Evidence and hypotheses on adverse effects of the food additives carrageenan (E 407)/processed Eucheuma seaweed (E 407a) and carboxymethylcellulose (E 466) on the intestines: a scoping review

Influence of consumption of the food additive carrageenan on the gut microbiota and the intestinal homeostasis of mice

“…Regarding the adverse effects of CGN observed in our study (Tables 1, 4 and S1†), an extensive body of evidence explains the damage as being related to CGN degradation to low molecular weight (average 20 to 30 kDa) compounds, 25,27,30 which have demonstrated mainly inflammatory effects along with decreasing barrier function and/or increasing permeability. 35 In previous studies, 15 we have observed that the same CGN brand supplied to the mice, evaluated at values as high as 3 mg mL −1 , did not have any impact either on Caco-2 cell viability or on the epithelial monolayer integrity; however, hydrolysed CGN (heated at 121 °C for 15 min at pH < 2) decreased cellular viability and increased epithelial permeability at an IC 50 value of 0.1 mg mL −1 . The results in Table 4, showing that the fecal content of mice fed CGN increased the cytotoxicity towards Caco-2, would indicate some degree of CGN hydrolysis through intestinal transit and/or degradation by the gut microbiota.…”

“…A scoping review on the gut effects of the food additive CGN 35 and other recent reports 36,37 state, as hallmark conclusions, the importance of addressing the interaction of the additive with the gut microbiome. Our results show that adverse effects, such as reduced animal weight and lowered immune functions (Tables 1 and S1†), were observed in spite of non-significant microbiota taxonomical changes associated with CGN intake (Table 2).…”

“…21 Considering that degraded CGN is used as an experimental inflammation model, similar to the dextran sulfate sodium (DSS) colitis model, 45 the potential hydrolysis of CGN by the gut microbiota could have favored the damage caused by low- M w CGN products to the intestinal barrier permeability. 35 The sulfate groups from the polygalactan could facilitate disturbing the intestinal mucus layer by making it more permeable to gut microbiota that reach the epithelial cells and trigger an inflammatory reaction. 46 Thus, a correlation between mouse fecal cytotoxicity and altered leukocyte function parameters, such as the proliferative capacity of lymphocytes stimulated by ConA and the macrophage phagocytic efficiency, was detected in the present study (Fig.…”

A 28-Day Repeated Oral Administration Study of Mechanically Fibrillated Cellulose Nanofibers According to OECD TG407

“…It is possible that the effect of fib-CNF on intestinal bacteria led to weight loss. Numerous studies and review articles discuss the degradation of cellulose and other dietary fibers by intestinal bacteria [24][25][26][27][28][29][30][31][32][33][34]. Although cellulose is a central component of plant fiber and is abundant in diets with plant-derived foods, humans, like other mammals, rely on gut microbiota to break down cellulose.…”