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Abstract Background Alginate oligosaccharides (AOs) are the degradation products of alginate, a natural polysaccharide abundant in brown algae. AOs generated by enzymatic hydrolysis have diverse bioactivities and show broad application potentials. AOs production via enzymolysis is now generally with sodium alginate as the raw material, which is chemically extracted from brown algae. In contrast, AOs production by direct degradation of brown algae is more advantageous on account of its cost reduction and is more eco-friendly. However, there have been only a few attempts reported in AOs production from direct degradation of brown algae. Results In this study, an efficient Laminaria japonica-decomposing strain Pseudoalteromonas agarivorans A3 was screened. Based on the secretome and mass spectrum analyses, strain A3 showed the potential as a cell factory for AOs production by secreting alginate lyases to directly degrade L. japonica. By using the L. japonica roots, which are normally discarded in the food industry, as the raw material for both fermentation and enzymatic hydrolysis, AOs were produced by the fermentation broth supernatant of strain A3 after optimization of the alginate lyase production and hydrolysis parameters. The generated AOs mainly ranged from dimers to tetramers, among which trimers and tetramers were predominant. The degradation efficiency of the roots reached 54.58%, the AOs production was 33.11%, and the AOs purity was 85.03%. Conclusion An efficient, cost-effective and green process for AOs production directly from the underutilized L. japonica roots by using strain A3 was set up, which differed from the reported processes in terms of the substrate and strain used for fermentation and the AOs composition. This study provides a promising platform for scalable production of AOs, which may have application potentials in industry and agriculture.

Alginate oligosaccharides (AOS), products of alginate degradation by endotype alginate lyases, possess favorable biological activities and have broad applications. Although many have been reported, alginate lyases with homogeneous AOS products and secretory production by an engineered host are scarce. Herein, the alginate lyase AlyC7 from Vibrio sp. C42 was characterized as a trisaccharide-producing lyase exhibiting high activity and broad substrate specificity. With PelB as the signal peptide and 500 mM glycine as the additive, the extracellular production of AlyC7 in Escherichia coli reached 1122.8 U/mL after 27 h cultivation in Luria-Bertani medium. The yield of trisaccharides from sodium alginate degradation by the produced AlyC7 reached 758.6 mg/g, with a purity of 85.1%. The prepared AOS at 20 μg/mL increased the root length of lettuce, tomato, wheat, and maize by 27.5%, 25.7%, 9.7%, and 11.1%, respectively. This study establishes a robust foundation for the industrial and agricultural applications of AlyC7.

Abstract Icaritin has potential anticancer effects on various cancers, including multiple myeloma (MM). Recent studies claim that Icaritin can regulate the expression of noncoding RNAs (ncRNAs) in cancer development. This study aimed to investigate the role of circular RNA_0000190 (circ_0000190) and functional mechanism in Icaritin‐treated MM. The expression of circ_0000190 and miR‐301a was detected by quantitative real‐time polymerase chain reaction. Cell cycle, apoptosis, migration, and invasion were investigated using flow cytometry assay, and transwell assay, respectively. The expression of BAX, BCL2, MMP2, and CCND1 was detected by western blot. The predicted target relationship between circ_0000190 and miR‐301a was validated by dual‐luciferase reporter assay and RNA immunoprecipitation assay. The activation of JAK1/STAT3 pathway was examined using western blot. Circ_0000190 was strikingly downregulated in MM specimens and cell lines, and Icaritin promoted the expression of circ_0000190. In function, circ_0000190 overexpression promoted MM cell cycle arrest and apoptosis but restrained the ability of migration and invasion. Icaritin blocked the development of MM by increasing circ_0000190 expression. MiR‐301a was identified as a target of circ_0000190, and miR‐301a reintroduction largely abolished the effects of circ_0000190 overexpression. The activation of JAK1/STAT3 pathway was promoted by miR‐301a restoration. Icaritin played anticancer effects in MM partly by enhancing the expression of circ_0000190 and regulating the circ_0000190/miR‐301a pathway. This study enhanced the understanding of the mechanism of Icaritin associated with circRNAs in MM.

A feasible and umpolung strategy for the synthesis of structurally diverse β-amino ketones has been achieved through TEMPO mediated C-N coupling of cyclopropanols with nitrogen nucleophiles. Mechanism studies indicated that in situ generated enones derived from cyclopropanols are the key intermediates and TEMPO play multiple roles, including radical initiator, trapping reagent, a porter of β-hydrogen and an in situ base. This protocol features broad substrate scope, good scalability and good to excellent yields and provides an alternative and complementary approach to the synthesis of structurally important β-amino ketone scaffolds under metal and additive-free conditions. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy and safety of solifenacin in the treatment of bladder spasms after urethroplasty. Patients underwent urethroplasty were randomly assigned to the study group ( n = 165) and the control group ( n = 150). Patients in the study group were treated with solifenacin for 7 days. Patients in the control group were placebo. Each group was further divided into four subgroups: paracentetic suprapubic cystostomy subgroup, traditional suprapubic cystostomy subgroup, former suprapubic cystostomy subgroup, and urethral catheter subgroup. A visual analogue scale (VAS) was used to measure the severity of bladder spasms. The mean duration of spasms, the frequency of spasms, and the incidences of urine extravasation and radiating pain were recorded each day. There were no significant differences in the VAS scores and mean duration of bladder spasms between the study and control groups . However, there was a significantly lower VAS score in the patients taking solifenacin in the paracentetic suprapubic cystostomy subgroup ( p < .05). A similar tendency was noted in the mean duration of bladder spasms in this subgroup. In a comparison of the daily and nightly frequency of spasms within the four subgroups, a significant improvement was noted in the control group within 5 days. A similar difference was not noted within 6 days in the study group. The short-term therapy with solifenacin is an effective and safe method for decreasing the frequency of bladder spasms after urethroplasty. Patients undergoing paracentetic suprapubic cystostomy might be the only subset to benefit from this treatment.