Rapid Determination of Active Compounds and Antioxidant Activity of Okra Seeds Using Fourier Transform Near Infrared (FT-NIR) Spectroscopy

Abstract

Okra seeds (OSD) have been proved to possess significantly anti-fatigue activity and due to their high contents of flavonoids and polyphenols. While, the quality of OSD is easily affected by harvest time, region and other factors. In this research, the rapid method based on Fourier transform near infrared (FT-NIR) spectroscopy was developed for quality assessment of okra seeds. Firstly, 120 samples’ spectra were acquired, and quantification of isoquercitrin, quercetin-3-O-gentiobioside, total phenols (TP) and antioxidant assays including 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, ferric reducing antioxidant power (FRAP) were conducted. Next, partial least squares (PLS) regression and full cross-validation were applied to develop calibration models for these data, and external validation was used to determine models’ quality. The coefficient of determination for calibration (Rc2), the root mean square error of cross validation (RMSECV) and the corresponding determination coefficients for cross-validation (Rcv2) proved all these models have excellent precision. Besides, the residual predictive deviation (RPD) of models (4.07 for isoquercitrin, 4.04 for quercetin-3-O-gentiobioside, 9.79 for TP, 4.58 for DPPH and 4.12 for FRAP) also demonstrated that these models possessed good predicative ability. All these results showed that FT-NIR spectroscopy could be used to rapidly determine active compounds and antioxidant activity of okra seeds.

Abelmoschus esculentus (L.): Bioactive Components’ Beneficial Properties—Focused on Antidiabetic Role—For Sustainable Health Applications

“…The recent work of Xia et al [58] developed a rapid method based on Fourier transform near infrared (FT-NIR) spectroscopy for analysis of antioxidant compounds and activity of okra seeds. Another example was given by Zhang et al [59] that used near-infrared (874–1734 nm) hyperspectral imaging technology combined with chemometrics to identify parental and hybrid okra seeds.…”

Detection of the BRAF V600E Mutation in Colorectal Cancer by NIR Spectroscopy in Conjunction with Counter Propagation Artificial Neural Network

“…That is, the NIR absorption bands are seriously overlapping, so that NIR spectra are not directly interpreted and utilized. Thence, it is necessary to extract the information on the analytes from the NIR data for the sample by chemometric techniques [11,12,13]. NIR spectroscopy, assisted by chemometric techniques, is used to discriminate cancer from benign tumor, such as breast cancer [14], endometrial cancer [15], gastric cancer [16], and colorectal cancer [17], because it is easy-to-use, robust, inherently rapid (measuring a NIR spectrum in seconds), as well as nondestructive and low-cost [18,19].…”

Preliminary Study on the Identification of BRAFV600E Mutation in Colorectal Cancer by Near-Infrared Spectroscopy

“…37 For each molecular change, the absorbance of different wavelengths and the combination with stoichiometry technology will produce spectral data that can be mathematically processed to analyze and identify molecular changes. 35,36 Numerous…”

“…34 NIRS is often used for the determination of organic compounds containing these molecular. [35][36][37] NIRS is also widely used in bioassays or the determination of prostate-specific antigen 33 or in immunoassays. 38,39 Due to the advantages of NIRS, such as fast analysis speed, safety, non-destructive assessment of samples, and high accuracy, it can be used to identify benign tumors and cancers by examination of tissues, such as breast cancer, 40 endometrial cancer, 41 gastric cancer, 42 and CRC, 43 by combining NIRS with chemometrics.…”