Phytohormones comprise a variety of trace bioactive compounds that can stimulate cell growth and promote metabolic shifts. In the present work, a two-stage screening strategy was innovatively established to identify positive phytohormones for enhancement of astaxanthin and lipid coproduction in microplate-based cultures of mixotrophic Chromochloris zofingiensis. The results showed that auxins were the most efficient stimulators for astaxanthin accumulation. The maximum content of 13.1 mg/g and yield of 89.9 mg/L were obtained using indole propionic acid (10 mg/L) and indoleacetic acid (7.8 mg/L), representing the highest levels of astaxanthin in this microalga reported to date. Total lipids with the highest content (64.5% DW) and productivity (445.7 mg/L/d) were coproduced with astaxanthin using indoleacetic acid. Statistical analysis revealed close relations between phytohormones and astaxanthin and lipid biosynthesis. This study provides a novel original strategy for improving astaxanthin and lipid coproduction in C. zofingiensis using the selected phytohormones as positive stimulators.
Microalgal lipid production by Chlorella protothecoides using sugarcane bagasse hydrolysate was investigated in this study. First, maximum glucose and reducing sugar concentrations of 15.2 and 27.0 g/L were obtained in sugarcane bagasse hydrolysate (SCBH), and the effects of different percentages of glucose and xylose on algal cultivation were investigated. Afterwards, SCBH was used as a carbon source for the cultivation of C. protothecoides and higher biomass concentration of 10.7 g/L was achieved. Additionally, a large amount of fatty acids, accounting up to 16.8% of dry weight, were accumulated in C. protothecoides in the nitrogen-limited (0.1-1 mmol/L) culture. Although SCBH inhibited fatty acid accumulation to a certain degree and the inhibition was aggravated by nitrogen starvation, SCBH favored microalgal cell growth and fatty acid production. The present study is of significance for the integration of cost-effective feedstocks production for biodiesel with low-cost SCBH as well as environmentally friendly disposal of lignocellulosic wastes.
Helicobacter pylori is a major risk factor for gastritis, gastric ulcers and gastric cancer. Traditional therapy with proton pump inhibitor and antibiotics is regarded as optimal for H. pylori eradication whereas, the eradication rate is unsatisfactory. Studies have reported that cranberry may inhibit H. pylori adhesion to the human gastric mucus but lack of other berry extracts have been evaluated in clinical study. Thus, a 9-week add-on randomised controlled trial was conducted to explore the impact of blueberry and grape seed extract (BGE) combinations traditional therapy for H. pylori eradication. In results, we found that there was no significant difference of eradication rate between the berry extract group and placebo group in the intention-to-treat analysis and in the per-protocol analysis (94.64% versus 84.62%, p = 0.085). Diarrhoea, constipation and epigastric pain were observed increasing during ingestion of the berry extract in some cases. In conclusion, this study indicated that no significant difference existed between the BGE extract group and placebo group in eradication rate under triple therapy.
In most Old world monkey species, TRIM5α plays a role in combating retroviruses and restricting HIV-1. Alongside TRIM5α, the TRIMCyp fusion gene formed by the retrotransposition of a CypA pseudogene cDNA to 3' terminal or 3'-UTR of TRIM5 gene in these monkeys has become a key research area in anti HIV-1 factors. The regional differences, gene frequencies, genotypes, and retrovirus restrictive activities of TRIMCyp vary among different primate species. While the frequencies of cynomolgus TRIMCyp have been studied in several areas of Southeast Asia, the frequency and prevalence of cynomolgus TRIMCyp in China remains unclear. In this study, we screened 1, 594 cynomolgus samples from 11 monkey manufacturers located across 5 provinces in China. Our results showed that the frequencies of TRIMCyp range from 7.65% to 19.79%, markedly lower than the frequencies found in monkey species in the Philippines, Malaysia and Indonesia (ranging from 34.85% to 100%). We speculate that potentially the latter were isolated groups established since 1978. The NE haplotype frequencies of cynomolgus TRIMCyp were 4.93% in China, also significantly lower than those found in species in the Philippines, Malaysia and Indonesia (from 11.1% to 14.3%). Our research provides interesting findings that contribute towards a more firm basis of further studies of HIV-1 animal models and relevant pathogenesis.
Human Pituitary Tumour Transforming Gene 1 (PTTG1) is an oncoprotein involved in maintaining chromosome stability and acts as a biomarker for a panel of cancers. In this study, we endeavoured to generate an RNA aptamer against PTTG1. The RNA aptamer, SECURA-3 has an estimated equilibrium dissociation constant of 16.41 ± 6.4 nM. The aptamer was successfully harnessed in several diagnostic platforms including ELASA, aptamer-based dot blot and aptamer-based western blot. SECURA-3 was also unveiled as a potential probe that could replace its counterpart antibody in the histostaining-based detection of PTTG1 in HeLa and MCF-7 formalin-fixed paraffin-embedded cell blocks. In the aspect of therapeutics, SECURA-3 RNA aptamer demonstrates an antagonistic effect by antagonizing the interaction between PTTG1 and CXCR2, as revealed in the in vitro competitive nitrocellulose filter binding assay and dual-luciferase reporter assay in HeLa cells. As the first anti-PTTG1 aptamer, SECURA-3 RNA aptamer has immense diagnostic and therapeutic properties.
π-Acidic triangular silver(i) 3,5-bis(trifluoromethyl)pyrazolate (Ag3pz3) can form 1 : 1 adducts with dibenzothiophene (DBT), 4,6-dimethyldibenzothiophene (DMDBT), benzothiophene (BT), and 2,5-dimethylthiophene (DMT), which are stabilized by weak AgS and AgC contacts and sometimes by π-π stacking and, therefore, may represent a weak interaction model for some adsorptive desulfurization processes.
Anion exchange membrane fuel cells (AEMFCs) have emerged as a promising alternative to proton exchange membrane fuel cells (PEMFCs) due to their adaptability to low-cost stack components and non-noble-metals catalysts. However, the poor alkaline resistance and low OH- conductivity of anion exchange membranes (AEMs) have impeded the large-scale implementation of AEMFCs. Herein, the preparation of a new type of AEMs with crown ether macrocycles in their main chains via a one-pot superacid catalyzed reaction was reported. The study aimed to examine the influence of crown ether cavity size on the phase separation structure, ionic conductivity and alkali resistance of anion exchange membranes. Attributed to the self-assembly of crown ethers, the poly (crown ether) (PCE) AEMs with dibenzo-18-crown-6-ether (QAPCE-18-6) exhibit an obvious phase separated structure and a maximum OH- conductivity of 122.5 mS cm-1 at 80 °C (ionic exchange capacity is 1.51 meq g-1). QAPCE-18-6 shows a good alkali resistance with the OH- conductivity retention of 94.5% albeit being treated in a harsh alkali condition. Moreover, the hydrogen/oxygen single cell equipped with QAPCE-18-6 can achieve a peak power density (PPD) of 574 mW cm-2 at a current density of 1.39 A cm-2.