Monday Article #56: Biological properties of the world's most expensive edible mushroom: Truffles

Due to their unique flavour, nutritional value, and potential health benefits, mushrooms are a popular food item in various cuisines. Out of the approximately 200 species of mushrooms consumed by humans, truffles are one of the world’s most expensive mushrooms. There are three main types of truffles, namely black, white, and summer truffles. Depending on the species, quality, supply and demand, truffles can sell for €90 to €5250 (MYR 492 to 28, 689) per kilogram, where white truffles are the most pricey [1].

Besides their distinct flavour profile and aroma that make them a gourmet delicacy in the culinary world, truffles have been found to possess various beneficial biological properties, including antioxidant, antimutagenic, and antimicrobial effects.

Figure 1. An image of a truffle [2].

Antioxidant

White desert truffles (Tirmania nivea) sourced from Middle Eastern countries, including Bahraini, Iran, Morocco, and Saudi Arabia, were assessed for their antioxidant activity using various analytical methods [3]. All four types of the truffles displayed varying degrees of antioxidative abilities, with Iranian truffles scoring the highest in most of the tested parameters. There was also an association of the phenolic content with the antioxidant activity, thus suggesting that phenolics are the main compounds responsible for the truffles’ antioxidant properties.

Polysaccharides isolated from truffles Tuber Aestivum and Tuber Melanosporum were also demonstrated to have antioxidant activities to protect cells from H2O2-induced oxidative damage [4]. Further analysis of Tuber Aestivum polysaccharide revealed that it is able to increase the secretion of antioxidant enzymes, superoxide dismutase and catalase, to thus exert its antioxidant effects. Besides that, extracts of truffle species T. boudieri, T. albiensis, P. juniperii, T. claveryi and P. lefebvrei also possess antioxidant properties, where T. boudieri had the strongest antioxidative ability [5].

Anticancer

Besides their antioxidative properties, various species of truffles have also been found to contain anticancer activities. For example, T. boudieri extracts are able to inhibit the growth of cancer cells, stimulate apoptosis of cancer cells, and suppress formation of new blood vessels that tumours need to grow [6]. In addition, extracts of the desert truffle T. claveryi is able to exert anticancer activities against colon, breast, prostate, and brain cancer cells by stimulating cell apoptosis [7]. Another type of truffle found naturally in Arab deserts, P. lefebvrei, is also able to inhibit proliferation of breast and liver cancer cells [8].

Antimicrobial

Truffles have been demonstrated to contain antimicrobial properties against various microorganisms. A study found that five species of truffles (T. boudieri, T. claveryi, T. albiensis, P. juniperii, and P. lefebvrei) exerted antibacterial activities against various bacteria, including E. coli, S. aureus, and many others [5]. Even fungi, such as Candida albicans, are susceptible to the antimicrobial activities of the truffles. Another two species of truffle, T. magnusii and T. melanosporum, also have an antibacterial effect on S. aureus, while T. gennadii and T. aestivum are active against bacteria S. flexneri and L. monocytogenes respectively [9].

Figure 2. Five different species of truffles [10].

Conclusion

Although the distinctive aroma and nutritional value of truffles are well-known, truffles contain added benefits too, including the properties discussed above. The antioxidant activities give truffles a potential to become an alternative source of natural antioxidants for various industries, such as pharmaceuticals and even cosmetics. Furthermore, the anticancer effects of the fungi provide significant possibilities for the development of a naturally-sourced anticancer drug. The antimicrobial properties of truffles also addresses the problem of antibiotic resistance, reducing the need of chemical synthesised antibiotics. Therefore, the health-benefiting and potentially therapeutic properties of truffles should be appreciated and further studied.

References

[1] Laumont. (2021). What is the price of black truffle? Retrieved from https://laumontshop.uk/blogs/news/what-is-the-price-of-black-truffle

[2] Truff. (n.d.). What are truffles, and what do they taste like? Retrieved from https://www.truff.com/articles/what-are-truffles

[3] Al-Laith, A.A.A. (2010) ‘Antioxidant components and antioxidant/antiradical activities of desert truffle (Tirmania nivea) from various Middle Eastern origins’, Journal of Food Composition and Analysis, 23(1), pp.15-22. [Online] DOI: 10.1016/j.jfca.2009.07.005

[4] Guan, T., Wei, X., Xu, P., Chen, K., Zou, Y., Chen, M. and Zhu, Z. (2022) ‘Comparison of structural and antioxidant activity of polysaccharide extracted from truffles’, Journal of Food Science, 87(7), pp.2999-3012. [Online] DOI: 10.1111/1750-3841.16207

[5] Fidan, M., Ali, M.M., Erez, M.E., Cigerci, I.H., Ozdemir, S. and Sen, F. (2022) ‘Antioxidant, antimicrobial, cytotoxic and protective effects of truffles’, Analytical Biochemistry, 641, p.114566. [Online] DOI: 10.1016/j.ab.2022.114566

[6] Al Obaydi, M.F., Hamed, W.M., Al Kury, L.T. and Talib, W.H. (2020) ‘Terfezia boudieri: a desert truffle with anticancer and immunomodulatory activities’, Frontiers in Nutrition, 7, p.38. [Online] DOI: 10.3389/fnut.2020.00038

[7] Dahham, S.S., Al-Rawi, S.S., Ibrahim, A.H., Majid, A.S.A. and Majid, A.M.S.A. (2018) ‘Antioxidant, anticancer, apoptosis properties and chemical composition of black truffle Terfezia claveryi’, Saudi journal of biological sciences, 25(8), pp.1524-1534. [Online] DOI: 10.1016/j.sjbs.2016.01.031

[8] Elsayed, E.A., Alsahli, F.D., Amr, A.E., El Enshasy, H.A. and Wadaan, M.A. (2019) ‘In vitro anti-proliferative potentials of Phaeangium lefebvrei desert truffle towards MCF-7, HepG2 and L929 cell lines’, Journal of Scientific and Industrial Research, 78(12), pp. 858-862. [Online] Available at: http://nopr.niscpr.res.in/handle/123456789/52215

[9] Tejedor-Calvo, E., Amara, K., Reis, F.S., Barros, L., Martins, A., Calhelha, R.C., Venturini, M.E., Blanco, D., Redondo, D., Marco, P. and Ferreira, I.C. (2021) ‘Chemical composition and evaluation of antioxidant, antimicrobial and antiproliferative activities of Tuber and Terfezia truffles’, Food Research International, 140, p.110071. [Online] DOI: 10.1016/j.foodres.2020.110071

[10] Truffling. (n.d.) About us. Retrieved from https://truffling.it/about-us/

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Article by Phoebe Tee