Summary of evidence to facilitate the implementation of advance care planning among advanced cancer patients. / ä¿ƒè¿›æ™šæœŸç™Œç—‡æ‚£è€ é¢„ç«‹åŒ»ç–—ç §æŠ¤è®¡åˆ’å®žæ–½çš„è¯æ®æ€»ç»“.

Advance care planning (ACP) is designed to ensure that patients lacking autonomous decision-making capacity receive medical services in accordance with their expectations and preferences. Individuals with advanced cancer are a crucial target for ACP implementation. However, the current practice of ACP in this group in China is suboptimal, demanding high-quality implementation evidence to strengthen ACP in the clinical practice of patients with advanced cancer. The existing literature can be summarized into 27 pieces of evidence across 7 dimensions, including initiation time, intervention content, intervention providers, intervention modalities, communication skills, outcome indicators, and environmental support. The aforementioned evidence could provide crucial support for improving ACP implementation for patients with advanced cancer. Subsequent research efforts should integrate patient preferences and explore the most suitable implementation strategies for ACP in the Chinese population with advanced cancer, considering diverse aspects such as traditional culture, ACP education and training, legislative support, and healthcare system refinement.

Chitin Deacetylase from Bacillus aryabhattai TCI-16: Heterologous Expression, Characterization, and Deacetylation Performance.

Chitin deacetylase (CDA) removes the acetyl group from the chitin molecule to generate chitosan in a uniform, high-quality deacetylation pattern. Herein, BaCDA was a novel CDA discovered from our previously isolated Bacillus aryabhattai strain TCI-16, which was excavated from mangrove soil. The gene BaCDA was cloned and overexpressed in Escherichia coli BL21 (DE3) to facilitate its subsequent purification. The purified recombinant protein BaCDA was obtained at a concentration of about 1.2 mg/mL after Ni2+ affinity chromatography. The molecular weight of BaCDA was around 28 kDa according to the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis. In addition, BaCDA exhibited a significant deacetylation effect on colloidal chitin, and the deacetylation degree was measured from the initial 25.69 to 69.23% by Fourier transform infrared (FT-IR) spectroscopy. Scanning electron microscopy (SEM) observation showed that the surface of colloidal chitin after enzymatic digestion was rough, the crystal fibers disappeared, and the chitin structure was loose and porous with grooves. The results of electrospray ionization mass spectrometry (ESI-MS) showed that BaCDA had full-deacetylation activity against (GlcNAc)4. Molecular docking revealed that BaCDA had an open active pocket capable of binding to the GlcNAc unit. This study not only provides a novel enzymatic resource for the green and efficient application of chitin but also helps to deepen the understanding of the catalytic mechanism of CDA.

Co-production of surfactin and fengycin by Bacillus subtilis BBW1542 isolated from marine sediment: a promising biocontrol agent against foodborne pathogens.

Pathogenic bacteria contaminations and related diseases in food industries is an urgent issue to solve. The present study aimed to explore natural food biopreservatives from microorganisms. Using dilution-plate method, a strain BBW1542 with antimicrobial activities against various foodborne pathogenic bacteria was isolated from the seabed silt of Beibu Gulf, which was identified as Bacillus subtilis by the morphological observation and 16S rDNA sequences. The antimicrobial substances of B. subtilis BBW1542 exhibited an excellent stability under cool/heat treatment, UV irradiation, acid/alkali treatment, and protease hydrolysis. The genome sequencing analysis and antiSMASH prediction indicated that B. subtilis BBW1542 contained the gene cluster encoding lipopeptides and bacteriocin subtilosin A. MALDI-TOF-MS analysis showed that the lipopeptides from B. subtilis BBW1542 contained C14 and C15 surfactin homologues, together with fengycin homologues of C18 fengycin A/C16 fengycin B and C19 fengycin A/C17 fengycin B. In silico analysis showed that an eight-gene (sboA-albABCDEFG) operon was involved in the biosynthesis of subtilosin A in B. subtilis BBW1542, and the encoded subtilosin A presented an evident closed-loop structure containing 35 amino acids with a molecular weight of 3425.94 Da. Overall, the antagonistic B. subtilis BBW1542 displayed significant resource value and offered a promising alternative in development of food biopreservation. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05864-3.

Stages of readiness for advance care planning: Systematic review and meta-analysis of prevalence rates and associated factors.

BACKGROUND: Advance care planning has been widely recommended to respect the medical care preferences of patients in the final stages of life. However, uptake of advance care planning in healthcare settings remains suboptimal. It may be beneficial to take into account individuals' readiness for advance care planning based on the stages to change identified in the Transtheoretical Model. OBJECTIVE: To identify the measurements used to assess readiness of advance care planning based on the Transtheoretical Model, to pool the prevalence of readiness stages, and to summarize the factors affecting people's readiness for advance care planning. DESIGN: Systematic review and meta-analysis. METHODS: We systematically searched the databases of PubMed, EMBASE, The Cochrane Library, CINAHL, and Web of Science for relevant studies from inception to February 2023. A random effects model was used to estimate the pooled prevalence. And a narrative review on the factors associated with stages of readiness was conducted. RESULTS: This meta-analysis included 25 studies involving a total of 4237 individuals. The precontemplation stage was the most commonly identified stage of readiness among advance care planning behaviors (26-72 %). The prevalence of readiness stages for advance care planning varied among different types of behavior. The behavior of "talking to health care proxy/family/loved ones about thoughts on quality versus quantity of life" had the highest level of readiness among all listed behaviors, followed by "talking to health care proxy/family/loved ones about living will", "signing a health care proxy form" and "signing a living will", "signing an advance directive", as well as "talking to doctors about living will". Regarding to influencing factors, a majority of sociodemographic and clinical factors did not show consistent associations with readiness, but some studies did suggest potential links with age, health status, countries, type of assessment, core structures of the Transtheoretical Model, and intervention modalities. CONCLUSIONS: A majority of individuals were unaware of advance care planning. There is an urgent need to promote readiness for such planning. Starting with preliminary activities such as "talking to health care proxy/family/loved ones about thoughts on quality versus quantity of life" can help initiate advance care planning. Better integration of the Transtheoretical Model and interventions into the research of advance care planning readiness are needed. REGISTRATION: Not registered.

Structural and enzymatic characterization of a novel metallo-serine keratinase KerJY-23.

KerJY-23 was a novel keratinase from feather-degrading Ectobacillus sp. JY-23, but its enzymatic characterization and structure are still unclear. In this study, the KerJY-23 was obtained by heterologous expression in Escherichia coli BL21(DE3), and enzymatic properties indicated that KerJY-23 was optimal at 60 °C and pH 9.0 and could be promoted by divalent metal ions or reducing agents. Furthermore, KerJY-23 had a broad substrate specificity towards casein, soluble keratin, and expanded feather powder, but its in vitro degradation against chicken feathers required an additional reducing agent. Homology modeling indicated that KerJY-23 contained a highly conserved zinc-binding HELTH motif and a His-Asp-Ser catalytic triad that belonged to the typical characteristics of M4-family metallo-keratinase and serine-keratinase, respectively. Molecular docking revealed that KerJY-23 achieved a reinforced binding on feather keratin via abundant hydrogen bonding interactions. This work not only deepened understanding of the novel and interesting metallo-serine keratinase KerJY-23, but also provided a theoretical basis for realizing the efficient use of waste feather keratin.

Development of a predictive nomogram for 28-day mortality risk in non-traumatic or post-traumatic subarachnoid hemorrhage patients.

OBJECTIVE: Subarachnoid hemorrhage (SAH) is associated with high rates of mortality and permanent disability. At present, there are few definite clinical tools to predict prognosis in SAH patients. The current study aims to develop and assess a predictive nomogram model for estimating the 28-day mortality risk in both non-traumatic or post-traumatic SAH patients. METHODS: The MIMIC-III database was searched to select patients with SAH based on ICD-9 codes. Patients were separated into non-traumatic and post-traumatic SAH groups. Using LASSO regression analysis, we identified independent risk factors associated with 28-day mortality and incorporated them into nomogram models. The performance of each nomogram was assessed by calculating various metrics, including the area under the curve (AUC), net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA). RESULTS: The study included 999 patients with SAH, with 631 in the non-traumatic group and 368 in the post-traumatic group. Logistic regression analysis revealed critical independent risk factors for 28-day mortality in non-traumatic SAH patients, including gender, age, glucose, platelet, sodium, BUN, WBC, PTT, urine output, SpO2, and heart rate and age, glucose, PTT, urine output, and body temperature for post-traumatic SAH patients. The prognostic nomograms outperformed the commonly used SAPSII and APSIII systems, as evidenced by superior AUC, NRI, IDI, and DCA results. CONCLUSION: The study identified independent risk factors associated with the 28-day mortality risk and developed predictive nomogram models for both non-traumatic and post-traumatic SAH patients. The nomogram holds promise in guiding prognosis improvement strategies for patients with SAH.

Inhibition of spastin impairs motor function recovery after spinal cord injury.

Promoting axonal regeneration is an effective strategy for recovery from traumatic spinal cord injury (SCI). Spastin, a microtubule-severing protein, modulates axonal outgrowth and branch formation by regulating microtubule dynamics. However, the exact role of spastin during recovery from SCI remains unknown. Therefore, we utilized a hemisection injury model of the mouse spinal cord and explored the effect of spastin using a spastin inhibitor, spastazoline. Results showed that spastazoline significantly suppressed the microtubule-severing activity of spastin in COS-7 cells and inhibited the promoting effect of spastin on neurite outgrowth in primarily cultured hippocampal neurons. The protein expression level of spastin was significantly upregulated in the injured spinal cord. Injured mice showed impaired motor functions, which included increased toe-off angle and foot fault steps and decreased stride length and Basso mouse scale score. Notably, these motor function impairments were aggravated by the application of spastazoline. Inhibition of spastin exacerbated neurogenesis impairment, as demonstrated by neuronal nuclei antigen staining, the inflammatory response, as shown by Iba-1 and GFAP staining, and axonal regeneration impairment, as shown by 5-hydroxytryptamine staining. Furthermore, mass spectrometry analysis revealed that the inhibition of spastin resulted in numerous dysregulated differentially expressed proteins that were closely associated with vesicle organization and transport. Taken together, our data suggest that spastin is critical for recovery from SCI and may be a potential target for the treatment of SCI.

Effective biodegradation on chicken feather by the recombinant KerJY-23 Bacillus subtilis WB600: A synergistic process coupled by disulfide reductase and keratinase.

Keratin wastes are abundantly available but rich in hard-degrading fibrous proteins, and the keratinase-producing microorganisms have gained significant attention due to their biodegradation ability against keratinous materials. In order to improve the degradation efficiency of feather keratins, the keratinase gene (kerJY-23) from our previously isolated feather-degrading Ectobacillus sp. JY-23 was overexpressed in Bacillus subtilis WB600 strain. The recombinant KerJY-23 strain degraded chicken feathers rapidly within 48 h, during which the activities of disulfide reductase and keratinase KerJY-23 were sharply increased, and the free amino acids especially the essential phenylalanine and tyrosine were significantly accumulated in feather hydrolysate. The results of structural characterizations including scanning electron microscopy, Fourier transform infrared spectrum, X-ray diffraction, and X-ray photoelectron spectroscopy, demonstrated that the feather microstructure together with the polypeptide bonds and SS bonds in feather keratins were attacked and destroyed by the recombinant KerJY-23 strain. Therefore, the recombinant KerJY-23 strain contributed to feather degradation through the synergistic action of the secreted disulfide reductase to break the SS bonds and keratinase (KerJY-23) to hydrolyze the polypeptide bonds in keratins. This study offers a new insight into the underlying mechanism of keratin degradation, and provides a potential recombinant strain for the valorization of keratin wastes.

Effects of different processing (Paozhi) on structural characterization and antioxidant activities of polysaccharides from Cistanche deserticola.

In this study, five polysaccharides were extracted from processed Cistanche deserticola. The processing included crude product, enzymatic hydrolysis, hot air drying, stir-baking with wine and high-pressure steaming, and these polysaccharides were named as CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs and HPS-CDPs, respectively. The structural characteristics and biological activities were explored. The results showed that processing changed properties of C. deserticola polysaccharides. CP-CDPs had the highest brightness value L*(93.84) and carbohydrate content (61.27 %). EH-CDPs had minimum Mw (1531.50 kDa), while SBW-CDPs had maximum Mw (2526.0 kDa). Glucose was major predominant monosaccharide in CP-CDPs (89.82 %), HAD-CDPs (79.3 %), SBW-CDPs (59.41 %) and HPS-CDPs (63.86 %), while galactose was major monosaccharide in EH-CDPs (29.44 %). According to SEM, SBW-CDPs showed compact structures, while HPS-CDPs and HAD-CDPs had similar looser structure than SBW-CDPs; meanwhile, CP-CDPs showed irregular agglomeration shape and EH-CDPs was dense blocky shape. The AFM showed SBW-CDPs had the largest molecular chain than other polysaccharides. When scavenging activity reaching 50 %, the concentrations of CP-CDPs, EH-CDPs, HAD-CDPs, SBW-CDPs, HPS-CDPs are 2.25, 0.25, 0.75, 1.8 and 1.5 mg/mL, respectively. This study sheds light on the effects of traditional Chinese medicine processing on characteristics, bioactivities of C. deserticola polysaccharides, and provides the basis for applications in food and pharmaceutical industries.

A marine lipopeptides-producing Bacillus amyloliquefaciens HY2-1 with a broad-spectrum antifungal and antibacterial activity and its fermentation kinetics study.

The antagonistic Bacillus amyloliquefaciens HY2-1 was a marine microbiology that was isolated previously from the seabed silt of Beibu Gulf in China by dual culture with Penicillium digitatum. As a continuous study, the present work focused on evaluating the antimicrobial activity, identifying the produced active components, and revealing the fermentation characteristics of B. amyloliquefaciens HY2-1, respectively. It was found that B. amyloliquefaciens HY2-1 exhibited a broad-spectrum antimicrobial activity against the tested seven phytopathogenic fungi and five pathogenic bacteria by producing Bacillus lipopeptides such as fengycin A (C14 to C19 homologues) and surfactin (C14 and C15 homologues). Morphological observation of P. digitatum under light microscope, scanning electron microscopy, transmission electron microscopy, and fluorescence microscope inferred that B. amyloliquefaciens exerted the antagonistic activity by damaging the fungal cell membrane, thus inhibiting the mycelium growth and sporification of phytopathogenic fungi. As a marine microbiology, our results showed that B. amyloliquefaciens could survive and metabolize even at the culture condition with 110 g/L of NaCl concentration, and the produced antimicrobial compounds exhibited excellent thermostability and acid-alkali tolerance. The dynamic models were further constructed to theoretically analyze the fermentation process of B. amyloliquefaciens HY2-1, suggesting that the synthesis of antimicrobial compounds was coupled with both cell growth and cell biomass. In conclusion, the marine lipopeptides-producing B. amyloliquefaciens HY2-1 showed a promising prospect to be explored as a biocontrol agent for plant disease control of crops and postharvest preservation of fruits and vegetables, especially due to its outstanding stress resistance and the broad-spectrum and effective antagonist on various phytopathogenic fungi.

Digital health interventions to support family caregivers: An updated systematic review.

Objective: Chronic diseases are the leading causes of death and disability in the U.S., and disease management largely falls onto patients' family caregivers. The long-term burden and stress of caregiving negatively impact caregivers' well-being and ability to provide care. Digital health interventions have the potential to support caregivers. This article aims to provide an updated review of interventions using digital health tools to support family caregivers and the scope of the Human-Centered Design (HCD) approaches. Methods: We conducted a systematic search on July 2019 and January 2021 in PubMed, CINAHL, Embase, Cochrane Library, PsycINFO, ERIC, and ACM Digital Library, limiting to 2014-2021 to identify family caregiver interventions assisted by modern technologies. The Mixed Methods Appraisal Tool and the Grading of Recommendations Assessment, Development and Evaluation were used to evaluate the articles. Data were abstracted and evaluated using Rayyan and Research Electronic Data Capture. Results: We identified and reviewed 40 studies from 34 journals, 10 fields, and 19 countries. Findings included patients' conditions and relationships with family caregivers, how the technology is used to deliver the intervention, HCD methods, theoretical frameworks, components of the interventions, and family caregiver health outcomes. Conclusion: This updated and expanded review revealed that digitally enhanced health interventions were robust at providing high-quality assistance and support to caregivers by improving caregiver psychological health, self-efficacy, caregiving skills, quality of life, social support, and problem-coping abilities. Health professionals need to include informal caregivers as an essential component when providing care to patients. Future research should include more marginalized caregivers from diverse backgrounds, improve the accessibility and usability of the technology tools, and tailor the intervention to be more culturally and linguistically sensitive.

Venous thromboembolism prophylaxis and mortality in patients with spinal fractures in ICUs.

BACKGROUND: Spinal fracture is a common traumatic condition in orthopaedics, accounting for 5%-6% of total body fractures, and is a high-risk factor for venous thromboembolism (VTE), which seriously affects patient prognosis. AIM: The aim of this study was to determine the impact of VTE prophylaxis on the prognosis of patients with spinal fractures in intensive care units (ICUs) and to provide a scientific basis for clinical treatment and nursing. DESIGN: A retrospective study of patients with spinal fractures from the multicenter eICU Collaborative Research Database. METHOD: The outcomes of this study were ICU mortality and in-hospital mortality. Patients were divided into the VTE prophylaxis (VP) and no VTE prophylaxis (NVP) groups according to whether they had undergone VTE prophylaxis during their ICU admission. The association between groups and outcomes were analysed using Kaplan-Meier (KM) survival curve, log-rank test and the Cox proportional-hazards regression model. RESULTS: This study included 1146 patients with spinal fractures: 330 in the VP group and 816 in the NVP group. KM survival curves and log-rank tests revealed that both ICU and in-hospital survival probabilities in the VP group were significantly higher than in the NVP group. After the Cox model was adjusted for all covariates, the hazard ratio for ICU mortality in the VP group was 0.38 (0.19-0.75); the corresponding value for in-hospital mortality in the VP group was 0.38 (0.21-0.68). CONCLUSIONS: VTE prophylaxis is associated with reduced ICU and in-hospital mortality in patients with spinal fractures in ICUs. More research is necessary to further define specific strategies and optimal timing for VTE prophylaxis. RELEVANCE TO CLINICAL PRACTICE: This study provides the basis that VTE prophylaxis may be associated with improved prognosis in patients with spinal fractures in ICUs. In clinical practice, an appropriate modality should be selected for VTE prophylaxis in such patients.

Type and dose-response effect of adverse childhood experiences in predicting depression: A systematic review and meta-analysis.

BACKGROUND: Researchers have documented that adverse childhood experiences (ACEs) are associated with adverse long-term consequences for mental health, including increased risk for depression. However, the type and dose-response effects of ACE on depression risk need further exploration. OBJECTIVE: We aimed to synthesize the evidence on the relationship between ACEs measured by ACE International Questionnaire (ACE-IQ) and depression in type and quantity. PARTICIPANTS AND SETTING: Individuals with ACEs. METHODS: A systematic search was carried out of all published articles, up to November 2022, in eight electronic databases. Fixed- and random-effect models and dose-response were used. RESULTS: Exposure to ACEs, including household dysfunction, was associated with a higher risk of depression (ORs ranged from 1.34 to 3.17). The numbers of ACE acted as a nonlinear predictor of depression. CONCLUSIONS: These analyses provided important evidence that ACEs, regardless of type or quantity, may be a risk factor for depression development. Prevention of ACEs and interventions for supporting those affected by ACEs are necessary.

Repair of missing linker defects in UiO-66 by a "molecular patch" boosting the 1-hexene hydroformylation reaction.

Fabrication of MOFs with missing linker defects has become a common means to improve catalytic performances. However, the stability of the defects deserves to be investigated first. In this work, we found that 3-phenylpropionaldehyde (3-PPA) could coordinate with the missing linker defects of UiO-66, which highlighted the instability of the missing linker defects. 3-PPA acted as a molecular patch for the modification of the Rh/UiO-66 catalyst, which repaired the open Zr6 sites and resulted in a remarkable improvement of aldehyde selectivity (from 50.0% to 89.6%) in 1-hexene hydroformylation.

Correction: Controlling CO2 hydrogenation selectivity by Rh-based catalysts with different crystalline phases of TiO2.

Correction for 'Controlling CO2 hydrogenation selectivity by Rh-based catalysts with different crystalline phases of TiO2' by Fenghai Cao et al., Chem. Commun., 2022, 58, 4219-4222, https://doi.org/10.1039/D2CC00472K.

Phosphorylation mutation impairs the promoting effect of spastin on neurite outgrowth without affecting its microtubule severing ability.

Spastin, a microtubule-severing enzyme, is known to be important for neurite outgrowth. However, the role of spastin post-translational modification, particularly its phosphorylation regulation in neuronal outgrowth, remains unclear. This study aimed to investigate the effects of eliminating spastin phosphorylation on the neurite outgrowth of rat hippocampal neurons. To accomplish this, we constructed a spastin mutant with eleven potential phosphorylation sites mutated to alanine. The phosphorylation levels of the wildtype spastin (WT) and the mutant (11A) were then detected using Phos-tag SDS-PAGE. The spastin constructs were transfected into COS7 cells for the observation of microtubule severing, and into rat hippocampal neurons for the detection of neuronal outgrowth. The results showed that compared to the spastin WT, the phosphorylation levels were significantly reduced in the spastin 11A mutant. The spastin mutant 11A impaired its ability to promote neurite length, branching, and complexity in hippocampal neurons, but did not affect its ability to sever microtubules in COS7 cells. In conclusion, the data suggest that mutations at multiple phosphorylation sites of spastin do not impair its microtubule cleavage ability in COS7 cells, but reduce its ability to promote neurite outgrowth in rat hippocampal neurons.

Rab3A interacts with spastin to regulate neurite outgrowth in hippocampal neurons.

Investigating novel mechanisms of neurite outgrowth via cytoskeleton is critical for developing therapeutic strategies against neural disorders. Rab3A is a vesicle-related protein distributed throughout the nervous system, but the detailed mechanism related to cytoskeleton remains largely unknown. Our previous reports show that spastin serves microtubule to regulate neurite outgrowth. Here, we asked whether Rab3A could function via modulating spastin during neuronal development. The results revealed that Rab3A colocalized with spastin in cultured hippocampal neurons. Immunoprecipitation assays showed that Rab3A physically interacted with spastin in rat brain lysates. Rab3A overexpression significantly induced spastin degradation; this effect was reversed by leupeptin- or MG-132- administration, suggesting the lysosomal and ubiquitin-mediated degradation system. Immunofluorescence staining further confirmed that Rab3A and spastin immune-colocalized with the lysosome marker lysotracker. In COS7 cells, Rab3A overexpression significantly downregulated spastin expression and abolished the spastin-mediated microtubule severing. Furthermore, overexpression inhibited while genetic knockdown of Rab3A promoted neurite outgrowth. However, this inhibitory effect on neurite outgrowth in hippocampal neurons could be reversed via co-transfection of spastin, indicating that Rab3A functions via its interaction protein spastin. In general, our data identify an interaction between Rab3A and spastin, and this interaction affects the protein stability of spastin and eliminates its microtubule severing function, thereby modulating neurite outgrowth.

Nitrogen Removal Characteristics of a Marine Denitrifying Pseudomonas stutzeri BBW831 and a Simplified Strategy for Improving the Denitrification Performance Under Stressful Conditions.

A marine aerobic denitrifying bacterium was isolated and identified as Pseudomonas stutzeri BBW831 from the seabed silt of Beibu Gulf in China. According to the genome analysis, P. stutzeri BBW831 possessed a total of 14 genes (narG, narH, narI, narJ, napA, napB, nirB, nirD, nirS, norB, norC, norD, norQ, and nosZ) responsible for fully functional enzymes (nitrate reductase, nitrite reductase, nitric oxide reductase, and nitrous oxide reductase) involved in the complete aerobic denitrification pathway, suggesting that it had the potential for reducing nitrate to the final N2. Denitrification results showed that P. stutzeri BBW831 exhibited efficient nitrogen removal characteristics. Within 12 h, the NO3--N removal efficiency and rate reached 94.64% and 13.09 mg·L-1·h-1 under 166.10 ± 3.75 mg/L NO3--N as the sole nitrogen source, and removal efficiency of the mixed nitrogen (50.50 ± 0.55, 62.28 ± 0.74, and 64.26 ± 0.90 mg/L of initial NH4+-N, NO3--N, and NO2--N, respectively) was nearly 100%. Furthermore, a simplified strategy, by augmenting the inoculation biomass, was developed for promoting the nitrogen removal performance under high levels of NO2--N and salinity. As a result, the removal efficiency of the initial NO2--N up to approximately 130 mg/L reached 99.46% within 8 h, and the NO3--N removal efficiency achieved at 59.46% under the NaCl concentration even up to 50 g/L. The C/N ratio of 10 with organic acid salt such as trisodium citrate and sodium acetate as the carbon source was most conducive for cell growth and nitrogen removal by P. stutzeri BBW831, respectively. In conclusion, the marine P. stutzeri BBW831 contained the functional genes responsible for a complete aerobic denitrification pathway (NO3--N → NO2--N → NO → N2O → N2), and had great potential for the practical treatment of high-salinity nitrogenous mariculture wastewater.

Isolation, characterization, and genome sequencing of a novel chitin deacetylase producing Bacillus aryabhattai TCI-16.

Chitin deacetylase (CDA) is a chitin degradation enzyme that catalyzes the conversion of chitin to chitosan by the deacetylation of N-acetyl-D-glucosamine residues, playing an important role in the high-value utilization of waste chitin. The shells of shrimp and crab are rich in chitin, and mangroves are usually recognized as an active habitat to shrimp and crab. In the present study, a CDA-producing bacterium, strain TCI-16, was isolated and screened from the mangrove soil. Strain TCI-16 was identified and named as Bacillus aryabhattai TCI-16, and the maximum CDA activity in fermentation broth reached 120.35 ± 2.40 U/mL at 36 h of cultivation. Furthermore, the complete genome analysis of B. aryabhattai TCI-16 revealed the chitin-degrading enzyme system at genetic level, in which a total of 13 putative genes were associated with carbohydrate esterase 4 (CE4) family enzymes, including one gene coding CDA, seven genes encoding polysaccharide deacetylases, and five genes encoding peptidoglycan-N-acetyl glucosamine deacetylases. Amino acid sequence analysis showed that the predicted CDA of B. aryabhattai TCI-16 was composed of 236 amino acid residues with a molecular weight of 27.3 kDa, which possessed a conserved CDA active like the known CDAs. However, the CDA of B. aryabhattai TCI-16 showed low homology (approximately 30%) with other microbial CDAs, and its phylogenetic tree belonged to a separate clade in bacteria, suggesting a high probability in structural novelty. In conclusion, the present study indicated that the novel CDA produced by B. aryabhattai TCI-16 might be a promising option for bioconversion of chitin to the value-added chitosan.

Extraction, Physicochemical Properties, Anti-Aging, and Antioxidant Activities of Polysaccharides from Industrial Hemp Residues.

A large amount of hemp polysaccharides remain in industrial hemp residues (IHR) after cannabidiol extraction, resulting in the waste of resources. Therefore, the systematic study of hemp polysaccharides is beneficial to the development of IHR in the future. In this study, the extraction of industrial hemp residues polysaccharide (IHRPs) was optimized by single-factor experiment and orthogonal experimental design. The optimum heating extraction conditions were extraction temperature 98 °C, solid-liquid ratio 1:10, extraction time 1 h, number of successive extractions 2, and pH at 4. The extraction ratio and the polysaccharide content were 20.12 ± 0.55% and 12.35 ± 0.26% at the conditions, respectively. Besides, the best alcohol precipitation conditions were pumping with 2 L/h, stirring continuously, and ice-water bath for 4 h. The crude IHRPs was further purified by column chromatography and the polysaccharide/protein contents of purified IHRPs were 34.44% and 1.61%. IHRPs was mainly made up of ten monosaccharides and some non-sugar components including organic acids, flavonoids, steroids, and glycoside. The FT-IR demonstrated the polysaccharide skeleton of IHRPs. Moreover, the DPPH and ABTS scavenging rate of IHRPs were 76.00% and 99.05% at the concentrations of 1 mg/mL. IHRPs could promote the epidermal cells proliferation and healing of cell scratches. Meanwhile, IHRPs could promoted the expression of anti-aging-related genes. Overall, IHRPs could be a desirable natural source of antioxidants and anti-aging products in many aspects.