Effects of Lactobacillus plantarum (L) and molasses (M) on nutrient composition, aerobic stability, and microflora of alfalfa silage in sandy grasslands.

The objective of this experiment was to investigate the effects of Lactobacillus plantarum and molasses on the nutrient composition, fermentation quality, bacterial count, aerobic stability, and microflora of alfalfa silage in sandy grasslands. The experimental treatments included control (CK), 106 CFU/g Lactobacillus plantarum (L), 5% molasses (M), and 106 CFU/g Lactobacillus plantarum + 5% molasses (LM). The nutrient composition, fermentation quality, bacterial count, aerobic stability, and microflora were determined after 14 days and 56 days of ensiling, respectively. The results showed that the addition of L, M, and LM reduced dry matter loss (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) content, and increased water-soluble carbohydrates (WSC) and ether extract (EE) content, compared to the CK group. Meanwhile, more lactic acid (LA) and accelerated fermentation were observed, causing the pH value to drop below 4.5 in the L, M, and LM groups after 56 days of ensiling. The addition of L, M, and LM promoted lactic acid bacteria (LAB), and inhibited yeast. The addition of L significantly increased the content of acetic acid (AA). In terms of microflora, the addition of L, M, and LM made Firmicutes become the dominant bacterial phylum earlier, while Lactobacillus, Weissella, and Pediococcus had a higher abundance. According to the result of Pearson's correlation, there is a very significant negative correlation between pH value and Lactobacillus (P < 0.01) and a very significant positive correlation between pH value and Lactococcus, Enterobacter, Enterococcus, and Leuconostoc (P < 0.01), which may be inhibited by Lactobacillus under the decreased pH value. The results of the prediction of microbial genes indicated that the addition of M could enhance the carbohydrate metabolism and membrane transport metabolism, which may contribute to LA production by LAB metabolism. In general, L, M and LM all improved the fermentation quality and reduced the loss of nutrients to varying degrees, but considering the fermentation quality, the overall effects of M and LM were better than L. M and LM are recommended to be used as silage additives in the process of alfalfa silage in sandy grasslands to improve the quality.

Effects of organic trace minerals chelated with oligosaccharides on growth performance, blood parameters, slaughter performance and meat quality in sheep.

The present study assessed the effects of oligosaccharide-chelated organic trace minerals (OTM) on the growth performance, digestive enzyme activity, blood parameters, slaughter performance, and meat quality indexes of mutton sheep. A total of 60 East Ujumuqin × small-tailed Han crossbred mutton sheep were assigned to two groups (10 duplicates per group) by body weight (26.12 ± 3.22 kg) according to a completely randomized design. Compared to the CON group, the results of the OTM group showed: (1) no significant changes in the initial body weight, final body weight, dry matter intake, average daily gain, and feed conversion ratio (p > 0.05); (2) the activities of trypsin, lipase, and amylase in the jejunum were significantly increased (p < 0.05); (3) serum total protein, albumin, and globulin of the blood were significantly increased (p < 0.05), and the growth factor interleukin IL-10 was significantly higher (p < 0.05), while IL-2, IL-6, and γ-interferon were significantly lower (p < 0.05). Immunoglobulins A, M, and G were significantly higher (p < 0.05); (4) the live weight before slaughter, carcass weights, dressing percentage, eye muscle areas, and GR values did not differ significantly (p > 0.05); (5) shear force of mutton was significantly lower (p < 0.05), while the pH45min, pH24h, drip loss, and cooking loss did not show a significant difference (p > 0.05). The content of crude protein was significantly higher (p < 0.05), while the ether extract content was significantly reduced (p < 0.05), but no significant difference was detected between moisture and ash content; (6) the total amino acids, essential amino acids, semi-essential amino acids, and umami amino acids were significantly increased (p < 0.05). Although umami amino acids were not significant, the total volume increased (p > 0.05). Among these, the essential amino acids, threonine, valine, leucine, lysine in essential amino acids and arginine were significantly increased (p < 0.05). Also, non-essential amino acids, glycine, serine, proline, tyrosine, cysteine, and aspartic acid, were significantly higher (p < 0.05). The content of alanine, aspartate, glutamic acid, phenylalanine, and tyrosine in umami amino acids was significantly higher (p < 0.05).

Effects of guanidinoacetic acid on in vitro rumen fermentation and microflora structure and predicted gene function.

The fermentation substrate was supplemented with 0% guanidinoacetic acid (GAA) (control group, CON), 0.2% GAA (GAA02), 0.4% GAA (GAA04), 0.6% GAA (GAA06) and 0.8% GAA (GAA08) for 48 h of in vitro fermentation. Gas production was recorded at 2, 4, 6, 8, 12, 24, 36, and 48 h of fermentation. The gas was collected, and the proportions (%, v/v) of H2, CH4 and CO2 were determined. The rumen fermentation parameters, including pH, ammonia nitrogen (NH3-N), microbial protein (MCP) and volatile fatty acids (VFAs), were also determined. Furthermore, the bacterial community structure was analyzed through 16S rRNA high-throughput sequencing. The gene functions were predicted using PICRUSt1 according to the Kyoto Encyclopedia of Genes and Genomes (KEGG). The results showed that with the increase in GAA supplementation levels, the MCP and the concentration of rumen propionate were significantly increased, while the concentration of isovalerate was significantly decreased (p < 0.05). The results of microbial diversity and composition showed that the Shannon index was significantly decreased by supplementation with GAA at different levels (p < 0.05), but the relative abundance of norank_f_F082 and Papillibacter in the GAA06 group was significantly increased (p < 0.05). Especially in group GAA08, the relative abundances of Bacteroidota, Prevotella and Prevotellaceae_UCG-001 were significantly increased (p < 0.05). The results of gene function prediction showed that the relative abundances of the functions of flagellar assembly, bacterial chemotaxis, plant-pathogen interaction, mismatch repair and nucleotide excision repair were significantly decreased (p < 0.05), but the relative abundances of bile secretion and protein digestion and absorption were significantly increased (p < 0.05). In conclusion, supplementation with 0.8% GAA enhanced in vitro rumen fermentation parameters, increased the relative abundance of Prevotella and Prevotellaceae_UCG-001 in the rumen, and increased the metabolic pathways of bile secretion and protein digestion and absorption.

Portulaca oleracea L. Extract Alleviated Type 2 Diabetes Via Modulating the Gut Microbiota and Serum Branched-Chain Amino Acid Metabolism.

SCOPE: Portulaca oleracea L. extracts (PE) show hypoglycemic function, but the precise mechanism remains obscure. This study is designed to investigate the association of the antidiabetes effect of PE with the gut microbiota modulation and BCAAs metabolism. METHODS AND RESULTS: The Orbitrap LC-MS to Orbitrap Fusion Lumos Tribrid mass spectrometer is employed to analyze the major compounds in PE. The components of the intestinal microflora in diet-induced/STZ-treated diabetic mice are analyzed by high-throughput 16S rRNA genes sequencing. The results show that PE improves blood glucose and insulin level, increases anti-inflammatory cytokine level, lowers serum branched-chain amino acids (BCAAs), and increases serum glutamine level. PE also protects the mucosal epithelium of the colon and cecum from damage. On the impact of gut microbial composition, PE reduces the Firmicutes to Bacteroidetes ratio and the abundance of the Lachnospiraceae_NK4A136_group, Blautia, Ruminiclostridium_9, Dubosiella, and increases the abundance of the Bacteroides, Akkermansia, and Mucisprillum genera. Bacterial functionality prediction indicates PE potentially inhibits bacterial BCAAs biosynthesis, and promotes the tissue-specific expression of BCAAs catabolic enzyme for reducing BCAAs supplementation. CONCLUSION: These results reveal that PE improving T2D-related biochemical abnormalities is associated not only with gut microbiota modification but also with the tissue-specific expression of BCAAs catabolic enzyme.

A Multifunctional Magnetic Red Blood Cell-Mimetic Micromotor for Drug Delivery and Image-Guided Therapy.

Inspired by nature, innovative devices have been made to imitate the morphology and functions of natural red blood cells (RBCs). Here, we report a red blood cell-mimetic micromotor (RBCM), which was fabricated based on a layer-by-layer assembly method and precisely controlled by an external rotating uniform magnetic field. The main framework of the RBCM was constructed by the natural protein zein and finally camouflaged with the RBC membrane. Functional cargos such as Fe3O4 nanoparticles and the chemotherapeutic agent doxorubicin were loaded within the wall part of the RBCM for tumor therapy. Due to the massive loading of Fe3O4 nanoparticles, the RBCM can be precisely navigated by an external rotating uniform magnetic field and be used as a magnetic resonance imaging contrast agent for tumor imaging. The RBCM has been proven to be biocompatible, biodegradable, magnetically manipulated, and imageable, which are key requisites to take micromotors from the chalkboard to clinics. We expect the RBC-inspired biohybrid device to achieve wide potential applications.

Novel carrier-free, charge-reversal and DNA-affinity nanodrugs for synergistic cascade cancer chemo-chemodynamic therapy.

The combination of chemotherapy (CT) and chemodynamic therapy (CDT) is an emerging therapeutic strategy for tumors; however, its therapeutic efficacy is usually impaired by the shortage of high-efficiency intracellular catalysts for CDT and the poor tumor selectivity of CT. To address this concern, novel carrier-free nanodrugs (CMC-DD2) self-assembled from the natural melanin complex (CMC) with a superior CDT performance, and dehydroabietic acid hexamer (DD2) displaying a potent antitumor activity were proposed for the synergistic combination of CT and CDT. CMC-DD2 preferred to enter tumor cells and localize in the nucleus after lysosome escape due to its pH-dependent charge-reversal properties. Nanodrugs internalized by the nucleus directly bound the DNA and altered its conformation. Then, the dissociation of CMC-DD2 was efficiently triggered by intracellular hydrogen peroxide (H2O2) with the release of DNA damaging agents, including nitrate anions, hydroxyl radicals (●OH) and DD2. Finally, severe DNA damage induced mitochondrial apoptosis in HepG2 cells. An in vivo assessment further demonstrated the superior tumor selectivity and suppressor capacity and no/low toxicity of the nanodrugs. Overall, novel carrier-free, charge-reversal, nucleus-targeting, biodegradable, and DNA-affinity nanodrugs represent safe and effective platforms for the combination of CT and CDT.

A novel melanin complex displayed the affinity to HepG2 cell membrane and nucleus.

Chitosan-melanin complex from Catharsius molossus L. has proven to possess superior pharmaceutical excipient performance and may be the new source of water-soluble protein-free natural melanin. Herein, it was enzymatically hydrolyzed into the chitooligosaccharide-melanin complex (CMC) whose main chemical units were composed of eumelanin and chitooligosaccharides and showed three-layer structures. Additionally, this biomacromolecule could self-assemble into 40 nm nanoparticles (CMC Nps) in a weakly acidic aqueous solution. Interestingly, CMC displayed strong affinity for cell membrane by binding the phosphatidylserine, glycoprotein, glycolipids and glycosaminoglycans accumulated on the surface of tumor cells, notably, CMC Nps could enter cells and mainly target the nucleus by interacting with DNA and/or RNA substrates located around the nucleus to disrupt the proliferation and apoptosis processes. The findings suggest CMC may be the novel material for subcellular organelle targeting of cancer cells.