Antimutagenic Activity of Phenylpropanoids from Clove (Syzygium aromaticum)

Abstract

Phenylpropanoids that possess antimutagenic activity were isolated from the buds of clove (Syzygium aromaticum). The isolated compounds suppressed the expression of the umu gene following the induction of SOS response in the Salmonella typhimurium TA1535/pSK1002 that have been treated with various mutagens. The suppressive compounds were mainly localized in the ethyl acetate extract fraction of the processed clove. This ethyl acetate fraction was further fractionated by silica gel column chromatography, which resulted in the purification and subsequent identification of the suppressive compounds. Electron impact mass spectrometry, IR, and (1)H and (13)C NMR spectroscopy were then used to delineate the structures of the compounds that confer the observed antimutagenic activity. The secondary suppressive compounds were identified as dehydrodieugenol (1) and trans-coniferyl aldehyde (2). When using 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) as the mutagen, compound 1 suppressed 58% of the umu gene expression as compared to the controls at a concentration of 0.60 micromol/mL, with an ID(50) (50% inhibitory dose) value of 0.48 micromol/mL, and compound 2 suppressed 63% of the umu gene expression as compared to the controls at a concentration of 1.20 micromol/mL, with an ID(50) value of 0.76 micromol/mL. Additionally, compounds 1 and 2 were tested for their ability to suppress the mutagenic activity of other well-known mutagens such as 4-nitroquinolin 1-oxide (4NQO) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), which do not require liver metabolizing enzymes, and aflatoxin B(1) (AfB(1)) and 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), which require liver metabolizing enzymes and activated Trp-P-1 and UV irradiation. Compounds 1 and 2 showed dramatic reductions in their mutagenic potential of all of the aforementioned chemicals or treatment. For the search of the structure-activity relationship, the derivatives of 1 and 2 (1a and 2a-c) were also assayed with all mutagens. Finally, the antimutagenic activities of compounds 1, 1a, 2, and 2a-c against furylfuramide, Trp-P-1, and activated Trp-P-1 were assayed by the Ames test using the S. typhimurium TA100 strain.

Isolation, Characterization, Crystal Structure Elucidation of Two Flavanones and Simultaneous RP-HPLC Determination of Five Major Compounds from Syzygium campanulatum Korth

“…The UV-Vis spectra of compounds (1)(2)(3)(4)(5) showed absorption at λmax 330 and 210 nm ( Figure 1). (5) and (E)-2ʹ,4ʹ-dihydroxy-6ʹ-methoxy chalcone (6).…”

“…Figure 3. PCA data can be used to differentiate age of plant with maximum concentration of all compounds (1)(2)(3)(4)(5).…”

“…Crystal data and structure refinement details of compound (1 and 2) is; Formulae: C18H18O4 and C17H16O4, molecular weight: 298 and 284, crystal system: monoclinic, space group: P21 (No. 4).The crystals refinement data of compounds (1 and 2) are shown in Table 1, whereas the selected bond lengths and angles of both compounds (1 and 2) crystallographically are shown in Figures 6 and 7 and are also listed in (Supplementary data, Tables S1-S18). S = Goodness of fit, in general value of S should be close to 1. wR2 = Weighted Residual Factor is the most closely related to the refinement against squared structure factors.…”

“…Therefore mobile phase containing 0. The concentration of each compound (1)(2)(3)(4)(5) in the extracts of different age plants was calculated from the experimental peak areas by interpolation to standard calibration curves (Table 3). Table 3.…”

“…It is widely distributed from Malaysia to north-eastern Australia [1]. It is reported that the genus Syzygium is rich in secondary metabolites such as terpenoids [2,3], phenylpropanoids [4], chalcones [5], flavonoids [6], lignans [7], alkyl phloroglucinols [8], hydrolysable tannins and chromone derivatives [9]. Therapeutically, Syzygium genus is used in the treatment of rheumatism [10], haemorrhage, GIT disorders [11], diabetes [12], inflammation, allergy [13,14], convulsion [15], hypertension [16] and bacterial infections [17].…”