Structure modeling-based characterization of ChnD, the 6-hydroxyhexanoate dehydrogenase from Acinetobacter sp. strain NCIMB 9871.

α,ω-Dicarboxylic acids, ω-aminoalkanoic acids, and α,ω-diaminoalkanes are valuable building blocks for the production of biopolyesters and biopolyamides. One of the key steps in producing these chemicals is the oxidation of ω-hydroxycarboxylic acids using alcohol dehydrogenases (e.g., ChnD of Acinetobacter sp. NCIMB 9871). However, the reaction and structural features of these enzymes remain mostly undiscovered. Thereby, we have investigated characteristics of ChnD based on enzyme kinetics, substrate-docking simulations, and mutation studies. Kinetic analysis revealed a distinct preference of ChnD for medium chain ω-hydroxycarboxylic acids, with the highest catalytic efficiency of 18.0 mM-1s-1 for 12-hydroxydodecanoic acid among C6 to C12 ω-hydroxycarboxylic acids. The high catalytic efficiency was attributed to the positive interactions between the carboxyl group of the substrates and the guanidino group of two arginine residues (i.e., Arg62 and Arg266) in the substrate binding site. The ChnD_R62L variant showed the increased efficiency and affinity, particularly for fatty alcohols (i.e., C6-C10) and branched-chain fatty alcohols, such as 3-methyl-2-buten-1-ol. Overall, this study contributes to the deeper understanding of medium-chain primary aliphatic alcohol dehydrogenases and their applications for the production of industrially relevant chemicals such as α,ω-dicarboxylic acids, ω-aminoalkanoic acids, and α,ω-diaminoalkanes from renewable biomass.

Initial Development of User-Based Quality Evaluation Questionnaire of Smartwatch Technology for Applying to Healthcare.

Background: Smartwatches are a consumer wearable device offering a potential, practical, and affordable method to collect personal health data in healthy adults. For patients with chronic diseases, this would enable symptom monitoring and aid clinical decision making. Therefore, providing customized checklists to recommend smartwatches is beneficial. However, few studies have evaluated the practical functions of smartwatches and their influence on user acceptance. We aimed at developing a reliable tool to assess the quality of smartwatches from the users' perspective. Methods: To develop the smartwatch rating scale (SWRS), we conducted a comprehensive literature review as well as reviewed relevant websites. The SWRS includes 22 items for the usability (usability, functionality, safety, material, and display) and five items for the acceptance and adoption domain (satisfaction and intention). We measured the scale's internal consistency and inter-rater reliability by evaluating seven smartwatches. Results: The overall scale demonstrated an excellent level of internal consistency (Cronbach's alpha = 0.91), with each subscale's internal consistency above good level (0.74 ~ 0.92). Inter-rater reliability using intraclass correlation coefficients (ICC) was at good level (2-way random ICC = 0.82, 95% CI 0.09 - 0.97). Conclusions: The SWRS is reliable, which can meet the need for assessment of smartwatch technology for utilizing in personal healthcare. Accounting for users' perspectives will help make the most of technology without impairing the human aspects of care, this study can help consumers choose a smartwatch based on their preferences and provide guidelines for developing user-friendly wearable devices aimed at health behavior changes.

Association of sleep duration and physical frailty with cognitive function in older patients with coexisting atrial fibrillation and heart failure.

AIM: To investigate the associations of sleep duration and physical frailty with cognitive function in older patients with both atrial fibrillation and heart failure. DESIGN: This study used a cross-sectional, secondary data analysis design. METHOD: We included outpatients aged ≥ 65 years with coexisting atrial fibrillation and heart failure in South Korea. We used a sample of 176 patients (men = 100) with HF among 277 data from the parent study. The data were collected through a self-report, structured questionnaire and electronic medical record. RESULTS: Our main finding showed that long sleep duration and physically frail status were significant predictors of cognitive impairment in older adults with both atrial fibrillation and heart failure. Healthcare providers should be aware of the importance of assessing sleep duration and physical activity in older adults with both atrial fibrillation and heart failure to prevent or delay cognitive impairment.

The Prevalence of Cognitive Frailty and Its Association with Sleep duration and Depression Among Older Adults with Heart Failure.

OBJECTIVES: The prevalence of cognitive frailty and its associated factors in older population with heart failure have not been extensively studied. We investigated the prevalence of cognitive frailty and its association with sleep duration and depression among older adults with heart failure. METHODS: This secondary analysis used a cross-sectional sample with 168 older adults with heart failure from an academic tertiary care hospital in South Korea. RESULTS: Cognitive frailty was found in 58 (34.5%) older adults with heart failure. Our main finding revealed that longer sleep durations of ≥ 8 h (adjusted odds ratio (OR) = 2.62, 95% confidence interval (CI) = 1.04-6.59) and depression (adjusted OR = 2.84, 95% CI = 1.22-6.61) predicted an increased risk of cognitive frailty. CONCLUSIONS: Early detection on changes in sleep patterns and depression can play a crucial role in reducing the risk of cognitive frailty in patients with heart failure. Longitudinal studies are needed to explore that sleep patterns and depression are both linked to greater risk of developing cognitive frailty among older adults with heart failure. CLINICAL IMPLICATIONS: Development of a validated instrument for cognitive frailty screening may be beneficial for older adults with heart failure to prevent adverse outcomes.

Triplet-triplet annihilation-based photon-upconversion to broaden the wavelength spectrum for photobiocatalysis.

Photobiocatalysis is a growing field of biocatalysis. Especially light-driven enzyme catalysis has contributed significantly to expanding the scope of synthetic organic chemistry. However, photoenzymes usually utilise a rather narrow wavelength range of visible (sun)light. Triplet-triplet annihilation-based upconversion (TTA-UC) of long wavelength light to shorter wavelength light may broaden the wavelength range. To demonstrate the feasibility of light upconversion we prepared TTA-UC poly(styrene) (PS) nanoparticles doped with platinum(II) octaethylporphyrin (PtOEP) photosensitizer and 9,10-diphenylanthracene (DPA) annihilator (PtOEP:DPA@PS) for application in aqueous solutions. Photoexcitation of PtOEP:DPA@PS nanoparticles with 550 nm light led to upconverted emission of DPA 418 nm. The TTA-UC emission could photoactivate flavin-dependent photodecarboxylases with a high energy transfer efficiency. This allowed the photodecarboxylase from Chlorella variabilis NC64A to catalyse the decarboxylation of fatty acids into long chain secondary alcohols under green light (λ = 550 nm).

Perioperative risk factors for new-onset postoperative atrial fibrillation among patients after isolated coronary artery bypass grafting: A retrospective study.

AIMS: Incidence of atrial fibrillation is considerably high after open heart surgery, which may prolong hospitalization and increase mortality. The aim of the present study is to investigate the perioperative risk factors for the occurrence of new-onset atrial fibrillation following isolated coronary artery bypass grafting. DESIGN: A retrospective study. METHODS: A total of 327 Korean patients recorded to have undergone first-time isolated coronary artery bypass grafting and no preoperative history of atrial fibrillation were included. The data were obtained from electronic health record from January 2010 to December 2019 at a tertiary care hospital. Predictors of new-onset atrial fibrillation after the surgery were identified by multivariate logistic regression analysis. RESULTS: The incidence rate of new-onset atrial fibrillation after coronary artery bypass grafting was approximately 28.4%, and the highest occurrence rate was 44.1% on postoperative day 2. Our main finding showed that advanced age was the strongest predictor of atrial fibrillation after coronary artery bypass grafting. In addition, history of stroke and depression, chronic obstructive pulmonary disease and intraoperative use of intra-aortic balloon pump were shown to be the risk factors. CONCLUSION: Our findings showed that approximately 28% patients had new-onset atrial fibrillation after the surgery. Healthcare professionals should proactively assess risk factors for postoperative atrial fibrillation and focus more on older adults with pre-existing comorbidities, such as stroke, depression and chronic obstructive pulmonary disease. IMPACT: Older adults with history of stroke, depression and comorbid chronic obstructive pulmonary disease should be carefully monitored closely during perioperative period. The study highlights that early assessment of new-onset postoperative atrial fibrillation can contribute to promote the quality of nursing care and frontline nurses may be a vital role in timely detection of atrial fibrillation after surgery. Prospective studies are required to identify the mechanisms connecting perioperative risk factors for atrial fibrillation after cardiac surgery.

Perioperative risk factors for new-onset postoperative atrial fibrillation after coronary artery bypass grafting: a systematic review.

BACKGROUND: Postoperative atrial fibrillation (POAF) is the most common cardiac dysrhythmia to occur after coronary artery bypass grafting (CABG). However, the risk factors for new-onset POAF after CABG during the perioperative period have yet to be clearly defined. Accordingly, the aim of our systematic review was to evaluate the perioperative predictors of new-onset POAF after isolated CABG. METHOD: Our review methods adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. We searched seven electronic databases (PubMed, Embase, CINAHL, PsycArticles, Cochrane, Web of Science, and SCOPUS) to identify all relevant English articles published up to January 2020. Identified studies were screened independently by two researchers for selection, according to predefined criteria. The Newcastle-Ottawa Scale was used to evaluate the quality of studies retained. RESULTS: After screening, nine studies were retained for analysis, including 4798 patients, of whom 1555 (32.4%) experienced new-onset POAF after CABG. The incidence rate of new-onset POAF ranged between 17.3% and 47.4%. The following risk factors were identified: old age (p < 0.001), a high preoperative serum creatinine level (p = 0.001), a low preoperative hemoglobin level (p = 0.007), a low left ventricle ejection fraction in Asian patients (p = 0.001), essential hypertension (p < 0.001), chronic obstructive pulmonary disease (p = 0.010), renal failure (p = 0.009), cardiopulmonary bypass use (p = 0.002), perfusion time (p = 0.017), postoperative use of inotropes (p < 0.001), postoperative renal failure (p = 0.001), and re-operation (p = 0.005). All studies included in the analysis were of good quality. CONCLUSIONS: The risk factors identified in our review could be used to improve monitoring of at-risk patients for early detection and treatment of new-onset POAF after CABG, reducing the risk of other complications and negative clinical outcomes.

Incidence and Risk Factors of Cardio-Cerebrovascular Disease in Korean Menopausal Women: A Retrospective Observational Study using the Korean Genome and Epidemiology Study data.

PURPOSE: Cardio-cerebrovascular diseases constitute the most common and fatal disease among menopausal women. However, the risk of cardio-cerebrovascular diseases in menopausal women compared to men has been underestimated, with insufficient related studies. Therefore, we examined the incidence and risk factors of cardio-cerebrovascular diseases among Korean menopausal women. METHODS: A retrospective observational study design with secondary analysis was conducted using data from the Korean Genome and Epidemiology Study survey. We used the study's data of 1,197 menopausal women, aged 40-64 years, who did not have cardio-cerebrovascular diseases at baseline and their related data from the biennial follow-ups over 14 years. Cardio-cerebrovascular diseases were defined as hypertension, coronary artery disease, or stroke. The incidence of cardio-cerebrovascular diseases was calculated per person-years, and multivariate Cox proportional hazards models were used to determine the predictors of cardio-cerebrovascular diseases during the follow-up period. RESULTS: Of the 1,197 cases, 264 were early or surgical menopausal women. The overall incidence of cardio-cerebrovascular diseases was 18.75 per 1,000 person-years. Early or surgical menopause (HR = 4.32, p < .001), along with family history of cardiovascular disease (HR = 1.87, p = .024), elevated blood pressure (HR = 1.79, p < .001), abdominal obesity (HR = 1.37, p = .046), or duration of menopause at the same age (HR = 1.01, p = .001), were strong predictors of cardio-cerebrovascular diseases. CONCLUSION: Based on the results of this study, it is necessary to identify and closely monitor women with early or surgical menopause for cardiovascular and cerebrovascular diseases prevention. Also, prevention of cardio-cerebrovascular diseases through blood pressure and abdominal obesity management is vital for menopausal women.

Predictors of unplanned 30-day readmissions after coronary artery bypass graft: a systematic review and meta-analysis of cohort studies.

AIMS: Coronary artery bypass graft (CABG) is one of the most performed cardiac surgery globally. CABG is known to have a high rate of short-term readmissions. The 30-day unplanned readmission rate as a quality measure is associated with adverse health outcomes. This study aimed to identify and synthesize the perioperative risk factors for 30-day unplanned readmission after CABG. METHODS AND RESULTS: We systematically searched seven databases and reviewed studies to identify all eligible English articles published from 1 October 1999 to 30 September 2019. Random-effect models were employed to perform pooled analyses. Odds ratio and 95% confidence interval were used to estimate the risk factors for 30-day unplanned readmission. The 30-day hospital readmission rates after CABG ranged from 9.2% to 18.9% in 14 cohort studies. Among preoperative characteristics, older adults, female, weight loss, high serum creatinine, anticoagulant use or dialysis, and comorbidities were found to be statistically significant. Postoperative complications, prolonged length of hospital stay, and mechanical ventilation were revealed as the postoperative risk factors for 30-day unplanned readmission. However, intraoperative risk factors were not found to be significant in this review. CONCLUSION: Our findings emphasize the importance of a comprehensive assessment during the perioperative period of CABG. Healthcare professionals can perform a readmission risk stratification and develop strategies to reduce readmission rates after CABG using the risk factors identified in this review. Future studies with prospective cohort samples are needed to identify the personal or psychosocial factors influencing readmission after CABG, including perioperative risk factors.

Impact of Hospital Nurses' Perception on Clinical Alarms and Patient Safety Culture on Alarm Management Practice.

This study aimed to identify the impact of nurses' perception of clinical alarms and patient safety culture on alarm management. Additionally, we aimed to describe the importance of clinical alarm issues. The data were collected from 21 August to 10 September 2020. The study participants were 116 nurses working in a tertiary acute care hospital in Korea. The self-report questionnaire included general characteristics, clinical alarm issues, nurses' alarm perception, patient safety culture, and alarm management practice. The mean age of nurses was 28.04 ± 4.06 years, with 5.71 ± 4.35 years of total clinical experience. For the importance of alarm issues, frequent false alarms leading to reduced attention or response was the most important issue. Hierarchical linear regression analysis revealed that a higher level of nurses' perceived patient safety culture was the strongest predictor of better alarm management practice (p < 0.001), followed by their perception of clinical alarms (p = 0.034). In addition, female nurses (p = 0.004), charge nurses (p = 0.013), and nurses who work less than 40 h per week (p = 0.008) were more likely to work better in alarm management practice. Future studies are needed to develop standardized alarm management guidelines by improving nurses' positive perceptions of clinical alarms and patient safety culture.

Gender Differences Regarding the Impact of Change in Cognitive Function on the Functional Status of Intensive Care Unit Survivors: A Prospective Cohort Study.

PURPOSE: This study aimed to identify gender differences with regard to the impact of change in cognitive function on functional status 3 months after receiving critical care. DESIGN AND METHODS: This prospective cohort study investigated 152 intensive care unit (ICU) patients. Their functional status and cognitive function were assessed using the validated Korean version of the Modified Barthel Index and Mini-Mental State Examination, respectively. Hierarchical regression was used to evaluate the impact of change in cognitive function on functional status in ICU survivors by gender. FINDINGS: The proportion of women suffering from consistent cognitive impairment was significantly higher than that of men. Women had a rate of improvement to normal cognitive function within 3 months after discharge that was higher than that of men. Functional status 3 months after discharge was significantly lower for patients whose cognitive impairment was consistent than that for those whose cognitive function was normal. The impact of change in cognitive function on men (R2 change = .28) was greater than that on women (R2 change = .13). CONCLUSIONS: Persistent cognitive impairment after critical illness had a negative effect on functional status in ICU survivors. Importantly, the negative impact of consistent cognitive impairment was greater in men than in women. CLINICAL RELEVANCE: Early careful assessment of functional and cognitive status after critical illness is warranted. Strategies addressing the gender-specific characteristics related to cognitive improvement should also be developed.

The moderating role of acculturation mode on the relationship between depressive symptoms and health-related quality of life among international students in Korea.

We examined the moderating role of acculturation mode on the relationship between depressive symptoms and health-related quality of life (HRQoL) in international students. This cross-sectional study enrolled a convenience sample of 147 international students at a university in Korea. Participants' overall HRQoL was moderate (mean = 57.2 of 80). The main and interaction effects of depressive symptoms and selected acculturation modes explained 39.9% of the variance in HRQoL. For all acculturation modes except the integration mode, as depressive symptom scores increased, HRQoL decreased. Specifically, at high depressive symptoms levels, participants with the marginalization, separation, and assimilation modes had worse HRQoL than did the integration mode, while HRQoL was similar for all acculturation modes at low depressive symptom levels. These findings suggest that future prospective intervention strategies should be considered for not only depressive symptoms levels, but also for different acculturation modes to enhance HRQoL in this population.

Cofactor specificity engineering of a long-chain secondary alcohol dehydrogenase from Micrococcus luteus for redox-neutral biotransformation of fatty acids.

Structure-based engineering of a NAD+-dependent secondary alcohol dehydrogenase from Micrococcus luteus led to a 1800-fold increase in catalytic efficiency for NADP+. Furthermore, the engineered enzymes (e.g., D37S/A38R/V39S/T15I) were successfully coupled to a NADPH-dependent Baeyer-Villiger monooxygenase from Pseudomonas putida KT2440 for redox-neutral biotransformations of C18 fatty acids into C9 chemicals.

Multi-Step Enzymatic Synthesis of 1,9-Nonanedioic Acid from a Renewable Fatty Acid and Its Application for the Enzymatic Production of Biopolyesters.

1,9-Nonanedioic acid is one of the valuable building blocks for producing polyesters and polyamides. Thereby, whole-cell biosynthesis of 1,9-nonanedioic acid from oleic acid has been investigated. A recombinant Corynebacterium glutamicum, expressing the alcohol/aldehyde dehydrogenases (ChnDE) of Acinetobacter sp. NCIMB 9871, was constructed and used for the production of 1,9-nonanedioic acid from 9-hydroxynonanoic acid, which had been produced from oleic acid. When 9-hydroxynonanoic acid was added to a concentration of 20 mM in the reaction medium, 1,9-nonanedioic acid was produced to 16 mM within 8 h by the recombinant C. glutamicum. The dicarboxylic acid was isolated via crystallization and then used for the production of biopolyester by a lipase. For instance, the polyesterification of 1,9-nonanedioic acid and 1,8-octanediol in diphenyl ether by the immobilized lipase B from Candida antarctica led to formation of the polymer product with the number-average molecular weight (Mn) of approximately 21,000. Thereby, this study will contribute to biological synthesis of long chain dicarboxylic acids and their application for the enzymatic production of long chain biopolyesters.

Relationship between the frequency of nursing activities and adverse outcomes in patients with acute coronary syndrome: A retrospective cohort study.

The aim of this retrospective cohort study was to identify the relationship between the frequency of nursing activities during the first hospitalization and adverse outcomes in patients with acute coronary syndrome by using electronic health records. Patients diagnosed with acute coronary syndrome from April 2010 to April 2015 were examined for eligibility based on 36 months of major adverse cardiac events as the main outcome. Among the 652 patients who were enrolled, 66 patients experienced major adverse cardiac events. The average frequency of nursing activities was 1098.7 (±2703.8), and four variables (length of hospital stay, albumin level, hemoglobin level, and frequency of nursing activities) were significantly associated with 36 months of major adverse cardiac events. After adjusting for these variables, the frequency of nursing activities was found to be the only significant factor associated with the incidence of 36 months of major adverse cardiac events. This finding suggests that patients with acute coronary syndrome who require more frequent nursing activities during the first hospitalization could be vulnerable to adverse outcomes and should be closely monitored.

Health-Related Quality of Life and Associated Factors in Patients with Atrial Fibrillation: An Integrative Literature Review.

Atrial fibrillation (AF) is a common cardiac arrhythmia associated with poor health-related quality of life (HRQoL). However, the factors influencing HRQoL in patients with AF are not well understood. The purpose of integrative review was to investigate the factors affecting HRQoL in patients with AF based on the six domains of Ferrans and colleagues' HRQoL model. A total of 23 relevant articles published between January 2000 and March 2018 were identified using four databases and analyzed in this study. Our review showed that the HRQoL in patients with AF was consistently lower than both healthy individuals and patients with other cardiovascular diseases. The most common factor associated with HRQoL in patients with AF was anxiety-specific to AF in the symptoms domain, followed by frequency and severity of symptoms and the New York Heart Association functional class. This study highlights that monitoring and assessing patients' symptoms is vital for improving HRQoL in patients with AF. Disease-specific and cross-culturally validated tools can allow healthcare professionals to provide tailored interventions for patients with AF.

Multi-level engineering of Baeyer-Villiger monooxygenase-based Escherichia coli biocatalysts for the production of C9 chemicals from oleic acid.

Whole-cell biotransformation is one of the promising alternative approaches to microbial fermentation for producing high-value chemicals. Baeyer-Villiger monooxygenase (BVMO)-based Escherichia coli biocatalysts have been engineered to produce industrially relevant C9 chemicals, such as n-nonanoic acid and 9-hydroxynonanoic acid, from a renewable long-chain fatty acid. The key enzyme in the biotransformation pathway (i.e., BVMO from Pseudomonans putida KT2440) was first engineered, using structure modeling-based design, to improve oxidative and thermal stabilities. Using a stable and tunable plasmid (STAPL) system, E. coli host cells were engineered to have increased plasmid stability and homogeneity of the recombinant E. coli population, as well as to optimize the level of BVMO expression. Multi-level engineering of the key enzyme in host cells, allowed recombinant E. coli expressing a fatty acid double-bond hydratase, a long-chain secondary alcohol dehydrogenase, and the engineered BVMO from P. putida KT2440 (i.e., E6BVMO_C302L/M340L), to ultimately produce C9 chemicals (i.e., n-nonanoic acid and 9-hydroxynonanoic acid) from oleic acid, with a yield of up to 6 mmoL/g dry cells. This yield was 2.4-fold greater than the yield in the control strain before engineering. Therefore, this study will contribute to the development of improved processes for the biosynthesis of industrially relevant medium chain fatty acids via whole-cell biocatalysis.

Health Literacy but Not Frailty Predict Self-Care Behaviors in Patients with Heart Failure.

Heart failure (HF) is a chronic condition requiring continuous self-care. Health literacy is increasingly recognized as a key factor of self-care behaviors in patients with chronic diseases. Recently, frailty in chronic diseases has also been associated with self-care behaviors. However, relationships among health literacy, frailty, and self-care in the HF population are not well understood. Therefore, this cross-sectional study aimed to identify the impact of health literacy and frailty on self-care behaviors in patients with HF. Data were collected from 281 adults attending a cardiovascular outpatient clinic in Korea. Health literacy, frailty, and self-care behaviors were measured using Korean-validated instruments. The mean scores of health literacy and self-care behaviors were 8.89 (±3.44) and 31.49 (±5.38), respectively. The prevalence of frailty was around 26.3%. Health literacy was significantly associated with frailty and self-care behaviors. In a hierarchical linear regression analysis, health literacy was a significant determinant of self-care behaviors after adjusting for confounding variables, but frailty was not. Educational level was also a significant predictor of self-care behaviors. Our main findings showed that health literacy can facilitate improvements in HF self-care behaviors. Healthcare professionals should assess patients' health literacy and educational backgrounds when designing self-management programs.

The Association Between Perceived Stress and Quality of Life in University Students: The Parallel Mediating Role of Depressive Symptoms and Health-Promoting Behaviors.

PURPOSE: This study examined whether depressive symptoms and health-promoting lifestyle behaviors mediate the association between perceived stress and quality of life (QoL) in university students. METHODS: Using a cross-sectional survey, Korean university students (N = 187, Mage = 23.97 years; 54.0% Woman) completed structured questionnaires with psychometric adequacy. A parallel multiple mediation model was used to test the mediating effect of depressive symptoms and health-promoting lifestyle behaviors on the relationship between perceived stress and QoL. RESULTS: Total effect of perceived stress, depressive symptoms, and health-promoting lifestyle behaviors on QoL was -.55. Of these, total indirect mediating effect was -.50, whereas direct effect was only -.05 in the parallel mediation model. In particular, depressive symptoms (indirect effect = -.32) and health-promoting lifestyle behaviors (indirect effect = -.18) completely mediated the relationship between perceived stress and QoL. CONCLUSION: The results suggest that effective strategies primarily focusing on improving depressive symptoms along with health behaviors are needed to decrease the negative effect of perceived stress on QoL.

Improving catalytic activity of the Baeyer-Villiger monooxygenase-based Escherichia coli biocatalysts for the overproduction of (Z)-11-(heptanoyloxy)undec-9-enoic acid from ricinoleic acid.

Baeyer-Villiger monooxygenases (BVMOs) can be used for the biosynthesis of lactones and esters from ketones. However, the BVMO-based biocatalysts are not so stable under process conditions. Thereby, this study focused on enhancing stability of the BVMO-based biocatalysts. The biotransformation of ricinoleic acid into (Z)-11-(heptanoyloxy)undec-9-enoic acid by the recombinant Escherichia coli expressing the BVMO from Pseudomonas putida and an alcohol dehydrogenase from Micrococcus luteus was used as a model system. After thorough investigation of the key factors to influence stability of the BVMO, Cys302 was identified as an engineering target. The substitution of Cys302 to Leu enabled the engineered enzyme (i.e., E6BVMOC302L) to become more stable toward oxidative and thermal stresses. The catalytic activity of E6BVMOC302L-based E. coli biocatalysts was also greater than the E6BVMO-based biocatalysts. Another factor to influence biocatalytic performance of the BVMO-based whole-cell biocatalysts was availability of carbon and energy source during biotransformations. Glucose feeding into the reaction medium led to a marked increase of final product concentrations. Overall, the bioprocess engineering to improve metabolic stability of host cells in addition to the BVMO engineering allowed us to produce (Z)-11-(heptanoyloxy)undec-9-enoic acid to a concentration of 132 mM (41 g/L) from 150 mM ricinoleic acid within 8 h.