Rapid HPLC Method for Determination of Isomaltulose in the Presence of Glucose, Sucrose, and Maltodextrins in Dietary Supplements

Multicomponent analysis of dietary supplements containing glucosamine and chondroitin: comparative low- and high-field NMR spectroscopic study

With the prevalence of glucosamine- and chondroitin-containing dietary supplements for people with osteoarthritis in the marketplace, it is important to have an accurate and reproducible analytical method for the quantitation of these compounds in finished products. NMR spectroscopic method based both on low- (80 MHz) and high- (500-600 MHz) field NMR instrumentation was established, compared and validated for the determination of chondroitin sulfate and glucosamine in dietary supplements. The proposed method was applied for analysis of 20 different dietary supplements. In the majority of cases, quantification results obtained on the low-field NMR spectrometer are similar to those obtained with high-field 500-600 MHz NMR devices. Validation results in terms of accuracy, precision, reproducibility, limit of detection and recovery demonstrated that the developed method is fit for purpose for the marketed products. The NMR method was extended to the analysis of methylsulfonylmethane, adulterant maltodextrin, acetate and inorganic ions. Low-field NMR can be a quicker and cheaper alternative to more expensive high-field NMR measurements for quality control of the investigated dietary supplements. High-field NMR instrumentation can be more favorable for samples with complex composition due to better resolution, simultaneously giving the possibility of analysis of inorganic species such as potassium and chloride.

Bioelectronic Tongues Mimicking Insect Taste Systems for Real-Time Discrimination between Natural and Artificial Sweeteners

A bioelectronic tongue (B-ET) mimicking insect taste systems is developed for the real-time detection and discrimination of natural and artificial sweeteners. Here, a carbon nanotube field-effect transistor (CNT-FET) was hybridized with nanovesicles including the honeybee sugar taste receptor, gustatory receptor 1 of Apis mellifera (AmGr1). This strategy allowed us to detect glucose, a major component of nectar, down to 100 fM in real time and identify sweet tastants from other tastants. It could also be utilized for the detection of glucose in dextrose tablet solutions. Importantly, we demonstrated the discrimination between natural and artificial sweeteners down to 10 pM even in real beverages such as decaffeinated coffee using our hybrid platform. In this respect, our B-ET mimicking insect taste systems can be a powerful tool for various applications such as food screening and basic studies on insect taste systems.

Bifunctional Fe@PCN-222 nanozyme-based cascade reaction system: Application in ratiometric fluorescence and colorimetric dual-mode sensing of glucose

This work innovatively integrated the peroxidase-mimicking activity and red emission property of Fe@PCN-222 framework, designed a cascade reaction system for dual-mode glucose sensing. The Fe³⁺ doping significantly improved the catalytic activity of Fe@PCN-222 that can oxidize the substrate o-phenylenediamine (OPD) to generate diminophenazine (DAP) with emission at 566 nm in the presence of H₂O₂. Similarly, the Fe@PCN-222 was used to catalyze the colorless TMB to produce blue oxidized TMB (oxTMB) showed absorption at 652 nm. When coupled with glucose oxidase (GOx), the linear ranges of ratiometric fluorescence mode and colorimetric mode for glucose sensing were 1-100 and 10-300 μM, respectively. And the limits of detection (LOD) of 0.78 and 2.41 μM for two modes were obtained, respectively. In addition, the practicability of Fe@PCN-222 nanozyme-based cascade reaction system for detection of glucose in human serum and saliva samples was successfully investigated. It is of great importance to integrate more functions into one skeleton to achieve dual-mode and optimal-performance sensing for expanding potential applications.

Investigation of the possibility of fermentation of red grape juice and rice flour by Lactobacillus plantarum and Lactobacillus casei

The aim of the current study was to evaluate the possibility of the bacterial growth and substrate metabolism during the fermentation of red grape juice and the mixture of red grape juice and rice flour solution using Lactobacillus plantarum and Lactobacillus casei. In recent years, cereal-based beverages have been used as functional compounds such as antioxidants, dietary fiber, minerals, probiotics, and vitamins in diets. In this research, fermentation of red grape juice (media 1) and 1:1 mixture of red grape juice and rice flour solution (media 2) by two strains of gram positive and homofermentative lactic acid bacteria: L. plantarum and L. casei (individually and mixed) was examined. Fermentation was carried out at 37°C for 48 hr. Microbial population, pH, acidity, sugar, and organic acid metabolism were measured during the fermentation period. Data showed that in media 2 fermented with mixed culture of both L. plantarum and L. casei, acidity and microbial population increased sharply at the initial stages of fermentation, and the most percentage of lactic acid production occurred. Red grape juice fermented with mixture of L. plantarum and L. casei showed the most sugar consumption (p < .05). Results indicated that the use of the mixture of red grape juice and rice flour solution can be a proper substrate for producing lactic acid.

Identification of a Biostimulating Potential of an Organic Biomaterial Based on the Botanical Extract from Arctium lappa L. Roots

The development of novel biomaterials based on plant extracts is expected to boost yields without adversely affecting environmental diversity. The potential biostimulating effects have so far been underreported. The assessment of the stimulating effect of botanical biomaterials is essential in the cultivation of economically-important crops. An attempt was undertaken in this study to develop a new biostimulating material in the form of granules, based on an extract from the roots of Arctium lappa L. The scope of the research included the characterization of the new material and the identification of its biostimulating potential. The designed and produced biogranulate is rich in bioactive compounds, including polyphenolic compounds, carbohydrates, and micro- and macro-elements. The analysis of the physicochemical properties of the biomaterial has shown that it had the features of intelligent biopreparations, i.e., slow-release preparations, at the pH appropriate for legume plants. Thus, knowledge about the design of new biomaterials is a milestone in the practical development of new perspectives for enhancing sustainability in agriculture.