Diversity in secondary metabolites including mycotoxins from strains of aspergillus section nigri isolated from raw cashew nuts from Benin, West Africa

Open access JournalIn a previous study, raw cashew kernels were assayed for the fungal contamination focusing on strains belonging to the genus Aspergillus and on aflatoxins producers. These samples showed high contamination with Aspergillus section Nigri species and absence of aflatoxins. To investigate the diversity of secondary metabolites, including mycotoxins, the species of A. section Nigri may produce and thus threaten to contaminate the raw cashew kernels, 150 strains were isolated from cashew samples and assayed for their production of secondary metabolites using liquid chromatography high resolution mass spectrometry (LC-HRMS). Seven species of black Aspergilli were isolated based on morphological and chemical identification: A. tubingensis (44%), A. niger (32%), A. brasiliensis (10%), A. carbonarius (8.7%), A. luchuensis (2.7%), A. aculeatus (2%) and A. aculeatinus (0.7%). From these, 45 metabolites and their isomers were identified. Aurasperone and pyranonigrin A, produced by all species excluding A. aculeatus and A. aculeatinus, were most prevalent and were encountered in 146 (97.3%) and 145 (95.7%) isolates, respectively. Three mycotoxins groups were detected: fumonisins (B2 and B4) (2.7%) ochratoxin A (13.3%), and secalonic acids (2%), indicating that these mycotoxins could occur in raw cashew nuts. Thirty strains of black Aspergilli were randomly sampled for verification of species identity based on sequences of β-tubulin and calmodulin genes. Among them, 27 isolates were positive to the primers used and 11 were identified as A. niger, 7 as A. tubingensis, 6 as A. carbonarius, 2 as A. luchuensis and 1 as A. welwitschiae confirming the species names as based on morphology and chemical features. These strains clustered in 5 clades in A. section Nigri. Chemical profile clustering also showed also 5 groups confirming the species specific metabolites production

Towards a novel framework of barriers and drivers for digital transformation in industrial supply chains

© 2019 PICMET. Businesses across all sectors are facing the complexity of an increasingly digital economy. Digital transformation offers vast opportunities to businesses and entire supply chains. While many investments are targeted at the organization level, the supply chain perspective can lead to even greater impacts on business performance. However, as supply chains involve interconnections between multiple actors, comprehensive digitalization initiatives at this level are very complex. Several strategic factors affect decision-making around digital investments. For this reason, a framework that categorizes all these factors is needed in order to help managers build digitalization strategies for their supply chains. In this paper, based on a review of existing literature, we give indications for a framework encompassing barriers to and drivers for digital transformation in the context of industrial supply chains. Our framework preliminarily allocates these factors by using two dimensions. The first one classifies them using several categories: financial, knowledge and skills, regulatory, technological, market, organizational, and cultural. The second dimension classifies determinants at the level on which actions can be made, i.e. market, supply chain, or organization. The framework can support organizations to exploit the opportunities provided by digitalization of supply chains and will help managers understand the complexity involved

Antitumor activity of urease-free L-asparaginase with low glutaminase coactivity produced by marine-derived Aspergillus flavus

L-asparaginase, which has a high therapeutic effect in various cancer diseases, hydrolyzes L-asparagine to aspartate and ammonia and is mainly used in treating Acute Lymphoblastic Leukaemia. This study aims to investigate the L-asparaginase production potential of marine filamentous fungi and the partial purification and characterization of the L-asparaginase. The rapid plate screening method was used to measure the L-asparaginase activity of 94 marine fungi. L-asparaginase producers were then screened for glutaminase and urease activity. The selected extracellular L-asparaginase producer, Aspergillus flavus MF10, showed 2.82 U/mL L-asparaginase activity in small-scale fermentation. L-asparaginase was concentrated by ultrafiltration followed by acetone precipitation. The specific activity of the enzyme, purified 4,8 fold by partial purification, was determined as 259 U/mg. There were no urease and glutaminase activities in the fermentation broth, but low glutaminase activity (1.27 U/mL) was detected in the concentrated fermentation broth. The optimum pH and temperature of the L-asparaginase were 8.0 and 40 °C, respectively. L-asparaginase was stable at pH 7.0–8.0 and can maintain its activity at 70% at 40 °C after 1 h. While the enzyme decreased the viability of SH-SY5Y (neuroblastoma) to 43% and LNCap (prostate cancer) to 61%, it did not show cytotoxic effects in healthy cell line L929 (fibroblast). It was also determined that L-asparaginase showed low cytotoxicity in HaCaT (keratinocyte) cells. In conclusion, it was shown that urease-free L-asparaginase with low glutaminase coactivity, produced from marine-derived A. flavus MF10, has the potential for medical use. © 2023 Elsevier LtdFYL-2020-2226

Some characteristics and isolation of novel thermostable ß-galactosidase from Thermus oshimai DSM 12092

The ß-galactosidases belong to the class of hydrolytic enzymes and have been used as lactose hyrolysis. The enzyme is used in reducing lactose milk production, an outstanding industrial product used by a large lactoseintolerant population. This is the first detailed report of some characteristics of ß-galactosidase and the gene encoding ß-galactosidase in Thermus oshimai DSM 12092. The growth rate (µ, 1/h), and the doubling time (tD, h) for T. oshimai grown both in shaking flasks and in a bioreactor were determined. The optimal temperature and pH for ß-galactosidase were determined as 75°C and 7. 4, respectively. This enzyme was thermostable and was retained by more than 70% at 90°C for 3 h. The ß-galactosidase from T. oshimai DSM 12092 was more stable in basic pH and Zn2+ was the most effective divalent cation. Also, 2 steps of purification consisting of ammonium sulfate precipitation and gel filtration were employed and purified 32-fold. © 2013 The Korean Society of Food Science and Technology and Springer Science+Business Media Dordrecht

Phosphate uptake performance of bacteria isolated from a full-scale Izmir municipal wastewater treatment plant

WOS: 000290406200008PubMed ID: 21877535This study investigated the phosphate uptake capacities of bacteria isolated from aerobic and anaerobic phosphate removal tanks at a municipal wastewater treatment plant in Izmir, Turkey, removing chemical oxygen demand to nitrogen (COD-N) and phosphorus (P) on a full-scale basis. Conventional plating techniques and an enrichment culture method were used to isolate the colonies, with a total of 91 monoculture isolates from the sludge samples being subjected to phosphate uptake studies. A total of 64 of these isolates had high phosphate uptake capacities ranging from 3.7 x 10-10 to 1.0 x 10-12 mg PO43- cell-1, and only 11 of the strains with high phosphate uptake were Gram-negative. The highest phosphorus uptake value was 3.7 x 10-10 mg PO4-3 cell-1, which was achieved by Gram-positive bacteria. Gram-negative strains were identified as Acinetobacter baumannii with a 99% probability and as Pseudomonas aeruginosa with a 96-98% probability (API 20 NE)

The development of the online player type scale: Construct validity and reliability testing

The present study outlines the development of the Online Player Type Scale (OPTS) utilizing a motivational taxonomy developed. This taxonomy was comprehensively reviewed to create scale items, and the conceptual framework of the scale was defined. The study group was comprised of 1,479 students attending grades 5 to 8 of a private school. A purposive sampling method was used to recruit the study group, and playing any videogame frequently was the criterion to be included in the sample. The construct validity and reliability testing showed the OPTS comprised four factors: achievement-oriented (ACH), socialization-oriented (SOC), exploration-oriented (EXP), and competition-oriented (COMP). The Cronbach alpha internal consistency coefficients and composite reliability coefficients were 0.89 and 0.99 for KIL, 0.83 and 0.98 for EXP, 0.83 and 0.98 for SOC, and 0.94 and 0.99 for ACH. It is concluded that the Online Player Type Scale is a valid and reliable instrument for assessing gaming motivation. Copyright © 2020, IGI Global

The development of the online player type scale: Construct validity and reliability testing [Book Chapter

The present study outlines the development of the Online Player Type Scale (OPTS) utilizing a motivational taxonomy developed. This taxonomy was comprehensively reviewed to create scale items, and the conceptual framework of the scale was defined. The study group was comprised of 1,479 students attending grades 5 to 8 of a private school. A purposive sampling method was used to recruit the study group, and playing any videogame frequently was the criterion to be included in the sample. The construct validity and reliability testing showed the OPTS comprised four factors: achievement-oriented (ACH), socialization-oriented (SOC), exploration-oriented (EXP), and competition-oriented (COMP). The Cronbach alpha internal consistency coefficients and composite reliability coefficients were 0.89 and 0.99 for KIL, 0.83 and 0.98 for EXP, 0.83 and 0.98 for SOC, and 0.94 and 0.99 for ACH. It is concluded that the Online Player Type Scale is a valid and reliable instrument for assessing gaming motivation. © 2023, IGI Global. All rights reserved