Ponceau 4R (Acid Red 18)

Ponceau 4R (Acid Red 18) is a synthetic colorant used as a food colorant^[1]. Ponceau 4R is a strawberry red azo dye, usually synthesized from aromatic hydrocarbons, stable to light, heat and acid, but fades in the presence of ascorbic acid^[2]. Ponceau 4R has antibacterial activity against both Gram-positive and Gram-negative bacteria^[3]. The weak resonance light scattering intensity of Ponceau 4R can be greatly enhanced in the presence of protein^[4].

In vitro, treatment of B cells permeabilized with localized plasma membrane (PM) with Ponceau 4R (1mM) for 10min rapidly quenched the fluorescence of B cells labeled with carboxyfluorescein succinimidyl ester (CFSE)^[5].

In vivo, oral administration of Ponceau 4R (4g/kg) to Wistar albino rats for 45 days significantly increased serum urea concentration, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, and led to vacuolar degeneration in the liver and tubular degeneration in the kidneys^[6].

References:
[1] EFSA Panel on Food Additives and Nutrient Sources Added to Food. Scientific Opinion on the re‐evaluation of Ponceau 4R (E 124) as a food additive[J]. EFSA Journal, 2009, 7(11): 1328.
[2] Scotter M J, Castle L. Chemical interactions between additives in foodstuffs: a review[J]. Food additives and contaminants, 2004, 21(2): 93-124.
[3] Zangeneh Monfared F, Shahabadi N, Mahmoudi Hashemi M, et al. Studies of Ponceau 4R food colorant and zinc oxide nanoparticles containing it interactions with DNA and evaluation of their antimicrobial activity[J]. Journal of Food Processing and Preservation, 2022, 46(2): e16222.
[4] Zhong H, Xu J J, Chen H Y. A rapid and sensitive method for the determination of trace proteins based on the interaction between proteins and Ponceau 4R[J]. Talanta, 2005, 67(4): 749-754.
[5] Maeda F Y, van Haaren J J H, Langley D B, et al. Surface-associated antigen induces permeabilization of primary mouse B-cells and lysosome exocytosis facilitating antigen uptake and presentation to T-cells[J]. Elife, 2021, 10: e66984.
[6] Al-Dahhan M A H, Al-Samawy E R M, Al-Kaisei B I, et al. Effect of synthetic colorants (Sunset yellow and Ponceau 4R) in some biochemical and histopathological parameters of albino rats[J]. Med. Sci, 2014, 13(1).

Ponceau 4R (Acid Red 18)是一种合成着色剂，可用作食用色素^[1]。Ponceau 4R是一种草莓红偶氮染料，通常由芳香烃合成，对光、热和酸稳定，但在抗坏血酸存在下褪色^[2]。Ponceau 4R具有抗菌活性，对革兰氏阳性菌和革兰氏阴性菌均有效^[3]。Ponceau 4R的弱共振光散射强度在蛋白质存在下能够大大增强^[4]。

在体外，Ponceau 4R（1mM）处理局部质膜（PM）透化的B细胞10min，迅速淬灭了羧基荧光素琥珀酰亚胺酯（CFSE）标记的B细胞的荧光^[5]。

在体内，Ponceau 4R（4g/kg）通过口服处理Wistar白化大鼠45天，显著升高了血清尿素浓度，天冬氨酸氨基转移酶（AST）和丙氨酸氨基转移酶（ALT）水平，导致了肝脏呈空泡变性，肾脏呈小管变性^[6]。