AMA 10th edition
In-text citation: (1), (2), (3), etc.
Reference: Kurniawan R, Hermawati E, Hertadi R, et al. Intermolecular [4+2]-cycloaddition reaction to biotransform morachalcone A into kuwanon J, catalyzed by Diels-Alderase from a root culture of Morus alba var. shalun (M. shalun). Eurasia J Biosci. 2020;14(1), 983-989.

APA 6th edition
In-text citation: (Kurniawan et al., 2020)
Reference: Kurniawan, R., Hermawati, E., Hertadi, R., Abe, I., Morita, H., Cing Piow, W., & Hakim, E. H. (2020). Intermolecular [4+2]-cycloaddition reaction to biotransform morachalcone A into kuwanon J, catalyzed by Diels-Alderase from a root culture of Morus alba var. shalun (M. shalun). Eurasian Journal of Biosciences, 14(1), 983-989.

Chicago
In-text citation: (Kurniawan et al., 2020)
Reference: Kurniawan, Rahmat, Elvira Hermawati, Rukman Hertadi, Ikuro Abe, Hiroyuki Morita, Wong Cing Piow, and Euis H. Hakim. "Intermolecular [4+2]-cycloaddition reaction to biotransform morachalcone A into kuwanon J, catalyzed by Diels-Alderase from a root culture of Morus alba var. shalun (M. shalun)". Eurasian Journal of Biosciences 2020 14 no. 1 (2020): 983-989.

Harvard
In-text citation: (Kurniawan et al., 2020)
Reference: Kurniawan, R., Hermawati, E., Hertadi, R., Abe, I., Morita, H., Cing Piow, W., and Hakim, E. H. (2020). Intermolecular [4+2]-cycloaddition reaction to biotransform morachalcone A into kuwanon J, catalyzed by Diels-Alderase from a root culture of Morus alba var. shalun (M. shalun). Eurasian Journal of Biosciences, 14(1), pp. 983-989.

MLA
In-text citation: (Kurniawan et al., 2020)
Reference: Kurniawan, Rahmat et al. "Intermolecular [4+2]-cycloaddition reaction to biotransform morachalcone A into kuwanon J, catalyzed by Diels-Alderase from a root culture of Morus alba var. shalun (M. shalun)". Eurasian Journal of Biosciences, vol. 14, no. 1, 2020, pp. 983-989.

Vancouver
In-text citation: (1), (2), (3), etc.
Reference: Kurniawan R, Hermawati E, Hertadi R, Abe I, Morita H, Cing Piow W, et al. Intermolecular [4+2]-cycloaddition reaction to biotransform morachalcone A into kuwanon J, catalyzed by Diels-Alderase from a root culture of Morus alba var. shalun (M. shalun). Eurasia J Biosci. 2020;14(1):983-9.

Abstract

Morus is one of the main genera of the Moraceae family and widely cultivated in Southeast Asia for silkworm feeding. This genus also produces valuable bioactive phenolic compounds such as flavonoids, stilbenes, 2-arylbenzofurans, and Diels-Alder adducts. Previous phytochemical investigation of Morus shalun reported the Diels-Alder adducts as the mayor phenolic compounds isolated from root cultures. The Diels-Alder adduct is considered formed by the intermolecular [4+2]-cycloaddition between a diene of dehydroprenyl phenol with a dienophile of the α, β-unsaturated carbonyl group of a chalcone. This reaction in plant tissues is naturally catalyzed by the enzyme Diels-Alderase. The experiment was designed to determine the existence of Diels-Alderase isolated from a root culture of M. shalun by evaluating its activity in the biotransformation process of morachalcone A to produce kuwanon J. Biotransformation was detected using HPLC and LCMS. Kuwanon J showed significantly higher cytotoxic activities against the three human cancer cell lines HeLa, A459, and MCF7 compared with morachalcone A.

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