Genome-wide association study reveals useful QTL and genes controlling the fatty acid composition in rice bran oil using Vietnamese rice landraces.

In rice (Oryza sativa L.), rice bran contains valuable nutritional constituents, such as high unsaturated fat content, tocotrienols, inositol, γ-oryzanol, and phytosterols, all of which are of nutritional and pharmaceuticals interest. There is now a rising market demand for rice bran oil, which makes research into their content and fatty acid profile an area of interest. As it is evident that lipid content has a substantial impact on the eating, cooking, and storage quality of rice, an understanding of the genetic mechanisms that determine oil content in rice is of great importance, equal to that of rice quality. Therefore, in this study, we performed a genome-wide association study on the composition and oil concentration of 161 Vietnamese rice varieties. Five categories of fatty acids in rice bran were discovered and the bran oil concentration profile in different rice accessions was identified. We also identified 229 important markers related to the fatty acid composition of bran oil, distributed mainly on chromosomes 1 and 7. Seven quantitative trait loci and five potential genes related to unsaturated fatty acid content were detected, including OsKASI, OsFAD, OsARF, OsGAPDH, and OsMADS29. These results provide insights into the genetic basis of rice bran oil composition, which is pivotal to the metabolic engineering of rice plants with desirable bran oil content through candidate genes selection.

Genotypic and Phenotypic Diversity of Endemic Golden Camellias Collected from the North of Vietnam.

Golden Camellias have recently been used as a food, cosmetic, and traditional medicine in China and Vietnam. Forty-two species have natural distribution in Vietnam, of which thirty-two species were considered endemic species of this country. The morphology of leaves and flowers of these species were similar; therefore, their taxonomic identification usually needed experts and the authentication has often been confused among species. Our study aims to describe the genetic diversity and the relationship of six species Camellia phanii, Camellia tamdaoensis, Camellia tienii, Camellia flava, Camellia petelotii and Camellia euphlebia by using three chloroplast DNA-barcodes: matK, rbcL and trnH-psbA. We also clarified the significant differences in anatomical characteristics of midvein and blade of their leaves, which suggested the possibility to use these criteria in taxonomy. In addition, preliminary chemical profiles of the methanolic extracts of leaves from six Golden Camellias such as total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC) and chlorogenic acids content (TCGAs) also showed the diversity among them. Interestingly, the discrimination on the catechins profile among six species followed the same tendency with the genetic distance on the phylogeny tree suggesting that catechins (i. e., discriminative catechins) can be biomarkers for the chemotaxonomy of these six Golden Camellias.

A genome-wide association study reveals the quantitative trait locus and candidate genes that regulate phosphate efficiency in a Vietnamese rice collection.

The crucial role of phosphate (Pi) for plant alongside the expected depletion of non-renewable phosphate rock have created an urgent need for phosphate-efficient rice varieties. In this study, 157 greenhouse-grown Vietnamese rice landraces were treated under Pi-deficient conditions to discover the genotypic variation among biochemical traits, including relative efficiency of phosphorus use (REP), relative root to shoot weight ratio (RRSR), relative physiological phosphate use efficiency (RPPUE), and relative phosphate uptake efficiency (RPUpE). Plants were grown in Yoshida nutrient media with either a full (320 µM) or a low Pi supply (10 µM) over six weeks. This genome-wide association study led to the discovery of 31 significant single nucleotide polymorphisms, 18 quantitative trait loci (QTLs), and 85 candidate genes. A common QTL named qRPUUE9.16 was found among the three investigated traits. Some interesting candidate genes, such as PLASMA MEMBRANE PROTEIN1 (OsPM1), CALMODULIN-RELATED CALCIUM SENSOR PROTEIN 15 (OsCML15), phosphatases 2C (PP2C), STRESS-ACTIVATED PROTEIN KINASE (OsSAPK2), and GLYCEROPHOSPHORYL DIESTER PHOSPHODIESTERASES (GDPD13), were found strongly correlated to the Pi starvation. RNA sequencing transcriptomes revealed that 45 out of 85 candidate genes were significantly regulated under Pi starvation. Furthermore, nearly two-thirds of genotypes did not possess the OsPsTOL1 gene; however, no significant difference was observed in response to Pi deficiency between genotypes with or without this gene, suggesting that other QTLs in rice may resist Pi starvation. These results provide new information on the genetics of nutrient use efficiency in rice and may potentially assist with developing more phosphate-efficient rice plants.

Polyacrylate crosspolymer-11 enhances soil clay dispersibility: An indication for inadvertent environmental impacts from personal care and cosmetic ingredients.

Polymer ingredients are commonly found in personal care and cosmetic industry and their "leakages" into the environment have recently been warned as an emerging environmental risk. Daily use of personal care and cosmetic products can inadvertently release large amounts of polymer ingredients into water courses. However, their fate and interaction with other constituents, especially colloids (e.g., clays), have not been fully understood. This study primarily evaluates the colloidal dynamics of soil clays under the presence of polyacrylate crosspolymer-11 (PC11) (a common ingredient of cosmetic and personal care products) with the aim of identifying possible induced changes in the clay-accumulated environments, e.g., soil and sediment. The test-tube experiments were coupled with a particle charge detector to mutually evaluate the colloidal dynamics and surface charge properties of the soil clays. It was revealed that adsorption of PC11 onto the clays shifted clay surface to more negative, thereby intensifying repulsive force and favouring the dispersion state of the soil clays. This implies that various polymer ingredients can act in the same way in stabilizing clay dispersion or even altering the fate of the soil clays. As the growing consumption of personal care and cosmetic products will likely continue, it requires a tighter consideration of the possible impacts of polymer ingredient residues, not limited to dispersion-induced effects, in various clay-accumulated environments such as paddy fields, river mouths or mangroves.

Evolution of physico-chemical properties of Dicranopteris linearis-derived activated carbon under various physical activation atmospheres.

This work emphasizes the effect of the physical activation using CO2 and steam agents on the physicochemical properties of activated carbon produced from Dicranopteris linearis (D. linearis), a fern species widely distributed across tropic and subtropic ecoregions. The D. linearis-derived chars produced under pyrolysis at 400 °C for 1 h were activated in various CO2-steam proportions. As revealed by the IR and Raman spectra, the structure of the activated chars was heavily dependent on the relative proportion of CO2 and steam. The total specific surface area (SSA) of the activated chars proportionally increased with the increase in steam proportion and was comparable to the values of commercial activated char products. Specifically, the activation under CO2- and steam-saturated conditions has correspondingly resulted in SSA increasing from 89 to 653 m2g-1 and from 89 to 1015 m2g-1. Steam also enhanced the development of mesoporous structures of the D. linearis-derived char products, thereby extending their potential applications, particularly for industries that require high rigidity in the product such as pharmaceutical and cosmetic sectors.

Discovery of new genetic determinants of morphological plasticity in rice roots and shoots under phosphate starvation using GWAS.

Phosphorus is an essential nutrient for plants that is often in short supply. In rice (Oryza sativa L.), inorganic phosphate (Pi) deficiency leads to various physiological disorders that consequently affect plant productivity. In this study, a large-scale phenotyping experiment using 160 Vietnamese rice landraces was performed under greenhouse conditions, by employing an alpha lattice design with three replicates, to identify quantitative trait loci (QTLs) associated with plant growth inhibition caused by Pi deficiency. Rice plantlets were grown for six weeks in the PVC sand column (16 cm diameter × 80 cm height) supplied with Pi-deficient medium (10 µM P) or full-Pi Yoshida medium (320 µM P). The effects of Pi deficiency on the number of crown roots, root length, shoot length, root weight, shoot weight and total weight were studied. From 36 significant markers identified using a genome-wide association study, 21 QTLs associated with plant growth inhibition under Pi starvation were defined. In total, 158 candidate genes co-located with the defined QTLs were identified. Interestingly, one QTL (qRST9.14) was associated with all three weight-traits. The co-located gene GLYCEROPHOSPHODIESTER PHOSPHODIESTERASE 13 was found to be potentially involved in Pi transport. Understanding the molecular mechanisms of Pi-starvation responses, and identifying the potential QTLs responsible for low-Pi stress tolerance, will provide valuable information for developing new varieties tolerant of low-Pi conditions.

Arabidopsis Hairy Roots Producing High Level of Active Human Gastric Lipase.

Arabidopsis hairy roots were used to produce human gastric lipase. When treated with 2,4-D, the hairy roots developed into thick organs that produced more protein than untreated roots. This was first assessed using green fluorescent protein-producing root lines from which the protein diffused into the culture medium. When growing hairy roots which express the human gastric lipase gene, very little lipase was found in the medium. Incubating the roots in a low pH buffer resulted in lipase diffusion into the buffer, avoiding the need for grinding. The activity of the enzyme on 4-methylumbellireryl-oleate and on tributyrin was determined. Approximately 6000 units of enzyme were recovered per gram of root. The enzyme was also extracted from freeze-dried roots before and after a 2-month storage period at room temperature. This work demonstrates the relevance of Arabidopsis hairy roots for the production of human gastric lipase.

Carbonization and H3PO4 activation of fern Dicranopteris linearis and electrochemical properties for electric double layer capacitor electrode.

Today, the world's climate change is a growing problem, plant carbon sequestration is one of the effective ways to mitigate climate change by reducing greenhouse gases, mostly carbon gases. Dicranopteris linearis (D. linearis), a common fern species in the tropic or subtropic ecoregions, has been recently recognized as a potential feedstock to produce highly porous biochar. This study aims to enhance the specific surface area (SSA) and pore volumes of biochars derived from the D. linearis by H3PO4 activation and examine electrical properties of the activated biochars and their possible usage for the electric double-layer capacitor (EDLC) electrode. The treated raw fern was activated with H3PO4 85% by the three different mixing ratios 1:0, 1:1, and 1:3 (w/w) and then pyrolysis under N2 flow maintained at 500 °C for 1 h. The performance as the electrode for an EDLC was evaluated in 1 mol L-1 H2SO4 solution for the H3PO4-activated samples. The SSA and pore volumes were drastically increased after activation. The maximum SSA and pore volume were 1212 m2 g-1 and 1.43 cm3 g-1, respectively for the biochar activated at 400 °C with a weight mixing ratio 1:3 (w/w) between the fern and H3PO4 acid while these values of the biochar at 400 °C were 12 m2 g-1 and 0.02 cm3 g-1, respectively. The biochar activated at 600 °C with the mixing ratio 1:1 (w/w) showed the maximum capacitance value, ca. 108 F g-1 at 1 mV s-1. The activation using H3PO4 showed a positive tendency to enhance electrochemical properties and it could be a premise toward a higher performance of EDLC from the D. linearis derived activated biochar.

Colloidal interactions of micro-sized biochar and a kaolinitic soil clay.

Fine-sized biochars and clay minerals co-present in various circumstances, e.g., agricultural land and water treatment. Because both of these materials are scavengers for nutrients, agrochemicals and other toxicants, their dispersibility and transportability have received much attention. However, little is documented about their colloidal interactions and to what extent biochar particles can stimulate the dispersion of clay minerals. Here, the effect of engineered micro-sized biochar amendment on the surface charge (SC) and colloidal dynamics of the clay fraction of a kaolinite-rich soil was determined. The engineered biochars showed distinctive SC and colloidal properties depending on their pyrolysis conditions (e.g., oxygen level and temperature) and solution chemistry (i.e., pH and cation type). Two types of biochars prepared under non-biochar-oriented pyrolysis (open heating, 'O-biochar') and biochar-oriented pyrolysis (N2-supported heating, 'N2-biochar') showed contrasting effects on the colloidal dynamics of clay. The O-biochars provoked aggregation due to their higher content of soluble salts, which increased ionic strength and provided multivalent cations, inducing bridging between negatively charged colloids. In contrast, the N2 biochars low in soluble salts and rich in negatively charged burned organic matter compounds favoured the dispersion of clay. The adjustment of biochar production methods can therefore be highlighted as the way to customize biochar for specific uses or to reduce the risk of clay loss from soils in the short term. In the long term, when soluble salts are removed by leaching, it is likely that dispersion is facilitated and the risk for erosion increases.

Food for thought. What you eat depends on your sex and eating companions.

In a naturalistic study, we investigated the influence of gender, group size and gender composition of groups of eaters on food selected for lunch and dinner (converted to total calories per meal) of 469 individuals (198 groups) in three large university cafeterias. In dyads, women observed eating with a male companion chose foods of significantly lower caloric value than those observed eating with another woman. Overall, group size was not a significant predictor of calories, but women's calories were negatively predicted by numbers of men in the group, while the numbers of women in the group had a marginally significant positive impact on calorie estimates. Men's calorie totals were not affected by total numbers of men or women. This study supports previous investigations, but is unique in making naturalistic observations.