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In this work ultrasound-assisted solid-state enzymatic hydrolysis of rice bran to obtain fermentable sugars was investigated. For this purpose, process variables such as temperature, enzyme concentration and moisture content were evaluated during the enzymatic hydrolysis with and without ultrasound irradiation. The enzyme used is a blend of amylases derived from genetically modified strains of Trichoderma reesei. Kinetic of the enzymatic hydrolysis of rice bran at the constant-reaction rate period were measured. The best results for the ultrasound-assisted enzymatic hydrolysis was obtained using 3 wt% of enzyme, 60 oC and moisture content of 65 wt%, yielding 0.38 g sugar/g rice bran, whereas for the hydrolysis in the absence of ultrasound the highest yield was 0.20 g sugar/g rice bran using 3 wt% of enzyme, 60 oC and moisture content of 50 wt%. The use of ultrasound-assisted enzymatic hydrolysis of rice bran was intensified, obtaining around 74% more fermentable sugar than in the absence, showing that the use of ultrasound is a promising technology to be used in enzymatic reaction as an alternative of process intensification. En este trabajo se investigó la hidrólisis enzimática de salvado de arroz por ultrasonido para obtener glucosa. Se evaluaron variables del proceso tales como la temperatura, la concentración de enzima y la humedad para la hidrólisis enzimática con y sin la aplicación de la irradiación ultrasónica. La enzima utilizada fue una mezcla de amilasa de Trichoderma reesei. Se evaluó la cinética de la hidrólisis enzimática de salvado de arroz en el período constante de la velocidad de reacción. Los mejores resultados para la hidrólisis enzimática con la aplicación de ultrasonidos fueran utilizando 3% de enzima, 60 ° C y 65% de humedad, el rendimiento obtenido fue 0,38 g de azúcar / g de salvado de arroz, mientras que el más alto rendimiento de la hidrólisis en ausencia de ultrasonido fue 0,20 g de azúcar / g de salvado de arroz utilizando 3% de enzima, 60 ° C y 50% de humedad. El uso de ultrasonido mejora la hidrólisis enzimática permitiendo obtener 74% más azúcares fermentables que en la ausencia de ultrasonidos, lo que demuestra que el uso de ultrasonido es una promisora tecnología que se puede utilizar en las reacciones enzimáticas y como una alternativa de intensificación de procesos.

In this work ultrasound-assisted solid-state enzymatic hydrolysis of rice bran to obtain fermentable sugars was investigated. For this purpose, process variables such as temperature, enzyme concentration and moisture content were evaluated during the enzymatic hydrolysis with and without ultrasound irradiation. The enzyme used is a blend of amylases derived from genetically modified strains of Trichoderma reesei. Kinetic of the enzymatic hydrolysis of rice bran at the constant-reaction rate period were measured. The best results for the ultrasound-assisted enzymatic hydrolysis was obtained using 3 wt % of enzyme, 60 ºC and moisture content of 65 wt %, yielding 0.38 g sugar/g rice bran, whereas for the hydrolysis in the absence of ultrasound the highest yield was 0.20 g sugar/g rice bran using 3 wt % of enzyme, 60 ºC and moisture content of 50 wt % . The use of ultrasound-assisted enzymatic hydrolysis of rice bran was intensified, obtaining around 74 % more fermentable sugar than in the absence, showing that the use of ultrasound is a promising technology to be used in enzymatic reaction as an alternative of process intensification. En este trabajo se investigó la hidrólisis enzimática de salvado de arroz por ultrasonido para obtener glucosa. Se evaluaron variables del proceso tales como la temperatura, la concentración de enzima y la humedad para la hidrólisis enzimática con y sin la aplicación de la irradiación ultrasónica. La enzima utilizada fue una mezcla de amilasa de Trichoderma reesei. Se evaluó la cinética de la hidrólisis enzimática de salvado de arroz en el período constante de la velocidad de reacción. Los mejores resultados para la hidrólisis enzimática con la aplicación de ultrasonidos fueran utilizando 3% de enzima, 60 ° C y 65% de humedad, el rendimiento obtenido fue 0,38 g de azúcar / g de salvado de arroz, mientras que el más alto rendimiento de la hidrólisis en ausencia de ultrasonido fue 0,20 g de azúcar / g de salvado de arroz utilizando 3 % de enzima, 60 ° C y 50 % de humedad. El uso de ultrasonido mejora la hidrólisis enzimática permitiendo obtener 74 % más azúcares fermentables que en la ausencia de ultrasonidos, lo que demuestra que el uso de ultrasonido es una promisora tecnología que se puede utilizar en las reacciones enzimáticas y como una alternativa de intensificación de procesos.

The 19th International Electronic Conference on Synthetic Organic Chemistry session Bioorganic, Medicinal and Natural Products Chemistry In the category of microorganism, fungi are considered as the special class of microbes responsible for opportunistic pathogenic infections in humans species. Due to the side effects of commercially available antifungal drugs and the emergence of new drug resistant fungal species in the past few years has forced the researchers to search for novel and efficient antifungal drug molecules. The 1,3,4-oxadiazoles scaffold is associated with diverse biological activities. The multipurpose use of the Mannich bases in pharmaceutical chemistry provoked us to prepare a new series of 1,3,4-oxadiazole Mannich bases derivatives, as antifungal agents. Herein we report Molecular sieves and Ultrasound assisted synthesis of novel series of Mannich bases of the 5-substituted 1,3,4-oxadiazole-2-thiones by amino methylation with paraformaldehyde and substituted primary / secondary amines and their evaluation for antifungal activity .The structures of the newly synthesized compounds were determined by IR, NMR and Mass spectral study. The synthesized compounds exhibited interesting moderate to excellent antifungal activity against Candida albicans (NCIM 3557),Candida albicans(NCIM3471), Candida glabrata(NCIM3237), Cryptococcus neoformans (NCIM 3542),Cryptococcus neoformans(NCIM 3378),Aspergillus fumigates(NCIM 902), Aspergillus niger( NCIM 628) using Flucanazole as a standard reference drug. The synthesised compounds 6d, 6f ,6g, 6h and 6j exhibited promising antifungal activity as fungi static agents

© 2015 Elsevier Ltd. Herein, we developed a novel integrated device to perform phase separation based on ultrasound-assisted, salt-induced, liquid-liquid microextraction for determination of five fluoroquinones in meats by HPLC analysis. The novel integrated device consisted of three simple HDPE (high density polyethylene) parts that were used to separate the solvent from the aqueous solution prior to retrieving the extractant. The extraction parameters were optimized using the response surface method based on central composite design: 589μL of acetone solvent, pH2.1, 4.1min extraction time and 3.5g of Na2SO4. The limits of detection were 0.056-0.64μgkg-1 and recoveries were 87.2-110.6% for the five fluoroquinones in muscle tissue from fish, chicken, pork and beef. This method is easily constructed from inexpensive materials, extraction efficiency is high, and the approach is compatible with HPLC analysis. Thus, it has excellent prospects for sample pre-treatment and analysis of fluoroquinones in meat samples.

Background Extraction prior to component analysis is the primary step in the recovery and isolation of bioactive phytochemicals from plant materials. Methods Response surface methodology was applied to optimize ultrasound-assisted extraction conditions followed by ultra high performance liquid chromatography (UHPLC) to achieve high catechin, myricetin, and quercetin contents, and high antioxidant and anticancer activities in the curry leaf extracts. The antioxidant and anticancer activities of the leaf extracts were determined by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, respectively. The central composite experimental design (3-level, 3-factorial) was employed to consider the effects of ultrasonic power (80–150 W), temperature (40–80°C), and methanol dilution (40–80%) on the properties of the curry leaf extracts. Results It was found that ultrasonic power of 145.49 W at 55.9°C with 80% methanol was the most appropriate set of conditions for the extraction of catechin, myricetin, and quercetin from curry leaves with the consequent high antioxidant activity. Using the optimum extraction conditions, the extraction yields of catechin, myricetin, and quercetin were 0.482, 0.517, and 0.394 mg/g DW, respectively, and the antioxidant activity was enhanced to 83%. The optimized extract showed more distinct anticancer activity against HeLa cancer cells in a concentration of 67.2 μg/mL (P

In this study, the bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracted by two extraction methods (solvent and ultrasound‐assisted) with three solvents (ethanol, water and ethanol–water) were compared to supercritical fluid extraction. The antioxidant activities of skin and pulp extracts were evaluated and compared to tertiary butylhydroquinone (TBHQ) using 2, 2‐diphenyl‐1‐picrylhydrazyl (DPPH˙) radical scavenging, β‐carotene bleaching, and the Rancimat assays. In DPPH assay solvent extracts of skin by ethanol (SSE) and ethanol–water (SSEW) showed strong inhibitory activity. The SSEW also showed the highest inhibition percentage of 85.58% by the β‐carotene bleaching assay and longest induction time of 4.78 h by the Rancimat method. The large amount of tocopherols and phenolics contained in the skin extract may cause its strong antioxidant ability. The results indicated that the solvent extraction with ethanol–water produced the maximum extraction yield of phenolic and tocopherol compounds from loquat fruit skin and pulp. Furthermore, solvent extraction was the most effective in antioxidant activity of the extracts compared to other extraction techniques.