Novel Bio-Functional Aloe vera Beverages Fermented by Probiotic Enterococcus faecium and Lactobacillus lactis

Aloe Barbadensis Miller (Aloe Vera)

Aloe Barbadensis Miller (Aloe Vera, AV) is a widely recognized for its diverse health-promoting, skin care, and medicinal properties. This narrative review provides a comprehensive overview of AV's bioactive compounds, pharmacological activities, potential applications, its toxic and adverse effects, as well as the clinical evidence supporting AV's efficacy in disease prevention. AV contains over 200 bioactive compounds, with the inner clear gel of the leaves containing the majority of these compounds. These include phenolic acids (274.5-307.5 mg/100 g), flavonoids. (3.63-4.70 g/kg), polysaccharides (3.82-6.55 g/kg), saponins, alkaloids, terpenoids, and anthraquinone derivatives. Findings from clinical studies involving both humans and animals highlight the therapeutic potential of AV across diverse health domains. The studies demonstrate AV's efficacy in reducing blood glucose levels, exhibiting antioxidant and immunomodulatory effects, inducing apoptosis in cancer cells, protecting the liver from damage, and displaying antimicrobial properties. In the fields of dermatology and dentistry, AV has also been observed to promote skin and oral health. However, it is imperative to acknowledge potential risks, adhere to recommended dosages, and seek guidance from healthcare experts before employing AV as a natural therapeutic option. Moreover, considering safety concerns, further well-designed randomized controlled trials are necessary to substantiate the potential benefits of AV and comprehensively assess any associated risks.

Enterococcus faecium from chicken feces improves chicken immune response and alleviates Salmonella infections: a pilot study

Probiotics reduce the emergence of antibiotic resistance in the livestock industry. Chicken feces are reservoirs of beneficial microbiomes. The aim of this study was to isolate putative probiotics from the intestinal contents of broiler chickens. Five fecal samples were collected from two poultry farms in Al-Ahsa, Saudi Arabia. Of the 11 morphologically distinct isolates from chicken feces (CF) samples, five isolates displayed positive reactions to Gram staining, catalase, and oxidase tests, and reacted negatively to a hemolytic assay. The isolates CF1, CF2, CF3, CF8, and CF11 were selected for further analysis of probiotic characterization, gastric survival capacity, antibiotic susceptibility, and antimicrobial activity against poultry infected with Salmonella enterica. CF2 and CF11 showed the highest hydrophobic values (> 51% hydrophobic nature). CF1, CF2, and CF11 showed potent antimicrobial activities. The active isolate CF2 was identified as Enterococcus faecium by 16s rRNA sequencing and showed a genetic similarity of 99.1%. An in vivo study was conducted using a chicken model. Enterococcus faecium-fed chickens showed an improved body weight and a lower mortality rate (17-34%). Salmonella enterica colony-forming unit (CFU) invasion in the spleen and thymus was significantly reduced in the E. faecium-fed chickens. The fecal S. enterica load was reduced from CFU 6.8 to 3.9/g in oral-administered E. faecium-fed chickens. Enterococcus faecium-fed chickens showed increased levels (P < 0.01) of butyric acid and reduced levels (P < 0.01) of intestinal interleukin 1 beta, C-reactive protein, and interferon gamma levels compared to those in the S. enterica-infected chicken group. In addition, E. faecium showed significant binding to Caco-2 epithelial cells in vitro and inhibited S. enterica colonization, indicating co-aggregation of E. faecium in epithelial cells. These results revealed that an E. faecium formulation could prevent bacterial infection and improve the quality of broiler chickens.

Biodegradation of Punicalagin into Ellagic Acid by Selected Probiotic Bacteria: A Study of the Underlying Mechanisms by MS-Based Proteomics

Pomegranate (Punica granatum L.) is a well-known source of bioactive phenolic compounds such as ellagitannins, anthocyanins, and flavanols. Punicalagin, one of the main constituents of pomegranate, needs to be biodegraded by bacteria to yield metabolites of medicinal interest. In this work, we tested 30 lactic acid bacteria (LAB) and their capacity to transform punicalagin from a punicalagin-rich pomegranate extract into smaller bioactive molecules, namely, ellagic acid and urolithins. These were identified and quantified by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS²). Further, we evaluated the molecular mechanism governing this transformation through label-free comparative MS-based proteomics. All tested LAB strains were capable of transforming punicalagin into ellagic acid, while the biosynthesis of urolithins was not observed. Proteomic analysis revealed an increase of generic transglycosylases that might have a hydrolytic role in the target phenolic molecule, coupled with an increase in the quantity of ATP-binding cassette (ABC) transporters, which might play a relevant role in transporting the resulting byproducts in and out of the cell.

Effect of Gastrointestinal Digestion on the Bioaccessibility of Phenolic Compounds and Antioxidant Activity of Fermented Aloe vera Juices

Plant-based beverages are enriched by the fermentation process. However, their biocompounds are transformed during gastrointestinal digestion, improving their bioaccessibility, which is of primary importance when considering the associated health benefits. This study aimed to evaluate the effect of in vitro gastrointestinal digestion on phenolic compound bioaccessibility and antioxidant activity of novel Aloe vera juices fermented by probiotic Enterococcus faecium and Lactococcus lactis. Aloe vera juices were digested using the standardized static INFOGEST protocol. During digestion, phenolic compounds and antioxidant activity (DPPH, ABTS, and FRAP) were accessed. The digestion process was seen to significantly increase the total phenolic content of the fermented Aloe vera juices. The fermentation of Aloe vera increased the bioaccessibility of juice biocompounds, particularly for kaempferol, ellagic acid, resveratrol, hesperidin, ferulic acid, and aloin. The phenolics released during digestion were able to reduce the oxidative radicals assessed by ABTS and FRAP tests, increasing the antioxidant action in the intestine, where they are absorbed. The fermentation of Aloe vera by probiotics is an excellent process to increase the bioavailability of beverages, resulting in natural added-value functional products.