Exploring the characteristics of Burkholderia gladioli pathovar cocovenenans: Growth, bongkrekic acid production, and potential risks of food contamination in wet rice noodles and vermicelli.

This research investigated the presence of Burkholderia gladioli pathovar cocovenenans (BGC) in wet rice and starch products, Tremella, and Auricularia auricula in Guangzhou, China. It examined BGC growth and bongkrekic acid (BA) production in wet rice noodles and vermicelli with varying rice flour, edible starch ratios, and oil concentrations. A qualitative analysis of 482 samples revealed a detection rate of 0.62%, with three positive for BGC. Rice flour-based wet rice noodles had BA concentrations of 13.67 ± 0.64 mg/kg, 2.92 times higher than 100% corn starch samples (4.68 ± 0.54 mg/kg). Wet rice noodles with 4% soybean oil had a BA concentration of 31.72 ± 9.41 mg/kg, 5.74 times higher than those without soybean oil (5.53 ± 1.23 mg/kg). The BA concentration correlated positively (r = 0.707, P < 0.05) with BGC contamination levels. Low temperatures (4 °C and -18 °C) inhibited BGC growth and BA production, while higher storage temperatures (26 °C and 32 °C) promoted BGC proliferation and increased BA production. Reducing edible oil use and increasing edible starch can mitigate the risk of BGC-related food poisoning in wet rice noodles and vermicelli production. Further research is needed to find alternative oils that do not enhance BA production. Strengthening prevention and control measures is crucial across the entire production chain to address BGC contamination and BA production.

Flammulina velutipes Mycorrhizae Attenuate High Fat Diet-Induced Lipid Disorder, Oxidative Stress and Inflammation in the Liver and Perirenal Adipose Tissue of Mice.

Flammulina velutipes (FV) is edible mushroom that has nutritional and medicinal values. FV mycorrhizae, the by-products of FV, are an abundant source and receive less attention. The objective of this study was to investigate the composition of FV mycorrhizae, and its effects on high fat diet (HFD)-induced lipid disorder, oxidative stress, and inflammatory cytokines, both in the liver and perirenal adipose tissue (PAT) of mice. The results showed that FV mycorrhizae contain abundant trace elements, polysaccharide, amino acids and derivatives, and organic compounds. It was found that 4% FV mycorrhizae (HFDFV) supplementation decreased HFD-induced liver weight and triglyceride (TG) in the plasma, liver and PAT, altered plasma and hepatic fatty acids profiles, promoted gene expression involved in lipid hydrolysis, fatty acid transportation and ß-oxidation in the liver and reduced lipid synthesis in the liver and PAT. HFDFV attenuated HFD-induced oxidative stress and pro-inflammatory cytokine by increasing GSH/GSSG, and decreasing levels of MDA and IL6 both in the liver and PAT, while it differentially regulated gene expression of IL1ß, IL6, and CCL2 in liver and PAT. The results indicated that FV mycorrhizae are effective to attenuate HFD-induced lipid disorder, oxidative stress and inflammation in the liver and PAT, indicating their promising constituents for functional foods and herbal medicine.

A versatile luminescent resonance energy transfer (LRET)-based ratiometric upconversion nanoprobe for intracellular miRNA biosensing.

Rational design and fabrication of bio-nanoprobes for intracellular miRNA biosensing are highly desired for early clinical diagnosis and prognosis. Herein, we have developed a versatile LRET-based ratiometric (LBRU) nanoprobe of NaYF4:Yb,Er@NaYF4@NH2-mSiO2/rhodamine B/C-DNA sandwich-structured nanocomposites for intracellular miRNA biosensing. The nanoprobe was composed of NaYF4:Yb,Er@NaYF4 upconversion nanoparticles (energy donor) with an amino functionalized mesoporous silica shell (NH2-mSiO2), rhodamine B (acceptor) loaded into the mesopores of NH2-mSiO2, and the complementary sequences of target miRNA (denoted as C-DNA) acting as recognition species wrapped on the nanocomposite. Due to the LRET behavior between donors and acceptors, the loaded rhodamine B can quench the green upconversion emission of NaYF4:Yb,Er@NaYF4 at 540 nm completely. Moreover, it can be released from the nanocomposite in the presence of target miRNA, which blocked the LRET behavior to "turn on" the green upconversion luminescence. Besides, as the unaffected red upconversion luminescence (at 660 nm) can be used as an internal standard to provide built-in correction for environmental effects, the intensity ratio of upconversion luminescence at 540 and 660 nm (I540/I660) was employed as the output signal to afford an accurate detection of target miRNA. Due to the biocompatibility, high photostability and low auto-fluorescence background, the nanoprobe was successfully utilized to diagnose the intracellular miRNA-21 expression in MCF-7 cells via upconversion fluorescence imaging. We envision that the proposed LBRU nanoprobe has great potential applications in early cancer diagnosis.

Comparison of the effects of resveratrol and its derivative pterostilbene on hepatic oxidative stress and mitochondrial dysfunction in piglets challenged with diquat.

This study investigated the potential of resveratrol (RSV) and its derivative pterostilbene (PT) to prevent diquat (DQ)-induced hepatic oxidative damage and mitochondrial dysfunction in piglets. Seventy-two weanling piglets were randomly divided into the following treatment groups: non-challenged control group, DQ-challenged control group, and DQ-challenged groups supplemented with either 300 mg RSV per kg of diet or an equivalent amount of PT. Each treatment group consisted of six replicates with three piglets per replicate (n = 6). After a two-week feeding trial, piglets were intraperitoneally injected with either 10 mg DQ per kg of body weight or sterile saline. At 24 hours post-injection, one piglet from each replicate (six piglets per treatment) was randomly selected for sample collection and biochemical analysis. Compared with the DQ-challenged control group, PT attenuated the growth loss of piglets after the DQ challenge (P < 0.05). Administration of PT was more effective than its parent compound in inhibiting the DQ-induced hepatic apoptosis and the increased generation of total cholesterol, superoxide anion, and lipid peroxidation products (P < 0.05). Specifically, PT facilitated nuclear factor erythroid 2-related factor 2 signals and the expression and activity of manganese superoxide dismutase, while it also prevented mitochondrial swelling, membrane potential collapse, and adenosine triphosphate depletion, possibly through the activation of sirtuin 1 (P < 0.05). These results indicate that PT may be superior to RSV as an antioxidant to protect the liver of young piglets from oxidative insults.

Berberine improved intestinal barrier function by modulating the intestinal microbiota in blunt snout bream (Megalobrama amblycephala) under dietary high-fat and high-carbohydrate stress.

The study investigated whether dietary berberine supplementation could improve intestinal barrier against inflammation induced by high-fat and high-carbohydrate diets in blunt snout bream. Fish (average initial weight 44.83 ± 0.06 g) were fed with six kinds of diets (control, high-fat diet (10% lipid) and high-carbohydrate (43% nitrogen-free extract) diet, control/berberine, high-fat/berberine or high-carbohydrate/berberine) for 8 weeks, respectively. Feeding mode of berberine (50 mg/kg diet) was adopted to two-week interval. After feeding trial, fish growth performance and intestinal barrier function were estimated. The result showed that no significant interactions between diet and berberine in growth performance, whole body composition or protein utilization were observed (P > 0.05). Specific growth rate (SGR) and feed conversion ratio (FCR) were significantly affected by berberine (P < 0.05). Protein efficiency ratio (PER), nitrogen retention (NRE), fish whole-body lipid contents increased greatly in high-fat or high-carbohydrate diets (P < 0.05). Significant interactions between diet and berberine were observed in fish intestinal barrier (physical, chemical, immunological and microbiological barriers) (P < 0.05). High-fat and high-carbohydrate diets could increase significantly intestinal permeability and inflammatory response, decrease intestinal mucins gene expression levels, and make the intestinal microbiota out of balance (P < 0.05). Berberine significantly inhibited inflammation response and modulated intestinal microflora profile (P < 0.05). Taken together, berberine could alleviate intestinal barrier damage injured by high-fat or high-carbohydrate diet and improve the growth performance of blunt snout bream.

Effects of n-acetyl-cysteine supplementation in late gestational diet on maternal-placental redox status, placental NLRP3 inflammasome, and fecal microbiota in sows1.

Although n-acetyl-cysteine (NAC) has been shown to efficiently alleviate oxidative stress, inflammatory response, and alter gut microbiota, little attention has been focused on their interactions with placental metabolic status of sows. The effects of NAC on the placental redox status, function, inflammasome, and fecal microbiota in sows were explored to clarify the correlation between the fecal microbiota and placenta. Sows were divided into either the control group or the NAC group which received dietary 0.5% NAC supplementation from day 85 of gestation to delivery. Plasma redox status, placental growth factors, nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) inflammasome, fecal microbial metabolites, and communities were evaluated. Compared with the control group, although NAC did not ameliorate reproductive performance of sows (P > 0.05), it significantly improved maternal-placental health, which was accompanied by increased activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD), decreased level of malondialdehyde (MDA), and lowered expression of interleukin (IL)-1ß and IL-18 through inhibiting NLRP3 inflammasome (P < 0.05). Additionally, NAC significantly increased placental insulin-like growth factors (IGFs) and E-cadherin contents (P < 0.05), elevated the expression of genes involved in angiogenesis and amino acids transporters (P < 0.05), and decreased the microtubule-associated protein light chain 3B (LC3B) and Beclin-1 protein expression (P < 0.05). Furthermore, NAC increased the relative abundances of fecal Prevotella, Clostridium cluster XIVa, and Roseburial/Eubacterium rectale (P < 0.05), which were negatively correlated with placental NLRP3 and positively with solute carrier family 7, member 8 (Slc7a8; P < 0.05). In conclusion, NAC supplementation during late gestation alleviated maternal-placental oxidative stress and inflammatory response, improved placental function, and altered fecal microbial communities.

Regulation of an antioxidant blend on intestinal redox status and major microbiota in early weaned piglets.

OBJECTIVE: According to the "antioxidants network" theory, the present study was conducted to evaluate the regulation of an antioxidant blend on intestinal redox status and major microbiota of early-weaned piglets. METHODS: Piglets from 15 litters were randomly allocated by litter to the control group (suckling normally, fed the basal diet, n = 5), the weaning group (weaned at age 21 d, fed the basal diet, n = 5), and the repair group (weaned at age 21 d, fed the basal diet supplemented with an antioxidant blend, n = 5). The redox status and major microbiota in jejunum and colon tracts of 24-d-old piglets were detected, respectively. RESULTS: Early weaning resulted in significant decreases in jejunum and colon antioxidant capacities, Lactobacillus and Bifidobacterium counts, and significant increases in levels of jejunum malondialdehyde, colon hydroxyl radicals, jejunum and colon H2O2, and Escherichia coli counts in piglets. The observed imbalance of the intestinal redox status and microbiota was significantly restored by the antioxidant blend. Interestingly, intestinal selected antioxidative items presented a positive correlation with potential beneficial bacteria and a negative correlation with E. coli. Nevertheless, selected oxidative items and the bacteria presented an inverse relationship in piglets. CONCLUSION: Supplementation of the antioxidant blend effectively restored intestinal redox status and microbiota balance in the porcine intestine in response to early weaning stress, enhancing intestinal health and function of piglets.

Effect of N-acetyl cysteine on enterocyte apoptosis and intracellular signalling pathways' response to oxidative stress in weaned piglets.

N-Acetyl cysteine (NAC) has been widely used for preventing reactive oxygen species-induced damage. However, little is known as to whether dietary NAC supplementation would alleviate intestinal injury in weaned piglets. The present study evaluated the effect of NAC on enterocyte apoptosis and intracellular signalling pathways' response to weaning stress. The control piglets were normally suckling, and piglets in the weaning and NAC groups were fed the basal diet and basal+NAC diet from 14 to 25 d of age, respectively. Compared with the control piglets, weaning increased cortisol concentrations (P< 0·05), decreased superoxide dismutase and glutathione peroxidase activities (P< 0·05), increased malondialdehyde content (P< 0·05) in serum and enhanced enterocyte apoptosis index (AI) and concentrations of caspase-3, caspase-8 and caspase-9 (P< 0·05). Gene expression analyses indicated that weaning induced apoptosis via Fas signalling and mitochondrial pathways in weaned piglets. Dietary NAC supplementation decreased (P< 0·05) cortisol concentrations and the AI, increased (P< 0·05) antioxidant status in serum and alleviated histopathological changes in the intestine. It also inhibited Fas, caspase-3, caspase-8 and integrin αvß6 (αvß6) gene expressions in the NAC-treated piglets. However, no significant decrease (P>0·10) in caspase-3, caspase-8 and caspase-9 concentrations was observed in the NAC group compared with the weaning group. In conclusion, weaning may induce enterocyte apoptosis via the activation of Fas-dependent and mitochondria-dependent apoptosis. Although NAC had no effect on caspase concentrations, it was clearly beneficial for preserving morphological integrity in weaned piglets via the regulation of cell apoptosis and the inhibition of Fas-dependent apoptosis and αvß6 expression.

[Effects of vitamin E and selenium on the metabolism of free radicals in broilers].

Taking 200 healthy broilers at 14 d of age as test materials, the free radicals in their blood and tissues were detected by electron spin resonance (ESR) and biochemical methods, aimed to investigate the effects of vitamin E (V(E)) and selenium (Se) on the metabolism of different free radicals and their dynamic changes in the broilers. The results showed that the content of NO free radicals in broilers tissues decreased with increasing supplementing level of V(E), while high supplementation of Se tended to induce the production of NO free radicals. High supplementation of V(E) and Se in feeds improved the GSH-Px and SOD activities in broilers serum and liver significantly. With the extension of experimental period, the SOD activity in tissues decreased, while GSH-PX activity increased gradually, implying that the deficiency of V(E) and/or Se might induce the overproduction of O2*- and H2O2 free radicals. H2O2 free radicals might be produced largely at early stage of V(E) and Se deficiency and declined then, while the over-production of O2*- free radicals could maintain for a long time. The deficiency of V(E) and/or Se could improve the MDA content significantly, and Se deficiency had higher effects than V(E) deficiency. There were synergic effects in the metabolism of NO, O2 and H2O2 free radicals.