be investigated. This study set three water treatments (75% CK, 50% MD, 25% SD), with half of the plants at each level sprayed with 10⁻⁶ mol·L⁻¹ GA₃, measuring growth, photosynthesis, nitrogen content, water status, and electrophysiological parameters and calculating cellular metabolic electronic energy (ΔG_B) based on Nernst equation. The results showed that drought reduced soybean nitrogen accumulation, photosynthesis, growth and yield. GA₃ increased soybean nitrogen accumulation, improving photosynthesis and yield under CK, which enhanced the consumption of intracellular stored energy and reduced ΔG_B. Under MD, GA₃ improved leaf water status, promoted soybean nitrogen accumulation and photosynthesis and reduced ΔG_B by allocating more energy to drought resistance; it could therefore mitigate the moderate drought stress on plants. ΔG_B negatively correlated with total nitrogen content and yield, indicating that ΔG_B was a potential indicator associated with nitrogen accumulation, which can guide the optimization of GA₃ spraying strategies. Further studies on GA₃ application details are necessary to improve the soybean yields under drought conditions.