Survival and Goat Milk Acidifying Activity of Lactobacillus rhamnosus GG Encapsulated with Agave Fructans in a Buttermilk Protein Matrix

Stability of probiotics through encapsulation: Comparative analysis of current methods and solutions

Probiotics have awakened a great interest in the scientific community for their potential beneficial effects on health. Although only allowed by the European Food Safety Agency as a nutrition declaration associated with the improvement of lactose digestion, recent in vitro and in vivo studies have demonstrated their varied beneficial effect for the improvement of certain pathologies. However, probiotics face stability and viability challenges, which make their delivery difficult in sufficient quantities for these effects to be observed. Thus, there is a dire need for the development and implantation of innovative technological protection procedures. In this sense, encapsulation rises as a widely applied technique, offering additional advantages. In the present study, a systematic review was conducted for the evaluation of the main encapsulation technologies applied in literature, considering operating conditions, probiotics, and encapsulation efficacy. For this purpose, several conditions are evaluated: a) the characteristics, storage conditions and viability of probiotics; b) evaluation and comparison of the probiotic stabilization for the main encapsulation methods; and c) co-encapsulation with potential bioactive molecules as a new alternative for improving cell viability. This evaluation revealed the efficacy of seven encapsulation techniques on the improvement of the stability and viability of probiotics.

Encapsulation of Lactiplantibacillus plantarum CRD7 in sub-micron pullulan fibres by spray drying: Maximizing viability with prebiotic and thermal protectants

Pullulan was used as the wall material for microencapsulation of L. plantarum CRD7 by spray drying, while isomalto-oligosaccharides (IMO) was used as prebiotic. Also, the effect of different thermal protectants on survival rate during microencapsulation was evaluated. Taguchi orthogonal array design showed that pullulan at 14 % concentration, IMO at 30 % concentration and whey protein isolate at 20 % rate were the optimized wall material, prebiotic and thermal protectant, respectively for microencapsulation of L. plantarum. FESEM images revealed that the spray-dried encapsulates were fibrous similar to those produce by electrospinning, while fluorescence microscopy ascertained that most of the probiotic cells were alive and intact after microencapsulation. The adsorption-desorption isotherm was of Type II and the encapsulate had specific surface area of 1.92 m2/g and mean pore diameter of 15.12 nm. The typical amide II and III bands of the bacterial proteins were absent in the FTIR spectra, suggestive of adequate encapsulation. DSC thermogram showed shifting of melting peaks to wider temperature range due to interactions between the probiotic and wall materials. IMO at 30 % (w/w) along with WPI at 20 % concentration provided the highest storage stability and the lowest rate of cell death of L. plantarum after microencapsulation. Acid and bile salt tolerance results confirmed that microencapsulated L. plantarum could sustain the harsh GI conditions with >7.5 log CFU/g viability. After microencapsulation, L. plantarum also possessed the ability to ferment milk into curd with pH of 4.62.

Advances in spray-dried probiotic microcapsules for targeted delivery: a review

Probiotics have gained significant attention owing to their roles in regulating human health. Recently, spray drying has been considered as a promising technique to produce probiotic powders due to its advantages of high efficiency, cost-saving, and good powder properties. However, the severe environmental conditions from drying and digestion can significantly reduce cell viability, resulting in poor bioaccessibility and bioavailability of live cells. Therefore, there is a need to develop effective targeted delivery systems using spray drying to protect bacteria and to maintain their physiological functions in the targeted sites. This review highlights recent studies about spray-dried targeted delivery vehicles for probiotics, focusing on key strategies to protect bacteria when encountering external stresses, the formation mechanism of particles, the targeted release and colonization mechanisms of live cells in particles with different structures. Advances in the targeted delivery of live probiotics via spray-dried vehicles are still in their early stages. To increase the possibilities for industrialization and commercialization, functional improvement of microcapsules in terms of protection, targeted release, and colonization of bacteria, as well as the effect of spray drying on bacterial physiological functions in the host, need to be further investigated.

The Survival of Psychobiotics in Fermented Food and the Gastrointestinal Tract: A Review

In recent years, scientists have been particularly interested in the gut-brain axis, as well as the impact of probiotics on the nervous system. This has led to the creation of the concept of psychobiotics. The present review describes the mechanisms of action of psychobiotics, their use in food products, and their viability and survival during gastrointestinal passage. Fermented foods have a high potential of delivering probiotic strains, including psychobiotic ones. However, it is important that the micro-organisms remain viable in concentrations ranging from about 10⁶ to 10⁹ CFU/mL during processing, storage, and digestion. Reports indicate that a wide variety of dairy and plant-based products can be effective carriers for psychobiotics. Nonetheless, bacterial viability is closely related to the type of food matrix and the micro-organism strain. Studies conducted in laboratory conditions have shown promising results in terms of the therapeutic properties and viability of probiotics. Because human research in this field is still limited, it is necessary to broaden our understanding of the survival of probiotic strains in the human digestive tract, their resistance to gastric and pancreatic enzymes, and their ability to colonize the microbiota.

Development of engineered probiotics with tailored functional properties and their application in food science

The potential health benefits of probiotics may not be cognized because of the substantial curtailment in their viability during food storage and passage through the gastrointestinal system. Intestinal flora composition, and resistance against pathogens are among the health benefits associated with probiotic consumption. In the gastric environment, pH 2.0, probiotics dramatically lose their viability during the transit through the gastrointestinal system. The challenge remains to maintain cell viability until it reaches the large intestine. In extreme conditions, such as a decrease in pH or an increase in temperature, encapsulation technology can enhance the viability of probiotics. Probiotic bacterial strains can be encapsulated in a variety of ways. The methods are broadly systematized into two categories, liquid and solid delivery systems. This review emphasizes the technology used in the research and commercial sectors to encapsulate probiotic cells while keeping them alive and the food matrix used to deliver these cells to consumers.

Graphical abstract

Effect of encapsulated probiotic in Inulin-Maltodextrin-Sodium alginate matrix on the viability of Enterococcus mundtii SRBG1 and the rheological parameters of fermentedmilk

In the current research, Enterococcus mundtii SRBG1 newly isolated from Bat guano was encapsulated using spray drying technique to create a probiotic powder using six combinations of inulin, maltodextrin and sodium alginate. The encapsulation yield, moisture content, physical characteristics, and shape were investigated. Microcapsules yields ranged from 67 to 85 percent, which is consistent with typical B-290 spray-drier yields. The moisture content showed to increase (4 ± 0.15%) with the addition of sodium alginate to inulin and maltodextrin. In the gastrointestinal conditions (simulated gastric juice and bile salts), it was shown that the viability of probiotic cells in capsules was higher than that of free cells. This demonstrated the effectiveness of combining inulin and maltodextrin to encapsulate substances in surviving in gastro-intestinal conditions. Additionally, we evaluated the non-encapsulated and encapsulated SRBG1 by assessing their impact on the rheological parameters of fermented milk. The results showed that in the absence of sodium alginate the viscosity of milk was lower than with the other protectors, which was confirmed by the quick acidification of the fermented milk by microcapsules containing sodium alginate.

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Enterococcus mundtii SRBG1 isolated from Bat guano was encapsulated by spray drying.

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Six combinations of inulin, maltodextrin and sodium alginate were used.

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Microcapsules yields ranged from 67 to 85 percent.

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Inulin and maltodextrin were effective in protecting SRBG1.

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In the absence of sodium alginate the viscosity of fermented milk decreased.

The Application of Spray-Dried and Reconstituted Flaxseed Oil Cake Extract as Encapsulating Material and Carrier for Probiotic Lacticaseibacillus rhamnosus GG

Agro-industrial by-products are promising source of biopolymers, including proteins and polysaccharides. This study was designed to evaluate the flaxseed oil cake extract (FOCE) as natural encapsulating material and carrier for probiotic Lacticaseibacillus rhamnous GG (LGG). The powders were obtained using three spray drying inlet temperatures (110 °C, 140 °C, 170 °C), and reconstituted. The influence of temperature on water activity, morphology, chemical composition, flowability and cohesiveness of the powders was estimated. For all variants, the survival of bacteria during spray drying, and simulated passage through the gastrointestinal tract was evaluated. The preservation of LGG probiotic features such as cholesterol reduction, hydrophobicity and adhesion to mucin were examined. Results revealed that all physicochemical and functional characteristics of the powders were affected by the inlet temperature. This study demonstrated that FOCE is an appropriate matrix for spray drying (due to flaxseed proteins and polysaccharides) providing high survivability of bacteria (89.41-96.32%), that passed meaningfully through the simulated gastrointestinal tract (4.39-5.97 log reduction), largely maintaining their probiotic properties, being a promising environmentally-friendly carrier for probiotic LGG.

Development of pelleted feed containing probiotic Lactobacillus rhamnosus GG and Jerusalem artichoke for Nile Tilapia and its biocompatibility studies

Growth performance and immune systems of tilapias could be improved by Lactobacillus rhamnosus GG (LGG) and Jerusalem artichoke. This research aimed to determine the effects of Jerusalem artichoke on LGG viability after drying and pelleting and their subsequent exposure to simulated gastrointestinal conditions. Fresh LGG cells were added into wall material solutions, including alginate (AL), alginate + milk powder (AM), and alginate + milk powder + Jerusalem artichoke at different concentrations (AMJ). The solutions were then spray dried to obtain LGG powders. The powder with the highest cell number was then selected to mix with tilapia feed mash and pelleted using a nonthermal feed extruder to obtain pelleted feed containing LGG and Jerusalem artichoke. The LGG viability spray dried powders and pelleted feed were analyzed for their cell counts after drying and after exposure to simulated gastrointestinal conditions. The result showed that the number of viable cells in AMJ was significantly higher than AM and AL after drying. The number of viable cells under both simulated gastric and bile salt fluids was improved with the increasing of Jerusalem artichoke concentrations. The number of viable cells after pelleting process could be maintained. LGG in the pelleted feed could also survive under the simulated gastric and bile salt conditions. The study indicates that JA enhanced LGG viability after drying and exposure to simulated gastrointestinal conditions. The pelleted feed containing LGG and Jerusalem artichoke could be applied in tilapia farming, providing convenience to the farmers, and valuable effects to the fish.

Encapsulation by Electrospraying of Anticancer Compounds from Jackfruit Extract (Artocarpus heterophyllus Lam): Identification, Characterization and Antiproliferative Properties

BACKGROUND

Compounds with biological activities had been reported in the jackfruit. These compounds are susceptible to structural changes such as isomerization and/or loss of bonds due to environmental factors. Then, the encapsulation for protecting is a necessary process.

OBJECTIVE

In this study, encapsulation of High-Value Biological Compounds (HVBC) was performed using High Degree of Polymerization Agave Fructans (HDPAF) and Whey Protein (WP) as encapsulating materials to preserve the biological properties of the HVBC.

METHODS

The extract was characterized by HPLC-MS in order to show the presence of compounds with preventive or therapeutic effects on chronic degenerative diseases such as cancer. The micrographs by Scanning Electron Microscopy (SEM), Thermal Analysis (TGA and DSC), photostabilization and antiproliferation of M12.C3.F6 cell line of capsules were evaluated.

RESULTS

The micrographs of the nanocapsules obtained by Scanning Electron Microscopy (SEM) showed spherical capsules with sizes between 700 and 800nm. No cracks, dents or deformations were observed. The Thermogravimetric Analysis (TGA) evidenced the decomposition of the unencapsulated extract ranging from 154 to 221°C. On the other hand, the fructan-whey protein mixture demonstrated that nanocapsules have a thermoprotective effect because the decomposition temperature of the encapsulated extract increased 32.1°C. Differential Scanning Calorimetry (DSC) exhibited similar values of the glass transition temperature (Tg) between the capsules with and without extract; which indicates that the polymeric material does not interact with the extract compounds. The photoprotection study revealed that nanocapsules materials protect the jackfruit extract compounds from the UV radiation. Finally, the cell viability on the proliferation of M12.C3.F6 cell line was not affected by powder nanocapsules without jackfruit extract, indicating that capsules are not toxic for these cells. However, microcapsules with jackfruit extract (50μg/ml) were able to inhibit significantly the proliferation cells.

CONCLUSION

The encapsulation process provides thermoprotection and photostability, and the antiproliferative activity of HVBC from jackfruit extract was preserved.