In Vitro and In Vivo Feedstuff Digestibility for Snook,Centropomus undecimalis,Juveniles

The degree of hydrolysis (DH) of the ingredients was evaluated for Centropomus undecimalis juveniles. The in vitro experiment included wheat gluten (WG), corn gluten (CG), soybean meal (SBM) and pretreated phytase (SBM + phytase), soy protein concentrate (SPC), canola meal (CAN) and pretreated phytase (CAN + phytase), poultry byproduct meal (PBPM), chicken meal (CHKM), dried whey (DW), Pota meal (PM: mix of giant squid, fish soluble protein concentrate, crustacean meal, and fish oil), and Protiblend (PTB: aquatic and render mix). The highest acidic DH occurred with PTB (0.38 ± 0.06), CHKM (0.33 ± 0.3), and PBPM (0.25 ± 0.03). In the alkaline condition, PTB (1.6 ± 0.17 and 0.98 ± 0.05 for pyloric caeca and intestine, respectively) and CG (1.04 ± 0.4 and 0.75 ± 0.2 for caeca and intestine, respectively) provided the highest DH values. In vitro digestibility demonstrated that PTB was the highest (85.3%) followed by PBPM (51.4%), CAN + phytase (47.6%), CG (45.1%), and CHKM (46.5%). The in vivo experiment concerned the WG, CHKM, PBPM, PM, and PTB diets plus a reference diet with fishmeal (Ref diet). The total %DH was different (P < 0.05) with the lowest values for the WG diet (0.34 ± 0.09%) and Ref diet (0.34 ± 0.15). Free amino acid released during digestion was displayed for these diets and a bifactorial analysis produced no difference (P > 0.05). The apparent digestive coefficients ranged from 89.8 to 92.9% for protein and from 68 to 71.4% for energy.     

Understanding physical clogging in drip irrigation: in situ,in-lab and numerical approaches

Dripper clogging is a major drawback of microirrigation systems that must be addressed to improve their efficiency and durability. Particle-induced clogging is first studied in situ. The experiments consist in observing in real conditions the behavior of a series of drippers fitted on an agricultural plot in the south of France. The plot is supplied from a canal with Durance River water. The latter is loaded with sediments that gradually clog drippers and filters. Water analysis reveal that physicochemical clogging prevails over biological clogging. This characterization helps in setting in-lab experiment protocol. Indeed, besides field observation of clogging, laboratory analyses of both the irrigation water and the clogging material are performed with reactive and inert clay: smectite and an illite–calcite mix. A surprising tendency is observed: Salt concentration in smectite seeded water decreases the clogging, whereas it increases agglomerate size. Computational fluid dynamic simulations are carried out to investigate the impact of particles on flow behavior. Results demonstrate that clay particles interacting with the flow govern the complex structure of the fluid velocity fields inside the dripper labyrinth channel.     

Induction of resistance to Sclerotium rolfsii in different varieties of onion by inoculation with Trichoderma asperellum

We evaluated the ability of Trichoderma asperellum Samuels, Lieckfeldt & Nirenberg to induce resistance to the fungal plant pathogen, Sclerotium rolfsii Saccardo, in three onion (Allium cepa L.) varieties. Both the severity of disease and the activities of glucanase, chitinase and peroxidase (enzymes involved in plant resistance) were evaluated in onions inoculated with T. asperellum alone, S. rolfsii alone, or both T. asperellum and S. rolfsii (dual-inoculation) and compared to uninoculated (control) plants. In dual inoculations, the presence of T. asperellum reduced the severity of disease symptoms caused by S. rolfsii. Inoculation with T. asperellum alone increased glucanase, chitinase and peroxidase activity in bulbs, roots and leaves of all three onion varieties compared to uninoculated controls; bulbs of the variety Red Satan (RS) had the highest enzyme activity. In plants inoculated with S. rolfsii alone, enzyme activity was only increased in bulbs and roots compared to uninoculated controls. The highest levels of enzyme activity also occurred only in bulbs and roots of plants that had been dual-inoculated with T. asperellum and S. rolfsii. Plants of the RS variety showed the highest enzyme activities (both constitutive and induced) and showed the lowest severity of disease. Therefore, application of T. asperellum has potential as a biological control alternative to synthetic fungicides for protection of onion crops against infection by S. rolfsii. This protection depends on both constitutive and induced defence responses and varies amongst onion varieties.     

Amorphous Aluminum Hydroxide Control on Sulfate and Phosphate in Sediment-Solution Systems

We experimentally determined the adsorption characteristics of natural, freshly precipitated Al(OH)₃ for SO₄ and PO₄. The fresh Al precipitate occurred in stream sediment of Jachymov Stream (Czech Republic). The Al-rich sediment strongly adsorbed added PO₄ prior to acidification experiment; this sorbed PO₄ was released only after substantial dissolution of the sediment, at pH?<?3.67. Sorption of P by Al(OH)₃ appears to be an important control on dissolved PO₄ concentration in surface waters, unless there is a large excess of PO₄. Acidification of the sediment-solution system caused protonation of the sediment surface, thereby increasing the adsorption capacity for SO₄. Maximum SO₄ adsorption occurred at pH 4.2, below which dissolution of the sediment offset the increasing anion adsorption capacity, and formation of AISO₄ ⁺ inhibited the increasing SO₄ adsorption capacity. This research demonstrates that there are important pH thresholds for anion adsorption in freshwaters below which dissolution of the Al(OH)₃ substrate reduces total capacity for anion adsorption. In freshwaters, with sufficient concentrations of suspended Al(OH)₃, or in Al(OH)₃-rich sediment, PO₄ mobility will be severely restricted. Suspended Al(OH)₃ in acidified surface waters cannot strongly influence SO₄ concentrations because of the considerably higher total SO₄ concentrations compared to the available surface area.     

Relationship Between Soft Wheat Flour Physicochemical Composition and Cookie‐Making Performance

Nowadays in Argentina, cookies, crackers, and cakes are made of flour obtained from bread wheat with additives or enzymes that decrease the gluten strength but increase production costs. The present research work aims to study the relationship between flour physicochemical composition (particle size average [PSA], protein, damaged starch [DS], water soluble pentosans [WSP], total pentosans [TP], and gluten), alkaline water retention capacities behavior, solvent retention capacities profile (SRC) and cookie‐making performance in a set of 51 adapted soft wheat lines with diverse origin to identify better flour parameters for predicting cookie quality. Cookie factor (CF) values were 5.06–7.56. High and significant negative correlations between sucrose SRC (–0.68), water SRC (–0.65), carbonate SRC (–0.59), and CF were found, followed by lactic SRC that presented a low negative but significant correlation (r = –0.35). The flour components DS (r = –0.67), WSP (r = –0.49), and TP (r = –0.4) were negatively associated to CF. PSA showed a negative correlation with CF (r = –0.43). Protein and gluten were the flour components that affected cookie hardness, but no significant correlation were found with pentosan or DS content. A prediction equation for CF was developed. Sucrose SRC, PSA, and DS could be used to predict 68% of the variation in cookie diameter. The cluster analysis was conducted to assess differences in flour quality parameters among genotypes based on CF. Clusters 1 and 4 were typified by lower CF (5.70 and 5.23, respectively), higher DS, pentosan content, and SRC values. Cluster 2 with a relative good CF (6.47) and Cluster 3 with the best cookie quality, high CF (7.32) and low firmness, and the lowest DS, TP, WSP content, and sucrose SRC values.     

Silymarin and its components scavenge phenylglyoxylic ketyl radicals

The antioxidant properties of silymarin and its flavanolignan components (silybin, silychristin and silydianin) were tested. Silymarin, silychristin and silydianin exhibit relatively good antioxidant effectiveness against phenylglyoxylic ketyl radicals and DPPH. The most effective scavengers of phenylglyoxylic ketyl radicals were silymarin and silychristin whereas silydianin was ca. 5-times less active than the first two compounds whereas silybin was ineffective. The scavenging properties of the studied compounds against DPPH radicals were in the same sequence: silymarin>silychristin>silydianin>silybin.     

Comanagement for aquaculture: Suggestions from a comparative study between two major production areas of milkfish in the Philippines

ABSTRACT

This study examined if, and how, comanagement is effective in controlling aquaculture industry in the municipalities of Anda and Bolinao in the province of Pangasinan, in the Philippines, the locations of two major production areas of milkfish (Chanos chanos) in the country. Institutional and community analyses conducted in these study sites revealed a unique hierarchy of resource users, as well as unique social and economic problems in aquaculture, distinct from those of capture fishery. It was also indicated that comanagement is seen as a solution for essential practices to be enforced practically and sustainably for the management of this industry. To improve aquaculture governance, it is desired that the comanagement scheme shall include not only the governments and fishers but also business operators who often have large capital and a high degree of power.     

Effect of Transglutaminase on Protein Electrophoretic Pattern of Rice,Soybean, and Rice‐Soybean Blends

The interactions taking place in composite dough containing rice flour and soybean proteins (5% w/w) in the presence of transglutaminase, an enzyme with cross‐linking activity, were studied using different electrophoretic analyses. The interaction between rice proteins and soybean proteins was intensified by the formation of new intermolecular covalent bonds catalyzed by transglutaminase and the indirect formation of disulfide bonds among proteins. The main protein fractions involved in those interactions were both β‐conglycinin and glycinin of soybean and the glutelins of the rice flour, although albumins and globulins were also cross‐linked. The addition of soybean proteins to rice flour improves the amino acid balance and they also might play an important role on the rice dough properties because soybean proteins interact with rice proteins, yielding protein aggregates of high molecular weight.     

A Greener UV and Peroxide-Based Chemical Oxygen Demand Test

Water quality assessment typically includes the determination of chemical oxygen demand (COD) by oxidation of organic matter with Cr(VI) in an acidic medium followed by digestion. Unfortunately, the required reagents are harmful and the reaction times are rather long. We investigated earlier the use of H₂O₂ as a more environmentally friendly oxidizing agent to replace the hazardous chromates. In the present study, we have furthered this possibility by incorporating the use of H₂O₂ in the presence of UV light. A protocol has been devised and tested with standards and real samples that replaces toxic Cr(VI), halves the amount of silver sulfate required, and greatly reduces the necessary reaction time, thus yielding a faster and more environmentally sound method.