Phytochemistry of the genus Skimmia (Rutaceae)

Skimmia anquetilia N.P. Taylor and Airy Shaw (Rutaceae): A Critical Appriasal of its Ethnobotanical and Pharmacological Activities

Skimmia anquetilia N.P. Taylor and Airy Shaw (Rutaceae) is a perennial, aromatic, gregarious wild ornamental shrub native to the Western Himalaya. The plant is used in the traditional medicinal system to treat copious health conditions like rheumatism, fever, inflammation, headache, influenza, body-ache, clearing of the nose, diabetes, lowering the body temperature, smallpox, wounds, burns, snake, and scorpion bites. Phytochemical and gas chromatography-mass spectrometer (GC-MS) analysis of S. anquetilia showed the presence of alkanes, alkenes, carboxylic acids, fatty acids, and their esters, simple coumarins, terpenes, phenylpropanoid, and so on. These active principles exhibit a wide array of pharmacological effects, including anti-inflammatory, antioxidant, anti-cancerous, anti-feedant, and antibacterial properties. Most pharmacological studies were based on the essential oil and the crude extracts of the plant and the bioactive compounds responsible for the bioefficacy have not been well-identified. Further investigations are required to transform the experience-based claims on the use of S. anquetilia in traditional medicine practices into evidence-based information. Detailed in-vitro and in-vivo studies on the mechanisms of action of pure bioactive compounds and more elaborate toxicity studies to ensure plant safety for human use should be conducted. This review recapitulates the current status of its use in the ethnobotany, phytochemistry, and pharmacological activities. It also offers a critical assessment of the plant's existing information which would help to recuperate its potential as a source for drug development of lead molecules.

Two new methoxylated flavones isolated from Casimiroa edulis La Llave and their MMP-9 inhibitory activity

Casimiroa edulis La Llave is known to contain unusual 5,6-dimethoxyflavones bearing a variously oxygenated B-ring. Phytochemical investigation of the leaves and the roots of C. edulis achieved the isolation of two new methoxylated flavones, named casedulones A (1) and B (2), together with 12 known analogues. Their unique structures were established with the aid of spectral analyses and total syntheses. Pre-treatment with 20 µM of 1 and 2 suppressed MMP-9 expression in LPS-mediated THP-1 cells, indicating that the characteristic flavonoids in C. edulis could be potential anti-angiogenics for cancer prevention.

New coumarin from the roots of Prangos pabularia

The new coumarin 1, yuganin A (7-methoxy-8-((1S,2S)-1,2,3-trihydroxy-3-methylbutyl)-2H-chromen-2-one) along with nine known coumarins, heraclenol 3'-O-β-D-glucopyranoside (2), oxypeucedanin hydrate 3'-O-β-D-glucopyranoside (3), heraclenol (4), oxypeucedanin hydrate (5), osthole (6), oxypeucedanin (7), heraclenin (8), isoimperatorin (9), imperatorin (10) and the disaccharide sucrose (11), have been isolated from the roots of Prangos pabularia, and the structures of these isolated compounds were elucidated by spectroscopic means, especially, UV, HR-ESIMS, and 1D and 2D NMR spectroscopy. Furthermore, the anti-melanogenic effect of yuganin A and its inhibitory effect on B16 cells were evaluated. Yuganin A may be useful in the treatment of hyperpigmentation and as a skin-whitening agent in the cosmetics industry.

Comparative study on alkaloids and their anti-proliferative activities from three Zanthoxylum species

Background

Alkaloids have been considered as the most promising bioactive ingredients in plant species from the genus Zanthoxylum. This study reports on the compositions and contents of the Zanthoxylum alkaloids (ZAs) from three Zanthoxylum species, and their potential anti-proliferation activities.

Methods

An HPLC-UV/ESI-MS/MS method was established and employed to analyze the alkaloids in different Zanthoxylum extracts. The common and unique peaks and their relative contents were summarized and compared to evaluate the similarity and dissimilarity of the three Zanthoxylum species. Meanwhile, inhibitory activity tests to four carcinoma cell lines, i.e., stomach tumor cells (SGC-7901), cervical tumor cells (Hela), colon tumor cells (HT-29) and Hepatic tumor cells (Hep G2), were carried out in vitro to evaluate the bioactivities of the ZAs.

Results

Seventy peaks were detected in the crude total alkaloid samples, and 58 of them were identified. As a result, 13 common peaks were found in the extracts of all the three Zanthoxylum species, while some unique peaks were also observed in specific species, with 17 peaks in Z. simulans, 15 peaks in Z. ailanthoides and 11 peaks in Z. chalybeum, respectively. The comparison of the composition and relative contents indicated that alkaloids of benzophenanthridine type commonly present in all the three Zanthoxylum species with high relative contents among the others, which are 60.52% in Z. ailanthoides, 30.52% in Z. simulans and 13.84% in Z. chalybeum, respectively. In terms of activity test, Most of the crude alkaloids extracts showed remarkable inhibitory activities against various tumor cells, and the inhibitory rates ranged from 60.71 to 93.63% at a concentration of 200 μg/mL. However, SGC-7901 cells seemed to be more sensitive to the ZAs than the other three cancer cells.

Conclusion

The alkaloid profiles detected in this work revealed significant differences in both structures and contents among Zanthoxylum species. The inhibitory rates for different cancer cells in this study indicated that the potential anti-cancer activity should be attributed to quaternary alkaloids in these three species, which will provide great guidance for further exploring this traditional medicinal resource as new healthcare products.

Synthesis and anti-inflammatory evaluation of N-sulfonyl anthranilic acids via Ir(III)-catalyzed C-H amidation of benzoic acids

The iridium(III)-catalyzed ortho-C-H amidation of benzoic acids with sulfonyl azides is described. These transformations allow the facile generation of N-sulfonyl anthranilic acids, which are known as crucial scaffolds found in biologically active molecules. In addition, all synthetic products were evaluated for in vitro anti-inflammatory activity against interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) with lipopolysaccharide (LPS)-induced RAW264.7 cells. Notably, compounds 4c and 4d, generated from p-OMe- and p-Br-sulfonyl azides, were found to display potent anti-inflammatory property stronger than that of well-known NSAIDs ibuprofen.

Medicinal plants used in the traditional management of diabetes and its sequelae in Central America: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Globally 387 million people currently have diabetes and it is projected that this condition will be the 7th leading cause of death worldwide by 2030. As of 2012, its total prevalence in Central America (8.5%) was greater than the prevalence in most Latin American countries and the population of this region widely use herbal medicine. The aim of this study is to review the medicinal plants used to treat diabetes and its sequelae in seven Central American countries: Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama.

MATERIALS AND METHODS

We conducted a literature review and extracted from primary sources the plant use reports in traditional remedies that matched one of the following disease categories: diabetes mellitus, kidney disease, urinary problems, skin diseases and infections, cardiovascular disease, sexual dysfunctions, visual loss, and nerve damage. Use reports were entered in a database and data were analysed in terms of the highest number of use reports for diabetes management and for the different sequelae. We also examined the scientific evidence that might support the local uses of the most reported species.

RESULTS

Out of 535 identified species used to manage diabetes and its sequelae, 104 species are used to manage diabetes and we found in vitro and in vivo preclinical experimental evidence of hypoglycaemic effect for 16 of the 20 species reported by at least two sources. However, only seven of these species are reported in more than 3 studies: Momordica charantia L., Neurolaena lobata (L.) R. Br. ex Cass., Tecoma stans (L.) Juss. ex Kunth, Persea americana Mill., Psidium guajava L., Anacardium occidentale L. and Hamelia patens Jacq. Several of the species that are used to manage diabetes in Central America are also used to treat conditions that may arise as its consequence such as kidney disease, urinary problems and skin conditions.

CONCLUSION

This review provides an overview of the medicinal plants used to manage diabetes and its sequelae in Central America and of the current scientific knowledge that might explain their traditional use. In Central America a large number of medicinal plants are used to treat this condition and its sequelae, although relatively few species are widely used across the region. For the species used to manage diabetes, there is variation in the availability and quality of pharmacological, chemical and clinical studies to explain traditional use.