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Abstract: Cell suspension and Agrobacterium rhizogenes-transformed hairy root cultures of Devil’s claw (Harpagophytum procumbens), an African plant with high medicinal value, were cultivated in shake-flasks. A purification scheme to isolate their main active constituents (the phenylethanoid glycosides verbascoside, leucosceptoside A, β-OH-verbascoside and martynoside; structurally identified by NMR and LC–MS) was then developed, and their concentrations in the cultures were determined by UV spectrometry following HPLC separation. Preparations, extracts and the isolated phenylethanoid glycosides from the H. procumbens in vitro systems were tested on isolated murine macrophages to study their effects on nitric oxide (NO) and cytokine (TNF-α, IL-6) release and the expression of COX-1 and COX-2. They were also added to human serum to investigate their effects on the classical pathway of complement activation. The results indicate that the extracts and preparations of the in vitro systems, and pure verbascoside (their main active constituent), had strong anti-inflammatory properties, comparable to or even higher than that of pure harpagoside (a major anti-inflammatory constituent of intact Devil’s claw tubers). Thus, they have potential as new anti-inflammatory agents. [ABSTRACT FROM AUTHOR]

Abstract: Triterpenes are a versatile group of biologically active ingredients present in several phytoextracts. They often occur as glycoconjugates with a distinct bioactivity from their aglycone counterparts. Deglycation of triterpenes can be performed by enzymatic and chemical reactions, whereas biotransformation is generally more specific and occurs without unwanted alterations to the molecule. Further structural modification of the triterpenes to enhance their pharmaceutical relevance can be efficiently carried out by the application of biotransformational processes using microorganisms or isolated enzymes. In particular, the whole-cell process is favorable if cofactor-dependent modifications are preferred, such as hydroxylations/oxidations of the lead compound. However, the isolation of triterpenes from domestic plant material has some disadvantages such as extract variability and instability. These problems can be overcome through the use of cell culture technology, where the ex vivo cultivated cells are used for the reproducible production of the target compound. The relevant topics that should be addressed to establish a (biotransformational) production process of pharmaceutically relevant triterpenes are covered in this review. In particular, we focus on the production process using tissue engineering, the corresponding analytical techniques, and the biotransformation reaction required to obtain bioactive compounds from precursor molecules. [ABSTRACT FROM AUTHOR]