Phytochemical Constituents of Tulbaghia violacea Harv Extract and its Antifungal Potential Against Cryptococcus neoformans and Cryptococcus gattii

Author(s): Mitradev Pattoo, Vuyokazi Belewa, Benesh Munilal Somai*

Journal Name: The Natural Products Journal

Volume 9 , Issue 4 , 2019

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Graphical Abstract:


Background: In both the developed and developing world, the mortality rates of people afflicted with cryptococcosis are unacceptably high despite the availability of antifungal therapy. The disease is caused by Cryptococcus neoformans (predominantly in immunocompromised individuals) and by Cryptococcus gattii. Globally the disease is estimated to cause around 600,000 deaths annually. Antifungal therapy is available, but in the developing world, may be unaffordable to many people, there is an increasing threat of resistance to the available drugs and our repertoire of antifungal drugs is very limited. Consequently, more research has been focusing on the use of medicinal plants as therapeutic agents. The originality of the current study is that although Tulbaghia violacea is a well-documented medicinal plant, the chemical composition of aqueous extracts and their antifungal potential against pathogenic yeasts are unknown. This is the first study that evaluates the chemical constituents of aqueous T. violacea root, leaf, rhizome and tuber extracts and their corresponding antifungal activities against C. neoformans and C. gattii.

Objectives: The study aimed to investigate the phytochemical composition and antifungal potential of Tulbaghia violacea root, leaf, rhizome and tuber extracts against Cryptococcus neoformans and Cryptococcus gattii.

Methods: Roots, leaves, rhizomes and tubers were extracted with water only for 48 h at room temperature with continuous shaking. Extracts were filter sterilized, freeze-dried and, chemically analyzed for saponin, flavonol, phenolic and tannin content. Chemical constituents of each extract were also identified by GC-MS analysis. The Minimum Inhibitory Concentration (MIC) of suitably diluted extracts of each plant part were also performed against C. neoformans and C. gattii, yeast pathogens commonly associated with HIV/AIDS sufferers.

Results: Phytochemical analysis showed different concentrations of saponins (between 1023 and 2896.73 µg/ml), phenolics (between 16.48 and 51.58 µg/ml) and tannins (between 122.30 and 543.07 µg/ml) present in the different extracts. No flavonols were detected. GC-MS analysis identified a complex mixture of phytochemicals composed predominantly of sulphide, pyran, furan and ketone containing compounds to be present in the different plant parts. All extracts were dominated by the presence of 4 H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl, a pyran known to have antifungal properties. Although the root, leaf, rhizome and tuber extracts exhibited antifungal activities against both fungi, the rhizome and tuber extract were found to possess the lowest MIC’s of 1.25 mg/ml and 2.5 mg/ml against Cryptococcus neoformans and Cryptococcus gattii respectively.

Conclusion: T. violacea extracts have a complex constituent of phytochemicals and each plant part exhibited a strong antifungal activity against C. neoformans and C. gattii. The rhizome and tuber extracts showed the highest antifungal activity against C. neoformans and C. gattii respectively. Thus, T. violacea aqueous extracts are strong candidates for further development into an antifungal chemotherapeutic agent.

Keywords: Cryptococcus neoformans, Cryptococcus gattii, phytochemical analysis, antifungal, 4 H pyran-4-one DDMP, chemotherapeutic agent.

Perfect, J.R. Fungal diagnosis: How do we do it and can we do better? Curr. Med. Res. Opin., 2013, 29(Suppl. 4), 3-11.
[] [PMID: 23621588]
Panackal, A.A.; Wuest, S.C.; Lin, Y.C.; Wu, T.; Zhang, N.; Kosa, P.; Komori, M.; Blake, A.; Browne, S.K.; Rosen, L.B.; Hagen, F.; Meis, J.; Levitz, S.M.; Quezado, M.; Hammoud, D.; Bennett, J.E.; Bielekova, B.; Williamson, P.R. Paradoxical immune responses in non-HIV cryptococcal meningitis. PLoS Pathog., 2015, 11(5)e1004884
[] [PMID: 26020932]
Perfect, J.R.; Cox, G.M. Drug resistance in Cryptococcus neoformans. Drug Resist. Updat., 1999, 2(4), 259-269.
[] [PMID: 11504497]
Loyse, A.; Thangaraj, H.; Easterbrook, P.; Ford, N.; Roy, M.; Chiller, T.; Govender, N.; Harrison, T.S.; Bicanic, T. Cryptococcal meningitis: Improving access to essential antifungal medicines in resource-poor countries. Lancet Infect. Dis., 2013, 13(7), 629-637.
[] [PMID: 23735626]
Fennell, C.W.; Lindsey, K.L.; McGaw, L.J.; Sparg, S.G.; Stafford, G.I.; Elgorashi, E.E.; Grace, O.M.; Van Staden, J. Assessing African medicinal plants for efficacy and safety: Pharmacological screening and toxicology. J. Ethnopharmacol., 2004, 94(2-3), 205-217.
[] [PMID: 15325724]
Elgorashi, E.E.; Taylor, J.L.; Maes, A.; Van Staden, J.; De Kimpe, N.; Verschaeve, L. Screening of medicinal plants used in South African traditional medicine for genotoxic effects. Toxicol. Lett., 2003, 143(2), 195-207.
[] [PMID: 12749823]
Kubec, R.; Velísek, J.; Musah, R.A. The amino acid precursors and odor formation in society garlic (Tulbaghia violacea Harv.). Phytochemistry, 2002, 60(1), 21-25.
[] [PMID: 11985847]
Ncube, B.; Ngunge, V.N.; Finnie, J.F.; Van Staden, J. A comparative study of the antimicrobial and phytochemical properties between outdoor grown and micropropagated Tulbaghia violacea Harv. plants. J. Ethnopharmacol., 2011, 134(3), 775-780.
[] [PMID: 21291985]
Belewa, V.; Baijnath, H.; Somai, B.M. Aqueous extracts from the bulbs of Tulbaghia violacea are antifungal against Aspergillus flavus. J. Food Saf., 2011, 31, 176-184.
Nteso, L.; Pretorius, J.C. Tulbaghia violacea L.: In vitro antimicrobial properties towards plant pathogens. Aust. J. Agric. Res., 2006, 57, 511-516.
Sun, B.; Ricardo-da-Silva, J.; Spranger, I. Critical factors of vanillin assay for catechins and proanthocyanidins. J. Agric. Food Chem., 1998, 46, 4267-4274.
Eid, H.H.; Metwally, G.F. Phytochemical and biological study of callus cultures of Tulbaghia violacea Harv. Cultivated in Egypt. Nat. Prod. Res., 2017, 31(15), 1717-1724.
[] [PMID: 28278648]
Jahn, B.; Martin, E.; Stueben, A.; Bhakdi, S. Susceptibility testing of Candida albicans and Aspergillus species by a simple microtiter menadione-augmented 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. J. Clin. Microbiol., 1995, 33(3), 661-667.
[PMID: 7751374]
Fothergill, A.W. Interactions of yeasts, moulds, and antifungal agents: How to detect resistance Hall, G., Ed.; Humana Press: Texas, 2012, XIV, pp. 65-74.
Makkar, H.; Siddhuraju, P.; Becker, K. Plant Secondary Metabolites; Himana Press: Totowa, New Jersey, 2007.
Hue, S.M.; Boyce, A.N.; Somasundram, C. Antioxidant activity, phenolic and flavonoid contents in the leaves of different varieties of sweet potato (Ipomoea batatas). Aust. J. Crop Sci., 2012, 6, 375-380.
Newman, D.J.; Cragg, G.M. Natural products as sources of new drugs from 1981 to 2014. J. Nat. Prod., 2016, 79(3), 629-661.
[] [PMID: 26852623]
Neilson, E.H.; Goodger, J.Q.; Woodrow, I.E.; Møller, B.L. Plant chemical defense: at what cost? Trends Plant Sci., 2013, 18(5), 250-258.
[] [PMID: 23415056]
Belewa, V.; Baijnath, H.; Frost, C.; Somai, B.M. Tulbaghia violacea Harv. plant extract affects cell wall synthesis in Aspergillus flavus. J. Appl. Microbiol., 2017, 122(4), 921-931.
[] [PMID: 28132403]
De Lucca, A.J.; Bland, J.M.; Vigo, C.B.; Cushion, M.; Selitrennikoff, C.P.; Peter, J.; Walsh, T.J. CAY-I, a fungicidal saponin from Capsicum sp. fruit. Med. Mycol., 2002, 40(2), 131-137.
[] [PMID: 12058725]
Yang, C.R.; Zhang, Y.; Jacob, M.R.; Khan, S.I.; Zhang, Y.J.; Li, X.C. Antifungal activity of C-27 steroidal saponins. Antimicrob. Agents Chemother., 2006, 50(5), 1710-1714.
[] [PMID: 16641439]
Augustin, J.M.; Kuzina, V.; Andersen, S.B.; Bak, S. Molecular activities, biosynthesis and evolution of triterpenoid saponins. Phytochemistry, 2011, 72(6), 435-457.
[] [PMID: 21333312]
Coleman, J.J.; Okoli, I.; Tegos, G.P.; Holson, E.B.; Wagner, F.F.; Hamblin, M.R.; Mylonakis, E. Characterization of plant-derived saponin natural products against Candida albicans. ACS Chem. Biol., 2010, 5(3), 321-332.
[] [PMID: 20099897]
Sandrock, R.W.; Vanetten, H.D. Fungal sensitivity to and enzymatic degradation of the phytoanticipin α-tomatine. Phytopathology, 1998, 88(2), 137-143.
[] [PMID: 18944982]
Kennedy, D.O.; Wightman, E.L. Herbal extracts and phytochemicals: plant secondary metabolites and the enhancement of human brain function. Adv. Nutr., 2011, 2(1), 32-50.
[] [PMID: 22211188]
Fukai, T.; Yonekawa, M.; Hou, A.J.; Nomura, T.; Sun, H.D.; Uno, J. Antifungal agents from the roots of Cudrania cochinchinensis against Candida, Cryptococcus, and Aspergillus species. J. Nat. Prod., 2003, 66(8), 1118-1120.
[] [PMID: 12932139]
Martins, C.V.; Da Silva, D.L.; Neres, A.T.; Magalhães, T.F.; Watanabe, G.A.; Modolo, L.V.; Sabino, A.A.; De Fátima, A.; De Resende, M.A. Curcumin as a promising antifungal of clinical interest. J. Antimicrob. Chemother., 2009, 63(2), 337-339.
[] [PMID: 19038979]
Paiva, P.; Gomes, F.; Napoleão, T.; Sá, R.; Correia, M.; Coelho, L. Current Research, Technology and Education Topics in Applied Microbiology and Microbial Biotechnology Mendez-Vilas, A., Ed., Badajoz, Spain 2010
Hagerman, A. The Tannin Handbook; Miami University: Oxford, Ohio, 2002.
De Oliveira, L.F.S.; Fuentefria, A.M. Klein, Fda, S.; Machado, M.M. Antifungal activity against Cryptococcus neoformans strains and genotoxicity assessment in human leukocyte cells of Euphorbia tirucalli L. Braz. J. Microbiol., 2015, 45(4), 1349-1355.
[] [PMID: 25763040]
Ishida, K.; Rozental, S.; De Mello, J.C.; Nakamura, C.V. Activity of tannins from Stryphnodendron adstringens on Cryptococcus neoformans: Effects on growth, capsule size and pigmentation. Ann. Clin. Microbiol. Antimicrob., 2009, 8, 29.
[] [PMID: 19891776]
Chung, K.T.; Wei, C.I.; Johnson, M. Are tannins a double-edged sword in biology and health? Trends Food Sci. Technol., 1998, 9, 168-175.
Pino, J.A.; Quijano-Celís, C.E.; Fuentes, V. Volatile compounds of Tulbaghia violacea Harv. J. Essent. Oil. Bear. Pl., 2008, 11, 203-207.
Soyingbe, O.; Oyedeji, A.; Basson, A.; Singh, M.; Opoku, A. Chemical composition, antimicrobial and antioxidant properties of the essential oils of Tulbaghia violacea Harv LF. Afr. J. Microbiol. Res., 2013, 7, 1787-1793.
Kim, Y.S.; Kim, K.S.; Han, I.; Kim, M.H.; Jung, M.H.; Park, H.K. Quantitative and qualitative analysis of the antifungal activity of allicin alone and in combination with antifungal drugs. PLoS One, 2012, 7(6) e38242
[] [PMID: 22679493]
Teoh, Y.; Don, M.; Ujang, S. Media selection for mycelia growth, antifungal activity against wood-degrading fungi, and GC-MS study by Pycnoporus sanguineus. BioResources, 2011, 6, 2719-2731.
Gopalakrishnan, K.; Udayakumar, R. GC-MS analysis of phytocompounds of leaf and stem of Marsilea quadrifolia (L.). Int. J. Biochem. Res. Rev., 2014, 4, 517-526.
Uchegbu, R.I.; Akalazu, J.N.; Ukpai, K.U.; Iwu, I.C. Antimicrobial assessment of Annona muricata fruits and its chemical compositions. Asian J. Med. Health, 2017, 3, 1-7.
Meirelles, G.; Pippi, B.; Hatwig, C.; De Barros, F.; De Oliveira, L.; Von Poser, G.; Fuentefria, A. Synergistic antifungal activity of the lipophilic fraction of Hypericum carinatum and fluconazole. Rev. Bras. Farmacogn., 2017, 27, 118-123.
Sorrell, T.C. Cryptococcus neoformans variety gattii. Med. Mycol., 2001, 39(2), 155-168.
[] [PMID: 11346263]
Kwon-Chung, K.; Fraser, J.; Doering, T.; Wang, Z.; Janbon, G.; Idnurm, A.; Bahn, Y.S. Cryptococcus neoformans and Cryptococcus gattii, the etiologic agents of cryptococcosis. Cold Spring Harb. Perspect. Med., 2014, 4(7) a019760
Motsei, M.L.; Lindsey, K.L.; Van Staden, J.; Jäger, A.K. Screening of traditionally used South African plants for antifungal activity against Candida albicans. J. Ethnopharmacol., 2003, 86(2-3), 235-241.
[] [PMID: 12738093]
Fesel, P.H.; Zuccaro, A. β-glucan: Crucial component of the fungal cell wall and elusive MAMP in plants. Fungal Genet. Biol., 2016, 90, 53-60.
[] [PMID: 26688467]
Piotrowska, M.; Masek, A. Saccharomyces cerevisiae cell wall components as tools for ochratoxin a decontamination. Toxins (Basel), 2015, 7(4), 1151-1162.
[] [PMID: 25848694]

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Article Details

Year: 2019
Published on: 14 December, 2018
Page: [330 - 340]
Pages: 11
DOI: 10.2174/2210315509666181214154345
Price: $25

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