Degradation of Methyldopa by Banana

Abstract

Methyldopa, an antihypertensive, is a very close analogue of DOPA. Drug interaction accompanied by degradation in a banana juice mixture was reported for DOPA. However, the effect of banana on methyldopa has not been reported. Therefore, we have investigated the impact of banana juice on methyldopa. The drug and supernatant of banana pulp were mixed, and the mixture was observed for changes in color, drug concentration, and ultraviolet-visible absorption spectra at 30 °C. The originally clear and colorless mixture started to acquire a yellow coloration after about 30 seconds after the mixing. The color tone increasingly deepened, then blistered solid particles that do not dissolve were observed after 3 hours. Concentration of methyldopa in the mixture decreased by 60% after 5 min, to 0.5% after 30 min of the mixing. From these findings, it was suggested that the drastic alterations were caused by banana polyphenol oxidase that plays a role in the biosynthesis of melanin pigment from levodopa in banana pulp. Because the degradation of methyldopa occurs extremely fast, it was suggested concomitant use of this anti-hypertensive and banana juice consumption should be avoided in clinical practice.

Pharmacokinetic Interactions of Antihypertensive Drugs with Citrus Juices

“…We believed that studies with such a wide deviation should be integrated (Uesawa, 2011b). Amlodipine, efonidipine, manidipine, felodipine, nifedipine, and nisoldipine were mentioned in 2 reports (Josefsson et al, 1996;Vincent, 2000), 3 reports (Mimura, 1998(Mimura, , 2000Yajima et al, 2003), 2 reports (Sugawara, 1996;Uno, 2006), 12 reports (Bailey et al, 1991(Bailey et al, , 1993a(Bailey et al, , 1998Edgar, 1992;Bailey, 1995Bailey, , 1996Bailey, , 2000Bailey, , 2003Lundahl, 1995Lundahl, , 1997Lown et al, 1997;Goosen et al, 2004), 6 reports (Bailey et al, 1991, 1993aRashid, 1993Rashid, , 1995Sigusch, 1994;Azuma, 1996;Ohtani, 2002), and 4 reports (Bailey et al, 1993a, b;Azuma et al, 1996;Takanaga, 2000;Ohtani et al, 2002), respectively (Table 1).…”

“…This table was cited from the literature (Uesawa et al, 2011b WMD and the 95% CI were calculated by the general variance-based method. This figure was cited from the literature (Uesawa et al, 2011b). WMD and the 95% CI were calculated by the general variance-based method.…”

“…WMD and the 95% CI were calculated by the general variance-based method. This figure was cited from the literature (Uesawa et al, 2011b). Fig.…”

Methyldopa electrochemical sensor based on a glassy carbon electrode modified with Cu/TiO2 nanocomposite

“…1,2 It is a structural analogue of dopa (dihydroxyphenyl alanine), an anti-Parkinsonism medication; in fact it has an amino acid skeleton with a catechol group and a methyl group on the α-carbon of the side chain. [3][4][5][6] Methyldopa operates through the biotransformation to methyl norepinephrine in the adrenergic nerve terminals. 7 Inhibition of the aromatic amino acid decarboxylase (DOPA decarboxylase) may be one of its functions, this enzyme acts in the biosynthetic pathway of catecholamine's, 8 and converts l-DOPA to the dopamine precursor of epinephrine and norepinephrine.…”

Bananas decrease acetaminophen potency in in vitro assays

“…Interestingly, banana pulp contains polyphenol oxidase [ 1 ], which rapidly converts catechols with two phenolic hydroxyl groups in the ortho- position into melanin precursors. Thus, banana components have been shown to interact and attenuate the actions of catecholic medications such as levodopa and reduce drug bioavailability and efficacy [ 2 , 3 ].…”