Investigating Ghanaian Allium Species for Anti-Infective and Resistance-Reversal Natural Product Leads to Mitigate Multidrug-Resistance in Tuberculosis

Ajoene: a natural compound with enhanced antimycobacterial and antibiofilm properties mediated by efflux pump modulation and ROS generation against M. Smegmatis

Tuberculosis (TB) continues to be a primary worldwide health concern due to relatively ineffective treatments. The prolonged duration of conventional antibiotic therapy warrants innovative approaches to shorten treatment courses. In response to challenges, the study explores potential of Ajoene, a naturally occurring garlic extract-derived compound, for potential TB treatment. Mycobacterium smegmatis as a model organism for M. tuberculosis (M. tb) to investigate Ajoene's efficiency. In vitro techniques like antimicrobial susceptibility, antibiofilm, EtBr accumulation assay, and ROS assay evaluate the potency of Ajoene and conventional TB drugs against Mycobacterium smegmatis. An in-silico study also investigated the interaction between Ajoene and quorum-sensing proteins, specifically regX3, MSMEG_5244, and MSMEG_3944, which are involved in biofilm formation and sliding activity. In vitro findings revealed that Ajoene exhibited significant antibacterial activity by inhibiting growth and showing bactericidal effects. It also demonstrated additive interactions with common antibiotics such as Isoniazid and Rifampicin. Furthermore, Ajoene demonstrated a comparative interaction with commonly used antibiotics, such as Isoniazid and Rifampicin, and reduced M. smegmatis motility, both alone and in combination with these antibiotics. In silico analysis shows that Ajoene exhibited a higher binding affinity with regX3, a protein orthologous to the regX3 gene in M.tb. Ajoene also demonstrated consistent antibiofilm effects, particularly when combined synergistically with Isoniazid and Rifampicin. Mechanistic investigations demonstrated Ajoene's potential to inhibit efflux pumps and promote ROS generation in bacteria, suggesting a potential direct killing mechanism. Collectively, the findings emphasize Ajoene's effectiveness as a novel antimycobacterial and antibiofilm molecule for TB treatment.

Therapeutic Uses and Pharmacological Properties of Shallot (Allium ascalonicum): A Systematic Review

Background

Shallot (Allium ascalonicum L.) is a traditional plant species used throughout the world both for culinary purposes and as a folk remedy. To date (i.e., April 2022), there is no report on the main pharmacological activities exerted by shallot preparations and/or extracts.

Scope and Approach

The aim of this study was to comprehensively review the pharmacological activities exerted by shallot, with rigorous inclusion and exclusion criteria based on the scientific rigor of studies. Prisma guidelines were followed to perform the literature search.

Key Findings and Conclusions

The literature search yielded 2,410 articles of which 116 passed the required rigorous criteria for inclusion in this review. The extracts exert a potent antioxidant activity both in vitro and in vivo, as well as a strong inhibitory capacity on various pathogens with relevant implications for public health. Moreover, shallot can be used as adjuvant therapy in cardiovascular diseases, diabetes, cancer prevention, and other non-communicable diseases associated with inflammatory and oxidative pathways. Future studies investigating the chemical composition of this species, as well as the molecular mechanisms involved in the empirically observed pharmacological actions are required.

The Phytochemistry and Pharmacology of Tulbaghia, Allium, Crinum and Cyrtanthus: ‘Talented’ Taxa from the Amaryllidaceae

Amaryllidaceae is a significant source of bioactive phytochemicals with a strong propensity to develop new drugs. The genera Allium, Tulbaghia, Cyrtanthus and Crinum biosynthesize novel alkaloids and other phytochemicals with traditional and pharmacological uses. Amaryllidaceae biomolecules exhibit multiple pharmacological activities such as antioxidant, antimicrobial, and immunomodulatory effects. Traditionally, natural products from Amaryllidaceae are utilized to treat non-communicable and infectious human diseases. Galanthamine, a drug from this family, is clinically relevant in treating the neurocognitive disorder, Alzheimer’s disease, which underscores the importance of the Amaryllidaceae alkaloids. Although Amaryllidaceae provide a plethora of biologically active compounds, there is tardiness in their development into clinically pliable medicines. Other genera, including Cyrtanthus and Tulbaghia, have received little attention as potential sources of promising drug candidates. Given the reciprocal relationship of the increasing burden of human diseases and limited availability of medicinal therapies, more rapid drug discovery and development are desirable. To expedite clinically relevant drug development, we present here evidence on bioactive compounds from the genera Allium, Tulgbaghia, Cyrtanthus and Crinum and describe their traditional and pharmacological applications.