The main nutrients in rice are starch, protein and lipids, and their contents and physicochemical properties have important effects on rice qualities. The aging process of rice is very complex, which not only changes physical and chemical properties, but also changes its physiological characteristics in rice grain. In this paper, the changes of physicochemical properties of its main nutrients (starch, protein and lipids) during storage were reviewed. At the same time, the effects of rice aging on its quality characters and the mechanism of rice aging were also discussed, which could provide reference for solving the problem of rice quality decline during storage.

Residues of the pesticides chlorfenapyr (CFP) and emamectin benzoate (EMB) often coexist in the environment and can be accumulated in the body. To understand the impact of these two chemicals on health, we investigated their effect on the kidneys. In this study, rats were treated with CFP and/or EMB at low/medium/high doses of 1/3/9 mg/kg/day and 0.2/0.6/1.8 mg/kg/day, respectively, via oral gavage for 60 days. Kidneys and serum samples were collected and serum biochemistry and kidney histopathological changes were analyzed and examined. Kidney metabolome alterations were analyzed by using gas chromatography–mass spectrometry. The results showed that combined exposure to CFP and EMB elevated BUN levels and induced pathological damage, which presented as thinner renal tubular epithelial cells, an abnormal glomerular morphology, and an increased fibrotic area. CFP and/or EMB disrupted glutathione metabolism and carbohydrate metabolism, resulting in the alteration of kidney metabolomes and inducing oxidative stress in the cells of kidney tissues. In addition, CFP decreased ATP content and inhibited pyruvate PDH activity in the kidneys. These findings suggest that long-term exposure to CFP and EMB at environmentally relevant levels induce alterations in the renal metabolome, oxidative stress, and an insufficient energy supply, which may contribute to renal histopathological damage.

Some organophosphorus compounds can induce delayed neurotoxicity, which is characterized by ataxia, also known as organophosphate-induced delayed neurotoxicity (OPIDN). The underlying mechanism of axonal degeneration and demyelination in OPIDN is still poorly understood, although progress on the studies has been made. Progesterone is an important sex hormone with a neuroprotective effect, and a decrease in progesterone level was observed in the hens with OPIDN. To investigate whether exogenous progesterone offers protective effects in OPIDN and to elucidate the underlying mechanisms, we conducted an investigation with adult hens, which is the typical model animal for OPIDN research. The hens were either administrated with a single dose of the classical OPIDN inducer tri-ortho-cresyl phosphate (TOCP) (750 mg/kg body weight, p.o.) or were pretreated with progesterone (2 mg/kg body weight/day, i.p.) prior to TOCP exposure. The results showed that TOCP exposure induced typical OPIDN signs in hens and caused demyelinating lesions in the sciatic nerves. The pretreatment of progesterone delayed and reduced TOCP-induced gait impairment scores and restored the decreased expression of S-100β in the sciatic nerves of TOCP-exposed hens. Moreover, progesterone alleviated the TOCP-induced demyelination of the sciatic nerves. These effects were accompanied by alterations in the protein levels of the ErbB2/p-Akt signaling pathway. These findings indicate that progesterone effectively attenuates TOCP-induced delayed neurotoxicity and protects against myelin damage. This protective effect may be associated with the suppression of TOCP-induced activation of the ErbB2/p-Akt pathway, accompanied by the restoration of S-100β expression.

Tri-o-cresyl phosphate (TOCP) is widely used as a plasticizer, flame retardant, and lubricant additive, but has been reported to impair spermatogenesis. However, how TOCP affects spermatogenesis remains unclear. Therefore, the objective of this study is to investigate the underlying mechanism by which TOCP disrupts spermatogenesis. In order to achieve this, adult male mice were orally administered TOCP at doses of 0, 200, or 400 mg/kg for two weeks, and we found that TOCP exposure reduced the number of germ cells and decreased sperm density. Moreover, the numbers of PCNA-positive cells and phospho-histone H3 (Ser10)-positive cells in mouse testicular tissues were significantly decreased following TOCP treatment, indicating that germ cell proliferation may be impaired. In addition, TOCP did not affect the protein expression of neuropathy target esterase (NTE) in testicular tissues but markedly inhibited its enzymatic activity (by approximately 30% relative to the control level). In vitro experiments further demonstrate that TOCP suppressed cell proliferation and mitotic progression in mouse GC-1 spg cells and excessively activated endoplasmic reticulum (ER) stress. Treatment with 4-phenylbutyric acid (4-PBA), an ER stress inhibitor, partially reversed the TOCP-induced inhibition of cell proliferation and mitosis. Furthermore, TOCP inhibited NTE activity in GC-1 spg cells, and NTE knockdown produced a phenotype similar to that observed after TOCP exposure, characterized by suppressed cell proliferation and mitotic progression. Surprisingly, ER stress was not activated in GC-1 spg cells following NTE knockdown. Collectively, these findings suggest that TOCP may impair spermatogenesis by inhibiting the proliferation and mitotic progression of mouse germ cells, potentially through mechanisms involving excessive activation of ER stress or suppression of NTE activity.

The production of aroma in aromatic rice is due to the increase of 2-acetyl-1-pyrroline (2-AP) precursor substances caused by the functional deletion of Badh2 gene on chromosome 8, and the accumulation of 2AP makes rice produce aroma. In this study, Badh2 gene was isolated and cloned from 18 representative aromatic rice cultivars in Southern Henan, and the bioinformatics analysis of Badh2 gene was carried out. Meanwhile, seven functional molecular markers developed by Badh2 gene were used to detect and analyze Badh2 gene in 18 aromatic rice varieties from Southern Henan. The results showed that the coding region of Badh2 gene was 1509 bp in length. It contained 15 exons and 14 introns, and encoded 503 amino acids. There are many types of variation of the Badh2 gene in the 18 aromatic rice varieties. According to the variation of Badh2 gene, the tested aromatic rice varieties could be divided into three groups, among which Xinxianggeng 1, Xiangnuo 25, Heixiangdao 193 and Xiangbao 2 were concentrated in group Ⅰ, while the other 14 kinds of aromatic rice were concentrated in group II. Seven functional molecular markers of Badh2 gene were used to detect different varieties mutation types in exon 2, exon 4~5, exon 7 and exon 13 of Badh2 gene. No aromatic rice varieties with different mutation types were found in promoter region, exon 12 and exon 14 of Badh2 gene. Therefore, our results provide important information for understanding the genetic basis of fragrant genes in aromatic rice germplasm resources in Southern Henan and breeding new varieties of high-quality aromatic rice using molecular marker-assisted selection.