The efficacy of edible film from Konjac glucomannan and saffron petal extract to improve shelf life of fresh‐cut cucumber

Abstract The efficacy of saffron petal extract (SPE; 1%–4%) incorporated into Konjac glucomannan (KGM) edible films on the quality and shelf life of fresh‐cut cucumbers was evaluated. Changes in chemical, physical, and microbial properties, antioxidant activity, and total soluble phenolic contents of sliced cucumbers during storage at 4°C for 5 days were investigated. Results showed that the addition of SPE markedly reduced the water vapor permeability features of produced films, whereas the moisture content and transparency of them increased (p < .05). All the formulated films containing 1%–4% of SPE exhibited significant antimicrobial properties against the examined pathogens (Escherichia coli, Shigella sonnei, Salmonella Typhi, Staphylococcus aureus, and Bacillus cereus) both in vitro and in vivo conditions. KGM films incorporated SPE were successful in reducing mesophilic bacteria and fungi populations so that the microbial load significantly decreased as the concentrations of SPE increased and KGM + 4% of SPE was considered as the most effective treatment in decreasing the microbial content of sliced cucumbers. Total soluble solids of the treated cucumbers were significantly increased at the end of the storage in refrigerator, compared to the control sample. Moreover, antioxidant activity (DPPH assay) and total soluble phenols in treated fruit increased with storage time, while these parameters decreased with increasing concentrations of SPE incorporated into KGM film. So according to the findings, the introduced film with KGM and SPE could be considered as an edible film and be applied to preserve the fruit and vegetables quality and extend the shelf life of sliced cucumbers

Pure and Co-Fermentation of Quinoa Seeds by <i>Limosilactobacillus fermentum</i> and <i>Lacticaseibacillus rhamnosus</i>: Bioactive Content, Antidiabetic and Antioxidant Activities

In this study, Limosilactobacillus fermentum PTCC 1638 and Lacticaseibacillus rhamnosus PTCC 1637 were used alone and in combination to ferment quinoa seeds, and the effect of fermentation (37 °C; 24 h) on the pH, total phenols, tocopherols, vitamin C, antioxidant activity, and enzymes inhibition (α-amylase and α-glucosidase; antidiabetic effect) was investigated. The results showed that with the increase in the fermentation time, the bacterial population, total phenols, antioxidant activity, and enzymes inhibition increased, which showed the greatest increase for the co-culture of L. rhamnosus and L. fermentum compared to the pure culture of each strain. Due to the increase in the fermentation time, the tocopherol isomers (α, β, γ, and δ), vitamin C, and pH decreased, and the largest decrease was related to the co-culture of the strains, followed by L. rhamnosus and L. fermentum. The results of this study showed that the co-culture and pure culture of bacteria can have different effects on the physicochemical properties and bioactive compounds of quinoa seeds

Ultrasound-Assisted Lactic Acid Fermentation of Bakraei (<i>Citrus reticulata</i> cv. Bakraei) Juice: Physicochemical and Bioactive Properties

In this study, ultrasonication (US) (50 W, 30 kHz, 1–6 min) was used to increase the efficiency of Limosilactobacillus reuteri PTCC 1655 fermentation process (37 °C; 30 h) of Bakraei juice. Total sugars, pH, Brix, organic acids, vitamin C, polyphenols, antioxidant activity, α-amylase inhibition and anti-inflammatory properties were measured during the fermentation period. The results showed that by increasing the ultrasound time up to 5 min, pH, vitamin C, citric acid, and polyphenolic compounds decreased, while lactic acid, antioxidant capacity, α-amylase inhibition and anti-inflammatory properties were increased. When the ultrasound time was increased up to 6 min, compared to the non-ultrasound-treated sample, the efficiency of the fermentation process decreased and promoted a decrease in the microbial population, lactic acid levels, antioxidant activity, α-amylase inhibition, and anti-inflammatory properties of the juices. The initial anti-inflammatory activity (11.3%) of juice reached values of 33.4% and 19.5%, after US treatments of 5 and 6 min, respectively, compared to the non-sonicated juice (21.7%), after 30 h of fermentation. As a result, the use of ultrasound in the controlled fermentation process can increase the efficiency of fermentation process

Protective effects of synbiotic diets of Bacillus coagulans, Lactobacillus plantarum and inulin against acute cadmium toxicity in rats

Abstract Background Cadmium is a heavy metal that causes oxidative stress and has toxic effects in humans. The aim of this study was to investigate the influence of two probiotics along with a prebiotic in preventing the toxic effects of cadmium in rats. Methods Twenty-four male Wistar rats were randomly divided into four groups namely control, cadmium only, cadmium along with Lactobacillus plantarum (1 × 109 CFU/day) and inulin (5% of feedstuff) and cadmium along with Bacillus coagulans (1 × 109 spore/day) and inulin (5% of feedstuff). Cadmium treated groups received 200 μg/rat/day CdCl2 administered by gavage. During the 42-day experimental period, they were weighed weekly. For evaluation of changes in oxidative stress, the levels of some biochemicals and enzymes of serum including SOD, GPX, MDA, AST, ALT, total bilirubin, BUN and creatinine, and also SOD level of livers were measured at day 21 and 42 of treatment. The cadmium content of kidney and liver was determined by using atomic absorption mass spectrophotometry. Data were analyzed using analysis of variance (ANOVA) followed by Duncan’s post hoc test. Results Treatment of cadmium induced rats with synbiotic diets significantly improved the liver enzymes and biochemical parameters that decreased AST, ALT, total bilirubin, BUN and metal accumulation in the liver and kidney and increased body weight, serum and liver SOD values in comparison with the cadmium-treated group. No significant differences were observed with MDA and GPX values between all groups (p > 0.05). Conclusions This study showed that synbiotic diets containing probiotics (L. plantarum and B. coagulans) in combination with the prebiotic (inulin) can reduce the level of cadmium in the liver and kidney, preventing their damage and recover antioxidant enzymes in acute cadmium poisoning in rat

Additional file 1: of Protective effects of synbiotic diets of Bacillus coagulans, Lactobacillus plantarum and inulin against acute cadmium toxicity in rats

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