The possibility of applying near-infrared (NIR) spectroscopy to monitor 13 active components (phenolic acids, flavonoids, and sesquiterpene lactones) in was studied. The preprocessing of the spectra were performed by using the conventional Golay-Savitzky procedure and the newly developed step-by-step filter. The results obtained show that the step-by-step filter derivatives provide a better signal-to-noise ratio at a lower convolution window. Better calibration for the content of protocatechuic acid, chlorogenic acid, caffeic acid, p-cumaric acid, ferulic acid, isoquercitrin, and quercetin were obtained by step-by-step filter derivatives, compared to the direct raw spectra processing and the Golay-Savitzky approach. Although the step-by-step filter substantially reduces the spectral distortion, the convolution procedure leads to loss of spectral points in the red end of the spectral curve. Probably for this reason this approach shows better calibration only in seven of the monitored 13 active components.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6352279PMC
http://dx.doi.org/10.3390/foods8010009DOI Listing

Publication Analysis

Top Keywords

step-by-step filter
16
nir spectroscopy
8
active components
8
filter derivatives
8
better calibration
8
acid
5
quantitative characterization
4
characterization rp-hplc-uv
4
rp-hplc-uv nir
4
spectroscopy possibility
4

Similar Publications

Microwave phase detectors (MPDs) are key components of instantaneous frequency measurement (IFM) receivers and phase interferometer direction finding (PIF-DF) receivers. In conventional analyses, there is seldom a major quantitative discussion of MPD characterization when multiple signals arrive at the same time, which is often the case in complex and noisy electromagnetic environments. We have reanalyzed the characteristics of MPDs with respect to filter effects acting on more than two RF signals and differential amplifiers, which are not considered in conventional analyses.

View Article and Find Full Text PDF

Cryo-electron microscopy (cryo-EM) is a powerful technique capable of investigating samples in a hydrated state, compared to conventional high-vacuum electron microscopy that requires samples to be completely dry. During the drying process, numerous features and details may be lost due to damage caused by dehydration. Cryo-EM circumvents these problems by cryo-fixing the samples, thereby retaining the intact and original features of hydrated samples.

View Article and Find Full Text PDF

A new sample preparation and determination method, including HPLC-DAD analysis after Magnetic Solid Phase Extraction (MSPE), was developed to monitor the trace amounts of two types of nonsteroidal anti-inflammatory drugs (NSAIDs), Ibuprofen (IBP) and Ketoprofen (KP). In the proposed method, IBP and KP analytes were extracted from newly synthesized magnetic-based sorbent in a pH 4.0 buffer medium and enriched by desorbing again with ethanol to a smaller volume before chromatographic determinations.

View Article and Find Full Text PDF

Tandem Imaging of Breath Ethanol and Acetaldehyde Based on Multiwavelength Enzymatic Biofluorometry.

ACS Sens

December 2024

Department of Biomedical Devices and Instrumentation, Laboratory for Biomaterials and Bioengineering, Institute of Integrated Research, Institute of Science Tokyo, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.

Highly sensitive and selective imaging of human-borne volatile organic compounds (VOCs) enables an intuitive understanding of their concentrations and release sites. While multi-VOC imaging methods have the potential to facilitate step-by-step metabolic tracking and improve disease screening accuracy, no such system currently exists. In this study, we achieved simultaneous imaging of ethanol (EtOH) and acetaldehyde (AcH), the starting molecule and an intermediate metabolite of alcohol metabolism, using a multiwavelength VOC imaging system.

View Article and Find Full Text PDF

This study presents a high-power, single-longitudinal-mode (SLM) fiber oscillator with a ring cavity design, operating at 1064 nm. Utilizing a double-cladding ytterbium-doped fiber as the gain medium, the system incorporates a fiber Bragg grating Fabry-Perot cavity and a dual coupler ring for step-by-step filtering to achieve SLM operation. With a pump power of 4.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!