scholarly journals Hydrogels Made of Poly-γ-Glutamic Acid and Sugar Alcohols for Enhanced Survival of Probiotic Strains Subjected to Low pH and Freeze Drying

AppliedChem ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 173-183
Author(s):  
Iwona Kwiecień ◽  
Anabel Itohowo Ekere ◽  
Monika Śmiga-Matuszowicz

Probiotics are microorganisms that have a beneficial influence on the human gastrointestinal tract. Unfortunately, their viability can be negatively affected by manufacturing, storage conditions and gastrointestinal tract conditions. Therefore, there is a need to develop delivery systems, which can protect probiotics against adverse conditions. Previously, we reported on hydrogels made of poly-γ-glutamic acid (γ-PGA) and selected PEGs with the potential application as probiotic delivery vehicles. In the next step of research, we decided to develop fully biobased hydrogels with the potential application as probiotic oral-delivery systems. Selected sugar alcohols, erythritol, xylitol and sorbitol, have been used as cross-linkers in the synthesis of γ-PGA-based hydrogels. It was examined if obtained hydrogels enhanced the survival rate of entrapped probiotic strains subjected to acidic conditions. Results have been discussed in relation to the previously reported γ-PGA-PEG hydrogels. Moreover, the possibility of using developed hydrogels as a cryoprotectant was investigated during freeze drying of entrapped probiotic cells.

Pharmaceutics ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 1052
Author(s):  
Reem Abou Assi ◽  
Ibrahim M. Abdulbaqi ◽  
Toh Seok Ming ◽  
Chan Siok Yee ◽  
Habibah A. Wahab ◽  
...  

Azithromycin (AZM) is a macrolide antibiotic used for the treatment of various bacterial infections. The drug is known to have low oral bioavailability (37%) which may be attributed to its relatively high molecular weight, low solubility, dissolution rate, and incomplete intestinal absorption. To overcome these drawbacks, liquid (L) and solid (S) self-emulsifying drug delivery systems (SEDDs) of AZM were developed and optimized. Eight different pseudo-ternary diagrams were constructed based on the drug solubility and the emulsification studies in various SEDDs excipients at different surfactant to co-surfactant (Smix) ratios. Droplet size (DS) < 150 nm, dispersity (Đ) ≤ 0.7, and transmittance (T)% > 85 in three diluents of distilled water (DW), 0.1 mM HCl, and simulated intestinal fluids (SIF) were considered as the selection criteria. The final formulations of L-SEDDs (L-F1(H)), and S-SEDDs (S-F1(H)) were able to meet the selection requirements. Both formulations were proven to be cytocompatible and able to open up the cellular epithelial tight junctions (TJ). The drug dissolution studies showed that after 5 min > 90% and 52.22% of the AZM was released from liquid and solid SEDDs formulations in DW, respectively, compared to 11.27% of the pure AZM, suggesting the developed SEDDs may enhance the oral delivery of the drug. The formulations were stable at refrigerator storage conditions.


2018 ◽  
Vol 2018 ◽  
pp. 1-22 ◽  
Author(s):  
Mayra Alejandra Mendez-Encinas ◽  
Elizabeth Carvajal-Millan ◽  
Agustín Rascon-Chu ◽  
Humberto Francisco Astiazaran-Garcia ◽  
Dora Edith Valencia-Rivera

In the last years, biomedical research has focused its efforts in the development of new oral delivery systems for the treatment of different diseases. Ferulated arabinoxylans are polysaccharides from cereals that have been gaining attention in the pharmaceutical field due to their prebiotic, antioxidant, and anticancer properties. The antioxidant and anticancer properties of these polysaccharides make them attractive compounds for the treatment of cancer, particularly colon cancer. In addition, ferulated arabinoxylans can form covalent gels through the cross-linking of their ferulic acids. Due to their particular characteristics, ferulated arabinoxylan gels represent an excellent alternative as colon-targeted drug delivery systems. The aim of the present work is to review the physicochemical and functional properties of ferulated arabinoxylans and their gels and to present the future perspectives for potential application as antioxidant and anticancer agents.


Author(s):  
Malireddy S Reddy

The worldwide popularity of Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy to treat or prevent the hospital acquired infections (nosocomial infections) arose a great interest in the medical community around the world (Reddy and Reddy, 2016; 2017). The following questions were raised on this subject: Does Multiple Mixed Strain Probiotics directly inhibit the pathogenic bacteria (C. diff) in the gastrointestinal tract or indirectly through modulation of the host immune system or both? To be more specific, what is the exact and/or hypothetical mechanism at molecular level behind the breakthrough discovery of Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy?  To answer these questions, the specific immunomodulation regulatory functions of the individual Probiotic strains (on host) have beenresearched, investigated andoutlined in this article.  A detailed explanation(s) and hypotheses have been proposed outlining the possible cumulativedirect bacteriological and indirect immunomodulatory effects (at the molecular level) of the Multiple Mixed Strain Probiotics used in Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy to successfully treat C. diff infection.  A detailed scientific and research attempts were made to correlate the Probiotic induced immune activities in relation to the reduction of the symptoms associated with the hospital acquired Clostridium difficile infection during and after the Multiple Mixed Strain Probioitc Therapy.  Results of the clinical trials, microbiological tests on feces, and the clinical blood tests significantly revealed that the reasons for the success of Dr. Reddy’s Multiple Mixed Strain Probiotic Therapy are multifold. Presumably, it is predominantly due to the immunomodulatory effect they have exerted on the host immune system along with the direct inhibition of C. diff bacteria by multiple Probiotics, due to the production of bacteriocins, lactic acid and nutritional competency.In addition, the size of the individual cells of the Probiotic strains in the Multiple Mixed Strain Probiotics and their significant effect on immunomodulation has been thoroughly discussed. Results clearly proved that if Probiotics are absent in the GI tract during C. diff infection, the chances of patient survival is zero.  This is because of the excess immune stimulation and incurable damage to the epithelial cell barrier of the gastrointestinal tract caused by C. diff bacteria.  The results also revealed, without any doubt, as of to-datethe latest discovery of Dr. M.S. Reddy’s Multiple Mixed Strain Probiotic Therapy is the best way to cure the deadly hospital acquired infections affecting millions of people around the world, with high degree of mortality.  This has been attested by several practicng medical professionals and scientists around the world (Reddy and Reddy, 2017).


2020 ◽  
Vol 17 (3) ◽  
pp. 229-245
Author(s):  
Gang Wang ◽  
Junjie Wang ◽  
Rui Guan

Background: Owing to the rich anticancer properties of flavonoids, there is a need for their incorporation into drug delivery vehicles like nanomicelles for safe delivery of the drug into the brain tumor microenvironment. Objective: This study, therefore, aimed to prepare the phospholipid-based Labrasol/Pluronic F68 modified nano micelles loaded with flavonoids (Nano-flavonoids) for the delivery of the drug to the target brain tumor. Methods: Myricetin, quercetin and fisetin were selected as the initial drugs to evaluate the biodistribution and acute toxicity of the drug delivery vehicles in rats with implanted C6 glioma tumors after oral administration, while the uptake, retention, release in human intestinal Caco-2 cells and the effect on the brain endothelial barrier were investigated in Human Brain Microvascular Endothelial Cells (HBMECs). Results: The results demonstrated that nano-flavonoids loaded with myricetin showed more evenly distributed targeting tissues and enhanced anti-tumor efficiency in vivo without significant cytotoxicity to Caco-2 cells and alteration in the Trans Epithelial Electric Resistance (TEER). There was no pathological evidence of renal, hepatic or other organs dysfunction after the administration of nanoflavonoids, which showed no significant influence on cytotoxicity to Caco-2 cells. Conclusion: In conclusion, Labrasol/F68-NMs loaded with MYR and quercetin could enhance antiglioma effect in vitro and in vivo, which may be better tools for medical therapy, while the pharmacokinetics and pharmacodynamics of nano-flavonoids may ensure optimal therapeutic benefits.


Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 781
Author(s):  
Sadaf Jamal Gilani ◽  
May Nasser Bin-Jumah ◽  
Syed Sarim Imam ◽  
Sultan Alshehri ◽  
Mohammed Asadullah Jahangir ◽  
...  

The authors wish to make the following corrections to this paper [...]


2020 ◽  
Vol 41 (2) ◽  
pp. 105
Author(s):  
Javier Fernando Melo-Bolívar ◽  
Ruth Yolanda Ruiz-Pardo ◽  
Michael E Hume ◽  
Hanna E Sidjabat ◽  
Luisa Marcela Villamil-Diaz

Probiotic products are viewed as an alternative to the use of antibiotics in freshwater fishes farming. Probiotic organisms include bacteria, yeast, and filamentous fungi offering different benefits to fish including growth promotion, inhibition of pathogen colonisation, and improvement of nutrient digestion, water quality, and stress tolerance, as well as enhancement of reproduction. For these reasons, this review aims to identify the main trends in probiotic amendment in freshwater fishes. Strategies to incorporate the probiotic strains in the fish feed or pellets to allow optimal viability of the strains as they reach the fish gastrointestinal tract (GIT) are crucial in probiotic research and commercial applications for freshwater fish.


2019 ◽  
Vol 87 (3) ◽  
pp. 20 ◽  
Author(s):  
Miléna Lengyel ◽  
Nikolett Kállai-Szabó ◽  
Vince Antal ◽  
András József Laki ◽  
István Antal

Microparticles, microspheres, and microcapsules are widely used constituents of multiparticulate drug delivery systems, offering both therapeutic and technological advantages. Microparticles are generally in the 1–1000 µm size range, serve as multiunit drug delivery systems with well-defined physiological and pharmacokinetic benefits in order to improve the effectiveness, tolerability, and patient compliance. This paper reviews their evolution, significance, and formulation factors (excipients and procedures), as well as their most important practical applications (inhaled insulin, liposomal preparations). The article presents the most important structures of microparticles (microspheres, microcapsules, coated pellets, etc.), interpreted with microscopic images too. The most significant production processes (spray drying, extrusion, coacervation, freeze-drying, microfluidics), the drug release mechanisms, and the commonly used excipients, the characterization, and the novel drug delivery systems (microbubbles, microsponges), as well as the preparations used in therapy are discussed in detail.


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