ABSTRACT
Isoamyl fatty acid esters (IAFEs) are widely used as fruity flavor compounds in the food industry. In this study, various IAFEs were synthesized from isoamyl alcohol and various fatty acids using a cutinase enzyme (Rcut) derived from Rhodococcus bacteria. Rcut was immobilized on methacrylate divinylbenzene beads and used to synthesize isoamyl acetate, butyrate, hexanoate, octanoate, and decanoate. Among them, Rcut synthesized isoamyl butyrate (IAB) most efficiently. Docking model studies showed that butyric acid was the most suitable substrate in terms of binding energy and distance from the active site serine (Ser114) γ-oxygen. Up to 250 mM of IAB was synthesized by adjusting reaction conditions such as substrate concentration, reaction temperature, and reaction time. When the enzyme reaction was performed by reusing the immobilized enzyme, the enzyme activity was maintained at least six times. These results demonstrate that the immobilized Rcut enzyme can be used in the food industry to synthesize a variety of fruity flavor compounds, including IAB.
Subject(s)
Carboxylic Ester Hydrolases , Enzymes, Immobilized , Flavoring Agents , Molecular Docking Simulation , Rhodococcus , Enzymes, Immobilized/metabolism , Enzymes, Immobilized/chemistry , Rhodococcus/enzymology , Rhodococcus/metabolism , Flavoring Agents/metabolism , Flavoring Agents/chemistry , Carboxylic Ester Hydrolases/metabolism , Carboxylic Ester Hydrolases/chemistry , Esters/metabolism , Esters/chemistry , Pentanols/metabolism , Pentanols/chemistry , Fatty Acids/metabolism , Fatty Acids/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/chemistry , Temperature , Substrate Specificity , Butyric Acid/metabolism , Butyric Acid/chemistry , Catalytic DomainABSTRACT
PURPOSE: This study aimed to analyze the treatment outcomes and adverse effects of moderately hypofractionated partial breast irradiation (PBI) in patients with early breast cancer. METHODS: In total, 473 patients with early breast cancer or carcinoma in situ were diagnosed with Tis or T1N0 disease and underwent PBI following breast-conserving surgery. All histologic tumor types, close surgical margins within 1 mm of the tumor, and multifocal tumors were included in this study. A radiation dose of 50 Gy in 20 fractions was delivered over 4 weeks using intensity-modulated radiotherapy technique. Dosimetric data, recurrence patterns, survival outcomes, and adverse events were retrospectively analyzed. RESULTS: During a median follow-up of 28.9 months, seven patients (1.5%) experienced ipsilateral breast tumor recurrence (IBTR). Two patients had regional recurrence, four patients developed contralateral breast cancer, and no distant metastases were observed. The locoregional recurrence rate in the ipsilateral breast was 1.8%. Two deaths occurred during the follow-up period, but were not attributed to breast cancer. The 2-year disease-free survival and 2-year overall survival rates were was 94.0% and 99.8%, respectively. Acute adverse events occurred in 131 patients (27.1%), and were distributed among all grades, with only two patients (0.4%) experiencing grade 3 events. Late adverse events were noted in 16 patients (3.4%), and were distributed among all grades, including grade 3 events in four patients (0.8%). No grade 4 or 5 events were observed. CONCLUSION: Hypofractionated PBI demonstrated favorable IBTR rates in patients with early breast cancer, with low incidence of acute and late toxicities in the short-term analysis.
ABSTRACT
BACKGROUND/PURPOSE: The eighth edition of the AJCC staging system introduced a shift in the staging of distal bile duct cancer (DBC), emphasizing the depth of invasion over adjacent organ invasion. This study aimed to evaluate the clinical impact of pancreatic invasion in pT1-stage DBC and identify prognostic factors for long-term survival. METHODS: This multicenter retrospective analysis encompassed DBC patients who underwent pancreaticoduodenectomy between 2009 and 2019 in six Korean tertiary centers, specifically those with final pathology confirming AJCC eighth edition T1 stage and intrapancreatic bile duct tumor origin. Primary endpoints were five-year recurrence-free survival (RFS) and overall survival (OS). Secondary objectives included the identification of prognostic determinants. RESULTS: This study involved 287 patients, comprising 190 without and 97 with pancreatic invasion. Pancreatic invasion did not significantly influence five-year OS and RFS rates (OS: without pancreatic invasion 69.9% vs. with pancreatic invasion 54.1%, p = .25; RFS: 56.3% vs. 55.4%, p = .97). Multivariate analysis highlighted male gender, age, lymphovascular invasion, and N stage as significant OS determinants. Notably, male gender, ampulla of Vater invasion, lymphovascular invasion, and N1 stage were also associated with RFS. CONCLUSIONS: In pT1 DBC, pancreatic invasion demonstrates no substantial impact on long-term prognosis, in accordance with the depth-based paradigm of the eighth edition AJCC staging system. The prognostic factors influencing OS were identified as male gender, age, lymphovascular invasion, and nodal metastasis.