Controlled release and enhanced biological activity of chitosan-fabricated carbenoxolone nanoparticles

Effects of a chitosan nanoparticles encapsulation on the properties of litchi polyphenols

Litchi polyphenols have very specific biological activities. Nevertheless, the low and inconsistent oral bioavailability and instability hinder the further application of litchi polyphenols in food systems. This work prepared litchi polyphenols loaded chitosan nanoparticles (LP-CSNPs) by ionic gelation method to enhance the encapsulation on the properties of litchi polyphenols. The optimum conditions of formation via single factors and the Box-Behnken design were chitosan (CS) concentration 1.065 mg/mL, sodium tripolyphosphate (TPP) concentration 0.975 mg/mL, and the mass ratios of polyphenols and CS 1:1 with encapsulation efficiency (EE%) of 45.53%. LP-CSNPs presented the nanosized range of particle size (mean 170 nm), excellent polydispersity index (PDI) (0.156 ± 0.025), and zeta potential values (+ 35.44 ± 0.59). The in vitro release in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 6.8) during 100 h was 58.34% and 81.68%, respectively. LP-CSNPs could effectively improve the storage stability and had great antibacterial activity compared with unencapsulated litchi polyphenols.

Optimisation of liquorice extract microencapsulation and bioaccessibility of its bioactives

In this work, functional liquorice powder beverage (FLPB) with standardised glycyrrhizin (GL), glycyrrhetinic acid (GA), carbenoxolone (CBX), and liquiritin (LQ) contents, was produced by encapsulating Glycyrrhiza glabra extract with maltodextrin (MD) by spray drying. Encapsulation parameters of the FLPB were optimised as MD:GL 3.4:1, inlet temperature: 149 °C, and air flow: 8.9 L min−1. GL, GA, LQ, CBX, and yield in powdered beverage produced using these optimised parameters were 6.8 g L−1, 81.1 mg L−1, 24.7 mg L−1, 0.79 g L−1, and 30.95%, respectively. Moreover, the effect of the encapsulation on the bioaccessibility of GL, GA, CBX, and LQ bioactives in G. glabra was evaluated. According to the obtained results, FLPB exhibited a higher bioaccessibility index for GL, GA, CBX, and LQ compared to the aqueous extract.

Preparation of Betulinic Acid Galactosylated Chitosan Nanoparticles and Their Effect on Liver Fibrosis

Aim

Liver fibrosis is mainly characterized by the formation of fibrous scars. Galactosylated chitosan (GC) has gained increasing attention as a liver-targeted drug carrier in recent years. The present study aimed to investigate the availability of betulinic acid-loaded GC nanoparticles (BA-GC-NPs) for liver protection. Covalently-conjugated galactose, recognized by asialoglycoprotein receptors exclusively expressed in hepatocytes, was employed to target the liver.

Materials and Methods

Galactose was coupled to chitosan by chemical covalent binding. BA-GC-NPs were synthesized by wrapping BA into NPs via ion-crosslinking method. The potential advantage of BA-GC-NP as a liver-targeting agent in the treatment of liver fibrosis has been demonstrated in vivo and in vitro.

Results

BA-GC-NPs with diameters <200 nm were manufactured in a virtually spherical core-shell arrangement, and BA was released consistently and continuously for 96 h, as assessed by an in vitro release assay. According to the safety evaluation, BA-GC-NPs demonstrated good biocompatibility at the cellular level and did not generate any inflammatory reaction in mice. Importantly, BA-GC-NPs showed an inherent liver-targeting potential in the uptake behavioral studies in cells and bioimaging tests in vivo. Efficacy tests revealed that administering BA-GC-NPs in a mouse model of liver fibrosis reduced the degree of liver injury in mice.

Conclusion

The findings showed that BA-GC-NPs form a safe and effective anti-hepatic fibrosis medication delivery strategy.

An Insight into Efflux-Mediated Arsenic Resistance and Biotransformation Potential of Enterobacter Cloacae RSC3 from Arsenic Polluted Area

Indiscriminate discharge of heavy metals/metalloids from different sources into the sustainable agro-ecosystem is a major global concern for food security and human health. Arsenic (As), categorized as group one human carcinogen is a quintessential toxic metalloid that alters the microbial compositions and functions, induce physiological and metabolic changes in plants and contaminate surface/ground water. The management of arsenic toxicity, therefore, becomes imminent. Acknowledging the arsenic threat, the study was aimed at identifying arsenic resistant bacteria and evaluating its arsenic removal/detoxification potential. Of the total 118 bacterial isolates recovered from arsenic rich environment, the bacterial strain RSC3 demonstrating highest As tolerance was identified as Enterobacter cloacae by 16S rRNA gene sequence analysis. Enterobacter cloacae tolerated high concentration (6000 ppm) of As and exhibited 0.55 h-1 of specific growth rate as calculated from growth kinetics data. Strain RSC3 also displayed varying level of resistance to other heavy metals and many antibacterial drugs in plate bioassay. The bacterial strain RSC3 possessed gene (arsC) which causes transformation of arsenate to arsenite. The arsenate uptake and efflux of the bacterial cells was revealed by high throughput techniques such as AAS, SEM/TEM and EDX. The simultaneous As reducing ability, and multi metal/multi-antibiotics resistance potentials of E. cloacae provides a promising option in the microbes based remediation of As contaminated environments.

Development of Inhalable Nanostructured Lipid Carriers for Ciprofloxacin for Noncystic Fibrosis Bronchiectasis Treatment

Purpose

Ciprofloxacin (CIP) has poor lung targeting after oral inhalation. This study developed optimized inhalable nanostructured lipid carriers (NLCs) for CIP to enhance deposition and accumulation in deeper parts of the lungs for treatment of noncystic fibrosis bronchiectasis (NCFB).

Methods

NLC formulations based on stearic acid and oleic acid were successfully prepared by hot homogenization and in vitro-characterized. CIP-NLCs were formulated into nanocomposite micro particles (NCMPs) for administration in dry powder inhalation (DPI) formulations by spray-drying (SD) using different ratios of chitosan (CH) as a carrier. DPI formulations were evaluated for drug content and in vitro deposition, and their mass median aerodynamic diameter (MMAD), fine particle fraction (FPF), fine particle dose (FPD), and emitted dose (ED) were determined.

Results

The CIP-NLCs were in the nanometric size range (102.3 ± 4.6 nm), had a low polydispersity index (0.267 ± 0.12), and efficient CIP encapsulation (98.75% ± 0.048%), in addition to a spherical and smooth shape with superior antibacterial activity. The in vitro drug release profile of CIP from CIP-NLCs showed 80% release in 10 h. SD of CIP-NLCs with different ratios of CH generated NCMPs with good yield (>65%). The NCMPs had a corrugated surface, but with increasing lipid:CH ratios, more spherical, smooth, and homogenous NCMPs were obtained. In addition, there was a significant change in the FPF with increasing lipid:CH ratios (P ˂ 0.05). NCMP-1 (lipid:CH = 1:0.5) had the highest FPD (45.0 µg) and FPF (49.2%), while NCMP-3 (lipid:CH = 1:1.5) had the lowest FPF (37.4%). All NCMP powders had an MMAD in the optimum size range of 3.9–5.1 μm.

Conclusion

Novel inhalable CIP NCMP powders are a potential new approach to improved target ability and delivery of CIP for NCFB treatment.

In silico and experimental studies of bovine serum albumin-encapsulated carbenoxolone nanoparticles with reduced cytotoxicity

Carbenoxolone (CBX) is a semi-synthetic plant derivative with pleiotropic pharmacological properties like anti-microbial and anti-inflammatory activities. Though approved for treatment of gastric ulcers, its use is limited due to adverse effects such as cytotoxicity. Bovine serum albumin (BSA) is a natural, non-toxic protein with high water-solubility and low immunogenicity, and is widely used as a nanocarrier for targeted drug delivery. In the present study, controlled release BSA-CBX nanoparticles (NPs) were synthesized by desolvation method to reduce drug cytotoxicity. These NPs showed desirable physicochemical properties such as particle size (∼240 nm), polydispersity index (0.08), zeta potential (-7.12 mV), drug encapsulation efficiency (72 %), and were stable for at least 3 months at room temperature. The drug was released from the BSA-CBX NPs in a biphasic manner in vitro following non-fickian diffusion. Computational analysis determined that the binding between BSA and CBX occurred through van der Waals forces, hydrophobic interactions, and hydrogen bonds with 93 % steric stability. Further, the cytotoxic assays demonstrated ∼1.8-4.9-fold reduction in cytotoxicity using three human cell lines (A549, MCF-7, and U-87). Subsequently, this novel CBX formulation with BSA as an efficient carrier can potentially be used for diverse biomedical applications.