Excavating the quantitative trait locus (QTL) associated with rice cooking quality, analyzing candidate genes, and improving cooking quality-associated traits of rice varieties by genetic breeding can effectively improve the taste of rice. In this study, we used the indica rice HZ, the japonica rice Nekken2 and 120 recombinant inbred lines (RILs) populations constructed from them as experimental materials to measure the gelatinization temperature (GT), gel consistency (GC) and amylose content (AC) of rice at the maturity stage. We combined the high-density genetic map for QTL mapping. A total of 26 QTLs associated with rice cooking quality (1 QTL associated with GT, 13 QTLs associated with GC, and 12 QTLs associated with AC) were detected, among which the highest likelihood of odd (LOD) value reached 30.24. The expression levels of candidate genes in the localization interval were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR), and it was found that the expression levels of six genes were significantly different from that in parents. It was speculated that the high expression of LOC_Os04g20270 and LOC_Os11g40100 may greatly increase the GC of rice, while the high expression of LOC_Os01g04920 and LOC_Os02g17500 and the low expression of LOC_Os03g02650 and LOC_Os05g25840 may reduce the AC. The results lay a molecular foundation for the cultivation of new high-quality rice varieties, and provide important genetic resources for revealing the molecular regulation mechanism of rice cooking quality.
Quantitative Trait Loci ; Oryza/genetics* ; Plant Breeding ; Cooking ; Genetic Association Studies

The present study aimed to investigate the effect of various adjuvant rice on the quality of rice-steamed Rehmanniae Radix(RSRR) with Japonica rice, millet, yellow rice, black rice, and glutinous rice as raw materials, and analyze the anti-osteoporosis effect of RSRR by the optimal adjuvant rice. On the basis of the established UPLC-MS/MS method for the determination of the content of catalpol and rehmannioside D, comprehensive weighted scoring method was employed to evaluate the effect of various auxiliary rice on the quality of RSRR with the content of catalpol and rehmannioside D, character score, and taste score as indicators to optimize adjuvant rice. The osteoporosis model was induced by ovariectomy in rats. SD rats were randomly divided into a sham operation group, a model group, a positive control group, and low-dose and high-dose groups of Rehmanniae Radix, RSRR, steamed Rehmanniae Radix, and Epimedii Folium-RSRR. After treatment for 12 weeks, body weight, bone calcium content, and bone mineral density were mea-sured. The results showed that Japonica rice was selected as the optimal adjuvant due to the highest comprehensive score of RSRR steamed by Japonica rice. Rehmanniae Radix, RSRR, steamed Rehmanniae Radix, as well as Epimedii Folium-RSRR, could improve osteoporosis by increasing bone calcium content and bone mineral density. RSRR was superior to Rehmanniae Radix in improving osteo-porosis. However, there was no significant difference between RSRR and steamed Rehmanniae Radix. This study confirmed that Japo-nica rice was the optimal adjuvant rice of RSRR and verified the anti-osteoporosis effect of RSRR, which laid a foundation for further research on the pharmacological action and mechanism of RSRR.
Female ; Rats ; Animals ; Oryza ; Chromatography, Liquid ; Calcium ; Rats, Sprague-Dawley ; Tandem Mass Spectrometry ; Drugs, Chinese Herbal/pharmacology* ; Osteoporosis/drug therapy* ; Rehmannia ; Adjuvants, Pharmaceutic

Zearalenone(ZEN) is a toxic metabolite produced by Fusarium culmorum, F. graminearum, F. tricinctum, and other fungi, with estrogenic characteristics. Exposure to or ingestion of ZEN during pregnancy can cause reproductive dysfunction, miscarriage, stillbirth, and malformation, and seriously endanger human life and health. The detection methods for ZEN in the Chinese Pharmacopoeia(2020 edition) are liquid chromatography(LC) and liquid chromatography-mass spectrometry(LC-MS), and it is stipulated that ZEN should not exceed 500 μg in 1 000 g of Coicis Semen. Although these detection methods by instruments can achieve the qualitative and quantitative analysis of ZEN in Coicis Semen, their high detection cost and long periods hinder the rapid screening of a large number of samples in the field. In this study, the synthesized ZEN hapten was conjugated with bovine serum albumin(BSA) and ovalbumin(OVA) to obtain the complete ZEN antigen. By virtue of antibody preparation techniques, ZEN monoclonal antibody 4F6 was prepared, which showed 177.5%, 137.1%, and 109.7% cross-reactivity with ZEN structural analogs zearalanol, zearalenone, and α-zearalenol, respectively, and no cross-reactivity with other fungal toxins such as aflatoxin. Direct competitive enzyme-linked immunosorbent assay(dcELISA) based on ZEN monoclonal antibody 4F6 was developed for the determination of ZEN in Coicis Semen with an IC_(50) of 1.3 μg·L~(-1) and a detection range of 0.22-21.92 μg·L~(-1). The recoveries were 83.91%-105.3% and the RSD was 4.4%-8.0%. The established dcELISA method was used to determine the ZEN residuals in nine batches of Coicis Semen samples, and the results were validated by LC-MS. The correlation between the two detection methods was found to be 0.993 9, indicating that the established dcELISA could be used for the rapid qualitative and quantitative detection of ZEN residuals in Coicis Semen.
Humans ; Female ; Pregnancy ; Zearalenone ; Coix ; Enzyme-Linked Immunosorbent Assay ; Mycotoxins ; Antibodies, Monoclonal

Recently, returning straw to the fields has been proved as a direct and effective method to tackle soil nutrient loss and agricultural pollution. Meanwhile, the slow decomposition of straw may harm the growth of the next crop. This study aimed to determine the effects of rumen microorganisms (RMs) on straw decomposition, bacterial microbial community structure, soil properties, and soil enzyme activity. The results showed that RMs significantly enhanced the degradation rate of straw in the soil, reaching 39.52%, which was 41.37% higher than that of the control on the 30th day after straw return. After 30 d, straw degradation showed a significant slower trend in both the control and the experimental groups. According to the soil physicochemical parameters, the application of rumen fluid expedited soil matter transformation and nutrient buildup, and increased the urease, sucrase, and cellulase activity by 10%‒20%. The qualitative analysis of straw showed that the hydroxyl functional group structure of cellulose in straw was greatly damaged after the application of rumen fluid. The analysis of soil microbial community structure revealed that the addition of rumen fluid led to the proliferation of Actinobacteria with strong cellulose degradation ability, which was the main reason for the accelerated straw decomposition. Our study highlights that returning rice straw to the fields with rumen fluid inoculation can be used as an effective measure to enhance the biological value of recycled rice straw, proposing a viable solution to the problem of sluggish straw decomposition.
Animals ; Rumen/metabolism* ; Agriculture/methods* ; Soil/chemistry* ; Microbiota ; Bacteria/metabolism* ; Oryza/metabolism* ; Soil Microbiology ; Cellulose

Iron (Fe) deficiency and excess cadmium (Cd) in rice grain are important problems to be solved in agricultural production. Previous studies have shown that OsVIT1 and OsVIT2 are vacuolar iron transporters. In this study, wild-type ZH11 was selected as the background material and OsVIT1 and OsVIT2 were overexpressed in endosperm by using endosperm specific promoter Glb-1. Field experiments were conducted to study the effect of OsVIT1 and OsVIT2 overexpression on Fe and Cd accumulation in different parts of rice. The results showed that OsVIT1 overexpression in endosperm significantly reduced Fe content in grain by about 50%, while significantly increased zinc (Zn) and copper (Cu) contents in straw and Cu content in grain. OsVIT2 overexpression in endosperm significantly decreased Fe and Cd contents in grain by about 50%, and significantly increased Fe content in straw by 45%-120%. Overexpression of OsVIT1 and OsVIT2 in endosperm did not affect the agronomic traits of rice. In conclusion, OsVIT1 and OsVIT2 overexpression in endosperm reduced Fe accumulation in rice grain, which did not achieve the expected effect. OsVIT2 overexpression in endosperm also decreased Cd accumulation in grain and increased Fe accumulation in straw, which provided reference for iron biofortification and cadmium reduction in rice.
Cadmium ; Endosperm/chemistry* ; Oryza/genetics* ; Iron ; Zinc ; Edible Grain ; Soil Pollutants

In this study, a new Bacillus velezensis strain Bv-303 was identified and its biocontrol effect against rice bacterial-blight (BB) disease caused by Xanthomonas oryzae pv. oryzae (Xoo) was investigated. Cell-free supernatant (CFS) of strain Bv-303 under different growth conditions were prepared to test the antagonistic activity and stability against Xoo by the Oxford-cup method in vitro. The antibacterial effect of strain Bv-303 to BB disease in rice were further analyzed in vivo by spraying the cell-culture broth (CCB), CFS and cell-suspension water (CSW), respectively, on the rice leaves inoculated with Xoo. Additionally, rice seeds germination rate and seedling growth under the strain Bv-303 CCB treatment were tested. The results showed that the strain Bv-303 CFS significantly inhibited Xoo growth by 85.7%‒88.0% in vitro, which was also stable under extreme environment conditions such as heat, acid, alkali and ultraviolet light. As tested in vivo, spraying the CCB, CFS or CSW of strain Bv-303 on the Xoo-infected leaves enhanced rice plant resistance to BB disease, with CCB showing the highest increase (62.7%) in disease-resistance. Notably, CCB does not have negative effects on rice seed germination and seedling growth. Therefore, strain Bv-303 has great potential for biocontrol of the rice BB disease.
Oryza ; Fatigue Syndrome, Chronic ; Bacillus ; Xanthomonas ; Plant Diseases/microbiology*

Biorefinery of chemicals from straw is an effective approach to alleviate the environmental pollution caused by straw burning. In this paper, we prepared gellan gum immobilized Lactobacillus bulgaricus T15 gel beads (LA-GAGR-T15 gel beads), characterized their properties, and established a continuous cell recycle fermentation process for D-lactate (D-LA) production using the LA-GAGR-T15 gel beads. The fracture stress of LA-GAGR-T15 gel beads was (91.68±0.11) kPa, which was 125.12% higher than that of the calcium alginate immobilized T15 gel beads (calcium alginate-T15 gel beads). This indicated that the strength of LA-GAGR-T15 gel beads was stronger, and the strain was less likely to leak out. The average D-LA production was (72.90±2.79) g/L after fermentation for ten recycles (720 h) using LA-GAGR-T15 gel beads as the starting strain and glucose as the substrate, which was 33.85% higher than that of calcium alginate-T15 gel beads and 37.70% higher than that of free T15. Subsequently, glucose was replaced by enzymatically hydrolyzed corn straw and fermented for ten recycles (240 h) using LA-GAGR-T15 gel beads. The yield of D-LA reached (1.74±0.79) g/(L·h), which was much higher than that of using free bacteria. The wear rate of gel beads was less than 5% after ten recycles, which indicated that LA-GAGR is a good carrier for cell immobilization and can be widely used in industrial fermentation. This study provides basic data for the industrial production of D-LA using cell-recycled fermentation, and provides a new way for the biorefinery of D-LA from corn straw.
Fermentation ; Lactobacillus delbrueckii ; Zea mays ; Lactic Acid ; Alginates/chemistry* ; Glucose

By investigating the contamination status and predicting the exposure risk of mycotoxin in Coicis Semen, we aim to provide guidance for the safety supervision of Chinese medicinal materials and the formulation(revision) of mycotoxin limit standards. The content of 14 mycotoxins in the 100 Coicis Semen samples collected from five major markets of Chinese medicinal materials in China was determined by UPLC-MS/MS. The probability evaluation model based on Monte Carlo simulation method was established after Chi-square test and One-way ANOVA of the sample contamination data. Health risk assessment was performed on the basis of margin of exposure(MOE) and margin of safety(MOS). The results showed that zearalenone(ZEN), aflatoxin B_1(AFB_1), deoxynivalenol(DON), sterigmatocystin(ST), and aflatoxin B_2(AFB_2) in the Coicis Semen samples had the detection rates of 84%, 75%, 36%, 19%, and 18%, and the mean contamination levels of 117.42, 4.78, 61.16, 6.61, and 2.13 μg·kg~(-1), respectively. According to the limit standards in the Chinese Pharmacopoeia(2020 edition), AFB_1, AFs and ZEN exceeded the standards to certain extents, with the over-standard rates of 12.0%, 9.0%, and 6.0%, respectively. The exposure risks of Coicis Semen to AFB_1, AFB2, ST, DON, and ZEN were low, while 86% of the samples were contaminated with two or more toxins, which needs more attention. It is suggested that the research on the combined toxicity of different mycotoxins should be strengthened to accelerate the cumulative exposure assessment of mixed contaminations and the formulation(revision) of toxin limit standards.
Humans ; Mycotoxins/analysis* ; Coix ; Aflatoxin B1/analysis* ; Chromatography, Liquid/methods* ; Food Contamination/analysis* ; Tandem Mass Spectrometry/methods*

This study compared the changes in chemical components during the processing of different types of Aconiti Lateralis Radix Praeparata(ALRP) in "Jianchang" faction, i.e., dried ginger-steamed ALRP pieces(Yin-FP), sand-fried ALRP pieces(Yang-FP), and rice swill water-bleached ALRP pieces(DFP), and provided a scientific basis for the mechanism in toxicity reduction and efficacy enhancement from a compositional perspective. Samples were collected during the processing of the three types of ALRP pieces, yielding raw ALRP pieces, water-bleached Yin-FP, ginger juice-moistened Yin-FP, steamed Yin-FP, water-bleached Yang-FP, sand-fried Yang-FP, water-bleached DFP, rice swill water-bleached DFP, and roasted DFP. Aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine, aconine, mesaconine, hypaconine, salsolinol, fuziline, and higenamine in the extracts were determined by UPLC-MS/MS, and then content analysis and cluster heatmap analysis were performed on 11 sets of samples. During the processing of the three types of ALRP pieces, bleaching significantly reduced the content of 12 alkaloids; steaming, stir-frying, and roasting significantly reduced the content of diester-type alkaloids(aconitine, mesaconitine, and hypaconitine) and significantly increased the content of monoester-type alkaloids(benzoylaconine, benzoylmesaconine, and benzoylhypaconine) and aminoalcohol-type alkaloids(aconine, mesaconine, and hypaconine). During the processing of Yin-FP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. During the processing of Yin-FP, Yang-FP, and DFP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. Steamed Yin-FP showed a higher increase in content than fried Yang-FP and roasted DFP. Comprehensive analysis of content differences in toxic and therapeutic components in three ALRP pieces suggests that the distinctive processing methods in "Jianchang" faction can indeed achieve detoxification and efficacy enhancement on ALRP. This study provides references for understanding the mechanisms of action of the three processing methods.
Aconitine/analysis* ; Tandem Mass Spectrometry ; Zingiber officinale ; Oryza ; Sand ; Liquid Chromatography-Mass Spectrometry ; Chromatography, Liquid ; Drugs, Chinese Herbal/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Alkaloids/analysis* ; Steam

Male ; Humans ; Avena ; Infertility, Male/genetics* ; Oligospermia/genetics* ; Asthenozoospermia ; Spermatozoa