Identification, structure elucidation, and isomer differentiation of phenolic compounds of Chinese pepper cultivars by UPLC-ESI-Q-TOF-MS and their antioxidant activity.

A total of 43 compounds, including phenolic acids, flavonoids, lignans, and diterpene, were identified and characterized using UPLC-ESI-Q-TOF-MS coupled with UNIFI software. The identified flavonoids were mostly isomers of luteolin, apigenin, and quercetin, which were elucidated and distinguished for the first time in pepper cultivars. The use of multivariate data analytics for sample discrimination revealed that luteolin derivatives played the most important role in differentiating pepper cultivars. The content of phenolic acids and flavonoids in immature green peppers was generally higher than that of mature red peppers. The pepper extracts possessed significant antioxidant activities, and the antioxidant activities correlated well with phenolic contents and their molecular structure. In conclusion, the findings expand our understanding of the phytochemical components of the Chinese pepper genotype at two maturity stages. Moreover, a UPLC-ESI-Q-TOF-MS in negative ionization mode rapid methods for characterization and isomers differentiation was described.

Physicochemical properties, microstructure, and storage stability of Pulicaria jaubertii extract microencapsulated with different protein biopolymers and gum arabic as wall materials.

This study aimed to evaluate the possibility of using gum arabic (GA) with different protein materials namely whey protein isolate (WP), sodium caseinate (SC), and soybean protein (SP) as wall materials to encapsulate Pulicaria jaubertii extract (PJ) using freeze-drying. Four formulations of microencapsulation of Pulicaria jaubertii extract (MPJE) were produced, including WPGA-MPJE, SCGA-MPJE, SPGA-MPJE, and GA-MPJE. The formulations were stored at 4 °C and 25 °C for 28 days to assess the storage stability. The results indicated that mixtures of proteins with GA improved the physicochemical properties and bioactive content of the MPJE compared to GA-MPJE. The SCGA-MPJE formula showed optimal values of particle size (450.13 nm), polydispersity index (0.33), zeta potential (74.63 mV), encapsulation efficiency (91.07%), total phenolic content (25.51 g GAE g-1 capsules), and antioxidants compounds, as well as presented a lower release of bioactive composites with high oxidative stability during storage at 4 °C and 25 °C. The microstructure of MPJE formulations showed a flat surface without any visible cracking on surfaces. The microcapsules prepared from protein mixtures with GA, especially the SCGA-MPJE formula, are the most efficient in encapsulating the plant extract derived from the PJ, which could be useful for application in various industrial fields.

Nanoencapsulation of Mandarin Essential Oil: Fabrication, Characterization, and Storage Stability.

This study evaluates the combined efficiency of whey protein isolate (WPI) with maltodextrin (MD) and gum arabic (GA), as a delivery system for encapsulating Citrus reticulata essential oil (CEO). The wall materials blended at different rates were produced to obtain seven formulations of nanocapsules (NCEO), namely NCEO-GA, NCEO-MD, NCEO-WPI, NCEO-GA/MD, NCEO-GA/WPI, NCEO-MD/WPI, and NCEO-GA/MD/WPI. The interaction between CEO and WPI was simulated by molecular docking. Findings showed that the physicochemical characteristics and storage stability of formulations containing WPI were considerably improved. The NCEO-GA/MD/WPI formulation demonstrated the optimum values of encapsulation efficiency (92.08%), highest glass transition temperature (79.11 °C), high crystallinity (45.58%), high thermal stability (mass loss at 100 °C < 5%), and also had the highest antioxidant activity and lowest peroxide value after storage. This study demonstrated that combining WPI with MD and GA, as wall material encapsulation, can produce nanocapsules with superior properties to those created using polysaccharides individually.

Archaeal hyperthermostable mannitol dehydrogenases: A promising industrial enzymes for d-mannitol synthesis.

Recently, the term healthy lifestyle connected to low-calorie diets, although it is not possible to get rid of added sugars as a source of energy, despite the close relation of added sugars to some diseases such as obesity, diabetes, etc. As a result, the sweetener market has flourished, which has led to increased demand for natural sweeteners such as polyols, including d-mannitol. Various methods have been developed to produce d-mannitol to achieve high productivity and low cost. In particular, metabolic engineering for d-mannitol considers one of the most promising approaches for d-mannitol production on the industrial scale. To date, the chemical process is not ideal for large-scale production because of its multistep mechanism involving hydrogenation and high cost. In this review, we highlight and present a comparative evaluation of the biochemical parameters that affecting d-mannitol synthesis from Thermotoga neapolitana and Thermotoga maritima mannitol dehydrogenase (MtDH) as a potential contribution for d-mannitol bio-synthesis. These species were selected because purified mannitol dehydrogenases from both strains have been reported to produce d-mannitol with no sorbitol formation under temperatures (90-120 °C).

Microencapsulation of fingered citron extract with gum arabic, modified starch, whey protein, and maltodextrin using spray drying.

The aim of this study was to investigate the characteristics of the Fingered citron extract (FCE) microcapsules powders with different formulations of the encapsulation carrier agents [gum arabic (GA), maltodextrin (MD), modified starch (MS), and whey protein (WP)], which are obtained through spray drying. Encapsulation yield, encapsulation efficiency, moisture content, hygroscopicity, water activity, density properties, Carr's index, cohesiveness, flowability, porosity, wettability, solubility, color, particle size, thermal behavior, relative crystallinity, and micrographs were analyzed. Moreover, chemical structure of the microcapsule powder was identified using Fourier transform infrared spectroscopy (FT-IR). Best results were achieved when Fingered citron extract was encapsulated using gum arabic/maltodextrin/modified starch (GMS) formulation as carrier agents, where it had the highest encapsulation yield (89.39%) and encapsulation efficiency (87.20%). Furthermore, it achieved the best result in density properties, flowability, porosity, wettability, and relative crystallinity. These results have shown that using gum arabic/maltodextrin/modified starch formulation was superior for production of the Fingered citron extract microcapsules powders.

Preparation, deproteinization, characterization, and antioxidant activity of polysaccharide from Medemia argun fruit.

In this study, the crude polysaccharide from argun palm (Medemia argun) fruit was extracted with hot water and deproteinized by four different methods. Its structure characterization, thermal property and antioxidant activity were investigated by FT-IR spectroscopy, Scanning electron microscope, Congo-red, I2-KI, DPPH• assay, ABTS•+ assay, TGA and DSC analysis. It indicated that the NaCl method was the best method in deproteinization. The argun fruit polysaccharide linked by the ß-glycosidic bonds. The molecular weight of polysaccharide deproteinized with NaCl was 4.46 × 105 Da. It showed that the polysaccharide from argun palm fruit consisted of fructose, arabinose, rhamnose, galactose, glucose, xylose, and galacturonic acid. The result of TGA and DSC assay indicated that argun fruit polysaccharide has a favorable thermal stability. It was proved that, the argun fruit polysaccharide possessed high antioxidant activity and would be a new natural antioxidant.