Single Rice Grain Research Articles

Infrared microspectroscopy and machine learning: A novel approach to determine the origin and variety of individual rice grains

Accurately distinguishing the origin and variety of rice types is of paramount importance to conducting research on this staple crop. While various methods are currently employed for this purpose, few approaches can verify the identity of single grains rapidly and accurately. In this study, we present a method that integrates machine learning with infrared (IR) microspectroscopy for swift detection of the origin and variety of a single rice grain. To establish the validity of our approach, we assembled a diverse collection of rice samples, comprising 14 distinct types with different origins or varieties. Each rice sample yielded 100 microspectroscopy spectra, resulting in 1400 spectra. We applied two deep learning algorithms, deep neural network (DNN) and convolutional neural network (CNN), for spectral analysis. The 1400 spectra were randomly partitioned into calibration and validation sets at a ratio of 3:1. These datasets were subjected to both DNN and CNN analysis for classification of samples by origin and variety. Following 10,000 iterations, we selected optimal DNN and CNN models. The predication accuracies of the optimal DNN model for calibration and validation sets were 95.4% and 90.0%, respectively. In comparison, the optimal CNN model demonstrated superior accuracy, with 99.8% for the calibration set and 92.0% for the validation set. Based on these results, we selected the CNN model as the final model for field use in rice grain classification.

Late Bronze Age agriculture and the early westward transmission of rice at Luanzagangzi, Northern Xinjiang, China

The Dzungar Basin of northern Xinjiang has previously been considered a marginal environment with little evidence for the development of prehistoric agriculture. Recent archaeobotanical studies have indicated the region as being a route for the transmission of domesticated plants, technologies and ideas between East and West Eurasia during prehistory, as early as 5000 BP. These interactions are still poorly understood and most evidence for early plant food production and consumption in the region comes from limited mortuary contexts. In this study we present plant macrofossil analysis from the settlement site of Luanzagangzi on the southern side of the Dzungar Basin. From ca. 3130 BP an agricultural package of east and west Asian cereals and chaff is present, comprising wheat, barley, foxtail millet, broomcorn millet, and significantly a single grain of japonica type rice. AMS dating indicates this is the oldest directly dated rice in Xinjiang and the broader region, ranging 3069–2881 cal. BP. Cereal morphometrics and material culture from the site further indicate a connection with the Gansu region to the east. The spread of agriculture into the site environment may be linked to the onset of wetter conditions relating to strengthened westerly systems across arid Central Asia in the Late-Holocene. A declining abundance of West Asian cultivars over the period of the site’s occupation possibly reflect a shift away from intensive agriculture to low-level management of millets.

Rapid DNA template preparation directly from a rice sample without purification for loop-mediated isothermal amplification (LAMP) of rice genes.

Rapid DNA template preparation directly from a single rice (Oryza sativa) grain or rice flour of its equivalent weight was developed for loop-mediated isothermal amplification (LAMP). LAMP efficiency using DNA extract obtained from consecutive addition of alkaline lysis reagent (25 mM NaOH, 0.2 mM EDTA) and neutralizing reagent (40 mM Tris-HCl [pH 5]) was comparable to that using an equivalent amount of purified DNA as template. The stability of the prepared DNA extract was confirmed for up to six-day storage at room temperature. Without using any special laboratory devices, the developed method enabled a rapid, simple, and low-cost DNA template preparation method for reliable LAMP testing to detect rice genes.

Structural damage modes for rice stalks undergoing threshing

When rice stalk is impacted by the threshing bars during threshing process, the grain is separated but the rice stalk is also damaged. Damage of the rice stalk not only increases the energy consumption of process, but also results in small parts of the rice stalk being mixed with the grain increasing the difficulty of grain cleaning. The states of rice stalk before and after threshing were investigated by analysing the state response of rice stalks under the reaction of the threshing bars. The structural damage of rice stalks was analysed by comparing the relationship between the threshing force and the reaction tensile force, the bending force, and the pressing force during threshing. Damage modes were observed from the microstructure of rice stalks and rice leaves. The results showed that during rice stalk threshing, the force of the threshing bar was between 36.4 N and 121.0 N. Single rice grain and multiple grains are threshed, hollow stalks, stalk node and leaves are pressed damage and stalk root and stalk nodes maybe tensile damaged in threshing process. The microstructure of rice stalk following threshing was destroyed. The thin-walled tissues were completely deformed and the original structure was not visible. The main connections between the rice leaves were interrupted and flat, completely losing the normal shape of the original leaves. The research results revealed the level of the reaction force and microstructure damage of rice stalks. • Threshing force and reaction force reveals damaged distribution of rice stalk. • Rice stalk damage modes were obtained from microstructure after threshing. • Rice stalk is damaged during the process of grain threshing and separated.

Experimental benchmarking of diffusion and reduced models for convective drying of single rice grains

In this work, the drying behavior of single rice grains at moderate and elevated air temperatures (i.e. 60 °C, 120 °C, and 140 °C) is experimentally investigated by using a magnetic suspension balance system. To describe the experimental drying behavior, a diffusion model is developed. The reference moisture diffusivity of the rice grains is determined by using an inverse method, whereas other thermo-physical properties are measured. Next, the diffusion model is reduced to a semi-empirical model within the frame of reaction engineering approach (REA). Both models are successfully benchmarked against the experimental observations. The results indicate that the moisture diffusivity of rice grains can be represented as a linear function of the moisture content and the drying process at high temperatures is controlled by both intra- and extra-particle mass transfer resistances. In addition to these results, this study favors a practical application of the REA in drying calculations to derive a simple, robust, and extrapolative semi-empirical model since the parameter of this model seems to be insensitive to variations of drying conditions.

Simple and rapid detection of bisphenol A using a gold nanoparticle-based colorimetric aptasensor

A colorimetric aptasensor was developed for the simple and rapid detection of bisphenol A (BPA). The aptasensor was designed to consist of colloidal gold nanoparticles (AuNPs) and a BPA-specific 24-bp aptamer. The AuNP-aptamer conjugates underwent an electrolyte-induced aggregation in the presence of sub-ppb levels of BPA. The surface plasmon resonance shift of AuNPs facilitated a color change from red to blue upon aggregation, which was visually observed by the naked eye. The corresponding visual limit of detection of BPA was as low as 1 pg/mL (0.004 nM). The aptasensor also achieved a selective detection of BPA over a variety of BPA analogs. The applicability of the aptasensor was verified via a successful detection of BPA in a single grain of rice. This result indicates that the colorimetric aptasensor can be used in a screening procedure for food and environmental monitoring, with reliable performance to sub-ppb levels of BPA detection.

Generalized On-Demand Production of Nanoparticle Monolayers on Arbitrary Solid Surfaces via Capillarity-Mediated Inverse Transfer.

Century-old Langmuir monolayer deposition still represents the most convenient approach to the production of monolayers of colloidal nanoparticles on solid substrates for practical biological and chemical-sensing applications. However, this approach simply yields arbitrarily shaped large monolayers on a flat surface and is strongly limited by substrate topography and interfacial energy. Here, we describe a generalized and facile method of rapidly producing uniform monolayers of various colloidal nanoparticles on arbitrary solid substrates by using an ordinary capillary tube. Our method is based on an interesting finding of inversion phenomenon of a nanoparticle-laden air-water interface by flowing through a capillary tube in a manner that prevents the particles from adhesion to the capillary sidewall, thereby presenting the nanoparticles face-first at the tube's opposite end for direct and one-step deposition onto a substrate. We show that our method not only allows the placement of a nanoparticle monolayer at target locations of solid substrates regardless of their surface geometry and adhesion but also enables the production of monolayers containing nanoparticles with different size, shape, surface charge, and composition. To explore the potential of our approach, we demonstrate the facile integration of gold nanoparticle monolayers into microfluidic devices for the real-time monitoring of molecular Raman signals under dynamic flow conditions. Moreover, we successfully extend the use of our method to developing on-demand Raman sensors that can be built directly on the surface of consumer products for practical chemical sensing and fingerprinting. Specifically, we achieve both the pinpoint deposition of gold nanoparticle monolayers and sensitive molecular detection from the deposited region on clothing fabric for the detection of illegal drug substances, a single grain of rice and an orange for pesticide monitoring, and a $100 bill as a potential anti-counterfeit measure, respectively. We believe that our method will provide unique opportunities to expand the utility of colloidal nanoparticles and to greatly improve the accessibility of nanoparticle-based sensing technologies.

Differentiation of cultivation areas and crop years of milled rice using single grain mass spectrometry

A method for the rapid detection of fatty acids in single rice grain would make the evaluation of rice quality easier.

Continuous modeling of superheated steam drying of single rice grains

In this work, a transient macroscopic model is proposed for studying the conjugated heat and mass transfer phenomena that occur inside a single rice grain during the superheated steam drying process. The governing equations of this model are derived based on the volume-averaging approach. Since rice is a highly hygroscopic material, more than 80% of water is accumulated as bound water in rice grain. Both the bound water diffusive flow in the solid matrix and the convective flow of water vapor and liquid water in the void volume are taken into account in this model. Thermophysical properties of rice which serve as model inputs are measured, except the absolute permeability and the bound-water diffusivity coefficients. These two properties are determined by minimizing the square of residuals between simulation results and experimental data, which were obtained by means of a magnetic suspension balance system at a drying temperature of 160 °C. The validity of these two estimated parameters is reflected by a good agreement between the numerical and the experimental data at drying temperatures of 120 and 140 °C. Finally, a model-based sensitivity analysis is carried out, from which quantitative guidelines for the relationship between both the absolute permeability and the bound-water diffusivity and drying kinetics are proposed.

Analysis of four toxic metals in a single rice seed by matrix solid phase dispersion -inductively coupled plasma mass spectrometry.

Toxic metals in rice pose great risks to human health. Metal bioaccumulation in rice grains is a criterion of breeding. Rice breeding requires a sensitive method to determine metal content in single rice grains to assist the variety selection. In the present study, four toxic metals of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb) in a single rice grain were determined by a simple and rapid method. The developed method is based on matrix solid phase dispersion using multi-wall carbon nanotubes (MWCNTs) as dispersing agent and analyzed by inductively coupled plasma mass spectrometry. The experimental parameters were systematically investigated. The limits of detection (LOD) were 5.0, 0.6, 10 and 2.1 ng g−1 for As, Cd, Cr, and Pb, respectively, with relative standard deviations (n = 6) of <7.7%, demonstrating the good sensitivity and precision of the method. The results of 30 real world rice samples analyzed by this method agreed well with those obtained by the standard microwave digestion. The amount of sample required was reduced approximately 100 fold in comparison with the microwave digestion. The method has a high application potential for other sample matrices and elements with high sensitivity and sample throughput.

Elemental imaging and classifying rice grains by using laser ablation inductively coupled plasma mass spectrometry and linear discriminant analysis

This study aims to investigate elemental imaging in a longitudinal section of single rice grain using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and to classify rice according to their origins and types of 16 samples using LA-ICP-MS with linear discriminant analysis (LDA). The distributions of 8 essential elements (Ca, Cu, Fe, K, Mg, Mn, P and Zn) in a single rice grain were visualized as elemental images. Investigation of the elemental imaging of rice grain showed that essential elements were presented in large amounts in embryo and elevated level in endosperm. The elemental distributions of rice grain were not uniform. In addition, the concentration of 20 elements distributed in core endosperm was evaluated and used as chemical indicator to discriminate the origin and type of rice samples. The LDA can successfully differentiate rice samples according to their regions of origin (Northeast or South regions of Thailand) and types. Satisfied classifications are obtained with overall correct classification and cross-validation of 93.8% and 91.1% for origin classification and 100% and 97.9% for type classification.

Western blot detection of PMI protein in transgenic rice

Phosphomannose isomerase (PMI) encoding gene manA is a desirable selective marker in transgenic research. Understanding of its expression patterns in transgenic plant and establishing highly sensitive detection method based on immunoassay have great impacts on the application of PMI. In this study, PMI-specific monoclonal antibodies were generated using recombinant protein as immunogen, and could be used in Western blot to detect as little as 0.5 ng His-tagged PMI protein or rice expressed PMI protein in sample accounted for 0.4% of single rice grain (about 0.08 mg). PMI protein driven by CaMV-35S promoter was detected in dozens of tested tissues, including root, stem, leaf, panicle, and seed at all developmental stages during rice growing, and PMI protein accounted for about 0.036% of total protein in the leaves at seedling stage. The established method potentially can be used to monitor PMI protein in rice grains.

Observation and Measurement of Residual Bran on Milled Rice Using Hyperspectral Imaging

ABSTRACTResidual bran on milled rice is directly related to its quality. This study proposes a method to measure the residual bran patterns on a single rice grain by using hyperspectral imaging (HSI). HSI is a sensing technique that combines both spatial and spectral information and may be used for chemical compound identification and quantification. In this study, HSI was applied to assess rice bran residue nondestructively. In the experiment, rice samples were milled and scanned with an HSI system. Afterward, the rice samples were dyed to enable the residual bran to be identified with optical microscopy and image processing algorithms. Classifiers were then developed to predict the rice bran residue by using the HSI measurements as inputs. The predicted images were compared with the micrograph images for classifier performance evaluation. The proposed approach can estimate the residual bran distribution on milled rice surface with an accuracy of 93.5%.

Plant macro remains from Early Historic Vessel, Gilund, Rajasthan

The macrobotanical remains were recovered from the Early Historic vessel from Gilund, Rajasthan by employing dry and wet sieving techniques in the Palaeobotany laboratory. The retrieved archaeobotanical material was in carbonized and semi-carbonized state. It involves cultivated barley grains, a single cut grain of rice and a seeds of weed plant along with a bulk of wood charcoal pieces. These could survive in the carbonized state by being exposed to heat or fire. The impressions of grass leaves were found on well backed brickbats occurred in the vessel. Few molluscan shells were also retrieved during wet sieving.

A Small and Slim Coaxial Probe for Single Rice Grain Moisture Sensing

A moisture detection of single rice grains using a slim and small open-ended coaxial probe is presented. The coaxial probe is suitable for the nondestructive measurement of moisture values in the rice grains ranging from from 9.5% to 26%. Empirical polynomial models are developed to predict the gravimetric moisture content of rice based on measured reflection coefficients using a vector network analyzer. The relationship between the reflection coefficient and relative permittivity were also created using a regression method and expressed in a polynomial model, whose model coefficients were obtained by fitting the data from Finite Element-based simulation. Besides, the designed single rice grain sample holder and experimental set-up were shown. The measurement of single rice grains in this study is more precise compared to the measurement in conventional bulk rice grains, as the random air gap present in the bulk rice grains is excluded.

Using near-Infrared Spectroscopy to Investigate the Amylose Content in Rice

Nowadays, there are many breeding program to improve the quality of rice since the direct measurement (iodine colorimetric) is time consuming, complex and environmentally unfriendly. The objective of this study was to analyze the amylose content (AC) in several types of local rice and import rice in Malaysia. Next is to investigate suitable rice intake for diabetic patient. In this study, non-destructive method by using Near-Infrared Spectroscopy (NIRS) was used to measure the amylose content of single rice grain for milled rice and brown rice. The result showed that the AC for the brown rice was higher than basmati rice followed by local white rice. Therefore, the high amylose content is most suitable for the diabetic patient. Thus, NIRS was a convenient way to screen the quality of rice as well as increase the global competitive for farmers in agriculture field.

Measurement of Force for Detaching Single Grain of Rice

Measurement of Force for Detaching Single Grain of Rice

Drying Characteristics of a Single Grain of Rough Rice

Drying Characteristics of a Single Grain of Rough Rice

Measurement of Glass-Rubber Transition Temperature of Rice by Thermal Mechanical Compression Test (TMCT)

TMCT (Thermal Mechanical Compression Test) was applied to measure the Tg-r (glass-rubber transition temperature) of rice flour and individual rice kernels at low moisture content (2.4–19.5% wet basis). As expected, Tg-r decreased with increasing moisture content. The Tg-r temperatures measured by TMCT were comparable with those measured by DSC (Differential Scanning Calorimetry), TMA (Thermo-mechanical Analysis), and DMTA (Dynamic Mechanical Thermal Analysis) as reported in the literature. These results indicated that the TMCT technique could be applied to measure the glass-rubber transition of a single grain of rice or the rice in powder form. The sensitivity of the test was observed higher for the rice kernel than rice flour. TMCT technique has the advantage of usefulness and cost-effectiveness compared with the other techniques.

Micro-scaled high-throughput digestion of plant tissue samples for multi-elemental analysis

BackgroundQuantitative multi-elemental analysis by inductively coupled plasma (ICP) spectrometry depends on a complete digestion of solid samples. However, fast and thorough sample digestion is a challenging analytical task which constitutes a bottleneck in modern multi-elemental analysis. Additional obstacles may be that sample quantities are limited and elemental concentrations low. In such cases, digestion in small volumes with minimum dilution and contamination is required in order to obtain high accuracy data.ResultsWe have developed a micro-scaled microwave digestion procedure and optimized it for accurate elemental profiling of plant materials (1-20 mg dry weight). A commercially available 64-position rotor with 5 ml disposable glass vials, originally designed for microwave-based parallel organic synthesis, was used as a platform for the digestion. The novel micro-scaled method was successfully validated by the use of various certified reference materials (CRM) with matrices rich in starch, lipid or protein. When the micro-scaled digestion procedure was applied on single rice grains or small batches of Arabidopsis seeds (1 mg, corresponding to approximately 50 seeds), the obtained elemental profiles closely matched those obtained by conventional analysis using digestion in large volume vessels. Accumulated elemental contents derived from separate analyses of rice grain fractions (aleurone, embryo and endosperm) closely matched the total content obtained by analysis of the whole rice grain.ConclusionA high-throughput micro-scaled method has been developed which enables digestion of small quantities of plant samples for subsequent elemental profiling by ICP-spectrometry. The method constitutes a valuable tool for screening of mutants and transformants. In addition, the method facilitates studies of the distribution of essential trace elements between and within plant organs which is relevant for, e.g., breeding programmes aiming at improvement of the micronutrient density in edible plant parts. Compared to existing vial-in-vial systems, the new method developed here represents a significant methodological advancement in terms of higher capacity, reduced labour consumption, lower material costs, less contamination and, as a consequence, improved analytical accuracy following micro-scaled digestion of plant samples.