Table 1.
Lactic acid bacteria strains (n = 13) used in this study.
Fig 1.
DPPH radical scavenging activity.
DPPH radical scavenging activity of the water-soluble (black bars) (WSE), ethyl acetate-soluble (white bars) (ESE), and hexane-soluble (grey bars) (HSE) extracts from raw cladode pulp (raw CP), CP without bacterial inoculum and chemically acidified (CP-CT), and cladode pulp fermented with Lactobacillus plantarum POM1 (POM1), CIL6 (CIL6) and 1MR20 (1MR20), Lactobacillus brevis POM2 (POM2) and POM4 (POM4), Lactobacillus rossiae 2LC8 (2LC8) and Pediococcus pentosaceus CILSWE5 (CILSWE5). Butylatedhydroxytoluene (BHT) was used as positive control. The reaction mixture was prepared by diluting BHT in methanol (hatched bar) or acetone (dotted bar). Data are the means (± SD) of three independent experiments performed in triplicate. Data were subjected to one-way ANOVA; pair-comparison of treatment means was achieved by Tukey’s procedure at P0.05. Bars with different superscript letters differ significantly (P<0.05).
Table 2.
Vitamin C and total carotenoids.
Fig 2.
High Performance Liquid Chromatography (HPLC) profiles of ethyl acetate-soluble extracts (ESE) from cladode pulp (CP) without bacterial inoculum and chemically acidified control (CP-CT) (A) and CP fermented with Lactobacillus plantarum 1MR20 (B). The dashed line refers to the percentages of DPPH radical scavenging activity.
Fig 3.
Nitric oxide (NO) (μM) release by Caco-2/TC7 cells.
Caco-2/TC7 cells were treated for 48 h with water-soluble (WSE), ethyl-acetate (ESE), or hexane-soluble (HSE) extracts (10 mg/ml) from raw cladode pulp (raw CP), CP without bacterial inoculum and chemically acidified (CP-CT) and CP fermented with Lactobacillus plantarum 1MR20 (1MR20) and CIL6 (CIL6), Lactobacillus brevis POM4 (POM4), Lactobacillus rossiae 2LC8 (2LC8) and Pediococcus pentosaceus CILSWE5 (CILSWE5). Furthermore, cells were stimulated with a cytomix solution (TNFα, 100 ng/ml; IL-1β, 5 ng/ml; and INF γ, 200 U/ml). Data are the means (± SD) of three independent experiments performed in triplicate. Data were subjected to one-way ANOVA; pair-comparison of treatment means was achieved by Tukey’s procedure at P0.05. Bars with different superscript letters differ significantly (P<0.05).
Fig 4.
Transepithelial electric resistance (TEER) (Ohms x cm2) of Caco-2/TC7 cells.
Caco-2/TC7 cells were incubated 24 h with IL-1β (25 ng/ml) and water-soluble (WSE), ethyl-acetate (ESE), and hexane-soluble (HSE) extracts (10 mg/ml) from raw cladode pulp (raw CP), CP without bacterial inoculum and chemically acidified (CP-CT) and CP fermented with Lactobacillus plantarum 1MR20 (1MR20) and CIL6 (CIL6), Lactobacillus brevis POM4 (POM4), Lactobacillus rossiae 2LC8 (2LC8) and Pediococcus pentosaceus CILSWE5 (CILSWE5). Data are the means (± SD) of three independent experiments performed in triplicate. Data were subjected to one-way ANOVA; pair-comparison of treatment means was achieved by Tukey’s procedure at P0.05. Bars with different superscript letters differ significantly (P<0.05).
Fig 5.
Interleukin-8 (IL-8) (A) and tumour necrosis alfa (TNFα) (B) release by Caco-2/TC7 cells. Caco-2/TC7 cells were stimulated for 24 h with interferon-gamma (INF-γ) (2 ng/mL) and subsequently treated with water-soluble (WSE), ethyl-acetate (ESE), or hexane-soluble (HSE) extracts (10 mg/ml) from raw cladode pulp (raw CP), CP without bacterial inoculum and chemically acidified (CP-CT) and CP fermented with Lactobacillus plantarum 1MR20 (1MR20) and CIL6 (CIL6), Lactobacillus brevis POM4 (POM4), Lactobacillus rossiae 2LC8 (2LC8) and Pediococcus pentosaceus CILSWE5 (CILSWE5). Data are the means (± SD) of three independent experiments performed in triplicate. Data were subjected to one-way ANOVA; pair-comparison of treatment means was achieved by Tukey’s procedure at P0.05. Bars with different superscript letters differ significantly (P<0.05).
Fig 6.
Intracellular reactive oxygen species (ROS) (fluorescence intensity units, Fi) (A) and Prostaglandin E2 (PGE2) (pg/ml) (B) on Caco-2/TC7 cells. Caco-2/TC7 cells were stimulated for 24 h at 37°C with IL-1β (25 ng/mL) and then treated for other 24 h with water-soluble (WSE), ethyl-acetate (ESE), or hexane-soluble (HSE) extracts (10 mg/ml) from raw cladode pulp (raw CP), CP without bacterial inoculum and chemically acidified (CP-CT) and CP fermented with Lactobacillus plantarum 1MR20 (1MR20) and CIL6 (CIL6), Lactobacillus brevis POM4 (POM4), Lactobacillus rossiae 2LC8 (2LC8) and Pediococcus pentosaceus CILSWE5 (CILSWE5). Only the best performing strains and representative species were considered. Data are the means (± SD) of three independent experiments performed in triplicate. Data were subjected to one-way ANOVA; pair-comparison of treatment means was achieved by Tukey’s procedure at P0.05. Bars with different superscript letters differ significantly (P<0.05).
Fig 7.
Permutation analysis of compositional and functional profiles.
Permutation analysis of compositional [vitamin C, total carotenoids, γ-amino butyric acid (GABA), kaemferol, and isorhamnetin], and functional [antioxidant activity, nitric oxide release, tumour necrosis alfa (TNFα), reactive oxygen species (ROS), transepithelial electric resistance (TEER), Prostaglandin E2 (PGE2), and interleukin-8 (IL-8)] profiles of raw cladode pulp (CP), CP without bacterial inoculum and chemically acidified (CP-CT), and fermented CP with Lactobacillus plantarum 1MR20 (1MR20) and CIL6 (CIL6), Lactobacillus brevis POM4 (POM4), Lactobacillus rossiae 2LC8 (2LC8) and Pediococcus pentosaceus CILSWE5 (CILSWE5). Differences are represented colorimetrically with red and green indicating the highest and lowest values of the standardized data, respectively, for each parameter. All data were shown as a percentage of dissimilarity using Euclidean distance.