Rapid Iodine Value Estimation Using a Handheld Raman Spectrometer for On-Site, Reagent-Free Authentication of Edible Oils

Fortified edible oils in Bangladesh: A study on vitamin A fortification and physicochemical properties

Food fortification has always been an effective and proven practice for eradicating various nutrient deficiencies in Bangladesh. This study investigated different quality parameters of three types (soybean, sunflower, and palm) of extensively consumed fortified edible oils in Bangladesh. Vitamin A analysis has shown that the vitamin A fortification level of most of the oil brands (73 %) did not comply with the Bangladesh Standard and Testing Institution (BSTI) standards (1.5-3.0 mg/100 g). Vitamin A contents of soybean, sunflower, and palm oil brands ranged from 0.13 to 2.06, 0.92-1.34, and 0.99-1.31 mg/100 g, respectively. Inter-brand values of vitamin A were also significantly different (p < 0.05). The majority of the samples were found to be within the acceptable ranges of Codex and BSTI, taking into account the significant chemical quality parameters for soybean, sunflower, and palm oil, such as acid value (0.31-0.93, 0.31-0.56, 0.39-0.81 mg KOH/g), free fatty acid (0.15-0.46, 0.15-0.28, 0.2-0.41 %), saponification (188.64-196.35, 186.53-188, 197.05-199.86 mg KOH/g), and peroxide values (0.06-2.9, 0.65-1.58, 1.35-1.75 meq O2/kg) respectively. All the brands' physical quality parameters (density, specific gravity, pH, viscosity, smoke point, color, and RI) complied with Codex standards. Various physical and chemical quality parameters were analyzed for significant correlations at 0.01 and 0.05 levels of significance. Remarkably, significant correlations were found between vitamin A and peroxide value (p < 0.01), iodine value and viscosity (p < 0.01), saponification value and viscosity (p < 0.01), pH and viscosity (p < 0.01), and saponification value and pH (p < 0.05). In conclusion, although the vitamin A status of most of the fortified edible oil brands was poor, the key quality indicators (except iodine value) of most of the oils were within the Codex and BSTI standard limits and were acceptable for human consumption.

Synthesis of Guanine/Vermiculite Two-Dimensional Nanocomposites for Wireless Humidity Sensing in Nut Storage Environment

Two-dimensional (2D) nanostructures have the advantages of high specific surface area, easy surface functionalization, abundant active sites, and good compatibility with device integration and can be assembled into three-dimensional structures, which are key to the development of high-performance gas sensors. In this study, 2D vermiculite (VMT) nanosheets and guanine (G), two renewable resources with unique chemical structures, were organically combined to fully use the specificity of their molecular structures and functional activities. Driven by the regulation of 2D VMT nanosheets, guanine/vermiculite (G/VMT)-based 2D nanocomposites with controllable pore structure, multiple binding sites, and unobstructed mass transfer were designed and synthesized. The G/VMT nanocomposite material was used as a quartz crystal microbalance (QCM) electrode-sensitive film material to build a QCM-based humidity sensor. G/VMT-based QCM humidity sensor had good logarithmic linear relation (0.9971), high sensitivity (24.49 Hz/% relative humidity), low hysteresis (1.75% RH), fast response/recovery time (39/6 s), and good stability. Furthermore, with a QCM sensor and a specially designed wireless circuit, a wireless humidity detection system transmitting via Wi-Fi allows real-time monitoring of nut storage. This study presents an environmentally friendly, high-performance, miniature 2D nanocomposite sensor strategy for real-time monitoring.

High-power ultrasound bleaching technique for canola oil (Brassica napus L.): Pigments removal and quality parameters

Canola seeds (Brassica napus L.) are among the most commonly used seeds in Mexico for vegetable oil production. This is based on the high yield and content of polyunsaturated and monounsaturated fatty acids. During oil bleaching, it is important to maintain fatty acids in their cis configuration because of the health concerns associated with trans-fatty acid consumption. In this sense, the industrial processing parameters employed for this purpose present some limitations, such as high temperatures and long times, which may change the cis configuration to trans. In addition, the amount of bleaching clay employed for this process could be a source of contamination because it is disposed of after treatment. Therefore, the aim of this study was to develop a bleaching process for canola oil using high-power ultrasound (US). US processing was applied to nine treatments with different processing times (60, 75, and 90 min), clay percentages (1, 2, and 3%), and temperatures (60 and 80 °C) to determine the concentrations of chlorophyll a and b (µg chlo/100 g oil), carotenes (µg β-carotene/100 g oil), color (L*, a*, b*, C*, and h°), iodine value (g I2/100 g oil), and finally carrying out a spectroscopic analysis (ATR-FTIR and Raman). A conventional bleaching treatment (100 °C for 180 min, 3% bleaching clay) was used as a control. The results revealed that US treatments with 2% clay at 60 °C for 60 and 90 min eliminated most of the chlorophyll compounds (98%). However, in terms of carotenes reduction, these identical treatments exhibited a similar tendency to that of the control (approximately 30% decrease). These findings also affected the sample color, in which US treatments revealed chromatic coordinates that indicated yellow tones with chroma values that were more intense than those in the control samples. In terms of the iodine value, such treatments fulfilled the international standards for vegetable oils (90-100 g I2/100 g oil). Finally, the spectroscopic study revealed no trans configurations or the presence of different chemical compounds after US treatment, because neither of them presented typical peaks for those molecular configurations. In this regard, US can be a useful methodology for bleaching vegetable oils, helping to reduce time, and bleaching clay with similar pigment reduction results.

Hogweed Seed Oil: Physico-Chemical Characterization, LC-MS Profile, and Neuroprotective Activity of Heracleum dissectum Nanosuspension

The seeds of dissected hogweed (Heracleum dissectum Ledeb., Apiaceae) are the source of hogweed oil (HSO), which is still underexplored and requires careful chemical and biological studies. The performed physico-chemical analysis of HSO elucidated basic physical characteristics and revealed the presence of fatty acids, essential oil components, pigments, and coumarins. High-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS) identified 38 coumarins that were characterized and quantified. Various furanocoumarins were the major components of HSO polyphenolics, including imperatorin, phellopterin, and isoimperatorin, and the total coumarin content in HSO varied from 181.14 to 238.42 mg/mL. The analysis of storage stability of the selected compounds in HSO indicated their good preservation after 3-year storage at cold and freezing temperatures. The application of the CO₂-assisted effervescence method allowed the production of an HSO nanosuspension, which was used in a brain ischemia model of rats. The HSO nanosuspension enhanced cerebral hemodynamics and decreased the frequency of necrotic processes in the brain tissue. Thus, H. dissectum seeds are a good source of coumarins, and HSO nanosuspension promotes neuroprotection of the brain after lesions, which supports earlier ethnopharmacological data.

Tetraplex Immunophenotyping of Cell Surface Proteomes via Synthesized Plasmonic Nanotags and Portable Raman Spectroscopy

Multiplex immunophenotyping of cell surface proteomes is useful for cell characterization as well as providing valuable information on a patient's physiological or pathological state. Current methods for multiplex immunophenotyping of cell surface proteomes still have associated technical pitfalls in terms of limited multiplexing capability, challenging result interpretation, and large equipment footprint limited to use in a laboratory setting. Herein, we presented a portable surface-enhanced Raman spectroscopy (SERS) assay for multiplex cell surface immunophenotyping. We synthesized and functionalized customizable SERS nanotags for cell labeling and subsequent signal measurement using a portable Raman spectrometer. We extensively evaluated and validated the analytical assay performance of the portable SERS immunophenotyping assay in two different cellular models (red blood cells and breast cancer cells). In terms of analytical specificity, the cell surface immunophenotyping of both red blood cells and breast cancer cells correlated well with flow cytometry. The portable SERS immunophenotyping assay also has comparable analytical repeatability to flow cytometry, with coefficient of variation values of 21.89-23.33% and 6.88-17.32% for detecting red blood cells and breast cancer cells, respectively. The analytical detection limits were 77 cells/mL for red blood cells and 1-17 cells/mL for breast cancer cells. As an alternative to flow cytometry, the portable SERS immunophenotyping assay demonstrated excellent analytical assay performance and possessed advantages such as quick sample-to-result turnaround time, multiplexing capability, and small equipment footprint.