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It is important for the probiotic to maintain its viability during food processing, gastrointestinal conditions, and storage. This study was aimed to apply the freeze-drying process to microencapsulate probiotic Lacticaseibacillus rhamnosus GG ATCC 53103. Wall materials consisted of whey protein isolate (WPI), WPI + fructooligosaccharides (WPI + FOS), WPI + galactooligosaccharides (WPI + GOS), and WPI + FOS + GOS. The results showed optimal levels of moisture content (3.85–4.1%) and water activity (0.087–0.115) in the freeze-dried powder (FDP) that contributed to the survival of L. rhamnosus during storage. The morphology of un-encapsulated FDP indicated cell deformation and pile up whereas, for encapsulated samples, they were well entrapped and randomly distributed. Freeze-dried free cells were larger than encapsulated cells, irrespective of the wall material type. The survival rate results were over 96% after freeze-drying, depending on the type of wall materials. However, in the simulated infant gastrointestinal digestion, WPI + FOS + GOS-encapsulated cells showed a minimum decline in cellular survival. The survival of encapsulated probiotics was about 11.2 and 10.22 log cfu/g before storage and at 24 weeks of storage, respectively. This decline in survivability is within an acceptable range since the encapsulated L. rhamnosus GG 53103 are for incorporation into an infant formula powder. Overall, the data demonstrated that using combination of wall materials shows a better protective effect when encapsulated L. rhamnosus GG 53,103 is freeze dried and can be used in infant formula and baby food industries. [ABSTRACT FROM AUTHOR]

Objective: Oral administration of insulin is a potential candidate for managing diabetes. However, it is obstructed by the gastrointestinal tract barriers resulting in negligible oral bioavailability. Methods: This investigation presents a novel nanocarrier platform designed to address these challenges. In this regard, the process involved amination of sodium alginate by ethylene diamine, followed by its conjugation with deoxycholic acid. Results: The resulting DCA@Alg@INS nanocarrier revealed a significantly high insulin loading content of 63.6 ± 1.03% and encapsulation efficiency of 87.6 ± 3.84%, with a particle size of 206 nm and zeta potentials of -3 mV. In vitro studies showed sustained and pH-dependent release profiles of insulin from nanoparticles. In vitro cellular studies, confocal laser scanning microscopy and flow cytometry analysis confirmed the successful attachment and internalization of DCA@Alg@INS nanoparticles in Caco-2 cells. Furthermore, the DCA@Alg@INS demonstrated a superior capacity for cellular uptake and permeability coefficient relative to the insulin solution, exhibiting sixfold and 4.94-fold enhancement, respectively. According to the uptake mechanism studies, the results indicated that DCA@Alg@INS was mostly transported through an energy-dependent active pathway since the uptake of DCA@Alg@INS by cells was significantly reduced in the presence of NaN3 by ~ 92% and at a low temperature of 4°C by ~ 94%. Conclusions: Given the significance of administering insulin through oral route, deoxycholic acid-modified alginate nanoparticles present a viable option to surmount various obstacles presented by the gastrointestinal. [ABSTRACT FROM AUTHOR]

The purpose of this work was to study the ability of nineteen food-grade microorganisms as Pickering emulsion (PE) stabilizers. Medium-chain triacylglycerol (MCT) oil-in-water (50:50) PEs were fabricated by 10 wt% or 15 wt% of thermally-inactivated yeast, cocci, Bacillus spp. and lactobacilli cells. The characteristics of microorganisms related to "Pickering stabilization" including morphology, surface charge, interfacial tension, and "contact angle" were firstly studied. After that, the cells-stabilized PEs were characterized from both kinetic and thermodynamic viewpoints, microstructure and rheological properties. The interfacial tension and "contact angle" values of various microorganisms ranged from 16.33 to 38.31 mN/m, and from 15° to 106°, respectively. The mean droplet size of PEs ranged from 11.51 to 57.69 µm. Generally, the physical stability of cell-stabilized PEs followed this order: lactobacilli > Bacillus spp. > cocci > yeast. These variations were attributed to the morphology and cell wall composition. Increasing the microorganism concentration significantly increased the physical stability of PEs from a maximum of 12 days at 10 wt% to 35 days at 15 wt% as a result of better interface coverage. Shear-thinning and dominant elastic behaviors were observed in PEs. Physical stability was affected by the free energy of detachment. Therefore, food-grade microorganisms are suggested for stabilizing PEs. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the electrostatic interaction between soy protein isolate (SPI) and water-soluble part of Persian gum (PG) as function of pH (2–7), protein to polysaccharide mixing ratio (MR 8:1–1:10), and total concentration of biopolymer (TC 0.1, 0.3 and 0.6% W/W). The results showed that the formation of soluble complexes was initiated near the isoelectric point (pI) of SPI. Decreasing the MR reduced the values of two critical pH (pHφ and pHopt) with a more considerable effect at TC of 0.1% W/W for pHopt. The effect of ionic strength was also studied using two salts (NaCl and CaCl2) at different concentrations (0–200 mM). Increasing ionic strength prevented the interaction due to the charge screening effect. Particle size and zeta potential of physically stable complexes ranged from 466 to 701 nm and − 70 to − 82 mV, respectively. The relative viscosity of SPI/WPG mixture was decreased from 2.20 to 1.24 during pH reduction from 6.0 to 3.8 confirming the compaction phenomenon. The stable colloidal systems might have applications in designing delivery systems for utilization in food products and beverages. [ABSTRACT FROM AUTHOR]

After its emergence in late 2019 SARS-CoV-2 was declared a pandemic by the World Health Organization on 11 March 2020 and has claimed more than 2.8 million lives. There has been a massive global effort to develop vaccines against SARS-CoV-2 and the rapid and low cost production of large quantities of vaccine is urgently needed to ensure adequate supply to both developed and developing countries. Virus-like particles (VLPs) are composed of viral antigens that self-assemble into structures that mimic the structure of native viruses but lack the viral genome. Thus they are not only a safer alternative to attenuated or inactivated vaccines but are also able to induce potent cellular and humoral immune responses and can be manufactured recombinantly in expression systems that do not require viral replication. VLPs have successfully been produced in bacteria, yeast, insect and mammalian cell cultures, each production platform with its own advantages and limitations. Plants offer a number of advantages in one production platform, including proper eukaryotic protein modification and assembly, increased safety, low cost, high scalability as well as rapid production speed, a critical factor needed to control outbreaks of potential pandemics. Plant-based VLP-based viral vaccines currently in clinical trials include, amongst others, Hepatitis B virus, Influenza virus and SARS-CoV-2 vaccines. Here we discuss the importance of plants as a next generation expression system for the fast, scalable and low cost production of VLP-based vaccines. [ABSTRACT FROM AUTHOR]

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) together with CRISPR-associated (Cas) proteins have catalysed a revolution in genetic engineering. Native CRISPR-Cas systems exist in many bacteria and archaea where they provide an adaptive immune response through sequence-specific degradation of an invading pathogen's genome. This system has been reconfigured for use in genome editing, drug development, gene expression regulation, diagnostics, the prevention and treatment of cancers, and the treatment of genetic and infectious diseases. In recent years, CRISPR-Cas systems have been used in the diagnosis and control of viral diseases, for example, CRISPR-Cas12/13 coupled with new amplification techniques to improve the specificity of sequence-specific fluorescent probe detection. Importantly, CRISPR applications are both sensitive and specific and usually only require commonly available lab equipment. Unlike the canonical Cas9 which is guided to double-stranded DNA sites of interest, Cas13 systems target RNA sequences and thus can be employed in strategies directed against RNA viruses or for transcriptional silencing. Many challenges remain for these approach, including issues with specificity and the requirement for better mammalian delivery systems. In this review, we summarize the applications of CRISPR-Cas systems in controlling mammalian viral infections. Following necessary improvements, it is expected that CRISPR-Cas systems will be used effectively for such applications in the future. [ABSTRACT FROM AUTHOR]

Monoclonal antibodies (mAbs) are widely employed as invaluable therapeutics for a vast number of human disorders. Several approaches have been introduced for the improvement of mAb production in Chinese hamster ovary (CHO) cells due to the increasing demand for these products. In this regard, various chromatin-modifying elements such as insulators have been incorporated in the expression vectors to augment mAb expression. In this study, human gamma-satellite insulator containing vectors were utilized for the expression of an anti-proprotein convertase subtilisin/kexin type 9 (PCSK9) mAb in CHO-K1 cells. To this aim, dual expression vectors encoding the antibody light chain (LC) and heavy chain (HC) with or without the insulator element were constructed, and mAb expression was evaluated in transient and stable expression. Based on the results, mAb expression significantly increased in the stable cell pool, and clonal cells developed using the human gamma-satellite insulator. In contrast, transient antibody expression was not affected by the insulator element. Finally, the enhancement of LC and HC mRNA levels was found in the insulator containing stable cell pools using the quantitative real-time-polymerase chain reaction (qRT-PCR). Our findings showed the positive effect of the human gamma-satellite insulator on the stable expression of an anti-PCSK9 immunoglobulin G1 (IgG1) mAb in CHO-K1 cells using dual expression vectors. [ABSTRACT FROM AUTHOR]

Many flavoring agents on the market are extracted from natural sources or synthesized chemically. Due to the disadvantages of both methods, biotechnology is becoming a promising alternative. In this study, short chain ethyl esters with fruity notes were biosynthesized in UHT whole milk via coupling ethanolic fermentation with lipase (Palatase®) transesterification. Kluyveromyces marxianus, Lactobacillus fermentum and Lb. paracasei were used for fermentation. Milk fat was esterified with in situ produced ethanol by adding lipase at 0, 8 and 24 h of fermentation. Viable cell counts and pH were monitored during 48 h fermentation period. Flavor active ethyl esters, ethanol and free fatty acids were analyzed using headspace SPME-GC. Free fatty acid levels were lower in K. marxianus samples than lactobacilli. K. marxianus produced higher amounts of ethanol and esters than lactic acid bacteria. Viable cell counts decreased after lipase application at 0 and 8 h, possibly due to fatty acid production. Addition of lipase at 24 h resulted in improved cell counts as well as ethanol and ester production in the case of K. marxianus. This study demonstrated that fermenting milk with alcohol producing cultures in conjunction with lipase application can be an alternative to artificial flavorings in fermented milks. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of Lactobacillus plantarum and Bacillus coagulans on serum lipid profile and lowering potential of probiotic in hypercholesterolemic rats. Twenty-eight male Wistar rats were divided into four groups as follows: (1) control group, fed standard commercial diet; (2) HC group, fed high-cholesterol diet; (3) HC + LP group, fed high-cholesterol diet and gavaging of L. plantarum; and (4) HC + BC group fed high-cholesterol diet and gavaging of B. coagulans. After 28 and 50 days, serum lipid profile; serum ALT and AST; the body and organ weights; fecal total count; Enterobacteriaceae, L. plantarum, and B. coagulans counts; and blood glucose tolerance were measured. We observed that levels of triglyceride, cholesterol, LDL, VLDL, and atherogenic index in serum were significantly lower in the HC + probiotic groups. Also, serum ALT and AST were significantly decreased in probiotic-treated groups. In addition, we found that feeding of a high-cholesterol diet for 50 days produced significant increases in the body weight, in addition to the fact that the administration of L. plantarum and B. coagulans has considerably reduced the body weight gain. B. coagulans and L. plantarum can survive passing through the upper-gastrointestinal tract after oral feeding to the rats and colonized in their colon. These bacteria could be exploited as a potential biotherapeutic remedy to reduce TC, TG, LDL, VLDL, and atherogenic index in hypercholesterolemic condition. [ABSTRACT FROM AUTHOR]

Kefir is a natural probiotic compound with a long history of health benefits which can improve wound healing. This study investigated the regeneration potential of kefir in vitro scratch assay and in vivo burn wound in rat model. Cytotoxicity of different concentrations of kefir was evaluated by colorimetric methylthiazoltetrazolium assay. A scratch wound experiment was performed to investigate the ability of kefir in reducing the gap of wounds in a dose-dependent manner, in vitro. The standardized kefir was incorporated into silver sulfadiazine (SSD) and applied on burn wounds in vivo, and was compared with the SSD and negative control groups after 7, 14, and 28 days of treatment. The wound sites were then removed for histopathological and morphometric analyses, assessment of interleukin-1β (IL-1β), transforming growth factor-β1 (TGF-β1), basic fibroblast growth factor (bFGF), dry weight, and hydroxyproline contents. Kefir enhanced proliferation and migration of human dermal fibroblast (HDF) cells and 12.50, 6.25, and 3.12 μL/mL concentrations showed better effects on the scratch assay. Kefir resulted in reduction of IL-1β and TGF-β1 expression at day 7 compared to the negative control. Kefir also reduced the expression of IL-1β at days 14 and 28 and stimulated bFGF at day 28. It significantly improved the dry matter and hydroxyproline contents in the burn wounds. Kefir also resulted in enhanced angiogenesis and elevated migration and proliferation of fibroblasts and improved fibrous connective tissue formation in the wound area. The morphometric results indicated significant global contraction values in the kefir-treated wounds compared to other groups. Taken together, the findings suggest that kefir has considerable ability to accelerate healing of the burn wounds. Therefore, kefir may be a possible option to improve the outcomes of severe burns. [ABSTRACT FROM AUTHOR]

Effects of Spirulina (Arthrospira platensis) addition were evaluated on probiotic Lactobacillus casei growth in bacteriologically acidified feta-type (BAF) cheese. The chemical, textural, and sensorial characteristics of cheese were measured. After 60 days of storage, there were significantly higher viable counts of Lb. casei (9.10–9.35 log CFU g−1) in Spirulina samples in comparison with the control (8.68 log CFU g−1). The viable counts of Lb. casei were maintained more successfully in the probiotic BAF cheese which contained Spirulina. The values of titratable acidity, dry matter, and protein contents of Spirulina samples were higher than the control. Furthermore, samples with Spirulina exhibited softer textures which led to an easier disintegration and chewing of the BAF cheese. Based on the results of the sensorial evaluation, no significant difference was observed between the control and the samples with 0.5 or 1.0% Spirulina. In conclusion, Spirulina is deemed a satisfactory nutritional source which can be added to BAF cheese without having any adverse effects on its characteristics. Graphical abstract Effect of Spirulina powder on probiotic BAF cheese [ABSTRACT FROM AUTHOR]

This study was aimed to evaluate the antibacterial and antioxidant characteristics of incorporated pomegranate juice (PJ) and pomegranate rind powder extract (PRPE) into meat burgers. The peroxide value, thiobarbituric acid reactive substances, and metmyoglobin content for different burgers during 90 days storage at − 18 °C were evaluated. Total anthocyanin content, total phenolic content (TPC) and free radical scavenging activity (RSA or IC50) for PJ and PRPE were measured as 18.90 (mg/mL), 4380 ppm, 0.136 (mg/mL) and 0.40 (mg/mL), 5598 ppm, 0.084(mg/mL), respectively. Incorporation of PRPE with a high concentration of TPC resulted in less oxidation of lipid in comparison with other formulations. The highest and lowest scores in the sensory analysis and total acceptance at the 90th day corresponded to burgers containing PJ and control, respectively. Butylated hydroxytoluene may be substituted in whole or part with PJ and PRPE due to their desired effects on burgers' properties. [ABSTRACT FROM AUTHOR]

In this study, application of various concentrations (0.025%, 0.05% and 0.075%) of Carum copticum essential oil (EO) were examined on oxidative stability of sunflower oil and there were compared to Butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) during storage at 37 and 47 °C. The main compounds of EO were identified as thymol (50.07%), γ- terpinene (23.92%) and p-cymene (22.9%). Peroxide value (PV), anisidine value (AnV) and thiobarbituric acid (TBA) value measurement in sunflower oil showed that all concentrations of EO had antioxidant effect in comparison to BHA and BHT. Samples added with EO at 0.075% were the most stable during storage at both temperatures ( P < 0.05). Furthermore, Totox value, antioxidant activity (AA), stabilization factor (F) and antioxidant power (AOP) determination confirmed efficacy of this EO as antioxidant in sunflower oil. EO also was able to reduce the stable free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) with a 50% inhibition concentration (IC 50) of 20.3 ± 0.9 μg/mL. Therefore, the results indicate that EO could be used as a natural antioxidant in food lipids. [ABSTRACT FROM AUTHOR]