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Green Metal-Based Nanoparticles Synthesized Using Medicinal Plants and Plant Phytochemicals against Multidrug-Resistant Staphylococcus aureus
Published in Richard L. K. Glover, Daniel Nyanganyura, Rofhiwa Bridget Mulaudzi, Maluta Steven Mufamadi, Green Synthesis in Nanomedicine and Human Health, 2021
Abeer Ahmed Qaed Ahmed, Lin Xiao, Tracey Jill Morton McKay, Guang Yang
In the search for alternative solutions against MRSA, the stem bark and leaf of Tabernaemontana alternifolia (Roxb) (an indigenous Indian medicine used to treat skin infections) were tested to determine their antibacterial activity against MRSA. T. alternifolia stem bark aqueous extracts showed antibacterial effects against MRSA and VRSA. The MIC values ranged from 600 to 800 μg/ml for MRSA. The phytochemical profiling showed that saponins, alkaloids, coumarins, flavonoids and steroids were present. Moreover, T. alternifolia extract did not show any cytotoxic activity towards Vero cells, making the extract a good candidate to treat MRSA infections (Marathe et al., 2013). This is also true for Tabernaemontana stapfiana (Britten) where different solvents of root and stem extracts showed good antibacterial activity. The phytochemical profiling showed that tannins, alkaloids, coumarins, flavonoids and saponins were present, all of which are associated with antimicrobial effects. The methanolic extract exhibited good antibacterial effects against the tested bacterial strains, including MRSA with MIC ranging between 15.6 and 500 mg/ml. MBC ranged between 31.25 and 500 mg/ml (Ruttoh et al., 2009).
Plant Alkaloids and Their Derivatives Relevant to Alzheimer’s Disease
Published in Atanu Bhattacharjee, Akula Ramakrishna, Magisetty Obulesu, Phytomedicine and Alzheimer’s Disease, 2020
Atanu Bhattacharjee, Akula Ramakrishna
Thin-layer chromatography (TLC) analysis of AChE inhibitory activity (using Ellman’s method) of voacangine and voacangine hydroxyindolenine [Figure 17.2(iii & iv)] isolated from Tabernaemontana australis (Family: Apocynaceae) showed a detectable spot at the minimum concentration of 25 μM (Andrade et al., 2005).
Total Synthesis of Some Important Natural Products from Brazilian Flora
Published in Luzia Valentina Modolo, Mary Ann Foglio, Brazilian Medicinal Plants, 2019
Leonardo da Silva Neto, Breno Germano de Freitas Oliveira, Wellington Alves de Barros, Rosemeire Brondi Alves, Adão Aparecido Sabino, Ângelo de Fátima
Another indole alkaloid found in South American plants was (+)-affinisine 29, which exhibits relevant pharmacological activities and has been isolated from ethanolic extracts of ground whole plant of Peschiera affinis (Apocynaceae; grão-de-galo) collected in northeastern Brazil (Santos, Magalhães, et al., 2009; Weisbach et al., 1963). This compound is also found in Tabernaemontana hystrix (Apocynaceae; esperta), a species of plant native to Southeastern Brazil, known as “esperta” (Monnerat et al., 2005). Although the alkaloid affinisine 29 possesses important biological activities, there are no syntheses described to date. However, Liu and coworkers have shown an elegant synthetic approach to obtain the (−)-enantiomer of affinisine in a total of nine steps and a 22% overall yield (Figure 12.9) (Liu et al., 2000). Starting from l-tryptophan derivative 30, asymmetric Pictet-Spengler cyclization was employed to afford adduct 31 with 100% diastereoselectivity. This process is the key transformation and one of more used approaches to access other indole alkaloids (Li et al., 1999; Wang et al., 1998). As stated before, although there is no synthesis to natural alkaloid 29, an enantiomer from an intermediate posterior to compound 31 was already obtained in previous works (Li et al., 1999; Wang et al., 1998; Yu and Cook, 1998), suggesting the possibility of accessing the natural (+)-affinisine (29).
Advances in lyotropic liquid crystal systems for skin drug delivery
Published in Expert Opinion on Drug Delivery, 2020
Ana Vitoria Pupo Silvestrini, Angelo Luis Caron, Juliana Viegas, Fabíola Garcia Praça, Maria Vitoria Lopes Badra Bentley
In investigations by Zhang et al. (2015) [211], a cubic phase gel composed of GMO, diethylene glycol monoethyl ether, and water was formulated for the incorporation and transdermal delivery of de baicalin, a natural active with potent anti-inflammatory, antiallergic, antibacterial and antioxidant effects. The application of LLC systems resulted in a higher transdermal flow than baicalin incorporated in a carbopol-based hydrogel. It was suggested that the cubic phase, due to its biological structure similar to the cutaneous membrane, promoted a strong bioadhesive property for the skin, thus allowing the fusion of GMO with the SC lipophilic layer, where baicalin was then released from the curved bicontinuous lipid bilayer [211]. In another study, the application of a lamellar phase gel containing an extract from Tabernaemontana divaricata increased the transdermal delivery of the extract, which was related to the presence of interlamellar water in the LLC phase, which acts as a reservoir for controlled skin hydration [212].
Brazilian medicinal plants with corroborated anti-inflammatory activities: a review
Published in Pharmaceutical Biology, 2018
Victor Pena Ribeiro, Caroline Arruda, Mohamed Abd El-Salam, Jairo Kenupp Bastos
Jatropha elliptica (Pohl) Oken (Euphorbiaceae) (Ferreira-Rodrigues et al. 2016), Justicia pectoralis Jacq. (Acanthaceae) (Leal et al. 2000), Kalanchoe brasiliensis Cambess (Crassulaceae) (Costa et al. 2006), Magnolia ovata (A. St.-Hil) Spreng. (Magnoliaceae) (Kassuya et al. 2009); Mikania glomerata Spreng. (Asteraceae) (Fierro et al. 1999); Myracroduon urundeuva Allemao (Anacardiaceae) (Souza et al. 2007), Peschiera australis (Mull. Arg.) Miers (Apocynaceae) – Tabernaemontana catharinensis D.C. (Apocynaceae) (Rates et al. 1993), Piper marginatum Jacq. (Piperaceae) (D’Angelo et al. 1997), Plinia edulis (Vell.) Sobral (Myrtaceae) (Azevedo et al. 2016), Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae) (Penido, Costa, Futuro, et al. 2006), Tabebuia impetiginosa (Mart. Ex. D.C.) Standl. (Bignoniaceae) (Koyama et al. 2000), Vanillosmopsis arborea (Gardner) Kaber. (Asteraceae) (Santos et al. 2015), Virola michelii Heckel (Myristicaceae) Carvalho, Sertie, et al. (1999), Ximenia americana L. (Ximeniaceae) (Shettar et al. 2015), Zeyheria montana Mart. (Bignoniaceae) (Guenka et al. 2008), Byrsonima intermedia A. Juss (Malpighiaceae) (Orlandia et al. 2011), and other plants native to Brazil with anti-inflammatory activities need further studies to fully elucidate their mechanisms of action.
Green synthesis of copper nanoparticles using Cissus vitiginea and its antioxidant and antibacterial activity against urinary tract infection pathogens
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2020
Shuang Wu, Shanmugam Rajeshkumar, Malini Madasamy, Vanaja Mahendran
Now a day non-conventional antioxidant and antibacterial agents are becoming key in the pharmaceutical research field. The results of antibacterial action of spherical shaped nano copper treated against UTI pathogens, namely E.coli, Enterococcus sp., Proteus sp. and Klebsiella sp. and the zone of inhibition around the copper nanparticles loaded disc was noted and measured (Figure 7). From our results, we observed that copper nanoparticles highly active against E. coli and Enterococcus sp. it shows the high zone of inhibition around 22.2 and 20.3 mm in diameter, respectively. Klebsiella sp. exhibit moderately inhibition (18.5 mm) whereas Proteus sp. exhibit less sensitivity (16.33 mm) to copper nanoparticles. Likewise, Ruparehia et al. [30] reported that E. coli showed higher sensitivity to nano copper. It was the strains of E. coli and Enterococcus sp. was the more resistant microorganisms being higher than 80 and 70%, respectively. This nano copper appears to push its killing effect by introducing reactive hydroxyl radicals that can cause irrespirable damage such as the oxidation of proteins, separation of RNA and DNA molecules and cell membrane mutilation due to lipid peroxidation. Similarly, Sivaraj et al. [31] proved that Tabernaemontana divaricate leaves mediated synthesized copper oxide nanoparticles were very effective nanomaterials against UTI pathogen especially E. coli. The nano copper proved that forcible inhibits the growth of UTI pathogens namely E. coli, Enterococcus sp., Proteus sp. and Klebsiella sp.