Fermentation strategy for the production of poly(3-hydroxyhexanoate) by Aeromonas sp. KC014

Ho-Shing Wu,Yen-An Gong,Yu-Hong Wei,Yi-Ming Sun 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.6

Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(3HB-co-3HHx)) was produced by Aeromonas sp. KC014 strain isolated from Taiwan in soil environment in the flask and fermentor cultures. The medium optimization, such as carbon source and nitrogen source, carbon-nitrogen ratio was conducted to obtain the optimum 3-hydroxyhexanoate content. The defined medium with dodecanoic acid as the carbon source and (NH4)2SO4 as the nitrogen source was obtained as the main medium. When cells grown in medium containing 30 g/L dodecanoic acid, 15 g/L sodium gluconate and 1 g/L soytone (C/N was 30/1) as final PHA concentration, the cell dry weight and HB content of 5.16 g/ L, 14.0 g/L and 36.0%, respectively, were obtained. The maximum HHx/PHA content increased from 0.1% to 1.3% nearly 12-fold when the dissolved oxygen was decreased from 40% to 20%. P(3HB-co-3HHx) biosynthesis was triggered by the addition of limited nitrogen, phosphorus and magnesium to get a maximum HHx/PHA content of 14% in 95 hours.

Diagnosis of Seronegative Rheumatoid Arthritis by 68 Ga-FAPI PET/CT

Shing Kee Cheung,Sirong Chen,Yuet Hung Wong,Kwan Kit Wu,Chi Lai Ho 대한핵의학회 2023 핵의학 분자영상 Vol.57 No.1

Early diagnosis of rheumatoid arthritis with the initiation of disease-modifying antirheumatic drugs is important to preventfuture disability. Seronegative rheumatoid arthritis lacks the classical immunological markers, thus imposing clinical diagnosticdifficulty. In this case, we reported 68 Ga-FAPI PET/CT findings of seronegative rheumatoid arthritis in a 60-year-oldlady. This case illustrates how 68 Ga-FAPI PET/CT aids in the diagnosis of seronegative rheumatoid arthritis.

Comparison of Serum Ketone Levels and Cardiometabolic Efficacy of Dapagliflozin versus Sitagliptin among Insulin-Treated Chinese Patients with Type 2 Diabetes Mellitus

Chi-Ho Lee,Mei-Zhen Wu,David Tak-Wai Lui,Darren Shing-Hei Chan,Carol Ho-Yi Fong,Sammy Wing-Ming Shiu,Ying Wong,Alan Chun-Hong Lee,Joanne King-Yan Lam,Yu-Cho Woo,Karen Siu-Ling Lam,Kelvin Kai-Hang Yiu 대한당뇨병학회 2022 Diabetes and Metabolism Journal Vol.46 No.6

Background: Insulin-treated patients with long duration of type 2 diabetes mellitus (T2DM) are at increased risk of ketoacidosis related to sodium-glucose co-transporter 2 inhibitor (SGLT2i). The extent of circulating ketone elevation in these patients remains unknown. We conducted this study to compare the serum ketone response between dapagliflozin, an SGLT2i, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, among insulin-treated T2DM patients.Methods: This was a randomized, open-label, active comparator-controlled study involving 60 insulin-treated T2DM patients. Participants were randomized 1:1 for 24-week of dapagliflozin 10 mg daily or sitagliptin 100 mg daily. Serum β-hydroxybutyrate (BHB) levels were measured at baseline, 12 and 24 weeks after intervention. Comprehensive cardiometabolic assessments were performed with measurements of high-density lipoprotein cholesterol (HDL-C) cholesterol efflux capacity (CEC), vibration-controlled transient elastography and echocardiography.Results: Among these 60 insulin-treated participants (mean age 58.8 years, diabetes duration 18.2 years, glycosylated hemoglobin 8.87%), as compared with sitagliptin, serum BHB levels increased significantly after 24 weeks of dapagliflozin (P=0.045), with a median of 27% increase from baseline. Change in serum BHB levels correlated significantly with change in free fatty acid levels. Despite similar glucose lowering, dapagliflozin led to significant improvements in body weight (P=0.006), waist circumference (P=0.028), HDL-C (P=0.041), CEC (P=0.045), controlled attenuation parameter (P=0.007), and liver stiffness (P=0.022). Average E/e’, an echocardiographic index of left ventricular diastolic dysfunction, was also significantly lower at 24 weeks in participants treated with dapagliflozin (P=0.037).Conclusion: Among insulin-treated T2DM patients with long diabetes duration, compared to sitagliptin, dapagliflozin modestly increased ketone levels and was associated with cardiometabolic benefits.

Determination of Fungal Glucosamine Using HPLC with 1-napthyl Isothiocyanate Derivatization and Microwave Heating

Azis Boing Sitanggang,Ho-Shing Wu,Shaw S. Wang 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.6

A rapid method for the determination of fungal glucosamine (GlcN) from Aspergilus BCRC 31742 was developed. The hydrochlorination process using microwave effectively reduced reaction time needed for GlcN analysis. The analytical method consisted of two steps: (1) hydrochlorination of fungal cells and (2) derivatization process. Fungal GlcN hydrochloride was reacted with 1-napthyl isothiocyanate (1-NITC) as the derivatizing agent to enhance the sensitivity of GlcN and so to achieve high resolution. This method was specific for quantification of GlcN hydrochloride at the wavelength of 230 nm. The standard deviation and relative error of the analytical results were less than 5%. By using microwave heating, the reaction time of hydrochlorination process was shortened from 24 h to 3 min. Thus, the overall time needed for analyzing GlcN from fungal sources was reduced from 5 h (thermal method) to 2 h (microwave method). A rapid method for the determination of fungal glucosamine (GlcN) from Aspergilus BCRC 31742 was developed. The hydrochlorination process using microwave effectively reduced reaction time needed for GlcN analysis. The analytical method consisted of two steps: (1) hydrochlorination of fungal cells and (2) derivatization process. Fungal GlcN hydrochloride was reacted with 1-napthyl isothiocyanate (1-NITC) as the derivatizing agent to enhance the sensitivity of GlcN and so to achieve high resolution. This method was specific for quantification of GlcN hydrochloride at the wavelength of 230 nm. The standard deviation and relative error of the analytical results were less than 5%. By using microwave heating, the reaction time of hydrochlorination process was shortened from 24 h to 3 min. Thus, the overall time needed for analyzing GlcN from fungal sources was reduced from 5 h (thermal method) to 2 h (microwave method).

Direct Purification of Burkholderia Pseudomallei Lipase from Fermentation Broth Using Aqueous Two-Phase Systems

Chien Wei Ooi,Beng Ti Tey,Siew Ling Hii,Arbakariya Ariff,Ho Shing Wu,John Chi Wei Lan,Ruey Shin Juang,Siti Mazlina Mustapa Kamal,Tau Chuan Ling 한국생물공학회 2009 Biotechnology and Bioprocess Engineering Vol.14 No.6

An aqueous two-phase purification process was employed for the recovery of Burkholderia pseudomallei from fermentation broth. The partition behavior of B.pseudmallei lipase was investigated with various parameters such as phase composition, tie-line length (TLL), volume ratio (VR), sample loading, system pH, and addition of neutral salts. Optimum conditions for the purification of lipase were obtained in polyethylene glycol (PEG) 6000-potassium phosphate system using TLL of 42.2% (w/w), with VR of 2.70, and 1% (w/w) NaCl addition at pH 7 for 20% (w/w) crude load. Based on this system, the purification factor of lipase was enhanced to 12.42 fold, with a high yield of 93%. Hence, the simplicity and effectiveness of aqueous two-phase systems (ATPS) in the purification of lipase were proven in this study An aqueous two-phase purification process was employed for the recovery of Burkholderia pseudomallei from fermentation broth. The partition behavior of B.pseudmallei lipase was investigated with various parameters such as phase composition, tie-line length (TLL), volume ratio (VR), sample loading, system pH, and addition of neutral salts. Optimum conditions for the purification of lipase were obtained in polyethylene glycol (PEG) 6000-potassium phosphate system using TLL of 42.2% (w/w), with VR of 2.70, and 1% (w/w) NaCl addition at pH 7 for 20% (w/w) crude load. Based on this system, the purification factor of lipase was enhanced to 12.42 fold, with a high yield of 93%. Hence, the simplicity and effectiveness of aqueous two-phase systems (ATPS) in the purification of lipase were proven in this study