scholarly journals Formalin-casein enhances water absorbency of calcium alginate beads and activity of encapsulated Metarhizium brunneum and Saccharomyces cerevisiae

Author(s):  
Katharina M. Hermann ◽  
Alexander Grünberger ◽  
Anant V. Patel

AbstractThe control of root-feeding wireworms has become more challenging as synthetic soil insecticides have been progressively phased out due to environmental risk concerns. Innovative microbial control alternatives such as the so-called attract-and-kill strategy depend on the rapid and successful development of dried encapsulated microorganisms, which is initiated by rehydration. Casein is a functional additive that is already used in food or pharmaceutical industry due to its water binding capacity. Cross-linked forms such as formalin-casein (FC), exhibit altered network structures. To determine whether FC influences the rehydration of alginate beads in order to increase the efficacy of an attract-and-kill formulation for wireworm pest control, we incorporated either casein or FC in different alginate/starch formulations. We investigated the porous properties of alginate/starch beads and subsequently evaluated the activities of the encapsulated entomopathogenic fungus Metarhizium brunneum and the CO2 producing yeast Saccharomyces cerevisiae. Adding caseins altered the porous structure of beads. FC decreased the bead density from (1.0197 ± 0.0008) g/mL to (1.0144 ± 0.0008) g/mL and the pore diameter by 31%. In contrast to casein, FC enhanced the water absorbency of alginate/starch beads by 40%. Furthermore, incorporating FC quadrupled the spore density on beads containing M. brunneum and S. cerevisiae, and simultaneous venting increased the spore density even by a factor of 18. Moreover, FC increased the total CO2 produced by M. brunneum and S. cerevisiae by 29%. Thus, our findings suggest that rehydration is enhanced by larger capillaries, resulting in an increased water absorption capacity. Our data further suggest that gas exchange is improved by FC. Therefore, our results indicate that FC enhances the fungal activity of both fungi M. brunneum and S. cerevisiae, presumably leading to an enhanced attract-and-kill efficacy for pest control. Graphic abstract

1990 ◽  
Vol 55 (6) ◽  
pp. 1564-1566 ◽  
Author(s):  
DONNA M. CURRAN ◽  
BEVERLY J. TEPPER ◽  
THOMAS J. MONTVILLE

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 724
Author(s):  
Miguel L. Sousa-Dias ◽  
Vanessa Branco Paula ◽  
Luís G. Dias ◽  
Letícia M. Estevinho

This work studied the production of mead using second category honey and the immobilized cells of Saccharomyces cerevisiae in sodium alginate, with concentrations of 2% and 4%, and their reuse in five successive fermentations. The immobilized cells with 4% alginate beads were mechanically more stable and able to allow a greater number of reuses, making the process more economical. The fermentation’s consumption of sugars with free cells (control) and immobilized cells showed a similar profile, being completed close to 72 h, while the first use of immobilized cells finished at 96 h. The immobilized cells did not significantly influence some oenological parameters, such as the yield of the consumed sugars/ethanol, the alcohol content, the pH and the total acidity. There was a slight increase in the volatile acidity and a decrease in the production of SO2. The alginate concentrations did not significantly influence either the parameters used to monitor the fermentation process or the characteristics of the mead. Mead fermentations with immobilized cells showed the release of cells into the wort due to the disintegration of the beads, indicating that the matrix used for the yeast’s immobilization should be optimized, considering the mead production medium.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Dianbin Su ◽  
Xin-Di Zhu ◽  
Yong Wang ◽  
Dong Li ◽  
Li-Jun Wang

Abstract Citrus fiber dispersion with different concentrations (5–25 g/kg) was treated by high-pressure homogenization (90 and 160 MPa) for two cycles. The particle size distribution, hydration properties of powders, morphology and rheological measurements were carried out to study the microstructure and rheological properties changes by high-pressure homogenization (HPH). In conclusion, the HPH can reduce the particle size of fiber, improve the water holding capacity and water binding capacity. Furthermore, fiber shape can be modified from globular cluster to flake-like slices, and tiny pores can be formed on the surface of citrus fiber. The apparent viscosity, storage modulus and loss modulus were increased by HPH whereas the activation energy was reduced. The Hershcel–Bulkley model, Carreau model and Power Law mode were selected to evaluate the rheological properties.


2020 ◽  
Vol 20 (6) ◽  
Author(s):  
Robert W Behle

Abstract The walnut husk maggot, Rhagoletis sauvis (Loew) (Diptera: Tephritidae), causes damage to walnuts when maggots feed inside the husk. September applications of the entomopathogenic fungi Metarhizium brunneum F52 as microsclerotia laced granules to the soil in Illinois were evaluated for pest control based on adult emergence during the following summer. Over 3 yr in central Illinois, adult emergence began near 1 July, peaked before 23 July, and emergence extended as late as 23 August. One summer application of fungus (30 June) when pupae were present, did not reduce fly emergence. Of two September applications that targeted maggots as they move to the soil to pupate, one significantly reduced the number of flies emerging from treated plots when compared with untreated plots for one 7-d sample collected 29 July 2020. Emergence trap data show a defined peak adult emergence in July for central Illinois while September applications of granules containing Metarhizium brunneum (Petch) (Hypocreales: Clavicipitaceae) show shows potential to reduced subsequent fly emergence.


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 282
Author(s):  
Juan Fernández-Peláez ◽  
Priscila Guerra ◽  
Cristina Gallego ◽  
Manuel Gomez

One third of the food produced in the world is wasted. Bread is one of the most wasted foods both during the distribution process and in households. To use these breads, it is necessary to get to know the properties of the flours that can be obtained from them. The purpose of this work is to know how the type of bread and its zone (crumb or crust) influence the characteristics of the flours obtained from the wasted bread. For this, flours made from the crumbs and crusts of eight different breads have been analysed. Their hydration properties, cold and post-heating rheology and gelling properties as well as the colour of flours and gels have been studied. Bread flours present higher water-holding capacity (WHC) and water-binding capacity (WBC) values and higher elastic modulus (G’) and viscous modulus (G”) values, both in cold conditions and after heating, than wheat flours. However, they generate weaker gels. Crust flours, and the gels obtained from them, are darker than those from crumbs and their gels. In terms of hydration and rheology, pan and wholemeal bread flours are generally lower than other bread flours. These flours also generate softer gels, possibly caused by the dilution of starch with other components. It can be concluded that the properties shown by wasted bread flours allow them to be reintroduced in the food chain as an ingredient in different products.


Nutrients ◽  
2016 ◽  
Vol 8 (10) ◽  
pp. 615 ◽  
Author(s):  
Chengquan Tan ◽  
Hongkui Wei ◽  
Xichen Zhao ◽  
Chuanhui Xu ◽  
Yuanfei Zhou ◽  
...  

Author(s):  
Melanie Boucher ◽  
Cuilan Zhu ◽  
Sheena Holt ◽  
Lee-Anne Huber

The physiochemical properties and digestible, metabolizable, and predicted net energy contents in high-protein dried distillers’ grain (HiPro) were determined to assess the nutritive value for growing pigs. Twelve Yorkshire × Landrace barrows (initial body weight 25 ± 0.5 kg) were used in a partially replicated Latin square design over three periods (n = 7 or 8) and assigned to one of five experimental diets. In each period, pigs were adapted to diets for 7 d, followed by 5 d of total urine collection and fecal grab sampling. The experimental diets included a corn- and soybean-meal-based diet (CON) or diets containing dried distillers’ grains with solubles (DDGS) or HiPro to partially replace corn and soybean meal, without or with (i.e., DDGS+ and Hipro+) a multi-carbohydrase enzyme blend (0.05% inclusion). The HiPro ingredient contained half as much starch (2.6% vs. 5.2%; DM-basis), 20% more protein (32.5% vs. 27.1%), and had 14% greater water binding capacity versus DDGS. The digestible, metabolizable, and predicted net energy contents of the HiPro co-product were greater than DDGS for growing pigs (P < 0.05), but fibre-degrading enzymes were ineffective at improving energy values. The greater (available) energy and protein contents of HiPro make it a promising feed ingredient for inclusion in swine diets.


Author(s):  
Lynette Morgan

Abstract This chapter describes (i) major greenhouse pests (including insects, mites and nematodes) and pest control options focusing on integrated pest management (which involves the use of 'ofter' control options such as biological and microbial control combined with physical exclusion, pest trapping, resistant crops and other methods); (ii) selected diseases of hydroponic crops, including those caused by fungi, bacteria and viruses; and (iii) physiological disorders caused by non-living or non-infectious factors such as temperature, light, irrigation water quality and salinity, chemical injury (phytotoxicity), and cultural practices.


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