Aspalathus linearis (Burm.f.) R. Dahlgren, commonly known as rooibos tea, was consumed traditionally by the indigenous South African inhabitants as an herbal remedy. Beside antioxidant properties, it displays antiallergic, antispasmodic, and hypoglycemic activities. An ultra-high-performance liquid chromatography method coupled with photodiode array and mass spectrometry detectors were developed for the determination of 14 phenolic constituents from leaves and stems of A. linearis. The efficient separation was performed within 30 min at a temperature of 30 °C by using C-18 column as the stationary phase and water/acetonitrile with 0.05% formic acid as the mobile phase. Method validation for linearity, repeatability, limits of detection, and limits of quantification was achieved. The limits of detection from 0.2–1 μg/mL were reported for the standard compounds. Their total content varied substantially (1.50–9.85 mg/100 mg sample) in 21 dietary supplements. The presence of regioisomers and diastereomers which co-elute on a variety of stationary phases make separation for quantification purposes challenging. This method was found to be efficient in providing low retention times and excellent resolution for this type of phytochemicals. The established method is suitable for chemical fingerprint analysis of A. linearis and cost-effective for quality control of rooibos tea products.

Overlapping geographical occurrence, history of traditional use, confusion in species identification, and morphological resemblances among various species are some considerations that necessitate the importance of qualitative analysis for efficient quality control and safer botanical products. This paper provides detailed morpho-anatomies of the leaves and stems of Tinospora cordifolia, Tinospora crispa, and Tinospora sinensis, and stems of Tinospora baenzigeri. Microscopy studies of the selected Tinospora species revealed key diagnostic features that can help distinguish the closely related species of Tinospora as well as to detect any adulteration or substitution in the raw materials. HPTLC profiles of the authenticated plant materials, as well as commercial products claiming to contain Tinospora, were compared to distinguish T. crispa from other closely related species and to establish an efficient method to assess the identity and quality of the products using qualified chemical markers. HPTLC chromatograms of both plant samples and dietary supplements were compared with six reference marker compounds. The analysis revealed that borapetoside B and C were useful to identify T. crispa while tinosineside A was found to be characteristic to authenticate the T. sinensis products.