Immobilized Candida antarctica lipase B as an sn-1,3 regiospecific biocatalyst for the interesterification of triacylglycerols with fatty acid ethyl esters.

Candida antarctica lipase B (CALB) is regarded as non-regiospecific. This study aimed to investigate the regiospecificity of CALB in the solvent-free interesterification of high-oleic sunflower oil with stearic acid ethyl ester for 1,3-distearoyl-2-oleoylglycerol (SOS)-rich fat preparation using a packed bed reactor. The content ratio of 1,2-distearoyl-3-oleoylglycerol (SSO) to SOS (denoted by SSO/SOS content) obtained using Lipozyme 435 (a commercially immobilized CALB; 0-4.1%), at residence times (1-32 min) was similar to that obtained using Lipozyme RM IM (0-3.0%), but lower than that obtained using Lipozyme TL IM (6.0-39.4%). When immobilized on Lewatit VP OC 1600, Lipozyme CALB had an SSO/SOS content of 0-10.4%, which was greater than that of Palatase 20,000 L (0-1.1%) but was lower than that of Lipozyme TL 100 L (8.8-97.7%). Our findings suggest that immobilized CALB shows distinct sn-1,3 regiospecificity in the interesterification of triacylglycerol with fatty acid ethyl esters.

7,10-Dihydroxy-8(E)-octadecenoic Acid Displays a Fungicidal Activity against Malassezia furfur.

Microbial conversion of some natural unsaturated fatty acids can produce polyhydroxy fatty acids, giving them new properties, such as higher viscosity and reactivity. Pseudomonas aeruginosa has been intensively studied to produce a novel 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) from oleic acid and natural vegetable oils containing oleic acid. Recently, the antibacterial activities of DOD against food-borne pathogenic bacteria were reported; however, the action of such antibacterial properties against eucaryotic cells remains poorly known. In this study, we determined the antifungal activities of DOD against Malassezia furfur KCCM 12679 quantitatively and qualitatively. The antifungal activity of DOD against M. furfur KCCM 12679 was approximately five times higher than that of ketoconazole, a commercial antifungal agent. The MIC 90 value of DOD against M. furfur KCCM 12679 was 50 µg/mL. In addition, we confirmed that the antifungal property of DOD was exerted through fungicidal activity.

Orthognathic surgical planning using graph CNN with dual embedding module: External validations with multi-hospital datasets.

BACKGROUND AND OBJECTIVE: Despite recent development of AI, prediction of the surgical movement in the maxilla and mandible by OGS might be more difficult than that of tooth movement by orthodontic treatment. To evaluate the prediction accuracy of the surgical movement using pairs of pre-(T0) and post-surgical (T1) lateral cephalograms (lat-ceph) of orthognathic surgery (OGS) patients and dual embedding module-graph convolution neural network (DEM-GCNN) model. METHODS: 599 pairs from 3 institutions were used as training, internal validation, and internal test sets and 201 pairs from other 6 institutions were used as external test set. DEM-GCNN model (IEM, learning the lat-ceph images; LTEM, learning the landmarks) was developed to predict the amount and direction of surgical movement of ANS and PNS in the maxilla and B-point and Md1crown in the mandible. The distance between T1 landmark coordinates actually moved by OGS (ground truth) and predicted by DEM-GCNN model and pre-existed CNN-based Model-C (learning the lat-ceph images) was compared. RESULTS: In both internal and external tests, DEM-GCNN did not exhibit significant difference from ground truth in all landmarks (ANS, PNS, B-point, Md1crown, all P > 0.05). When the accumulated successful detection rate for each landmark was compared, DEM-GCNN showed higher values than Model-C in both the internal and external tests. In violin plots exhibiting the error distribution of the prediction results, both internal and external tests showed that DEM-GCNN had significant performance improvement in PNS, ANS, B-point, Md1crown than Model-C. DEM-GCNN showed significantly lower prediction error values than Model-C (one-jaw surgery, B-point, Md1crown, all P < 0.005; two-jaw surgery, PNS, ANS, all P < 0.05; B point, Md1crown, all P < 0.005). CONCLUSION: We developed a robust OGS planning model with maximized generalizability despite diverse qualities of lat-cephs from 9 institutions.

Screening obstructive sleep apnea patients via deep learning of knowledge distillation in the lateral cephalogram.

The lateral cephalogram in orthodontics is a valuable screening tool on undetected obstructive sleep apnea (OSA), which can lead to consequences of severe systematic disease. We hypothesized that a deep learning-based classifier might be able to differentiate OSA as anatomical features in lateral cephalogram. Moreover, since the imaging devices used by each hospital could be different, there is a need to overcome modality difference of radiography. Therefore, we proposed a deep learning model with knowledge distillation to classify patients into OSA and non-OSA groups using the lateral cephalogram and to overcome modality differences simultaneously. Lateral cephalograms of 500 OSA patients and 498 non-OSA patients from two different devices were included. ResNet-50 and ResNet-50 with a feature-based knowledge distillation models were trained and their performances of classification were compared. Through the knowledge distillation, area under receiver operating characteristic curve analysis and gradient-weighted class activation mapping of knowledge distillation model exhibits high performance without being deceived by features caused by modality differences. By checking the probability values predicting OSA, an improvement in overcoming the modality differences was observed, which could be applied in the actual clinical situation.

Immune-Stimulating Potential of Lacticaseibacillus rhamnosus LM1019 in RAW 264.7 Cells and Immunosuppressed Mice Induced by Cyclophosphamide.

Probiotics, including Lacticaseibacillus rhamnosus (L. rhamnosus), have gained recognition for their potential health benefits, such as enhancing immune function, maintaining gut health, and improving nutrient absorption. This study investigated the effectiveness of L. rhamnosus LM1019 (LM1019) in enhancing immune function. In RAW 264.7 cells, LM1019 demonstrated dose-dependent immune stimulation by increasing nitric oxide production, gene expression of proinflammatory cytokines, and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). These effects were mediated through the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) translocation without inducing cytotoxicity. Furthermore, orally administered LM1019 was evaluated in immunosuppressed mice induced by cyclophosphamide (CTX). High-dose administration of LM1019 significantly increased the subpopulations of lymphocytes, specifically helper T cells (CD4+), as well as two subtypes of natural killer (NK) cells, namely, IFN-γ+ and granzyme B+ NK cells. Additionally, LM1019 at a high dose led to elevated levels of proinflammatory cytokines, including IFN-γ and IL-12, compared to CTX-treated mice. These findings highlight the potential of LM1019 in enhancing the immune system. The study contributes to the growing body of research on the beneficial effects of probiotics on immune function.

Lipase-catalyzed preparation of deacidified Buah Merah (Pandanus conoideus) oil.

Buah Merah oil (BMO) is unrefined edible oil containing a high level of free fatty acids (FFA; ∼30% w/w). This study was aimed at preparing deacidified BMO from BMO via lipase-catalyzed esterification of FFA in BMO with added glycerol, using Duolite A568-immobilized Eversa Transform 2.0 (Thermomyces lanuginosus lipase) as biocatalyst. BMO containing 2.4% w/w FFA and 94.6% w/w triacylglycerol was obtained under optimal reaction conditions (temperature, 70°C; FFA-to-glycerol molar ratio, 3:1; enzyme loading based on the protein quantity, 3.75 mg/g BMO, and reaction time, 48 h). No significant difference was found in the contents of ß-carotene, tocopherols, and phytosterols between raw and deacidified BMO. The induction period of oxidation was significantly longer in deacidified BMO (16.37 h) than in raw BMO (0.03 h). These results suggest that deacidified BMO could be enzymatically prepared without the loss of health-beneficial minor components while enhancing the oxidative stability. PRACTICAL APPLICATION: Although BMO has recently received much attention for its potential biological activities, the commercial use of BMO as a healthy oil has been limited due to its high FFA content. Unlike conventional alkali and steam refining, enzymatic deacidification of BMO employed in this study might help the commercialization of BMO, because this procedure enables the improvement of oil yield and the retaining of health-beneficial minor components.

Green Tea and Java Pepper Mixture Prevents Obesity by Increasing Energy Expenditure and Modulating Hepatic AMPK/MicroRNA-34a/370 Pathway in High-Fat Diet-Fed Rats.

This study was performed to evaluate the anti-obesity effects of green tea and java pepper mixture (GJ) on energy expenditure and understand the regulatory mechanisms of AMP-activated protein kinase (AMPK), microRNA (miR)-34a, and miR-370 pathways in the liver. Sprague-Dawley rats were divided into four groups depending on the following diets given for 14 weeks: normal chow diet (NR), 45% high-fat diet (HF), HF + 0.1% GJ (GJL), and HF + 0.2% GJ (GJH). The results revealed that GJ supplementation reduced body weight and hepatic fat accumulation, improved serum lipids, and increased energy expenditure. In the GJ-supplemented groups, the mRNA levels of genes related to fatty acid syntheses, such as a cluster of differentiation 36 (CD36), sterol regulatory element binding protein-1c (SREBP-1c), fatty acid synthase (FAS), and stearoyl-CoA desaturase 1 (SCD1) were downregulated, and mRNA levels of peroxisome proliferator-activated receptor alpha (PPARα), carnitine/palmitoyl-transferase 1 (CPT1), and uncoupling protein 2 (UCP2), which participate in fatty acid oxidation, were upregulated in the liver. GJ increased the AMPK activity and decreased the miR-34a and miR-370 expression. Therefore, GJ prevented obesity by increasing energy expenditure and regulating hepatic fatty acid synthesis and oxidation, suggesting that GJ is partially regulated through AMPK, miR-34a, and miR-370 pathways in the liver.

Efficient Synthesis of Stearidonic Acid Enriched Triacylglycerol from Ahiflower Seed Oil via a Two-Step Enzyme Reaction.

Stearidonic acid (SDA) is a plant-based n-3 polyunsaturated fatty acid with multiple biological activities. The enrichment of SDA and synthesis of triacylglycerol (TAG) were carried out consecutively via two lipase-catalyzed reactions, hydrolysis, and esterification. First, SDA was enriched into a glyceride fraction from ahiflower seed oil by Candida rugosa lipase-catalyzed hydrolysis. Under the optimum conditions of 35°C, 0.1% lipase powder of Lipase OF, and 50% buffer solution (based on the weight of total substrate), SDA was enriched from 21.6 to 40.7 wt% in glyceride fraction. SDA-enriched TAG was then synthesized from the SDA-enriched glyceride and the SDA-enriched fatty acid via esterification using an in-house immobilized lipase as a biocatalyst. The SDA-enriched fatty acid was obtained from part of the SDA-enriched glyceride by saponification and the in-house immobilized lipase was prepared from Eversa® Transform 2.0 using Lewatit VP OC 1600 as a carrier. The optimum reaction conditions for the synthesis of TAG were a temperature of 50°C, an enzyme loading of 10%, and a vacuum of 10 mmHg. A maximum conversion to TAG of ca. 94% was achieved after 12 h under the optimum conditions.

Enzymatic structural modification of monogalactosyldiacylglycerols for potential modulation of hydrophile-lipophile balance.

This study aimed to enzymatically prepare structured monogalactosyldiacylglycerols (MGDGs) with different hydrophile-lipophile balance (HLB) values for use as emulsifiers. Acidolysis of Perilla frutescens-derived MGDGs with capric acid (10:0) was conducted to obtain structured MGDGs containing 10:0. Lewatit VP OC 1600-immobilized Rhizomucor miehei lipase was used as the biocatalyst. Structured MGDGs (HLB value = 2.95-7.17) containing 13.0-70.6 mol% 10:0 were obtained from P. frutescens MGDGs (HLB value = 1.93). A quadratic regression equation (R2 = 0.920) to predict the 10:0 content of the structured MGDGs under the given conditions was established using response surface methodology. Using a linear regression equation (R2 = 0.999) to predict the HLB value by 10:0 content, structured MGDGs containing 27.1-54.6 mol% 10:0 were predicted to have an HLB value of 4-6, indicating their potential applicability as hydrophobic emulsifiers. Structured MGDGs with a purity of âˆ¼ 43% w/w were obtained from the reaction products using silica column chromatography.

Preparation of Low-Diacylglycerol Cocoa Butter Equivalents by Hexane Fractionation of Palm Stearin and Shea Butter.

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.

High hydrostatic pressure extract of mulberry leaves ameliorates hypercholesterolemia via modulating hepatic microRNA-33 expression and AMPK activity in high cholesterol diet fed rats.

BACKGROUND: Mulberry leaf (Morus alba L.) contains multiple bioactive ingredients and has been used in the treatment of obesity, diabetes, inflammation, and atherosclerosis. High hydrostatic pressure (HHP) processing has been developed for the extraction of bioactive compounds from plants. However, the hypocholesterolemic effect of the HHP extract from mulberry leaves and its underlying mechanism have never been investigated. OBJECTIVE: The specific aim of the present study was to investigate the hypocholesterolemic property of a novel extract obtained from mulberry leaves under HHP in rats. DESIGN: Sprague-Dawley rats were divided into four groups and fed either a normal diet (NOR), a high cholesterol diet containing 1% cholesterol and 0.5% cholic acid (HC), an HC diet containing 0.5% mulberry leaf extract (ML), or a 1% mulberry leaf extract (MH) for 4 weeks. RESULTS: High hydrostatic pressure extract of mulberry leaves significantly reduced the HC-increased serum levels of triglyceride (TG), cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), and hepatic contents of TG and TC. The HHP extraction from mulberry leaves also increased the HC-decreased fecal TC and bile acid levels without changing body weight, food intake, liver weight, and serum activities of alanine transaminase (ALT) and aspartate transaminase (AST) (P < 0.05). The mulberry leaf extract significantly enhanced the expression of hepatic genes such as cholesterol 7 alpha-hydroxylase (CYP7A1), liver X receptor alpha (LXRα), and ATP-binding cassette transporters, ABCG5/ABCG8, involved in hepatic bile acid synthesis and cholesterol efflux (P < 0.05). In addition, the HHP extraction of mulberry leaves significantly suppressed hepatic microRNA(miR)-33 expression and increased adenosine monophosphate-activated protein kinase (AMPK) activity. CONCLUSION: These results suggest that the HHP extract of mulberry leaves lowers serum cholesterol levels by partially increasing hepatic bile acid synthesis and fecal cholesterol excretion through the modulation of miR-33 expression and AMPK activation in the liver.

Comparing intra-observer variation and external variations of a fully automated cephalometric analysis with a cascade convolutional neural net.

The quality of cephalometric analysis depends on the accuracy of the delineating landmarks in orthodontic and maxillofacial surgery. Due to the extensive number of landmarks, each analysis costs orthodontists considerable time per patient, leading to fatigue and inter- and intra-observer variabilities. Therefore, we proposed a fully automated cephalometry analysis with a cascade convolutional neural net (CNN). One thousand cephalometric x-ray images (2 k × 3 k) pixel were used. The dataset was split into training, validation, and test sets as 8:1:1. The 43 landmarks from each image were identified by an expert orthodontist. To evaluate intra-observer variabilities, 28 images from the dataset were randomly selected and measured again by the same orthodontist. To improve accuracy, a cascade CNN consisting of two steps was used for transfer learning. In the first step, the regions of interest (ROIs) were predicted by RetinaNet. In the second step, U-Net detected the precise landmarks in the ROIs. The average error of ROI detection alone was 1.55 ± 2.17 mm. The model with the cascade CNN showed an average error of 0.79 ± 0.91 mm (paired t-test, p = 0.0015). The orthodontist's average error of reproducibility was 0.80 ± 0.79 mm. An accurate and fully automated cephalometric analysis was successfully developed and evaluated.

Detection of Circulating Gastrointestinal Cancer Cells in Conditionally Reprogrammed Cell Culture.

BACKGROUND/AIM: The aim of this study was to detect circulating tumor cells (CTC) in the peripheral blood of gastrointestinal cancer patients using conditionally reprogrammed cell (CRC) culture. MATERIALS AND METHODS: We confirmed the sensitivity of the CRC culture method. Five ml of blood were obtained from 81 cancer patients (56 colorectal and 25 gastric). The collected mononuclear cells were cultured for 4 weeks in the CRC condition. Finally, cultured cells were characterized by RT-PCR for the expression of hTERT and MAGE A1-6 mRNA. RESULTS: The CRC method had a CTC detection limit of 6 cells for gastric cancer cells. After culture of 81 blood specimens, 38 formed visible cells, including 5 colonies. Among the 38 cells, 13 were hTERT positive and 4 were MAGE A1-6 positive. The final CTC detection rate was 16.0%. CONCLUSION: The CRC culture may potentially be used to evaluate the metastatic cancer cells in the circulation.

Isolation and compositional analysis of galactoglycerolipids from perilla [Perilla frutescens (L.) Britton] leaves and comparison to the galactoglycerolipids from spinach and parsley.

The aim of this study was to isolate monogalactosyldiacylglycerols (MGDGs) and digalactosyldiacylglycerols (DGDGs) from perilla [Perilla frutescens (L.) Britton] and to investigate their fatty acid profiles. Perilla displayed the greatest total MGDG and DGDG content among the three types of leaf vegetables tested, that is, spinach, parsley, and perilla, containing 0.16 g/100 g MGDG and 0.04 g/100 g DGDG (on wet weight basis). High purity MGDG (approximately 97 g/100 g) and DGDG (approximately 86 g/100 g) were isolated from perilla chloroform/methanol (2:1, v/v) extracts by two-step silica gel column chromatography. MGDGs were primarily composed of 18:3n-3 and 16:3n-3, predominantly located at the sn-1 and sn-2 positions, respectively. In DGDG, 18:3n-3 and 16:0 were the most abundant fatty acids and were primarily found at the sn-1 and sn-2 positions, respectively. PRACTICAL APPLICATION: MGDGs and DGDGs are the most prevalent forms of galactoglycerolipids found in leaf vegetables including perilla and have been shown to exert health-beneficial effects, such as antitumor, anti-inflammatory, anticancer, and appetite-suppressing activities. Both MGDGs and DGDGs possess emulsifying properties. The present study may help better understand the health-beneficial effects of MGDG and DGDG from perilla, by providing total composition and positional distribution of the fatty acids. The present study also successfully established a protocol to isolate high purity MGDG and DGDG from perilla, thereby increasing their possible use as an ingredient in foods and nutraceuticals.

Immobilized Phospholipase A1-Catalyzed Preparation of l-α-Glycerylphosphorylcholine from Phosphatidylcholine.

This study sought to prepare a cognitive enhancer l-α-glycerylphosphorylcholine (l-α-GPC) using an immobilized Lecitase Ultra (LU, phospholipase A1) to catalyze the hydrolysis of soy phosphatidylcholine (PC). Immobilization of LU on Lewatit VP OC 1600 provided the highest fixation level (83.1 g/100 g) and greatest catalytic activity achieving 100 g/100 g l-α-GPC within 20 h and was therefore selected as the optimal system for biocatalysis. Immobilization of LU increased its positional specificity compared to free LU, as shown by a decrease in the production of the phosphocholine byproduct. Under the optimal conditions determined by response surface methodology, PC was completely hydrolyzed to l-α-GPC and required a simple purification via phase separation of the biphasic media to obtain a yield of ∼26.4 g l-α-GPC from 100 g PC, with a purity of 98.5 g/100 g. Our findings suggest a possibility of using the immobilized LU as a new biocatalyst for the l-α-GPC production.

Long-term Efficacy of S-1 Monotherapy or Capecitabine Plus Oxaliplatin as Adjuvant Chemotherapy for Patients with Stage II or III Gastric Cancer after Curative Gastrectomy: a Propensity Score-Matched Multicenter Cohort Study.

PURPOSE: To compare long-term disease-free survival (DFS) between patients receiving tegafur/gimeracil/oteracil (S-1) or capecitabine plus oxaliplatin (CAPOX) adjuvant chemotherapy (AC) for gastric cancer (GC). MATERIALS AND METHODS: This retrospective multicenter observational study enrolled 983 patients who underwent curative gastrectomy with consecutive AC with S-1 or CAPOX for stage II or III GC at 27 hospitals in Korea between February 2012 and December 2013. We conducted propensity score matching to reduce selection bias. Long-term oncologic outcomes, including DFS rate over 5 years (over-5yr DFS), were analyzed postoperatively. RESULTS: The median and longest follow-up period were 59.0 and 87.6 months, respectively. DFS rate did not differ between patients who received S-1 and CAPOX for pathologic stage II (P=0.677) and stage III (P=0.899) GC. Moreover, hazard ratio (HR) for recurrence did not differ significantly between S-1 and CAPOX (reference) in stage II (HR, 1.846; 95% confidence interval [CI], 0.693-4.919; P=0.220) and stage III (HR, 0.942; 95% CI, 0.664-1.337; P=0.738) GC. After adjustment for significance in multivariate analysis, pT (4 vs. 1) (HR, 11.667; 95% CI, 1.595-85.351; P=0.016), pN stage (0 vs. 3) (HR, 2.788; 95% CI, 1.502-5.174; P=0.001), and completion of planned chemotherapy (HR, 2.213; 95% CI, 1.618-3.028; P<0.001) were determined as independent prognostic factors for DFS. CONCLUSIONS: S-1 and CAPOX AC regimens did not show significant difference in over-5yr DFS after curative gastrectomy in patients with stage II or III GC. The pT, pN stage, and completion of planned chemotherapy were prognostic factors for GC recurrence.

Mulberry Fruit Extract Promotes Serum HDL-Cholesterol Levels and Suppresses Hepatic microRNA-33 Expression in Rats Fed High Cholesterol/Cholic Acid Diet.

Serum high-density lipoprotein cholesterol (HDL-C) levels and cholesterol excretion are closely associated with the risk of cardiovascular complications. The specific aim of the present study was to investigate the cholesterol lowering effect of mulberry fruit in rats fed a high cholesterol/cholic acid diet. Four-week supplementation with mulberry fruit extract significantly decreased serum and hepatic cholesterol (TC), serum low-density lipoprotein cholesterol (LDL-C), and fecal bile acid levels without changes in body weight and food intake (p < 0.05). Mulberry fruit extract significantly inhibited hepatic sterol-regulatory element binding protein (Srebp) 2 gene expression and upregulated hepatic mRNA levels of liver X receptor alpha (Lxr-α), ATP-binding cassette transporter 5 (Abcg5), and cholesterol 7 alpha-hydroxylase (Cyp7a1), which are involved in hepatic bile acid synthesis and cholesterol metabolism (p < 0.05). In addition, hepatic microRNA-33 expression was significantly inhibited by supplementation of mulberry fruit extract (p < 0.05). These results suggest the involvement of miR-33, its associated hepatic bile acid synthesis, HDL formation, and cholesterol metabolism in mulberry fruit-mediated beneficial effects on serum and hepatic lipid abnormalities.

Strong alkaline condition is preferable for producing 7,10-dihydroxy-8(E)-hexadecenoic acid from palmitoleic acid by Pseudomonas aeruginosa KNU-2B.

Microbial bioconversion of a given substrate is considered an efficient and eco-friendly tool for value-added industrial compound generation from natural products. Among natural products, unsaturated fatty acids have been used as substrates to produce various functional hydroxy fatty acids. In this study, we report the production of 7,10-dihydroxy-8(E)-hexadecenoic acid (DHD) from palmitoleic acid by a new strain, Pseudomonas aeruginosa KNU-2B. KNU-2B efficiently produced DHD from palmitoleic acid and required a strong alkaline condition for maximum DHD production. The maximum DHD amount produced under pH 10.0 and 48-h incubation at 27 °C and 150 rpm was 219.5 mg/100 mL culture. Other important nutritional factors were also investigated to obtain optimum DHD production.

Production of 7,10,12-trihydroxy-8(E)-octadecenoic acid from ricinoleic acid by Pseudomonas aeruginosa KNU-2B.

Microbial production of hydroxy fatty acids (HFAs) was widely studied because of important biological properties of HFAs. Among microorganisms producing HFAs, Pseudomonas aeruginosa PR3 was well known to produce various HFAs from different unsaturated fatty acids. Recently, a new variant species of P. aeruginosa PR3 was isolated and characterized, showing improved efficiency for producing 7,10-dihydroxy-8(E)-octadecenoic acid from oleic acid. In this study, we report the production of 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD) from ricinoleic acid by the newly isolated P. aeruginosa KNU-2B. TOD was efficiently produced from ricinoleic acid by KNU-2B with the maximum conversion yield of 56.7% under the optimum reaction conditions of pH 8.0 and 48-h incubation at 27 °C, 150 rpm. Under optimized reaction conditions, maximum TOD production reached 340.3 mg/100 mL of the culture. However, requirement of nutritional factors by KNU-2B for production of TOD were considerably different from those by PR3 strain.

Enzymatic preparation of food-grade l-α-glycerylphosphorylcholine from soy phosphatidylcholine or fractionated soy lecithin.

l-α-Glycerylphosphorylcholine (l-α-GPC) is a biosynthetic precursor for the neurotransmitter acetylcholine in humans, making it a useful as a cognitive enhancer for treating patients with stroke and dementia, including Alzheimer's disease. The aim of this study was to prepare l-α-GPC via Novozym 435 (an immobilized Candida antarctica lipase B)-catalyzed hydrolysis of soy phosphatidylcholine or a fractionated soy lecithin, from which triacylglycerols were completely removed, followed by food-grade solvent extraction of l-α-GPC from the reaction products. The reaction was performed in n-hexane-water biphasic media in a stirred-batch reactor. Phosphatidylcholine was completely hydrolyzed to l-α-GPC under optimal conditions: temperature, 55°C; water content, 100 wt% of the substrate weight; enzyme loading, 10 wt% of the substrate weight; and reaction time of 6 hr (for soy phosphatidylcholine) or 8 hr (for fractionated soy lecithin). Water-soluble fractions of the reaction products containing 98.6 area% l-α-GPC (from soy phosphatidylcholine) or 52.4 area% glycerophosphodiesters, including l-α-GPC (from fractionated soy lecithin), were obtained after phase separation of the media. The resulting products would be suitable for use as food-grade cognitive enhancers because of the use of enzymatic reaction and food-grade solvent extraction.