Dry heat stress stability evaluation of casein peptide mixture

Hot-Melt Preparation of a Non-Biodegradable Peptide Implant: A Proof of Principle

BACKGROUND

Both biodegradable and non-biodegradable peptide-loaded implants are already developed for the long-term treatment of patients, thereby reducing the frequency of drug administration. To further improve peptide formulation, extending the scope of implant-based drug delivery systems towards other polymers and processing techniques is highly interesting.

OBJECTIVE

In this study, as a proof-of-principle, the feasibility of hot-melt processing of a peptide active pharmaceutical ingredient was assessed by developing a non-biodegradable poly(ethylenevinyl acetate) (33% VA) implant loaded with 20% (w/w) buserelin acetate.

METHODS

Cross-sectional implant characterization was performed by Raman microscopy. The stability of buserelin acetate in the polymeric matrix was evaluated for 3 months under ICH stability conditions and the quantity as well as the degradation products analyzed using LC-UV methods. An in vitro dissolution study was performed as well and buserelin acetate and its degradants analyzed using the same chromatographic methods.

RESULTS

No significant quantities of buserelin acetate-related degradation products were formed during the hot-melt preparation as well as during the stability study. Together with the consistent buserelin acetate assay values over time, chemical peptide stability was thus demonstrated. The in vitro buserelin acetate release from the implant was found to be diffusion-controlled after an initial burst release, with stable release profiles in the stability study, demonstrating the functional stability of the peptide implant.

CONCLUSION

These results indicate the feasibility of preparing non-biodegradable peptide-loaded implants using the hot-melt production method and may act as a proof of principle concept for further innovation in peptide medicinal formulations.

Bioactivity of a Rice Bran-Derived Peptide and its Sensory Evaluation and Storage Stability in Orange Juice

A pentapeptide prepared from rice bran demonstrated growth inhibition on human lung, liver, breast, and colon cancer cell lines. The objectives of this study were to evaluate the human prostate cancer growth inhibition by the pentapeptide and its 6-mo storage stability by incorporating spray-dried orange juice, and determining sensory acceptability. The pentapeptide showed inhibition of human prostate cancer cells by 45% at 460 μg/mL concentration. When incorporated in spray-dried orange juice, and reconstituted with water and tested, there was an approximately 10% degradation of the peptide at 620 μg/mL concentration under refrigerated conditions over a 6 mo storage period, whereas at ambient temperature the degradation was 30%. Larger degradation was observed when 240 or 460 μg/mL pentapeptide was used. Overall, consumer panelists liked sensory aspect of the reconstituted pentapeptide incorporated orange juice beverage. Also consumer panelists liked the color and mouthfeel attributes, their hedonic impression of flavor attribute was slightly low due to unpalatable bitter note caused by the presence of the peptide. Incorporation of the pentapeptide in spray-dried orange juice has the potential to serve as a functional food ingredient that can offer health benefits to consumers. It is possible that the structural instability can be minimized by encapsulation.

Effect of oven drying and freeze drying on the antioxidant and functional properties of protein hydrolysates derived from freshwater fish (Cirrhinus mrigala) using papain enzyme

Fish protein hydrolysate (FPH) was prepared from fresh water fish Cirrhinus mrigala using papain and dried in oven (OD-FPH) and freeze dryer (FD-FPH). The electron micrographs of FD-FPH samples showed porous structure. The browning intensity of OD-FPH samples was higher than the FD-FPH samples. The DPPH (2, 2 Diphenyl-1-picrylhydrazyl) free radical scavenging activity and linoleic acid peroxidation inhibition activity of FPH were not affected by oven drying process. The sequential digestion of FPH with pepsin and pancreatin reduced the antioxidant properties in both OD-FPH and FD-FPH samples. The solubility of proteins in OD-FPH was lower at pH 5 while for that of FD-FPH it was at pH 7 with water as solvent. The surface active properties of FD-FPH samples were higher than OD-FPH samples. The oven drying of fish protein hydrolysates may be advocated considering the properties and cost of production.

Influence of Different Drying Treatments and Extraction Solvents on the Metabolite Profile and Nitric Oxide Inhibitory Activity of Ajwa Dates

This study aimed to examine the variation in the metabolite profiles and nitric oxide (NO) inhibitory activity of Ajwa dates that were subjected to 2 drying treatments and different extraction solvents. (1)H NMR coupled with multivariate data analysis was employed. A Griess assay was used to determine the inhibition of the production of NO in RAW 264.7 cells treated with LPS and interferon-γ. The oven dried (OD) samples demonstrated the absence of asparagine and ascorbic acid as compared to the freeze dried (FD) dates. The principal component analysis showed distinct clusters between the OD and FD dates by the second principal component. In respect of extraction solvents, chloroform extracts can be distinguished by the absence of arginine, glycine and asparagine compared to the methanol and 50% methanol extracts. The chloroform extracts can be clearly distinguished from the methanol and 50% methanol extracts by first principal component. Meanwhile, the loading score plot of partial least squares analysis suggested that beta glucose, alpha glucose, choline, ascorbic acid and glycine were among the metabolites that were contributing to higher biological activity displayed by FD and methanol extracts of Ajwa. The results highlight an alternative method of metabolomics approach for determination of the metabolites that contribute to NO inhibitory activity.

PRACTICAL APPLICATION

The association between metabolite profiles and nitric oxide (NO) inhibitory activity of the various extracts of Ajwa dates was evaluated by utilizing partial least squares (PLS) model. The validated PLS model can be employed to predict the NO inhibitory activity of new samples of date fruits based on their NMR spectra which was important for assessing fruit quality. The information gained might be used as guidance for quality control, nutritional values and as a basis for the preparation of any food supplements for human health that employs date palm fruit as the raw material.

Reversed-phase fused-core HPLC modeling of peptides

Different fused-core stationary phase chemistries (C18, Amide, Phenyl-hexyl and Peptide ES-C18) were used for the analysis of 21 structurally representative model peptides. In addition, the effects of the mobile phase composition (ACN or MeOH as organic modifier; formic acid or acetic acid, as acidifying component) on the column selectivity, peak shape and overall chromatographic performance were evaluated. The RP-amide column, combined with a formic acid–acetonitrile based gradient system, performed as best. A peptide reversed-phase retention model is proposed, consisting of 5 variables: log SumAA, log Sv, clog P, log nHDon and log nHAcc. Quantitative structure-retention relationship (QSRR) models were constructed for 16 different chromatographic systems. The accuracy of this peptide retention model was demonstrated by the comparison between predicted and experimentally obtained retention times, explaining on average 86% of the variability. Moreover, using an external set of 5 validation peptides, the predictive power of the model was also demonstrated. This peptide retention model includes the novel in-silico calculated amino acid descriptor, AA, which was calculated from log P, 3D-MoRSE, RDF and WHIM descriptors.

Relative response factor determination of β-artemether degradants by a dry heat stress approach

During the stability evaluation of β-artemether containing finished drug products, a consistent and disproportional increase in the UV-peak areas of β-artemether degradation products, when compared to the peak area decline of β-artemether itself, was observed. This suggested that the response factors of the formed β-artemether degradants were significantly higher than β-artemether. Dry heat stressing of β-artemether powder, as a single compound, using different temperatures (125-150 °C), times (10-90 min) and environmental conditions (neutral, KMnO(4) and zinc), resulted in the formation of 17 degradants. The vast majority of degradants seen during the long-term and accelerated ICH stability study of the drug product, were also observed here. The obtained stress results allowed the calculation of the overall average relative response factor (RRF) of β-artemether degradants, i.e. 21.2, whereas the individual RRF values of the 9 most prominent selected degradants ranged from 4.9 to 42.4. Finally, Ames tests were performed on β-artemether as well as a representative stressed sample mixture, experimentally assessing their mutagenic properties. Both were found to be negative, suggesting no mutagenicity problems of the degradants at high concentrations. Our general approach and specific results solve the developmental quality issue of mass balance during stability studies and the related genotoxicity concerns of the key antimalarial drug β-artemether and its degradants.