Prediction models for monitoring selenium and its associated heavy-metal accumulation in four kinds of agro-foods in seleniferous area.

Se-rich agro-foods are effective Se supplements for Se-deficient people, but the associated metals have potential risks to human health. Factors affecting the accumulation of Se and its associated metals in Se-rich agro-foods were obscure, and the prediction models for the accumulation of Se and its associated metals have not been established. In this study, 661 samples of Se-rich rice, garlic, black fungus, and eggs, four typical Se-rich agro-foods in China, and soil, matrix, feed, irrigation, and feeding water were collected and analyzed. The major associated metal for Se-rich rice and garlic was Cd, and that for Se-rich black fungus and egg was Cr. Se and its associated metal contents in Se-rich agro-foods were positively correlated with Se and metal contents in soil, matrix, feed, and matrix organic contents. The Se and Cd contents in Se-rich rice grain and garlic were positively and negatively correlated with soil pH, respectively. Eight models for predicting the content of Se and its main associated metals in Se-rich rice, garlic, black fungus, and eggs were established by multiple linear regression. The accuracy of the constructed models was further validated with blind samples. In summary, this study revealed the main associated metals, factors, and prediction models for Se and metal accumulation in four kinds of Se-rich agro-foods, thus helpful in producing high-quality and healthy Se-rich.

Transcriptome analysis provides new insight into the distribution and transport of selenium and its associated metals in selenium-rich rice.

Selenium is an essential trace element for humans and obtained from diary diets. The consumption of selenium-rich agricultural food is an efficient way to obtain selenium, but the quality and safety of selenium-rich agro-food are always affected by their associated heavy metals, even poses a potential threaten to human health. In this research, a sampling survey of heavy metals contents in selenium-rich rice was conducted, 182 sets of selenium-rich rice samples were collected from five selenium-rich rice-producing areas of China, and the accumulation of selenium and cadmium were found to be associated in rice and soil. Subsequently, a pot experiment was performed in the greenhouse via treating the soil samples with 12 different concentrations of selenium and heavy metals, and the contents of selenium and cadmium in rice grain were confirmed to be significantly associated. Moreover, transcriptome analysis revealed that the up-regulation of transporter-coding may promote the absorption of selenium and cadmium. The expression of antioxidant-coding genes and cadmium chelator transporter coding-genes was up-regulated to reduce the toxicity of cadmium. Meanwhile, the up-regulation of key genes of the ascorbic acid-glutathione metabolic pathway were responsible for the association between selenium and cadmium in Se-rich rice. Our work suggested the correlation between selenium and cadmium accumulation in selenium-rich rice, clarified their accumulation mechanism, provides a direction for the scientific production of selenium-rich agro-foods.

Effects of preheating and drying methods on pyridoxine, phenolic compounds, ginkgolic acids, and antioxidant capacity of Ginkgo biloba nuts.

Although ginkgo nuts are very nutritious and loaded with numerous bioactive compounds, the nuts contain significant levels of unwanted compounds (ginkolic acids) which are toxic to consumption. To reduce or eliminate these toxic compounds without impacting the nutritional value and the bioactivity of the final product, an appropriate processing technology is needed. Thus, the effect of preheating (90 and 120°C) prior to drying (freeze drying: FD, hot air drying: HAD, and HAD in tandem with FD: HAD-FD) was evaluated on ginkgolic acids, pyridoxine analogues, phenolic compounds, and antioxidant properties of ginkgo nuts. Our results pointed out a significant decrease (below 50%) of ginkgolic acids in ginkgo nuts samples processed at 90°C compared to the control. The major compounds found after treatments were respectively, kaempferol (36.66-354.38 µg/g), quercetin (9.04-183.71 µg/g), and caffeic acid (19.66-106.88 µg/g). Principal component analysis (PCA) revealed that preheating at 90°C prior to HAD-FD would be a proper and reasonable approach for preserving the bioactive compounds and antioxidant capacity of ginkgo nuts (EC50 ranged from 2.25 to 4.60 mg/mL) while significantly reducing their content in toxic compounds.

Benefit-risk assessment of dietary selenium and its associated metals intake in China (2017-2019): Is current selenium-rich agro-food safe enough?

Dietary consumption of selenium-rich agro-food is an effective way to avoid selenium deficiency diseases, however, over consumption of selenium-rich agro-food will result in potential risk of selenosis and problems with associated metals. In this study, we measured the concentrations of selenium and its associated metals in 2756 common and 4894 selenium-rich agro-food samples in 10 regions of China. We found that selenium-rich rice, flour, edible fungi and algae, meat, and tea contain higher levels of associated metals than other selenium-rich agro-food samples. Increasing the consumption of selenium-rich agro-food could make the actual intakes (AIs) of selenium for all population to meet respective recommended daily intakes (RDIs). Benefit-risk assessment results indicated that increasing the consumption of selenium-rich agro-food make AIs of selenium for all populations meet RDIs, chromium intakes for people under 18 years old exceed provisional tolerated daily intake (PTDIs), while arsenic and cadmium intakes are close to PTDIs. The main dietary contributors of selenium, chromium, arsenic and cadmium were meat, edible fungi and algae, rice, and rice, respectively. The study supported the consumption of selenium-rich agro-food for effective selenium supplement, but also emphasized potential risk from associated metals in selenium-rich agro-food, especially chromium.

Determination of Selenium in Common and Selenium-Rich Rice from Different Areas in China and Assessment of Their Dietary Intake.

In this study, 41 common rice varieties and 211 selenium-rich rice varieties from ten representative areas in China were collected in 2017-2019. The selenium contents of rice were analyzed with optimized inductively coupled plasma mass spectrometry (ICP-MS). Selenium concentrations of common rice and selenium-rich rice ranges were 0.81-7.26 and 0.76-180.73 µg/100 g, respectively. The selenium contents in selenium-rich rice from different areas were significantly different (p < 0.001) while those in common rice from different areas were not. The selenium-rich rice in Harbin and Keshan showed the lowest selenium level and those from selenium-rich areas (Enshi and Ankang) were highest. Based on the estimation of the risk assessment software @risk7.0 (Palisade Corporation, New York, NY, USA), the consumption of selenium-rich rice can effectively increase dietary selenium intake for the population. However, the risk index of P95 (Percentile 95) selenium exposure at the tolerable upper intake level for children at 2-14 years old exceeded 100%, with potential risk currently. Therefore, the consumption of selenium-rich rice should be properly monitored for young children and adolescents.

Bactrian camel nanobody-based immunoassay for specific and sensitive detection of Cry1Fa toxin.

The variable domain of the heavy-chain-only antibody (VHH) or nanobody (Nb), derived from camelids, begins to play an important role on the detection of protein markers. In this study, we constructed a phage-displayed library of VHHs against Cry1Fa by immunizing a healthy Bactrian camel with Cry1Fa toxin. After a series of bio-panning and screening by phage display technology, three anti-Cry1Fa nanobodies (Nbs) with great difference in complementarity determining region 3 (CDR3) were obtained and they were highly specific to Cry1Fa as well as showed full of activity when exposed to 70 °C for 3 h. Through modifying Nbs with Horseradish Peroxidase (HRP) and biotin, two Nbs which can recognize the different epitopes of Cry1Fa were determined and they were used to establish a novel sandwich immune ELISA based on biotin-SA interaction for Cry1Fa detection. The immunoassay exhibited a linear range from 1 to 100 ng/mL with a detection limit of 0.88 ng/mL. The recoveries from spiked corn and soybean samples were ranged from 83.33 to 117.17%, with a coefficient of variation (C.V) less than 6.0%. All together, the proposed immunoassay will be a promising way for sensitive and accurate determination of Cry1Fa toxin.

Treatment with ginseng total saponins improves the neurorestoration of rat after traumatic brain injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Ginseng, the root of Panax ginseng C.A. Meyer, is a traditional medicinal herb that has been widely used in Asia for the treatment of many diseases through its effects of reinforcing vitality, strengthening the bodily resistance to pathogenic factors, engendering body liquids and allaying thirst, relieving uneasiness of the body and mind and benefiting intelligence, reducing body weight and prolonging life. Ginsenosides are the most important biologically active substances in ginseng. Many reports have suggested that ginsenosides could exert prominent neuroprotective and neurotrophic effects, promote neural stem/progenitor cell (NSC) proliferation and promote neurite outgrowth and neuronal network formation. The present study aimed to investigate whether treatment with ginsenosides could facilitate NSC proliferation in the hippocampal formation after traumatic brain injury (TBI) and contribute to the recovery of neurological functions including learning and memory. MATERIALS AND METHODS: The modified Feeney׳s method was used to induce a TBI in rats. Ginseng total saponins (GTS) were treated intraperitoneally twice a day for 1 week after the TBI. The neurological functions, morphology of the hippocampus, expression of nerve growth-related factors and number of NSCs in the hippocampal formation ipsilateral to the trauma were determined. RESULTS: We determined 1) GTS (5-80 mg/kg) treatment after a TBI improved the recovery of neurological functions, including learning and memory, and reduced cell loss in the hippocampal area. The effects of GTS at 20, 40, 60, and 80 mg/kg were better than the effects of GTS at 5 and 10 mg/kg. 2) GTS treatment (20 mg/kg) after a TBI increased the expression of NGF, GDNF and NCAM, inhibited the expression of Nogo-A, Nogo-B, TN-C, and increased the number of BrdU/nestin positive NSCs in the hippocampal formation. CONCLUSIONS: GTS treatment in rats after a TBI alleviated the secondary brain injury and ameliorated the neurological functions with an effective dose limit of 5-80 mg/kg. GTS regulated the expression of nerve growth-related factors and improved the proliferation of neural stem/progenitor cells, which might facilitate neural regeneration and tissue repair, and might contribute to the recovery of neurological functions, including learning and memory. These effects of GTS might provide a foundation for the use of ginseng as a medicinal herb to enhance intelligence, reduce the aging process and prolong life in the traditional medicine.

Profiling polyphenols of two diploid strawberry (Fragaria vesca) inbred lines using UHPLC-HRMS(n.).

Phenolic compounds in the fruits of two diploid strawberries (Fragaria vesca f. semperflorens) inbred lines-Ruegen F7-4 (a red-fruited genotype) and YW5AF7 (a yellow-fruited genotype) were characterised using ultra-high-performance liquid chromatography coupled with tandem high-resolution mass spectrometry (UHPLC-HRMS(n)). The changes of anthocyanin composition during fruit development and between Ruegen F7-4 and YW5AF7 were studied. About 67 phenolic compounds, including taxifolin 3-O-arabinoside, glycosides of quercetin, kaempferol, cyanidin, pelargonidin, peonidin, ellagic acid derivatives, and other flavonols were identified in these two inbred lines. Compared to the regular octoploid strawberry, unique phenolic compounds were found in F. vesca fruits, such as taxifolin 3-O-arabinoside (both) and peonidin 3-O-malonylglucoside (Ruegen F7-4). The results provide the basis for comparative analysis of polyphenolic compounds in yellow and red diploid strawberries, as well as with the cultivated octoploid strawberries.