Evaluation of the metabolizable energy value for growing lambs of the Mucuna pruriens seed and the whole pod

Whole pod and seeds of velvet bean (Mucuna pruriens) were included in diets for growing sheep used to validate previously estimated ME values of 9.7 MJ and 12.6 MJ for whole pod and seed respectively. Twenty-four lambs, 15 females and nine males of 18.7 ± 2.4 kg average weight, were allocated in three treatments using a completely randomized block design with eight replicates per treatment. Each group was given a diet with a ratio of 60% of Napier grass (Pennisetum purpureum) and 40% of a supplement with the addition of 0%, 50% whole pod or 66% of M. pruriens seeds, for TI, TII and TIII respectively. Diets were formulated to meet the requirements for 100-g daily live weight gain (LWG). The total dry matter intake (836 g a⁻¹ d⁻¹, forage + supplement), LWG (90 g a⁻¹ d⁻¹) and feed conversion (9.66 kg DM/kg LWG) of lambs from TIII were lower (P < 0.05) compared to 941 g, 121 g, and 7.78 kg DM/kg LWG from TII and 976 g, 132 g and 7.50 kg DM/kg LWG from TI respectively. No difference was found (P > 0.05) between TI and TII in the three evaluated variables. The ME values of whole pod and seeds of M. pruriens used in this work were validated. It was concluded that M. pruriens can be included as a component in diets for growing sheep, as a partial replacement of conventional feedstuffs.     

Concentration of Bioactive Compounds from Elderberry (<Emphasis Type="Italic">Sambucus nigra</Emphasis> L.) Juice by Nanofiltration Membranes

For the first time the chemical profile, physico-chemical parameters, inhibition of carbohydrate hydrolysing enzymes associated with type 2 diabetes, and radical scavenging properties of Sambucus nigra L. (elderberry) juice treated by nanofiltration (NF) were investigated. Three commercial NF membranes with different molecular weight cut-off (MWCO) (400 and 1000 Da) and polymeric material (composite fluoro-polymer and polyethersulphone) were tested. According to HPLC analyses, most part of bioactive compounds were retained by the NF membranes producing a retentate fraction of interest for the production of functional foods. The NP030 membrane, a polyethersulphone membrane with a MWCO of 400 Da, exhibited the highest rejection towards phenolic compounds when compared with the other selected membranes. Accordingly, the produced retentate fractions exhibited the highest radical scavenging activity.     

Peptides from Chia Present Antibacterial Activity and Inhibit Cholesterol Synthesis

In previous studies, it has not been reported that protein isolated from chia interferes favorably with antibacterial activity, and reduces cholesterol synthesis. The objective of this study was to determine whether commonly used commercial microbial proteases can be utilized to generate chia protein-based antibacterial and hypocholesterolemic hydrolysates/peptides, considering the effects of protein extraction method. Alcalase, Flavourzyme and sequential Alcalase-Flavourzyme were used to produce hydrolysates from chia protein (CF), protein-rich fraction (PRF) and chia protein concentrates (CPC1 and CPC2). These hydrolysates were evaluated for their antimicrobial activity against Gram-positive (G⁺) and Gram-negative (G^?) microorganisms. The protein hydrolysates were purified by ultrafiltration through a membrane with 3 kDa nominal molecular weight, for evaluation of hypocholesterolemic activity. An inhibition zone was observed when the hydrolysate was tested against S. aureus, and minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values were obtained. Peptides from chia protein with molecular mass lower than 3 kDa reduced up to 80.7% of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) enzymatic reaction velocity. It was also observed that, independent of the method used to obtain chia proteins, the fractions showed relevant bioactivity. Moreover, the intensity of the bioactivity varied with the method for obtaining the protein and with the enzyme used in the hydrolysis process. This is the first report to demonstrate that chia peptides are able to inhibit cholesterol homeostasis.     

Elevated CO2 reduces whole transpiration and substantially improves root production of cassava grown under water deficit

We evaluated the possibility of elevated CO₂ concentration ([CO₂]) to reduce the negative effect of drought on growth and physiological parameters of cassava (Manihot esculenta Crantz). Plants were grown with 390 ppm or 750 ppm of CO₂, under well-watered or under water deficit conditions. The study was conducted in a climate-controlled greenhouse using 14 L pots, for 100 days. For any value of fraction of transpirable soil water (FTSW) the carbon assimilation was always higher for plants grown under elevated [CO₂]. Still, elevated [CO₂] reduced the negative effect of drought on transpiration, water use efficiency, all growth measures and harvest index. Elevated [CO₂] increased the dry matter of tuber roots (DMTR) of well-watered plants by 17.4%. The DMTR of plants grown under water deficit were 124.4 g and 58.9 g, respectively, for plants under elevated and ambient CO₂, an increase of 112%. Thus, the CO₂ effect was relatively stronger to the production of tuberous roots when cassava were subjected to water-deficit. Our results suggest that cassava tuber production might be resilient to changes in precipitation that will accompany higher atmospheric CO₂ and reinforce cassava as a specie that can significantly contribute to mitigate hunger in a changing climate environment.     

Assessing uncertainty of semi‐intensive production of whiteleg shrimp (Litopenaeus vannamei) using partial harvesting programs

We used stochastic models for analysis of the uncertainty involved in semi‐intensive production of shrimp in Nayarit state, Mexico, incorporating partial harvests. Analysis of the database showed that increasing the number of harvests was associated with lower stocking densities, the use of larger ponds, longer cultivation periods, larger final weight of shrimp and total production. Equivalence tests showed that the models adequately fitted the primary data. Monte Carlo simulations indicated that improving management by controlling stocking density and the duration of cultivation increased mean production from 981 to 2573 kg/ha (one partial harvest), from 1808 to 3602 kg/ha (two partial harvests) and from 1364 to 3834 kg/ha (three partial harvests), closely approaching the yields reported in the database. When conducting one and three partial harvests, improved management increased production and the certainty in obtaining the crops, as indicated by diminishing values of the coefficient of variation in output probability distributions. When conducting two partial harvests, however, improved management increased yields, but also increased uncertainty because there was a lower control on production parameters. This does not necessarily imply more uncertainty when conducting two harvests, but that at this stage of knowledge, the primary data only allows detecting limited control on production. Results of a preliminary economic evaluation showed that net revenues ranged from USD$ 2361.1–3488.9, the benefit‐cost ratio from 1.47 to 1.62 and that the best and worse results were obtained by conducting two and one partial harvests. We conclude that the models are useful for analysing uncertainty of semi‐intensive shrimp production incorporating partial harvesting.     

Effects of biosolarization as methyl bromide alternative for <Emphasis Type="Italic">Meloidogyne incognita</Emphasis> control on quality of soil under pepper

The Adenosine triphosphate (ATP) content, dehydrogenase, phosphatase, urease, and β-glucosidase activity decreased after manure amendment plus solarization (biosolarization), but they recovered after cropping, reaching levels higher than or similar to those before the biosolarization. However, these biochemical parameters decreased and did not recover with time in the methyl bromide (MeBr) treatment. Potential negative soil effects were assayed by measuring, ecotoxicity (Vibrio fisheri luminescence), germination index, electrical conductivity, and heavy metals content. Biosolarization did not negatively affect these parameters, while MeBr application irreversibly decreased the germination index and ecotoxicity. Higher-quality pepper production (extra and first class) were observed with biosolarization but not with MeBr, but no differences were found for pepper yield. Biosolarization gave a Meloidogyne incognita (M. incognita) incidence similar to that of MeBr application.     

Effects of grain angle on the amplitudes of acoustic emission and surface roughness in wood machining

The orientation of wood fibers and the resulting surface roughness of radiata pine are studied during a peripheral milling with acoustic emission control. Studies were undertaken in machining process for radiata pine, where a surface quality problem appears when cutting is not well controlled. It is known that acoustic emission signals are a good monitoring element of the surface roughness with different cutting conditions. Previous studies have shown that changing cutting conditions affects acoustic emission signals; these variations are related to surface roughness and chip formation. The purpose of this study is to evaluate and quantify the surface quality and the consumption of cutting energy in radiata pine with differing grain angles, and to determine the relationships of grain angle with acoustic emission signals in order to better optimize cutting conditions.     

Effects of addition of Navicula sp. (diatom) in different densities to postlarvae of shrimp Litopenaeus vannamei reared in a BFT system: Growth,survival, productivity and fatty acid profile

The objective of this study was to evaluate the effect of the addition of Navicula sp. on the growth and fatty acids profile of Litopenaeus vannamei postlarvae in a biofloc system (BFT). Four treatments were used: BFT; BFT 2.5N (addition of 2.5 × 10⁴ cells/ml of Navicula sp.); BFT 5N (addition of 5 × 10⁴ cells/ml of Navicula sp.) and BFT 10N (addition of 10 × 10⁴ cells/ml of Navicula sp.), all in triplicate. The shrimp (1 ± 0.01 mg) were stocked at a density of 3,000 postlarvae/m³ and fed with commercial feed. The diatom was added every 10 days, and at the end of 42 days, shrimp performance, water quality and proximal composition were evaluated. The BFT 5N and BFT 10N treatments had higher performance values, highlighting the values of productivity (2.30 and 2.42 kg/m³) and specific growth rate (15.92 and 16.08%/day), which were higher than the other treatments. In addition, the highest levels of fatty acids were observed in treatments with diatom (BFT 5N and BFT 10N), indicating the benefits of Navicula sp. on growth enhancement and fatty acid content of L. vannamei postlarvae grown in biofloc systems.