Fermented Soybean Paste Attenuates Biogenic Amine-Induced Liver Damage in Obese Mice.

Biogenic amines are cellular components produced by the decarboxylation of amino acids; however, excessive biogenic amine production causes adverse health problems. The relationship between hepatic damage and biogenic amine levels in nonalcoholic fatty liver disease (NAFLD) remains unclear. In this study, mice were fed a high-fat diet (HFD) for 10 weeks to induce obesity, presenting early-stage of NAFLD. We administered histamine (20 mg/kg) + tyramine (100 mg/kg) via oral gavage for 6 days to mice with HFD-induced early-stage NAFLD. The results showed that combined histamine and tyramine administration increased cleaved PARP-1 and IL-1ß in the liver, as well as MAO-A, total MAO, CRP, and AST/ALT levels. In contrast, the survival rate decreased in HFD-induced NAFLD mice. Treatment with manufactured or traditional fermented soybean paste decreased biogenically elevated hepatic cleaved PARP-1 and IL-1ß expression and blood plasma MAO-A, CRP, and AST/ALT levels in HFD-induced NAFLD mice. Additionally, the biogenic amine-induced reduction in survival rate was alleviated by fermented soybean paste in HFD-induced NAFLD mice. These results show that biogenic amine-induced liver damage can be exacerbated by obesity and may adversely affect life conservation. However, fermented soybean paste can reduce biogenic amine-induced liver damage in NAFLD mice. These results suggest a beneficial effect of fermented soybean paste on biogenic amine-induced liver damage and provide a new research perspective on the relationship between biogenic amines and obesity.

Evaluating the efficacy of slow-releasing carbon source tablets for in situ biological heterotrophic denitrification of groundwater.

Slow-releasing precipitating tablets (SRPTs) and slow-releasing floating tablets (SRFTs) were formulated to release fumarate as a carbon source (CS) and/or electron donor (ED) in an in situ biological heterotrophic denitrification system. These tablets were prepared using pharmaceutical manufacturing. Soil column tests were conducted to evaluate nitrate denitrification efficacy, microbial population changes, and mass balance of fumarate and potential electron acceptors. Significant and simultaneous consumption of both fumarate and nitrate, and the production and consumption of nitrite were observed in both SRPT-treated and SRFT-treated soil columns. These results suggest that SRPT and SRFT releasing fumarate, induce heterotrophic biological denitrification. In the SRPT- and SRFT-treated columns, 65% and 73% of fumarate were associated with heterotrophic denitrification, respectively. Particularly, surplus citric acid, originally designed to serve as a floating agent, was utilized for 36% and 28% for SRFT flotation and denitrification, respectively. The results of 16s RNA analyses revealed that a bacterium that shared 99% 16s rRNA sequence similarity with those of Azoarcus sp. AN9, and Pseudogulbenkiania sp. NH8B, a facultative heterotrophic denitrifier, was detected in the column effluent. This study confirms that SRPT and SRFT can effectively operate long-term in situ biological denitrification processes, because it is possible to supply detailed CS and/or ED uniformly by applying both SRPT and SRFT in the well.

Site-Directed Mutagenic Engineering of a Bifidobacterium Amylosucrase toward Greater Efficiency of Turanose Synthesis.

The aim of this study was to establish one of the most efficient biocatalytic processes for turanose production by applying a robust Bifidobacterium thermophilum (BtAS) mutant developed through site-directed mutagenesis. A gene encoding the amylosucrase of B. thermophilum (BtAS) was cloned and used as a mutagenesis template. Among the BtAS variants generated by the site-directed point mutation, four different single-point mutants (P200R, V202I, Y265F, and Y414F) were selected to create double-point mutants, among which BtASY414F/P200R displayed the greatest turanose productivity without losing the thermostability of native BtAS. The turanose yield of BtASY414F/P200R reached 89.3% at 50 °C after 6 h with 1.0 M sucrose + 1.0 M fructose. BtASY414F/P200R produced significantly more turanose than BtAS-wild type (WT) by 2 times and completed the reaction faster by another 2 times. Thus, turanose productivity (82.0 g/(L h)) by BtASY414F/P200R was highly improved from 28.1 g/(L h) of BtAS-WT with 2.0 M sucrose + 0.75 M fructose.

Development of a colorimetric enzymatic assay method for aromatic biogenic monoamine-producing decarboxylases.

Biogenic amines (BAs) produced by the action of bacterial amino acid decarboxylases in fermented foods cause various health problems in human. Despite the importance, detailed characterizations of the BA-producing decarboxylases are relatively less progressed than the studies on BA-producing bacteria, due to the time-consuming chromatography-based assay method. In this study, a simple and general colorimetric assay for aromatic amino acid decarboxylases coupled with an amine oxidase from Arthrobacter aurescens (AMAO) and horseradish peroxidase was developed using a tyrosine decarboxylase from Enterococcus faecium DSM20477 (EfmTDC) as a model enzyme. The activity profiles over pH and temperature and the kinetic analysis for EfmTDC revealed that the results by the colorimetric assay are compatible with those by the chromatographic assay. In addition, due to the broad substrate specificity of AMAO for histamine and 2-phenylethylamine, the colorimetric assay would be applicable to the characterization of other aromatic amino acid decarboxylases including histidine decarboxylases. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00938-4.

Effects of pH and NaCl on hydrolysis and transpeptidation activities of a salt-tolerant γ-glutamyltranspeptidase from Bacillus amyloliquefaciens S0904.

Bacillus amyloliquefaciens S0904 was selected as a hyperproducer of a glutamine-hydrolyzing enzyme which was identified as a γ-glutamyltranspeptidase catalyzing both hydrolysis and transpeptidation of glutamyl substrates. The signal peptide-truncated recombinant enzyme (rBAGGT) showed two-fold enhanced specific activity for hydrolysis and optimum pH shift to pH 7 from pH 6 compared with the wild type. The hydrolysis activity of rBAGGT was tolerant against NaCl up to 2.5 M, whereas the transpeptidation activity decreased by NaCl. At pH 6, the addition of 1.5 M NaCl not only enhanced the hydrolysis activity but also inhibited the transpeptidation activity to be ignorable. By contrast, at pH 9 in the absence of NaCl, the alkaline pH-favored transpeptidation activity was 99% of the maximum with only 15% of the maximum hydrolysis activity. In conclusion, the hydrolysis and transpeptidation activities of the recombinant BAGGT is controllable by changing pH and whether or not to add NaCl. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10068-021-00928-6.

Solid Fat Replacement with Canola Oil-Carnauba Wax Oleogels for Dairy-Free Imitation Cheese Low in Saturated Fat.

Canola oil was structured into oleogels with different amounts of carnauba wax, and their processing performances were assessed as an alternative to solid fat for imitation cheese low in saturated fat. The contents of solid fat in the oleogels were less vulnerable to the change in temperature than the palm oil. The replacement of palm oil with oleogels produced cheese samples with harder and more cohesive/chewy textures. Dynamic and transient viscoelastic measurements demonstrated that the use of oleogels was effective in increasing the elastic nature of the cheeses. Two distinct components with different proton mobilities were observed in the imitation cheeses, and longer T2 relaxation times were detected in the oleogel samples. The meltability of the cheese with palm oil was not significantly different from those with 3% and 6% oleogels. The saturated fat level of the oleogel cheese was significantly reduced from 45.70 to 5.20%. The application of canola oil-carnauba wax oleogels could successfully produce imitation cheese high in unsaturated fat and low in saturated fat. This study thus demonstrated that the health-functional properties of imitation cheese could be enhanced by using oleogels.

Finding new indicators for operation and angiographic embolization in blunt renal injury patients: a single-center experience over 13 years.

PURPOSE: Traumatic kidney injury can be treated surgically or nonsurgically. Nonsurgical treatment options include angiography, embolization, and conservative treatment. We aimed to identify factors that help in making clinical decisions on treatment plans for patients with traumatic kidney injury caused by blunt trauma. METHODS: The study included 377 patients aged ≥18 years with traumatic kidney injury caused by blunt abdominal trauma admitted to the emergency room of Wonju Severance Christian Hospital between January 2008 and July 2020. Medical records, laboratory test results, and computed tomography results were retrospectively reviewed. RESULTS: Multivariable logistic analysis showed diastolic blood pressure at admission and disruption of Gerota's fascia were significantly associated with surgical treatment, and that perinephric hematoma rim distance was the only significant indicator favoring embolization. Receiver operating characteristic curve analysis showed that angiography and embolization should be considered when hematoma size exceeds 2.97 cm. CONCLUSION: When a patient with traumatic kidney injury due to blunt trauma visits an emergency room, even when vital signs are stable, Gerota's fascia should be checked by computed tomography prior to deciding on surgical treatment, and angiographic embolization should be considered if perinephric hematoma rim distance exceeds 2.97 cm.

pH-promoted O-α-glucosylation of flavonoids using an engineered α-glucosidase mutant.

Retaining glycosidase mutants lacking its general acid/base catalytic residue are originally termed thioglycoligases which synthesize thio-linked disaccharides using sugar acceptor bearing a nucleophilic thiol group. A few thioglycoligases derived from retaining α-glycosidases have been classified into a new class of catalysts, O-glycoligases which transfer sugar moiety to a hydroxy group of sugar acceptors, resulting in the formation of O-linked glycosides or oligosaccharides. In this study, an efficient O-α-glucosylation of flavonoids was developed using an O-α-glycoligase derived from a thermostable α-glucosidase from Sulfolobus solfataricus (MalA-D416A). The O-glycoligase exhibited efficient transglycosylation activity with a broad substrate spectrum for all kinds of tested flavonoids including flavone, flavonol, flavanone, flavanonol, flavanol and isoflavone classes in yields of higher than 90%. The glucosylation by MalA-D416A preferred alkaline conditions, suggesting that pH-promoted deprotonation of hydroxyl groups of the flavonoids would accelerate turnover of covalent enzyme intermediate via transglucosylation. More importantly, the glucosylation of flavonoids by MalA-D416A was exclusively regioselective, resulting in the synthesis of flavonoid 7-O-α-glucosides as the sole product. Kinetic analysis and molecular dynamics simulations provided insights into the acceptor specificity and the regiospecificity of O-α-glucosylation by MalA-D416A. This pH promoted transglycosylation using O-α-glycoligases may prove to be a general synthesis route to flavonoid O-α-glycosides.

Assessing the feasibility of sequential aerobic respiration and heterotrophic denitrification of a high-strength mixture of phenol and its derivatives in the field single-well-drift test.

Biological degradation of high strength phenol and its derivatives in groundwater is problematic because these compounds are toxic to human and microbes. To evaluate the feasibility of in situ bioremediation using sequential aerobic respiration and heterotrophic denitrification, a field single-well-drift test (SWDT) was conducted in groundwater contaminated with coal tar distillates. To stimulate indigenous phenol degrading microorganisms, a 1400 L of oxygen-saturated test solution containing bromide (3.96 ±â€¯0.179 mmol-Br/L) and nitrate (5.34 ±â€¯0.187 mmol NO3--N/L) was injected into an aquifer. After injection of the test solution, significant consumption of dissolved oxygen (DO) was immediately observed; then, degradation of the methyl derivatives o-cresol and m,p-cresol was observed with average zero-order rate coefficients of 0.047 mmol/L/d and 0.23 mmol/L/d, respectively. After 73% of the injected DO was consumed, significant NO3- consumption was observed along with degradation of phenol and the dimethyl derivatives 2,4-xylenol and 3,5-xylenol, which had average zero-order rate coefficients of 0.17 mmol/L/d, 0.060 mmol/L/d, and 0.018 mmol/L/d, respectively. The production of CO2, NO2-, and N2O along with significant consumption of DO and NO3- suggest that phenolic compounds were biologically degraded by sequential aerobic respiration and heterotrophic denitrification. The results of 16s RNA analysis revealed that, after injection of the test solution, a bacterium that shared a 99% 16s rRNA sequence similarity with an uncultured bacterium revealed to be Pseudomonas stutzeri, a facultative heterotrophic denitrifier, was found in the aquifer. Thus, these results suggest that simultaneous injection of DO and NO3- is an appropriate in situ bioremediation strategy for degrading mixtures of high-strength phenolic compounds in an aquifer.

Effects of Calcium and Manganese on Sporulation of Bacillus Species Involved in Food Poisoning and Spoilage.

Spores are resistant against many extreme conditions including the disinfection and sterilization methods used in the food industry. Selective prevention of sporulation of Bacillus species is an ongoing challenge for food scientists and fermentation technologists. This study was conducted to evaluate the effects of single and combined supplementation of calcium and manganese on sporulation of common pathogenic and food spoilage Bacillus species: B. cereus, B. licheniformis, B. subtilis and B. coagulans. Sporulation of Bacillus vegetative cells was induced on sporulation media supplemented with diverse concentrations of the minerals. Under the various mineral supplementation conditions, the degree of sporulation was quantified with colonies formed by the Bacillus spores. The results revealed that B. licheniformis and B. cereus displayed the weakest sporulation capabilities on media with minimal supplementation levels of calcium and manganese. The lowest sporulation of B. subtilis and B. coagulans was observed on media supplemented with the highest level of calcium and low levels of manganese. Depending on effect of supplementation on sporulation, the Bacillus species were divided into two distinct groups: B. licheniformis and B. cereus; and B. subtilis and B. coagulans. The information provides valuable insight to selectively reduce sporulation of Bacillus species undesirable in the food industry.

Plasmonic bacteria on a nanoporous mirror via hydrodynamic trapping for rapid identification of waterborne pathogens.

A rapid, precise method for identifying waterborne pathogens is critically needed for effective disinfection and better treatment. However, conventional methods, such as culture-based counting, generally suffer from slow detection times and low sensitivities. Here, we developed a rapid detection method for tracing waterborne pathogens by an innovative optofluidic platform, a plasmonic bacteria on a nanoporous mirror, that allows effective hydrodynamic cell trapping, enrichment of pathogens, and optical signal amplifications. We designed and simulated the integrated optofluidic platform to maximize the enrichment of the bacteria and to align bacteria on the nanopores and plasmonic mirror via hydrodynamic cell trapping. Gold nanoparticles are self-assembled to form antenna arrays on the surface of bacteria, such as Escherichia coli and Pseudomonas aeruginosa, by replacing citrate with hydroxylamine hydrochloride in order to amplify the signal of the plasmonic optical array. Owing to the synergistic contributions of focused light via the nanopore geometry, self-assembled nanoplasmonic optical antennas on the surface of bacteria, and plasmonic mirror, we obtain a sensitivity of detecting E. coli as low as 102 cells/ml via surface-enhanced Raman spectroscopy. We believe that our label-free strategy via an integrated optofluidic platform will pave the way for the rapid, precise identification of various pathogens.

Tyramine reduction by tyrosine decarboxylase inhibitor in Enterococcus faecium for tyramine controlled cheonggukjang.

This study was carried out to find a method to control tyrosine decarboxylase activity (TDC) of a strain of Enterococcus faecium capable of producing high levels of tyramine. To select a TDC inhibitor, enzyme assay was first performed using purified TDC enzyme and 0.1% of TDC inhibiting chemicals. When 0.23% of nicotinic acid was added, tyramine content (363 ug/mL) was lower than that of the control group (873 ug/mL). At the same time, bacterial growth was decreased 1 log cycle from 8.62 to 7.56 log CFU/mL. TDC expression level in E. faecium was measured by using RT-qPCR. Lower expression level (below 0.7) was observed after the addition of 0.23% nicotinic acid (in vitro). When cheonggukjang was manufactured with addition of nicotinic acid, tyramine contents were decreased from 698.67 to 117.27 mg/kg when the concentration of nicotinic acid added was increased from 0.10 to 0.30%. These results suggest that nicotinic acid could be used as an agent (TDC inhibitor) to reduce tyramine content in cheonggukjang.

The American Society of Anesthesiologists score influences on postoperative complications and total hospital charges after laparoscopic colorectal cancer surgery.

The aim of this study was to investigate the influence of American Society of Anesthesiologists (ASA) scores on postoperative complication rates and total hospital charges following laparoscopic surgery for colorectal cancer.All patients (n = 664) underwent laparoscopic colorectal cancer surgery. A group of patients with an ASA score of 1 or 2 (n = 575) and a group of patients with an ASA score of 3 (n = 89) were compared.The mean age was higher in the group of patients with an ASA score of 3 than in the group of patients with an ASA score of 1 or 2 (70 vs 67 years). The rate of ICU admission (27% vs 15%) was higher in the ASA score 3 group. The mean hospital stay (14 vs 12 days) was longer in the ASA score 3 group. Postoperative 30-day complications (38% vs 27%), 30-day mortality (2% vs 0%), and a Clavien-Dindo classification of ≥3 (21% vs 11%) occurred more frequently in the ASA score 3 group. Mean total hospital charges were significantly higher in the ASA score 3 group (13,906 vs 11,575 USD). Independent risk factors that affected postoperative complications were older age [≥80 years, hazard ratio (HR) = 2.8], an ASA score of 3 (HR = 1.6), and the presence of a primary rectal tumor (HR = 1.6). Postoperative complication rates were 21.9%, 28.5%, and 38.2% in the ASA score 1, 2, and 3 groups, respectively. Total hospital charges were 14,376 USD and 10,877 USD in the groups with and without postoperative complications, respectively. Mean total hospital charges were 10,769 USD, 11,756 USD, and 13,906 USD in the ASA score 1, 2, and 3 groups, respectively.Preoperative ASA scores may be a predictor of postoperative complications and hospital costs when planning laparoscopic surgery for colorectal cancer.

Activated STAT3 may participate in tumor progression through increasing CD133/survivin expression in early stage of colon cancer.

The activation of signal transducer and activator of transcription 3 (STAT3) by elevated interleukin (IL) levels has been reported to regulate tumorigenesis both in vitro and in vivo. However, the clinical implication of p-STAT3 expression in colon cancer is still controversial. In this study, we evaluated the effect of STAT3 inactivation on biologic behavior of primary (Caco-2) and metastatic colon cancer cells (LoVo and SNU407) and the relation of p-STAT3 expression with the invasion of colon tumor. In vitro study, the STAT3 inhibition by siRNA and stattic treatment significantly reduced colony formation and cell migration and decreased CD133 and survivin the expression compared with a control in all three cell lines. Furthermore, primary cancer cells exhibited a marked decrease in CD133 expression and increased apoptosis compared to metastatic cells after stattic treatment. The immunohistochemical assay using clinical samples of colonic tumors with various invasion depth showed that p-STAT3 expression was inversely associated with tumor invasion (p = 0.001, hazard ratio (HR) = 0.328, 95% confidence interval (95%CI): 0.170-0.632). In conclusion, p-STAT3 may participate in the progression of the early stage of colon cancer through the up-regulation of CD133, which in turn induces survivin expression. However, the regulatory mechanism of these molecules in tumor progression in vivo is need to be more verified.

Differences Regarding the Molecular Features and Gut Microbiota Between Right and Left Colon Cancer.

For many years, developmental and physiological differences have been known to exist between anatomic segments of the colorectum. Because of different outcomes, prognoses, and clinical responses to chemotherapy, the distinction between right colon cancer (RCC) and left colon cancer (LCC) has gained attention. Furthermore, variations in the molecular features and gut microbiota between right and LCCs have recently been a hot research topic. CpG island methylator phenotype-high, microsatellite instability-high colorectal cancers are more likely to occur on the right side whereas tumors with chromosomal instability have been detected in approximately 75% of LCC patients and 30% of RCC patients. The mutation rates of oncogenes and tumor suppressor genes also differ between RCC and LCC patients. Biofilm is more abundant in RCC patients than LLC patients, as are Prevotella, Selenomonas, and Peptostreptococcus. Conversely, Fusobacterium, Escherichia/Shigella, and Leptotrichia are more abundant in LCC patients compared to RCC patients. Distinctive characteristics are apparent in terms of molecular features and gut microbiota between right and LCC. However, how or to what extent these differences influence diverging oncologic outcomes remains unclear. Further clinical and translational studies are needed to elucidate the causative relationship between primary tumor location and prognosis.

Differences in clinical features and oncologic outcomes between metastatic right and left colon cancer.

Approximately 20% to 25% of patients with colorectal cancer (CRC) have distant organ metastasis at the time of initial diagnosis. The primary tumor location has been suggested as a prognostic factor for patients with metastatic CRC. In recent years, the distinction between right colon cancer (RCC) and left colon cancer (LCC) has been brought into focus due to their different outcomes, prognoses, and clinical responses to chemotherapy. In this article we aimed to review the underlying differences between metastatic RCC and LCC in terms of epidemiology, clinical features, and oncologic outcomes. The outcomes of patients with left-sided tumors were better than those of patients with right-sided tumors in terms of overall survival (OS) and objective response rate (ORR) after treatment with chemotherapy + panitumumab in the PRIME and 20050181 trials. The outcomes of patients with LCC were better than those of patients with RCC in terms of OS, progression-free survival (PFS) and ORR after treatment with FOLFIRI + cetuximab in the CRYSTAL and CALGB 80405 trials. In the FIRE-3 trial, the OS and PFS, but not the ORR, of patients with LCC were superior to those of patients with RCC. LCC and RCC exhibit distinctive clinical features and epidemiology. However, we must further investigate the impact of these distinctive features and how they influence the differential oncologic outcomes.

Comparison of the Short-Term Outcomes of Laparoscopic and Open Resections for Colorectal Cancer in Patients with a History of Prior Median Laparotomy.

This study aimed to investigate the short-term outcomes of laparoscopic resection in comparison with those of open resection for colorectal cancer in patients with a history of prior median laparotomy (PML). Eighty-seven consecutive patients (87/1121, 7.8 %) with a history of PML who underwent major colorectal cancer resection were enrolled (laparoscopy, n = 40; open, n = 47). The conversion rate to open surgery was 25 % (n = 10). The laparoscopy group had a higher proportion of female patients (57.5 vs. 36.2 %), a lower rate of American Society of Anesthesiologists (ASA) score for physical status of ≥3 (7.5 vs. 25.5 %), and a lower pT4 tumor rate (15 vs. 38.3 %) than the open resection group. Regarding the reasons for PML, radical hysterectomy with extended lymphadenectomy for gynecologic cancer was more common (32.5 vs. 4.3 %), but gastrointestinal surgeries, such as gastrectomy and colectomy, were less frequent in the laparoscopy group. Regarding intraoperative outcomes, the laparoscopy group showed a similar operative time (197 vs. 204 min), intraoperative enterotomy rate (2.5 vs. 2.1 %), and bowel resection rate (2.5 vs. 2.1 %) with the open resection group. Regarding postoperative outcomes, the laparoscopy group showed a lower complication rate (20 vs. 40.4 %), significantly reduced time to soft diet (5 vs. 7 days), and shorter hospital stay (12 vs. 18 days). Despite the high rate of open conversion, favorable short-term outcomes were observed in the laparoscopic group. Laparoscopy may be chosen as the primary approach in selected patients with a history of non-gastrointestinal PML (prior abdominal surgery for gynecological cancer).

The impact of delayed commencement of adjuvant chemotherapy (eight or more weeks) on survival in stage II and III colon cancer: a national population-based cohort study.

BACKGROUND: To examine the impact of chemotherapy delay on survival in patients with stage II or III colon cancer and the factors associated with the delay (≥8 weeks) of adjuvant chemotherapy. METHODS: Patients undergoing curative resection and adjuvant chemotherapy in a national population-based cohort were included. RESULTS: Among 5355 patients, 154 (2.9%) received chemotherapy more than 8 weeks after surgery. Based on a multivariate analysis, the risk factors associated with chemotherapy delay ≥8 weeks were older age [65 to 74 years (hazard ratio [HR]=1.48) and ≥75 years (HR=1.69), p=0.0354], medical aid status in the health security system (HR=1.76, p=0.0345), and emergency surgery (HR=2.43, p=0.0002). Using an 8-week cutoff, the 3-year overall survival rate was 89.62% and 80.98% in the <8 weeks and ≥8 weeks groups, respectively (p=0.008). Independent prognostic factors for inferior overall survival included chemotherapy delay ≥8 weeks (HR=1.49, p=0.0365), older age [65 to 74 years (HR=1.94) and ≥75 years (HR=3.41), p<0.0001], TNM stage III (HR=2.46, p<0.0001), emergency surgery (HR=1.89, p<0.0001), American Society of Anesthesiologists score of 3 or higher (HR=1.50, p<0.0001), and higher transfusion amounts (HR=1.09, p=0.0392). CONCLUSIONS: This study shows that delayed commencement of adjuvant chemotherapy, defined as ≥ 8 weeks, is associated with inferior overall survival in colon cancer patients with stage II or III disease. The delay to initiation of adjuvant chemotherapy is influenced by several multidimensional factors, including patient factors (older age), insurance status (medical aid), and treatment-related factors (emergency surgery).

Physicochemical interactions of cycloamylose with phenolic compounds.

The complex formation capability of cycloamylose (CA), having a degree of polymerization of 23-45, with phenolic compounds (PCs) was investigated using various physicochemical techniques. The fluorescence intensity of PCs increased and then reached a plateau at 10-20mM cyclodextrin, while it continued to increase at up to 60mM CA. Thermodynamic data of CA complexes with PCs revealed that the binding process was primarily enthalpy-driven and spontaneous. CA favored to form the most stable complex with chlorogenic acid (CHA) among all PCs. Chemical shift changes for the protons in interior and exterior of CA, as well as in PCs suggested a possible formation of both inclusion and extramolecular interactions between CA and PCs. The ROESY spectrum confirmed that the aromatic moieties of CHA were partially interacted with CA molecules through relatively weak binding. XRD, DSC, and SEM results also supported the complex formation by intermolecular interaction between CA and CHA.