Temperature-controlled microalgal biofilm detachment and harvesting assisted by ultrasonic from 3D porous substrates grafted with thermosensitive gels.

Microalgae have been renowned as the most promising energy organism with significant potential in carbon fixation. In the large-scale cultivation of microalgae, the 3D porous substrate with higher specific surface area is favorable to microalgae adsorption and biofilm formation, whereas difficult for biofilm detachment and microalgae harvesting. To solve this contradiction, N-isopropylacrylamide, a temperature-responsive gels material, was grafted onto the inner surface of the 3D porous substrate to form temperature-controllable interface wettability. The interfacial free energy between microalgae biofilm and the substrates increased from -63.02 mJ/m2 to -31.89 mJ/m2 when temperature was lowered from 32 °C to 17 °C, weakening the adsorption capacity of cells to the surface, and making the biofilm detachment ratio increased to 50.8%. When further cooling the environmental temperature to 4 °C, the detachment capability of microalgae biofilm kept growing. 91.6% of the cells in the biofilm were harvesting from the 3D porous substrate. And the biofilm detached rate was up to 19.84 g/m2/h, realizing the temperature-controlled microalgae biofilm harvesting. But, microalgae growth results in the secretion of extracellular polymeric substances (EPS), which enhanced biofilm adhesion and made cell detachment more difficult. Thus, ultrasonic vibration was used to reinforce biofilm detachment. With the help of ultrasonic vibration, microalgae biofilm detached rate increased by 143.45% to 41.07 g/m2/h. These findings provide a solid foundation for further development of microalgae biofilm detachment and harvesting technology.

Y chromosome microdeletions in Chinese men with infertility: prevalence, phenotypes, and intracytoplasmic sperm injection outcomes.

BACKGROUND: The incidence of Y chromosome microdeletions varies among men with infertility across regions and ethnicities worldwide. However, comprehensive epidemiological studies on Y chromosome microdeletions in Chinese men with infertility are lacking. We aimed to investigate Y chromosome microdeletions prevalence among Chinese men with infertility and its correlation with intracytoplasmic sperm injection (ICSI) outcomes. METHODS: This single-center retrospective study included 4,714 men with infertility who were evaluated at the Reproductive Center of the First Affiliated Hospital of Sun Yat-sen University between May 2017 and January 2021. Semen analysis and Y-chromosome microdeletion via multiplex polymerase chain reaction were conducted on the men. The study compared outcomes of 36 ICSI cycles from couples with male azoospermia factor (AZF)cd deletions with those of a control group, which included 72 ICSI cycles from couples without male Y chromosome microdeletions, during the same period. Both groups underwent ICSI treatment using ejaculated sperm. RESULTS: Among 4,714 Chinese men with infertility, 3.31% had Y chromosome microdeletions. The combined deletion of sY254 and sY255 in the AZFc region and sY152 in the AZFd region was the prevalent pattern of Y chromosome microdeletion, with 3.05% detection rate. The detection rates of AZF deletions in patients with normal total sperm count, mild oligozoospermia, severe oligozoospermia, cryptozoospermia, and azoospermia were 0.17%, 1.13%, 5.53%, 71.43%, and 7.54%, respectively. Compared with the control group, the AZFcd deletion group exhibited no significant difference in the laboratory results or pregnancy outcomes of ICSI cycles using ejaculated sperm. CONCLUSIONS: This is the largest epidemiological study on Y chromosome microdeletions in Chinese men with infertility. The study results underline the necessity for detecting Y chromosome microdeletion in men with infertility and severe sperm count abnormalities, especially those with cryptozoospermia. The combined deletion of sY254 and sY255 in the AZFc region and sY152 in the AZFd region was the most prevalent Y chromosome microdeletion pattern. Among patients with AZFcd deletion and ejaculated sperm, ICSI treatment can result in pregnancy outcomes, similar to those without AZFcd deletion.

Temperature-controlled microalgae biofilm adsorption/desorption in a thermo-responsive light-guided 3D porous photo-bioreactor for CO2 fixation.

Microalgae biofilm-based culture provides an efficient CO2 reduction and wastewater treatment method for its high photosynthetic efficiency and density. As supporting substrates for microalgae biofilm, porous materials have a big available adsorption area, but mutual shading makes it difficult to transmit external light to the internal surface for attached cells' photosynthesis. Thus, light-guided particles (SiO2) were introduced into photosensitive resin to fabricate a light-guided ordered porous photobioreactor (PBR) by 3D printing technology in this study. The space utilization of the PBR was significantly enhanced and the effective microalgae adsorption area was increased by 13.6 times. Further, a thermo-responsive hydrogel was grafted onto the surface of the substrate to form a smart temperature-controllable interface that could enhance microalgae adsorption and desorption in both directions. When the thermo-responsive layer received light, it would generate heat due to the hydrogel's photo-thermal effect. And the surface temperature would then raise to 33 °C, higher than the hydrogel phase transition point of 32 °C, making the surface shrinking and more hydrophobicity for microalgae cells attachment. The microalgae cells' adsorption capacity increased by 103%, resulting in a high microalgae growth rate of 3.572 g m-2 d-1. When turning off the light, the surface temperature would cool down to below 20 °C, the surface would shrink. And the biofilm shows a 564.7% increase in desorption ability, realizing temperature-controlled microalgae harvesting.

Comprehensive modeling and predicting light transmission in microalgal biofilm.

Biofilm-based microalgae culture combined with wastewater treatment is a promising biotechnology for environmental management. Light availability influences the accumulation of microalgal biomass and nutrient removal. A light attenuation model which comprehensively considered microalgal biofilm structure (density and biofilm thickness), pigments content, and extracellular polymeric substances content was developed to predict the light attenuation in biofilm according to the simplification of the radiative transfer equation. The predicted results were in good overall agreement with the experiment, with an average error of less than 9.02%. These factors (biofilm density, thickness, pigments content, and extracellular polymeric substances content) all contributed to the light intensity attenuation, but biofilm thickness caused the most dramatic attenuation under the same increment of relative change in actual culture. The scattering coefficient of the biofilm (0.433 m2/g) was less than that of the suspension (1.489 m2/g) under white incident light. It suggests that the dense structure of cells allows much light to be concentrated in the forward direction when transmitting. This model could be adopted to predict the light distribution in microalgal biofilm for the further design of efficient photobioreactors and the development of light optimization strategies.

How Interfacial Properties Affect Adhesion: An Analysis from the Interactions between Microalgal Cells and Solid Substrates.

Microalgal biofilm, a stable community of many algal cells attached to a solid substrate, plays a significant role in the efficient accumulation of renewable energy feedstocks, wastewater treatment, and carbon reduction. The adhesion tendency of microalgal cells on solid substrates is the basis for controlling the formation and development of microalgal biofilm. To promote the adhesion of microalgal cells on solid substrates, it is necessary to clarify which surface properties have to be changed in the most critical factors affecting the adhesion. However, there have been few systematic discussions on what surface properties influence the adhesion tendency of algal cells on solid substrates. In this study, the essential principle of microalgal cell adhesion onto solid substrates was explored from the perspective of the interaction energy between microalgal cells and solid substrates. The influence of surface properties between microalgal cells and solid substrates on interaction energies was discussed via extended Derjaguin-Landau-Verwey-Overbeek (eDLVO) theory and a sensitivity analysis. The results showed that surface properties, including surface potential (ξ) and surface free energy components, significantly affect the adhesion tendency of microalgal cells on different solid substrates. When the solid surface possesses positive charges (ξ > 0), reducing ξ or the electron donor components of the solid substrate (γs-) is an effective measure to promote microalgal cell adhesion onto the solid substrate. When the solid surface possesses negative charges (ξ < 0), an increase in either γs- or the absolute value of ξ should be avoided in the process of microalgae adhesion. Overall, this research provides a direction for the selection of solid substrates and a direction for surface modification to facilitate the adhesion tendency of microalgal cells on solid substrates under different scenarios.

Microalgae cultivation for antibiotic oxytetracycline wastewater treatment.

Microalgae-based technology provides a potential approach to biologically treating oxytetracycline (OTC) wastewater due to its environmental friendliness, low cost, and high efficiency. However, the OTC degradation and transformation characteristics by microalgae are still unclear and need further exploration. This study used microalgae Chlorella sorokiniana MB-1 for OTC wastewater treatment. The OTC with an initial concentration less than 50 mg L-1 promoted microalgae growth, while OTC with a concentration higher than 100 mg L-1 inhibited microalgae growth significantly. More than 99% OTC was removed with the biomass productivity up to 1.8 g L-1 when treated OTC with 10 mg L-1 initial concentration for 7 days. Chlorophyll and total sugar contents decreased, while protein and lipid contents increased compared to the control without OTC. The malondialdehyde content firstly reduced but subsequently enhanced when increased OTC concentration, while superoxide dismutase content gradually enhanced, manifesting that traces of OTC stimulate microalgae antioxidant capacity, while the increasing OTC caused further oxidative damage to microalgae cells. The removal pathways of OTC mainly include photolysis (75.8%), biodegradation (17.8%), biosorption (3.6%), and hydrolysis (2.7%). Overall, removing OTC by microalgae was confirmed to be an excellent technology for treating antibiotics wastewater whilst accumulating microalgae biomass.

Thermoresponsive Surfaces Grafted by Shrinkable Hydrogel Poly(N-isopropylacrylamide) for Controlling Microalgae Cells Adhesion during Biofilm Cultivation.

Microalgae is a promising candidate for reducing greenhouse gas and producing renewable biofuels. For microalgae biofilm cultivation, a strong adhesion ability of microalgae cells onto the surface is a prerequisite to resist the fluid shear stress, while strong adhesion is not of benefit to the biofilm harvesting process. To solve this dilemma, a thermoresponsive surface (TMRS) with lower critical solution temperature of 33 °C was made by grafting N-isopropylacrylamide onto a silicate glass slide. The wettability of the TMRS changed from hydrophilic (contact angle of 59.4°) to hydrophobic (contact angle of 91.6°) when the temperature rose from 15 to 35 °C, resulting in the increase of adhesion energy of the TMRS to Chlorella vulgaris cells by 135.6%. The experiments showed that the cells were more likely to attach onto the TMRS at the higher temperature of 35 °C owing to the surface microstructures generated by the hydrogel layer shrinkage, which is similar in size to the microalgae cells. And the cell coverage rate on TMRS increased by 32% compared to the original glass surface. Conversely, the cells separate easily from the TMRS at a lower temperature of 15 °C, and the cell adhesion density was reduced by 19% due to hydrogel layer swelling to a relatively flat surface.

The prevalence and risk factors for depressive symptoms in frontline nurses under COVID-19 pandemic based on a large cross-sectional study using the propensity score-matched method.

INTRODUCTION: To explore the prevalence of depressive symptoms and the associated risk factors in frontline nurses under COVID-19 pandemic. METHODS: This cross-sectional study was conducted from February 20, 2020 to March 20, 2020 and involved 562 frontline nurses. The effective response rate was 87.68%. After propensity score matched, there were 498 participants left. Extensive characteristics, including demographics, dietary habits, life-related factors, work-related factors, and psychological factors were collected based on a self-reported questionnaire. Specific scales measured the levels of sleep quality, physical activity, depressive symptoms, perceived organization support and psychological capital. Adjusted odds ratios and 95% confidence intervals were determined by binary paired logistic regression. RESULTS: Of the nurses enrolled in the study, 50.90% had depressive symptoms. Three independent risk factors were identified: poor sleep quality (OR = 1.608, 95% CI: 1.384-1.896), lower optimism of psychological capital (OR = 0.879, 95% CI: 0.805-0.960) and no visiting friend constantly (OR = 0.513, 95% CI: 0.286-0.920). CONCLUSIONS: This study revealed a considerable high prevalence of depressive symptoms in frontline nurses during the COVID-19 outbreak, and identified three risk factors, which were poor sleep quality, lower optimism of psychological capital, and no visiting friend constantly. Protecting mental health of nurses is important for COVID-19 pandemic control and their wellbeing. These findings enrich the existing theoretical model of depression and demonstrated a critical need for additional strategies that could address the mental health in frontline nurses for policymakers.

Risk factors and oncological outcomes of urethral recurrence in male patients with muscle invasive bladder cancer after radical cystectomy combined with urinary diversion: a propensity score-matched case control study.

BACKGROUND: Radical cystectomy (RC) is the primary treatment strategy for muscle invasive bladder cancer (MIBC). However, it carries a high risk of urethral recurrence (UR) in male patients. The risk factors and oncological outcomes of UR remain unclear. We aimed to identify the risk factors and oncological outcomes of UR in male patients with MIBC after RC combined with urinary diversion. METHODS: After propensity score matching, we evaluated 137 male patients with MIBC who underwent RC combined with urinary diversion at our center between January 1, 2007 and December 31, 2015. Patient demographics, comorbidity, and perioperative data were recorded. Univariate and multivariate Cox proportional hazards regression were used to estimate the hazard ratio and 95% confidence intervals. Cancer-specific survival (CSS) and overall survival (OS) were measured using the Kaplan-Meier curve with log-rank test. P < 0.05 was considered statistically significant. RESULTS: Of the 310 patients, 30 (9.7%) patients underwent UR. In the matched group, the independent risk factors of UR were history of TURB (HR = 3.069, P = 0.018), tumor stage (T3 vs. T2, HR = 3.997, P = 0.014; T4 vs. T2, HR = 2.962, P = 0.015), and tumor multifocality (HR = 2.854, P = 0.011). The CSS and OS of patients with UR were equivalent to the patients without UR (P = 0.295, P = 0.616). CONCLUSION: This propensity score-matched case-control study showed that UR is not rare in male patients with MIBC after RC combined with urinary diversion. We identified three independent risk factors of UR: history of TURB, tumor stage, and tumor mutifocality. The oncological outcomes were equivalent between patients with and without UR. These findings could help improve treatment strategies and follow-up schedules.

Development and validation of a clinical model to predict intraoperative hemodynamic instability in patients with pheochromocytomas surgery.

Although currently the primary strategy for the treatment of pheochromocytomas is surgery, it is associated with a high risk of intraoperative hemodynamic instability (IHD), even with adequate preoperative medical preparation, which may result in life-threatening situations. The aim of this study was to develop and validate a nomogram for preoperative prediction of IHD related to pheochromocytoma surgery. The development cohort consisted of 283 patients with pheochromocytoma who underwent unilateral laparoscopic or open adrenaletomy at our center between January 1, 2007 and December 31, 2016. The clinicopathological characteristics of each patient were recorded. The least absolute shrinkage and selection operator binary logistic regression model was used for data dimension reduction and feature selection, while multivariable logistic regression analysis was used to develop the prediction model. An independent cohort consisting of 119 consecutive patients from January 1, 2017 to December 31, 2018 was used for validation. The performance of the prediction model was assessed in regards to discrimination, calibration, and clinical usefulness. The predictors of this model included body mass index, coronary heart disease, tumor size, and preoperative use of crystal/colloid fluid. For the validation cohort, the model showed good discrimination with an area under the receiver operating characteristic of 0.767 (95% CI, 0.667-0.857) and good calibration (unreliability test, p = 0.852; Hosmer-Lemeshow test, p = 0.9309). Decision curve analysis demonstrated that the model was clinically useful. This nomogram to facilitate preoperative individualized prediction of IHD in patients with pheochromocytoma may help to improve the perioperative strategy and treatment outcome.

A new ureteroileal anastomosis technique in modified ileal orthotopic bladder substitution after radical cystectomy.

BACKGROUND: The aim of this study is to describe a modified technique in ileal orthotopic bladder substitution with a new ureteroileal anastomosis. CASE PRESENTATION: After a classic open radical cystectomy with bilateral pelvic lymphadenectomy was performed extraperitoneally, a 56-cm ileal segment was used to construct the spheroidal shape bladder substitution. The 8-cm long proximal and distal ends of the ileal segment were used as afferent limbs. Two-centimeter ileal segments of afferent limbs were detubularized and transversally tubularized. The elongated ileal tube was anastomosed with the ureter in an end-to-end fashion. The pathway of the ureteroileal anastomosis was placed between the abdominal cutaneous fat and the anterior rectus muscular sheath. Perioperative data and long-term functional outcomes were assessed. Between December 2011 and December 2015, seven male patients underwent this procedure with a median 46 (30-77) months follow-up in our hospital. There was no difference between preoperative and postoperative estimated glomerular filtration rates (Z = - 1.693, P = 0.09). One of 14 sides had ureteroileal anastomotic stenosis; two of 14 sides in one patient had ureteroileal anastomotic stenosis caused by invasion of pelvic recurrence 15 months postoperatively. Reflux was completely prevented by placing pressure on the corresponding point on the abdominal surface when voiding urine in all patients. CONCLUSIONS: We describe a feasible technique modification in detail, which provides some advantages for effective anti-reflux by mechanical finger pressing and abdominal contraction, a low incidence of stricture, and ease for a secondary operation in the long-term follow-up period.

Development and validation of a predictive model for predicting cardiovascular morbidity in patients after pheochromocytoma surgery.

OBJECTIVE: Although surgical resection is the primary treatment method for pheochromocytoma, it carries a high risk of morbidity, especially cardiovascular-related morbidity. There are no models for predicting cardiovascular morbidity after pheochromocytoma surgery. Thus, we developed and validated a model for the preoperative prediction of cardiovascular morbidity after pheochromocytoma surgery. DESIGN: The development cohort consisted of 262 patients who underwent unilateral laparoscopic or open pheochromocytoma surgery at our centre between 1 January 2007 and 31 December 2016. Patient's clinicopathologic data were recorded. The LASSO regression was used for data dimension reduction and feature selection; then, multivariable logistic regression analysis was used to develop the prediction model. An independent cohort consisting of 112 consecutive patients from 1 January 2017 and 31 December 2018 was used for validation. The performance of this prediction model was assessed with respect to discrimination, calibration and clinical usefulness. RESULTS: The predictors in this prediction model included body mass index, history of coronary heart disease, tumour size, intraoperative hemodynamic instability and use of crystal/colloid fluids preoperatively. In the validation cohort, the model showed good discrimination with an AUROC of 0.869 (95% CI, 0.797, 0.940) and good calibration (unreliability test, P = .852). Decision curve analysis demonstrated that the model was also clinically useful. CONCLUSION: This study presented a good nomogram that could facilitate the preoperative individualized prediction of cardiovascular morbidity after pheochromocytoma surgery, which may help improve perioperative strategy and good treatment outcomes.

Risk factors for postoperative cardiovascular morbidity after pheochromocytoma surgery: a large single center retrospective analysis.

Surgical resection is the primary treatment strategy for pheochromocytoma; however, it carries a high risk of morbidity and mortality, especially with respect to cardiovascular complications, which is the most common kinds of morbidity. The risk factors for morbidity remain unclear and require further exploration, moreover no studies focus on risk factors for cardiovascular morbidity. Herein we identified the risk factors for cardiovascular morbidity after pheochromocytoma surgery in Chinese patients. We retrospectively reviewed 262 patients who underwent unilateral surgical resection of pheochromocytoma at our center between 1 January 2007 and 31 December 2016. Patient demographics and extensive perioperative data were recorded and evaluated. Adjusted odds ratios and 95% confidence intervals were determined by multivariate logistic regression. Cut-off values and the area under the curve for continuous risk factors were calculated based on receiver operating characteristic curve analysis. A p-value <0.05 was considered statistically significant. Of the 262 patients, 63 (24.0%) had cardiovascular morbidity. The independent risk factors for cardiovascular morbidity were low body mass index, large radiographic tumor size, coronary heart disease, no preoperative crystal/colloid administration, and intraoperative hemodynamic instability; the corresponding odds ratio were 0.762 (p < 0.001), 1.208 (p = 0.010), 2.378 (p = 0.012), 2.720 (p = 0.011), and 4.764 (p = 0.001), respectively. The optimal cut-off values for body mass index and radiographic tumor size were 24.59 kg/m2 and 6.05 cm. We found that cardiovascular morbidity is common in patients after pheochromocytoma surgery. We identified five independent risk factors for cardiovascular morbidity. Identification of these risk factors may help to improve treatment strategies.

Effectiveness of a modified doctor-patient communication training Programme designed for surgical residents in China: a prospective, large-volume study at a single Centre.

BACKGROUND: Effective doctor-patient communication (DPC) is important to improve the quality of care and treatment outcomes. This study aimed to evaluate the effectiveness of a modified DPC training programme designed for surgical residents in China. METHODS: A total of 210 surgical residents from 7 specialties were recruited to participate in a communication skills training programme. The extended SEGUE scale was administered to supervisors, and a visual analogue scale (VAS) was administered to standardized patients (SPs) and trainees. Evaluations were conducted by comparing the pre-post scale scores (before, immediately after and 1 month after the programme). Training effects were assessed using the Friedman test and the intraclass correlation coefficient (ICC). RESULTS: Compared to the extended SEGUE scale total scores before the programme, the scores both immediately after and 1 month after the program increased significantly (15.88 ± 1.93 vs. 26.40 ± 1.47 and 26.15 ± 1.36, respectively, p < 0.001). The scores of five of the six dimensions in the extended SEGUE scale significantly increased (p < 0.001), except for the patient's perspective dimension score, which had no change (p = 0.162). With respect to this dimension, a subgroup analysis by gender indicated an increase among females (p < 0.001) and a decrease among males (p < 0.001). The VAS scores, which were evaluated for the SPs and trainees, increased significantly compared to the scores before the program, both immediately after and 1 month after the programme (4.31 ± 1.35 vs. 7.36 ± 1.62 and 7.34 ± 1.24, p < 0.001; 7.31 ± 1.25 vs. 8.39 ± 1.32 and 8.30 ± 1.24, p < 0.001, respectively). The consistency of the VAS between the SPs and surgical residents was 0.26 (p < 0.001), 0.70 (p < 0.001), and 0.70 (p < 0.001) before, immediately after and 1 month after the programme, respectively. CONCLUSION: This training programme improved the DPC competency of surgical residents, effectively increased the levels of satisfaction of both SPs and surgical residents, and improved the consistency of evaluation between SPs and surgical residents during doctor-patient encounters. The registration UIN is ChiCTR1800019790 from November 28, 2018.

Ultrahigh-reflective optical thin films prepared by reactive magnetron sputtering with RF-induced substrate bias.

Optical thin films with high-reflectivity (HR) are essential for applications in quantum precision measurements. In this work, we propose a coating technique based on reactive magnetron sputtering with RF-induced substrate bias to fabricate HR-optical thin films. First, atomically flat SiO2 and Ta2O5 layers have been demonstrated due to the assistance of radio-frequency plasma during the coating process. Second, a distributed Bragg reflector (DBR) mirror with an HR of ∼99.999 328% centered at 1397 nm has been realized. The DBR structure is air-H{LH}19-substrate, in which the L and H denote a single layer of SiO2 with a thickness of 237.8 nm and a single layer of Ta2O5 with a thickness of 171.6 nm, respectively. This novel coating method would facilitate the development of HR reflectors and promote their wide applications in precision measurements.

Revealing mechanism and influence of microalgae cells' periodical auto-agglomeration induced by high concentration of carbon dioxide.

The efficient cultivation of microalgae using CO2 from flue gas can be a win-win situation for both environmental protection and energy accessibility. In general, 10-20% of CO2 in flue gas would decrease pH and inhibit microalgae growth. However, Chlorella sorokiniana MB-1 under 15% CO2 showed a periodical auto-agglomeration, which promoted microalgae growth on the contrary in this study. The maximum biomass concentration of 3.27 g L-1 was higher than that cultivated with an optimal CO2 concentration. The pH decreased to 6.04 after the mixed gas with 15% CO2 (v/v) was bubbled into medium for 0.5 h, which resulted in auto-agglomeration to protect microalgae from acidification and keep a high specific growth rate of 0.03 h-1. Then the pH recovered to 7 during stabilization phase, auto-agglomeration ratio was up to 100% because of lamellar extracellular polymeric substances. Therefore, the interesting periodical agglomeration both enhanced growth and simplified harvesting.

How can vanillin improve the performance of lignocellulosic biomass conversion in an immobilized laccase microreactor system?

Gentle and effective pretreatment is necessary to produce clean lignocellulosic biomass-based fuels. Herein, inspired by the efficient lignin degradation in the foregut of termites, the microreactor system using immobilized laccase and recoverable vanillin was proposed. Firstly, the co-deposition coating of dopamine, hydrogen peroxide and copper sulfate was constructed for laccase immobilization and a high immobilization efficiency of 87.0% was obtained in 30 min. After storage for 10 days, 82.2% activity was maintained in the laccase-loaded microreactor, which is 210.0% higher than free laccase. In addition, 6% (w/w) vanillin can improve lignin degradation in the laccase-loaded microreactor without impairing laccase activity, leading to a 47.3% increment in cellulose accessibility. Finally, a high cellulose conversion rate of 88.1% can be achieved in 1 h with glucose productivity of 2.62 g L-1 h-1. These demonstrated that the appropriate addition of vanillin can synergize with immobilized laccase to enhance the conversion of lignocellulosic biomass.

Non-immersed zigzag microalgae biofilm overcoming high turbidity and ammonia of wastewater for muti-pollutants bio-purification.

Biological treatment that utilizes microalgae technology has demonstrated outstanding efficacy in the wastewater purification and nutrients recovery. However, the high turbidity of the digested piggery wastewater (DPW) leads to serious light attenuation and the culture mode of suspended microalgae results in a huge landing area. Thus, to overcome light attenuation in DPW, a non-immersed titled zigzag microalgae biofilm was constructed by attaching it onto a porous cotton cloth. As a result, the light could directly irradiate microalgae biofilm that attached on both sides of the cotton cloth, and the microalgal biofilm area was up to 6 m2 per bioreactor landing area. When the non-immersed zigzag microalgae biofilm bioreactor (N-Z-MBP) was used to treat wastewater with an ammonia nitrogen (NH4+-N) concentration of 362 mg L-1, the NH4+-N was completely removed in just 5 days and the maximum growth rate of microalgae biofilm reached 7.02 g m-2 d-1. After 21 days of long-term sequencing batch operation for the N-Z-MBP, the biomass density of the biofilm reached 52 g m-2 and remained at this high value for the next 14 days. Most importantly, during the 35 days' running, the NH4+ -N maximum removal rate of single batch reached up to 65 mg L-1 d-1 and its concentration in the effluent was always below the discharge standard value (80 mg L-1 form GB18596-2001 of China) and total phosphorus was completely removed in each batch. Furthermore, the biomass concentration of microalgae cells in the effluent of the N-Z-MBP was almost zero, indicating that the non-submerged biofilm achieved in situ separation of microalgae from the wastewater. This work suggests that the N-Z-MBP can effectively purify DPW over a long period, providing a possible strategy to treat wastewater with high ammonia nitrogen and high turbidity.

Photoenzymatic decarboxylation: A promising way to produce sustainable aviation fuels and fine chemicals.

As one of the fastest-growing carbon emission sources, the aviation sector is severely restricted by carbon emission reduction targets. Sustainable aviation fuel (SAF) has emerged as the most potential alternative to traditional aviation fuel, but harsh production technologies limit its commercialization. Fatty acids photodecarboxylase from Chlorella variabilis NC64A (CvFAP), the latest discovered photoenzyme, provides promising approaches to produce various carbon-neutral biofuels and fine chemicals. This review highlights the state-of-the-art strategies to enhance the application of CvFAP in carbon-neutral biofuel and fine chemicals production, including supplementing alkane as decoy molecular, screening efficient CvFAP variants with directed evolution, constructing genetic strains, employing biphasic catalytic system, and immobilizing CvFAP in an efficient photobioreactor. Furthermore, future opportunities are suggested to enhance photoenzymatic decarboxylation and explore the catalytic mechanism of CvFAP. This review provides a broad context to improve CvFAP catalysis and advance its potential applications.

Immobilization of fatty acid photodecarboxylase in magnetic nickel ferrite nanoparticle.

Fatty acid photodecarboxylase in Chlorella variabilis NC64A (CvFAP) performed excellent ability to exclusively decarboxylate renewable fatty acids for C1-shortened hydrocarbons fuel production under visible light. However, the large-scale application by such an approach is limited by the free state of CvFAP catalyst, which is unstable for efficient biofuel production. In this study, CvFAP was immobilized in magnetic nickel ferrite (NiFe2O4) nanoparticles for facile recovery by a simple procedure. The shift of Ni 2p in electron binding energy was detected to clarify the interaction between Ni2+ and histidine of CvFAP. The coordination of NiFe2O4 and CvFAP contributed to an efficient affinity binding with an immobilization capacity of 98 mg/g carrier. Hydrocarbon fuel concentration of 3.7 mM was obtained by NiFe2O4@CvFAP-induced photoenzymatic decarboxylation. The high stability of CvFAP in terms of residual enzyme activity of 79.7% at pH 9.0 and that of 68% at organic solvent ratio of 60%, respectively, were observed.