Enrichment of Polyunsaturated fatty acids from catfish oil with immobilized Rhizopus oryzea lipase

Nowadays, Pangasius hypophthalmus fillet is one of the main marine products in Vietnamese Mekong River Delta with over three hundred thousand tons per year. One of the byproducts of this industry is fat, about one hundred thousand tons per year. That byproduct has been only used in animal foodstuff industry after oil extracting or it becomes waste. In order to increase the quality of Pangasius hypophthalmus oil, we have enriched PUFA in the oil by hydrolysis with immobilized Rhizopus oryzea lipase. Lipase has been immobilized on celite by absorption method. Immobilization experiments have been designed in a two-level full factorial model with three factors. The fish oil has been hydrolyzed with immobilized lipase to enrich PUFA with optimized parameters found out: the ratio of enzyme to support of 1:10 g/g, the ratio of phosphate buffer volume to support weight of 30.55 ml/g, incubation time of 5.15 hours. The result has showed that 60-minute hydrolysis is the most appropriate. Additionally, the oil iodine value has increased from 71.4 to 97.4, and DHA concentration has risen from 1156mg/kg to 1916mg/kg

Effects of some factors on carotenoid biosynthesis by Rhodotorula Muclaginosa

Carotenoid compounds are the popular natural antioxidants which are often isolated from plants. There have been more and more researches on carotenoid biosynthesis towards lowering product prices. In this study, in order to produce carotenoid, Rhodotorula mucilaginosa was grown on aqueous media composed of carbon source (glucose, glycerol), nitrogen source (yeast extract, (NH4)2SO4). The optimum nutrient concentration was 10g/L glucose, 10g/L glycerol, the ratio of yeast extract and (NH4)2SO4 (3:7). The fermentation time for obtaining the highest carotenoid yield was 10 days in our research condition. Additionally, some oxidative stress environment for Rhodotorula mucilaginosa was be studied. The result has shown that the low level of Cu2+ (4.5mM) or 1% H2O2 solution (% v/v) in the fermentation media could increase the carotenoid biosynthesis

Effects of nutriental and environmental conditions on carotenoid biosynthesis by Rhodotorula sp.

Carotenoid compounds are popular natural antioxidants which are commonly isolated from the plants. Recently, there have been many researches on carotenoid biosynthesis towards low cost products. In this study, Rhodotorula sp. was grown on an agricultural byproduct (corncobs) as a matrix in solid-state fermentation. Essential nutrients were added with different concentrations to optimize condition for the carotenoid biosynthesis. Effects of other environmental factors such as moisture content and fermentation time on the yield were also characterized. The optimal nutrient composition for the yeast’s growth and carotenoid biosynthesis is a compound of 500μg nitrogen and 16mg carbon in 100g matrix. Additionally, the moisture content of 80% is the best for producing carotenoid by this yeast strain. The fermentation time for the highest carotenoid yield is observed after 8 days

Bioefficacy of leaf extracts from Pouzolzia zeylanica (L.) Benn against diamondback moth plutella xylostella in Viet Nam

In Viet Nam, Pouzolzia zeylanica (L.) Benn is a native plant and has been demonstrated its applicability as a medical plant. Additionally, Pouzolzia zeylanica was used to control fly larvae during food processing due to insecticidal activity. We optimized the extraction of Pouzolzia zeylanica by ethanol at different conditions: concentration, the ratio of solid (material) - liquid (ethanol volume) (mg/ml) and the extraction time (hour). Results indicated that extraction yield was effected by all of the factors. The optimized extraction yield was 6.85% (Y) with ethanol concentration at 96 percent ethanol (Z1), the ratio solid to liquid is 1: 25 (mg/ml) (Z2) and extraction time is 4 days (Z3). We tested the efficiency of leaf extracts from Pouzolzia zeylanica and antifeedant activity against diamondback moth Plutella xylostella at different leaf extract concentrations. Results indicated that 80% mortality induced by those compounds was recorded on Plutella xylostella second instars at 30% leaf extract concentration and had significant difference compared to the control (P=0.0000); the leaf extract affected the ratio of pupation, adult emergence and antifeedant activity of P. xylostella (P=0.0000). The obtained results promise a potential of using Pouzolzia zeylanica as biopesticide in Viet Nam

Chemical composition and cytotoxic activity of the essential oils of Cymbopogon citratus L. Grown in phu tho province

Culms and leaves of Cymbopogon citratus L. were collected from two regions of Phu Tho province (Thanh Son and Phu Ninh) and used as materials for essential oil extraction. Oils obtained were steam-distilled, analyzed for chemical composition and evaluated for cytotoxic activity against three different cancer cell lines. The GC/MS analysis showed that citral is the major content of the steam-distilled essential oils which was found in the range of 64.15-76.22%. Camphene was found only in culm oils of both regions but it was not detected in the leaf oils. Interestingly, the isomer forms of ocimene present at higher content in the culm oils than in the leaf oils whereas myrcene content in the leaf oils is higher than that in the culm oils. In a cytotoxicity test, four essential oils of culms and leaves of C. citratus from Thanh Son and Phu Ninh showed potent activity against A549 (human lung carcinoma) cell line with the IC50 values ranging from 4.01±0.39 to 6.3±0.54 µg/ml. The essential oils (culms and leaves) from Phu Ninh exhibited moderate effects on the Hela (human cervical adenocarcinoma) cells with the IC50 values of 19.43±1.16 and 42±2.41 µg/ml, respectively. However, they were inactive against the human hepatocellular carcinoma Hep3B cell line. The essential oils from Thanh Son exhibited potent cytotoxic activity against Hela and Hep3B cell lines with the IC50 values ranging from 1.18±0.26 to 8.91±0.32 µg/ml. The results indicated that the essential oils of C. citratus from Thanh Son, Phu Tho could be considered as a promising candidate for the natural sources of anticancer agents

An Outbreak of Severe Infections with Community-Acquired MRSA Carrying the Panton-Valentine Leukocidin Following Vaccination

Background: Infections with community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging worldwide. We investigated an outbreak of severe CA-MRSA infections in children following out-patient vaccination. Methods and Findings: We carried out a field investigation after adverse events following immunization (AEFI) were reported. We reviewed the clinical data from all cases. S. aureus recovered from skin infections and from nasal and throat swabs were analyzed by pulse-field gel electrophoresis, multi locus sequence typing, PCR and microarray. In May 2006, nine children presented with AEFI, ranging from fatal toxic shock syndrome, necrotizing soft tissue infection, purulent abscesses, to fever with rash. All had received a vaccination injection in different health centres in one District of Ho Chi Minh City. Eight children had been vaccinated by the same health care worker (HCW). Deficiencies in vaccine quality, storage practices, or preparation and delivery were not found. Infection control practices were insufficient. CA-MRSA was cultured in four children and from nasal and throat swabs from the HCW. Strains from children and HCW were indistinguishable. All carried the Panton-Valentine leukocidine (PVL), the staphylococcal enterotoxin B gene, the gene complex for staphylococcal-cassette-chromosome mec type V, and were sequence type 59. Strain HCM3A is epidemiologically unrelated to a strain of ST59 prevalent in the USA, althoughthey belong to the same lineage. Conclusions. We describe an outbreak of infections with CA-MRSA in children, transmitted by an asymptomatic colonized HCW during immunization injection. Consistent adherence to injection practice guidelines is needed to prevent CA-MRSA transmission in both in- and outpatient settings

Safety and efficacy of fluoxetine on functional outcome after acute stroke (AFFINITY): a randomised, double-blind, placebo-controlled trial

Background Trials of fluoxetine for recovery after stroke report conflicting results. The Assessment oF FluoxetINe In sTroke recoverY (AFFINITY) trial aimed to show if daily oral fluoxetine for 6 months after stroke improves functional outcome in an ethnically diverse population. Methods AFFINITY was a randomised, parallel-group, double-blind, placebo-controlled trial done in 43 hospital stroke units in Australia (n=29), New Zealand (four), and Vietnam (ten). Eligible patients were adults (aged ≥18 years) with a clinical diagnosis of acute stroke in the previous 2–15 days, brain imaging consistent with ischaemic or haemorrhagic stroke, and a persisting neurological deficit that produced a modified Rankin Scale (mRS) score of 1 or more. Patients were randomly assigned 1:1 via a web-based system using a minimisation algorithm to once daily, oral fluoxetine 20 mg capsules or matching placebo for 6 months. Patients, carers, investigators, and outcome assessors were masked to the treatment allocation. The primary outcome was functional status, measured by the mRS, at 6 months. The primary analysis was an ordinal logistic regression of the mRS at 6 months, adjusted for minimisation variables. Primary and safety analyses were done according to the patient's treatment allocation. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611000774921. Findings Between Jan 11, 2013, and June 30, 2019, 1280 patients were recruited in Australia (n=532), New Zealand (n=42), and Vietnam (n=706), of whom 642 were randomly assigned to fluoxetine and 638 were randomly assigned to placebo. Mean duration of trial treatment was 167 days (SD 48·1). At 6 months, mRS data were available in 624 (97%) patients in the fluoxetine group and 632 (99%) in the placebo group. The distribution of mRS categories was similar in the fluoxetine and placebo groups (adjusted common odds ratio 0·94, 95% CI 0·76–1·15; p=0·53). Compared with patients in the placebo group, patients in the fluoxetine group had more falls (20 [3%] vs seven [1%]; p=0·018), bone fractures (19 [3%] vs six [1%]; p=0·014), and epileptic seizures (ten [2%] vs two [<1%]; p=0·038) at 6 months. Interpretation Oral fluoxetine 20 mg daily for 6 months after acute stroke did not improve functional outcome and increased the risk of falls, bone fractures, and epileptic seizures. These results do not support the use of fluoxetine to improve functional outcome after stroke

Formulation of black pepper (Piper nigrum L.) essential oil nano-emulsion via phase inversion temperature method

Recent trends in preservation of processed foods involve the use of natural compounds, rather than chemically synthesized additives, to simultaneously confer antimicrobial properties and prevent fat oxidation. In this regard, black pepper essential oils, due to its diversity in biological activities, have been increasingly popular. The compounds are often used in relatively low amounts and in the form of nanoparticles to permit well blending into foods or uniform dispersion on the surface of fresh meat. The purpose of this study is to determine experimental parameters of a nano-emulsion formation process from black pepper essential oil via the phase inversion temperature (PIT) technique. The study results showed that the system achieved the optimal nano-emulsion under following condition: the ratio by weight of water: Tween-80: oil = 86:9.7:4.3, the stirring speed of nano-emulsions at 500 rpm for 45 min (heating at 75°C for 30 min and then rapidly cooling at 5°C for 15 min)

Modeling the extraction process of pomelo (citrus maxima (burm.) Merr.) Peel essential oil by steam distillation on a production scale (500kg/batch)

The development of larger-scale extraction processes depends on process kinetics. A production scale of around 500 kg/batch was used in this study to experimentally extract pomelo essential oil by steam distillation. In this study, three models including Model of simultaneous washing and diffusion, Model of instantaneous washing followed by diffusion, and Model of diffusion without washing are considered for evaluation. The most appropriate kinetic model kinetics were chosen using the coefficient of determination (R2) and percentage of variance (%q). The findings demonstrate that the analyzed model of concurrent washing and diffusion suited the experimental data. The results show that in this model, the value of R2 = 0.99795 and q = 0.89285 ± 0.0061, which has the highest value of the three models. The extraction process through this production system was successfully described using a kinetic model, which gave information on the extraction process

Application of pomelo essential oil (

In order to minimize the toxic effects of scent compounds from chemicals to the environment and humans. Besides, the increasing demand of consumers for natural compounds, so the research team has conducted a search for compounds with good odor-producing ability and high activity extracted from the species plants in nature. The study was carried out based on the investigation of influencing parameters in product formulations such as carrier, essential oil, emulsifier, solvent. Research results are based on the evaluation of the product's volatility and appearance. At the same time, it is also shown that pomelo essential oil has the ability to combine with many other ingredients in the product without being denatured, with the content of 4% pomelo essential oil is diffused with a pleasant scent that is not pungent and can High deodorizing capacity in the air. The obtained research results have opened new perspectives on the applicability and potential of essential oils in the aromatherapy industry or cosmetic field, used as an alternative to artificial fragrances with properties of environmental friendliness