Critical Reviews in Biotechnology ISSN: 0738-8551 (Print) 1549-7801 (Online) Journal homepage: http://www.tandfonline.com/loi/ibty20 A review on the nucleic acid constituents in mushrooms: nucleobases, nucleosides and nucleotides Chia-Wei Phan, Joon-Keong Wang, Shiau-Chuen Cheah, Murali Naidu, Pamela David & Vikineswary Sabaratnam To cite this article: Chia-Wei Phan, Joon-Keong Wang, Shiau-Chuen Cheah, Murali Naidu, Pamela David & Vikineswary Sabaratnam (2017): A review on the nucleic acid constituents in mushrooms: nucleobases, nucleosides and nucleotides, Critical Reviews in Biotechnology, DOI: 10.1080/07388551.2017.1399102 To link to this article: http://dx.doi.org/10.1080/07388551.2017.1399102 Published online: 10 Nov 2017. Submit your article to this journal View related articles View Crossmark data Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ibty20 Download by: [University of Florida] Date: 11 November 2017, At: 02:55 CRITICAL REVIEWS IN BIOTECHNOLOGY, 2017 https://doi.org/10.1080/07388551.2017.1399102 REVIEW ARTICLE A review on the nucleic acid constituents in mushrooms: nucleobases, nucleosides and nucleotides Chia-Wei Phana,b , Joon-Keong Wangc, Shiau-Chuen Cheahc, Murali Naidua,b, Pamela Davida,b and Vikineswary Sabaratnama,d aMushroom Research Centre, University of Malaya, Kuala Lumpur, Malaysia; bDepartment of Anatomy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; cFaculty of Medicine and Health Sciences, UCSI University, Kuala Lumpur, Malaysia; dInstitute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia ABSTRACT ARTICLE HISTORY Mushrooms have become increasingly important as a reliable food source. They have also been Received 19 March 2017 recognized as an important source of bioactive compounds of high nutritional and medicinal val- Revised 14 October 2017 ues. The nucleobases, nucleosides and nucleotides found in mushrooms play important roles in Accepted 24 October 2017 the regulation of various physiological processes in the human body via the purinergic and/or 0 pyrimidine receptors. Cordycepin, a 3 -deoxyadenosine found in Cordyceps sinensis has received KEYWORDS much attention as it possesses many medicinal values including anticancer properties. In this Mushroom; nucleic acid; review, we provide a broad overview of the distribution of purine nucleobases (adenine and nucleobase; nucleoside; guanine); pyrimidine nucleobases (cytosine, uracil, and thymine); nucleosides (uridine, guanosine, cordycepin; 50-nucleotides; adenosine and cytidine); as well as novel nucleosides/tides in edible and nonedible mushrooms. flavor This review also discusses the latest research focusing on the successes, challenges, and future perspectives of the analytical methods used to determine nucleic acid constituents in mush- rooms. Besides, the exotic taste and flavor of edible mushrooms are attributed to several non- volatile and water-soluble substances, including the 50-nucleotides. Therefore, we also discuss the total flavor 50-nucleotides: 50-guanosine monophosphate (50-GMP), 50-inosine monophosphate (50-IMP), and 50-xanthosine monophosphate (50-XMP) in edible mushrooms. Introduction nucleosides present in mushrooms. In fact, nucleosides are thought to be the main bioactive compounds in the Mushrooms are macrofungi with large, easily observed mushroom Cordyceps (Sordariomycetes), a famous trad- and collectable fruiting bodies. There are more than itional Chinese medicine with high medicinal and com- 14,000 species of mushrooms and at least 2000 of them mercial value [10]. Nucleosides consist of a nucleobase are edible [1]. Out of these 2000 edible mushrooms, approximately 200 are wild species [1]. Mushrooms (also termed as a nitrogenous base) and a 5-carbon have been appreciated for their flavor and texture and sugar (either ribose or deoxyribose). On the other hand, Downloaded by [University of Florida] at 02:55 11 November 2017 are recognized as important sources of nutrients [2–4]. a nucleotide is composed of a nucleoside (a nucleobase The nutritional value of edible mushrooms is due to their and a 5-carbon sugar), in addition with one or more high protein, fiber, vitamin, mineral contents and low fat phosphate group (Figure 1). levels [5]. Culinary mushrooms are also very useful for To date, nucleosides, such as cytidine, uridine, vegetarian diets because they provide many of the essen- adenosine, guanosine, thymidine and inosine, were tial amino acids for adult requirements. More importantly, reported to be involved in the regulation and modula- edible mushrooms contain many different bioactive com- tion of various physiological processes in the human pounds including polysaccharides, steroids, phenols, ter- body via the purinergic and/or pyrimidine receptors penoids, and nucleosides, all of which have been shown to [11]. These nucleosides serve as precursor molecules for exert various human health benefits [6]. making DNA and RNA which are vital in almost all cellu- While the health effects and underlying mechanisms lar functions. Furthermore, nucleosides and/or nucleoti- of mushroom polysaccharides have been more exten- des were reported to enhance brain function, affect sively evaluated [7–9], little attention was paid to the immune modulation, influence fatty acids metabolism, CONTACT Chia-Wei Phan [email protected] Department of Anatomy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; Vikineswary Sabaratnam [email protected] Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia ß 2017 Informa UK Limited, trading as Taylor & Francis Group 2 C.-W. PHAN ET AL. chromatography (RPLC), hydrophilic interaction chroma- tography (HILIC), ion-exchange chromatography (IEC) and denaturing HPLC (DHPLC). Electrophoretic methods encompass CE and capillary electrochromatography (CEC). Capillary electrophoresis with ultraviolet (UV) and/or mass spectrometry (MS) detection has been widely used in the food industry for analysis of nucleosides and nucleotides. In fact, due to the high polarity of nucleotides, an ion-pairing agent or Figure 1. The composition of a nucleotide which comprised an ion-exchange column is required for analysis by of a nucleoside (a nucleobase and 5-carbon sugar) and one or HPLC. more phosphate group. contribute to iron absorption in the gut, and improve Nucleobases, nucleosides and nucleotides in gastrointestinal tract repair after damage [12,13]. Ganoderma spp It is noteworthy to highlight that even though Ganoderma spp belong to the family Polyporaceae and healthy people can produce and recycle nucleosides in are one of the most important medicinal fungi of their bodies, dietary nucleosides sourced from nucleo- Basidiomycetes. Ganoderma spp, in particular tide-rich food can be useful to meet the demand for Ganoderma lucidum (Curtis) P. Karst, has a long history nucleosides in situations like illness recovery or immune of use for promoting health and longevity [20]. system malfunction. Due to the remarkable reservoir of Ganoderma lucidum is called Reishi in the Japanese lan- nucleosides in mushrooms, scientists have recently guage and Lingzhi in Chinese. The first isolation of found the urge to qualitatively and quantitatively deter- adenine, adenosine, uracil and uridine from Ganoderma mine the distribution of nucleosides in mushrooms [14]. species was carried out by Yu and Zhai in 1979 on Figure 2 shows the chemical structures of different Ganoderma capense (Lloyd) Teng [21]. Ganoderma nucleobases and nucleosides reported in mushrooms. capense is a Ganoderma species that morphologically This paper mainly summarizes the types of nucleo- sides and nucleotides found in mushrooms and the resembles G. lucidum to a certain extent [22,23]. analytical methods employed to identify and quantify According to Yu and Zhai [21], mycelia from G. lucidum – them. In addition, newly discovered mushroom nucleo- were extracted with 92 95% ethanol followed by sus- sides and their total flavor nucleotides are also pension in water and further extracted with ethyl ether. reviewed. The resulting aqueous solution was subjected to ion- exchange chromatography to give a neutral and basic fractions. Upon subfractioning, the neutral fraction Mode of detection of nucleobases, nucleosides yielded uracil and uridine via adsorption chromatog- and nucleotides raphy on macroporous resin. The basic fraction, on the Novel analytical and detection methods play an essen- other hand, yielded adenine and adenosine by further Downloaded by [University of Florida] at 02:55 11 November 2017 tial role in biotechnology. Further progress in biotech- extraction with chloroform and butanol. nology very much depends on the introduction of A study of Ganoderma nucleotides was subsequently 0 increasingly sophisticated analytical tools for the separ- carried out by Kim et al. [24]. According to the study, 5 - 0 0 ation, characterization and quantitation of natural prod- guanosine monophosphate (5 -GMP) and 5 -xanthosine ucts. Consequently, the concepts, methods and monophosphate (5’-XMP) were found in both young strategies of “analytical chemistry” will inevitably be and mature basidiocarps. However, the levels of both adopted by biotechnology. the nucleotides in the young basidiocarp were higher Separations of nucleobases, nucleosides and nucleo- than those in the matured basidiocarp. Adenosine iso- tides have been accomplished by two general methods: