Application of delayed luminescence measurements for the identification of herbal materials: a step toward rapid quality control

Background Herbal materials are widely used as medicinal products, dietary supplements, food, and spices. With increased consumption, the safety, quality, and efficacy of herbal materials are becoming more relevant. The authenticity of herbal materials plays an important role in herbal quality control, and there is an urgent need to develop a simple, direct, objective, rapid, and inexpensive measurement tool for the identification of herbal materials for the purpose of quality control. Methods Delayed luminescence (DL) was used to measure authentic and counterfeit herbal materials. A hyperbolic function was used to extract four properties from the DL curves of the herbal materials. Statistical tools, including Student’s t test and Principal Component Analysis, were used to differentiate authentic and counterfeit herbal materials based on the DL properties. Results Our results showed that authentic and counterfeit herbal materials could be identified based on the DL properties as follows: (a) authentic versus counterfeit materials; (b) authentic versus adulterated materials; (c) authentic versus sulfur-fumigated materials; as well as (d) authentic versus dyed materials. Conclusion The simple, direct, rapid, and inexpensive measurements offered by DL potentially offer a novel technique for the identification of Chinese herbal materials. However, the establishment of a valid database will be the next step toward the possible application of this technique, which would contribute significantly to the development of a novel digital tool for the quality control of herbal materials.

Microwave Assisted Extraction of Defatted Roselle (Hibiscus sabdariffa L.) Seed at Subcritical Conditions with Statistical Analysis

Roselle seeds are the waste product of roselle processing, but they are now labeled as a polyphenol source with great herbal quality. In this work, polyphenols were extracted using ethanol-water (70% (v/v)) in a closed vessel under microwave irradiation. The main objective was to determine the optimal parameters statistically. The influence of extraction time (4–10 min), microwave power (100–300 W), and solvent/solid ratio (25–100 mL/g) was studied. The total phenolic and flavonoids content were determined using Folin-Ciocalteu and aluminum chloride methods, respectively. Without temperature control, the subcritical conditions could occur and the highest flavonoid content (14.4251 mg QE/g) was achieved at 158°C and 16.4 bar. Although the optimum MAE conditions (10 min, 300 W, and 97.7178 mL/g) resulted in the highest yield (65.0367%) and phenolic content (18.2244 mg GAE/g), low flavonoids content (6.4524 mg QE/g) was unexpectedly obtained due to degradation at 163°C.

Study on Extraction Process and Content Determination of Safflor Yellow

The aim was to study the extraction process of safflor yellow (SY) from Cacthamus tinctorius. The SY contents of five varieties which were planted in safflower production base in Tianjin were measured and compared, in order to determine its growth adaptability and herbal quality. [Method Based on the single-factor test, the optimum extraction process can be obtained after selecting the lager factor which affected extraction rate of safflor yellow. Then the SY contents of five varieties were determined by UV-visible spectrophotometer. [Result The orthogonal test showed that the optimal extraction process was to add 10 and 12 times amount of water and extract for 30min every time at 60°C, totally for 2 times. The SY contents of five varieties were significantly higher than or equal to the standard medicinal safflor. [Conclusion Five varieties of safflower which were planted in Tianjin showed good adaptability and herbal quality. This study would provide scientific basis for improving saline-alkali soil in Tianjin.