Nutrients In Form Research Articles

Phloem Sap and Wood Carbon Isotope Abundance (δ13C) Varies with Growth and Wood Density of Eucalyptus globulus under Nutrient Deficit and Inform Supplemental Nutrient Application

Eucalyptus globulus, commonly known as blue gum or southern blue gum, is a tall, evergreen tree endemic to southeastern Australia. E. globulus is grown extensively in plantations to improve the sustainability of timber and fibre production across Australia. Sustainable forest management practices necessitate the consideration of ‘off-site’ carbon and ecological footprints. Pursuing optimal supplemental nutrient application and maximum growth rates is therefore critical to the establishment of a sustainable timber and fibre production industry. Biological indicators that can predict growth responses are therefore of extreme value. We investigated the carbon isotope abundance of wood cellulose (δ13Ccel) in E. globulus to determine potential relationships with the carbon isotope abundance of phloem sap (δ13Cphl) where the trees were subjected to different level of nutrient availability. This study also sought to determine the effect of nutrient additions on the growth of the E. globulus and to quantify the relationship between the volumetric growth of wood and δ13Ccel. Phloem sap and wood cores were collected from trees within study plots which were subjected to seven nutrient treatments over a two-year period in a monoculture E. globulus plantation in South Australia. Phloem sap was collected using the razor blade technique and wood cores were collected using a stem borer. The carbon isotope abundance (δ13C) of phloem sap and wood grown in the radial direction of the stem were determined. The basic and dry densities of wood were determined, and their relationships with phloem and wood δ13C were established. The δ13Cphl was significantly correlated with δ13Ccel. The relationship between δ13Ccel and the wood density of the respective wood sections was significant but did not consistently show the same pattern. There was no significant variation in basic density observed along the radial direction of the stem wood of the short-rotation E. globulus trees. A positive correlation was observed between δ13Ccel and the wood basic density, but the relationship was not consistent along the radial direction of the stem. However, positive correlations were observed between δ13Ccel and the air-dry density of respective wood sections. The relationship between phloem and wood δ13C and the relationship between δ13C and wood density along the radial direction of the stem needs to be considered while monitoring forest growth under nutrient- and water-limited conditions.

Towards a low energy, stirless photobioreactor using photosynthetic motile microalgae

Microalgae have a high potential for application in different industries including renewable energy production from light and atmospheric CO2. Biotechnologies should provide high production rates while using the mass and energy resources in a restrained manner. Often, mixing and gas provision are combined to minimize the energetic requirements of photobioreactors. Recent studies suggest that bioconvective patterns naturally developed in suspensions of motile microorganisms may provide biomixing. In this paper we report a study of the phototactic response of Chlamydomonas reinhardtii to induce biomixing in a small bioreactor at macro-scale. By exploiting the phototactic mechanism, we stimulated the microalgae to swim in opposite directions repeatedly in cycles of 40 min (20′ left, 20′ right) in the photobioreactor. The resulting Phototactic Oscillatory Motion (POM) lasted 7 days and maintained an amplitude close to the width of the bioreactor. Phototaxis allowed algae to remain in suspension without the use of any mechanical stirring system. We have demonstrated that light can be controlled to effectively provide mixing and ensure access to nutrients in form of an oscillatory motion at no extra energetic costs. This strategy can replace mechanical agitation in the manner of a ‘phototactic stirring’ under certain circumstances in pursuit of energetic sobriety.

247 In Vitro Characterization of Equine Fore- and Midgut Digestion

Abstract Considerable advancements can be made in the field of equine nutrition and diet formulation, by improved feed characterization and the development of nutritional models, including in vitro models, to describe nutrient degradation. Methodologically, literature values for in vitro small intestine incubation times are widely variable ranging from 2 to 18 h. While some incubation times are selected to represent approximate mean retention times, conversely, insufficient in vitro incubation times and sampling time points could prohibit or result in inaccuracies characterizing nutrient degradability characteristics, ultimately affecting both degradability and digestion values and their use. The objective of this trial was to assess whether macronutrient degradability plateaus when digested for 2 h in a simulated gastric environment plus 8, 12, or 16 h in a simulated small intestinal environment. To replicate in vivo digestion, a pepsin-pancreatin approach was selected. The first step of this method replicates the gastric environment. Ten g of each test ingredient are weighed into beakers containing 60 mL hydrochloric acid (HCl; 0.1 M) and 0.4 g pepsin (~2,500 U/g) solution. Beakers are then covered and incubated for 2 h at 39 ℃ under constant stirring. One mL aliquots of the digestion liquid are sampled at 0, 5, 10, 20, 30 60, 90 and 120 min after the start of the gastric simulation. Before replicating intestinal digestion, samples are neutralized with sodium hydroxide and the pH is increased to 7. The second step of this method replicates the small intestinal environment. Fifty mL of pancreatin-phosphate buffer (350 U/g protease, 6,000 FIP U/g lipase, 7,500 U/g amylase) is added to the beakers, which are then covered and incubated for either 8, 12, or 16 h at 39 ℃ under constant stirring. One mL aliquots of the digestion liquid are sampled at 0, 5, 10, 20, 30 60, 90, 120, 150, 180 min and thereafter hourly up until the end of digestion (480, 720, or 960 min). Aliquot samples are analyzed for starch via a glucose assay, protein via o-phthalaldehyde assay, and lipids via gas chromatography. A model will is fit to the time point data to determine degradation rates and degradable fractions of the digested samples. Results from these analyses go beyond estimating gross nutrient and digestible nutrient values and inform on the rate of degradation of nutrients of equine feedstuffs and the impact of in vitro methodology. The resulting degradability values will be used in a mechanistic model of equine digestion which will inform precision feeding. Ultimately this will improve how we feed horses to reduce nutrient excretion into the environment and reduce the risk of metabolic conditions such as laminitis.

Roles of Micronutrients in Organic Rice Production

The role of micronutrient in organic Rice production was investigated in Ihitte Uboma LGA using Lowa and Ikperejere Rice producing plots. Organic Rice producing paddies and non-organic Rice producing paddies in Lowa and ikperejere were sampled during and after rice harvest. The sources of organic enhancement used by the farmers were poultry droppings, cow dung and pig waste which were occasionally mixed with wood shavings. And these are sources of nutrients as well as organic matter. Two (2) rice paddies in Lowa and Ikperejere area in Ihitte Uboma L.G.A in Imo state were used. Fallow (control) soil were sampled also for comparism. Samples were randomly collected from depth of 0-30cm using spade. The micronutrient investigated were Zinc, Copper, Iron and Molybdenum. AAS was used to analyze Micronutrients and physicochemical was done routinely. Rice were harvested at maturity. The findings indicated that organic rice cultivation significantly increased the concentrations of the micronutrients (Zinc, Copper, Molybdenum and Iron(40 Zn, 36 Cu, 10 Mo and 23 Fe mgkg1) elements investigated compared with the control Zn 15, Cu 12, Mo 8 and Fe 10 Mgkg1 and non-organic paddy (13 Zn, 8 Cu, 5 Mo and 8 Fe mgkg1 respectively. In all case, the nutrient levels are not below critical micro nutrient levels at which deficiency may occur. Further findings on yield indicated that organic plots performed better with mean yield value of 740 kg per hectare compared with 639 kg yield per hectare from non-organic plot. The yield advantage could be attributed to addiction of organic matter which not only supplies nutrients in forms needed by plants but also helps in water and nutrient holding and release, create site for soil biota activities and formation of chelates for micronutrients availability to plants. The soil is of moderate fertility.

Glycine betaine capped ZnO NPs eliminate oxidative stress to coriander plants grown under NaCl presence

Salinity is one of the major abiotic stresses for sustainable agriculture. The use of mineral nutrients in form of nanoparticles can be a novel strategy to fight against abiotic stresses. An in vitro study has been conducted to investigate the effect of zinc oxide nanoparticles (ZnO NPs) capped with glycine betaine (ZnOBt) on coriander plants exposed to saline (NaCl) stress. SEM and XRD analysis revealed 14.73 nm and 17.34 nm size of ZnO and ZnOBt NPs, respectively with spherical to hexagonal structures. Coriander plant length and biomass increased by the application of ZnO and ZnOBt NPs. ZnOBt NPs depicted promising results at 100 mg/L where, shoot and root length increased up to 14 cm and 13 cm, respectively as compared to plants grown under saline stress. ZnOBt NPs also increased fresh and dry weight of shoots and roots as compared to other treatments. The results depict that ZnOBt NPs mitigated stress condition. This is evident from concentration of phenolic and flavonoid contents that decreased in both roots and shoots. Free radical scavenging activity, total antioxidant capacity and total reducing power also decreased in plants by ZnOBt NPs when applied with stress. The concentration of superoxide and peroxide dismutase also decreased by application of ZnOBt NPs to salt stress plants. Glycine betaine with ZnO NPs, in conclusion, can be an effective remedy for salinity-exposed plants. These nanoparticles can be encouraged as a viable technique to overcome the detrimental effects of saline stress on plants.

Polyhydroxyalkanoates: An Exotic Gleam in the Gloomy Tale of Plastics

Polyhydroxyalkanoates (PHAs) are bio-polyesters of hydroxyalkanoates that accumulate intracellularly in case of prokaryotes, as cytoplasmic granules, under carbon rich and paucity of nitrogen, phosphorous, sulphur and oxygen where it can serve as carbon and energy source under nutrient limiting condition and/or environmental stress conditions. In adverse growth conditions, many bacteria have ability to store nutrients in form of PHA granules using their specific metabolic pathways during stationary growth phase, in the presence of high levels of carbon containing nutrient sources. Bacterial PHAs have generated attention as an alternative to petroleum derived synthetic plastics. It possesses the characteristic physico-chemical properties comparable to the synthetic plastics. These properties of PHAs can be improved by blending of PHAs with other natural polymer like starch, cellulose and semisynthetic polymers like poly lactic acids and polycaprolactones. Being eco-friendly, biodegradable and biocompatible; major PHAs such as, Polyhydroxybutyrate (PHB) and Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) have found numerous vital applications in pharmaceutical, biomedical, textile, cosmetic, agricultural, treatment of waste water and have been successfully employed for Food packaging industries. This review provides a comprehensive knowledge about the world of PHAs covering its major aspects, namely its chemical nature and structure, biosynthesis, various methods of screening of potential PHA producing bacteria along with properties, several techniques used for its recovery and further characterization.

Persistent anthropogenic legacies structure depth dependence of regenerating rooting systems and their functions

Biotically-mediated weathering helps to shape Earth’s surface. For example, plants expend carbon (C) to mobilize nutrients in forms whose relative abundances vary with depth. It thus is likely that trees’ nutrient acquisition strategies—their investment in rooting systems and exudates—may function differently following disturbance-induced changes in depth of rooting zones and soil nutrient stocks. These changes may persist across centuries. We test the hypothesis that plant C allocation for nutrient acquisition is depth dependent as a function of rooting system development and relative abundances of organic vs. mineral nutrient stocks. We further posit that patterns of belowground C allocation to nutrient acquisition reveal anthropogenic signatures through many decades of forest regeneration. To test this idea, we examined fine root abundances and rooting system C in organic acid exudates and exo-enzymes in tandem with depth distributions of organically- and mineral-bound P stocks. Our design permitted us to estimate C tradeoffs between organic vs. mineral nutrient benefits in paired forests with many similar aboveground traits but different ages: post-agricultural mixed-pine forests and older reference hardwoods. Fine roots were more abundant throughout the upper 2 m in reference forest soils than in regenerating stands. Rooting systems in all forests exhibited depth-dependent C allocations to nutrient acquisition reflecting relative abundances of organic vs. mineral bound P stocks. Further, organic vs. mineral stocks underwent redistribution with historic land use, producing distinct ecosystem nutritional economies. In reference forests, rooting systems are allocating C to relatively deep fine roots and low-C exudation strategies that can increase mobility of mineral-bound P stocks. Regenerating forests exhibit relatively shallower fine root distributions and more diverse exudation strategies reflecting more variable nutrient stocks. We observed these disparities in rooting systems’ depth and nutritional mechanisms even though the regenerating forests have attained aboveground biomass stocks similar to those in reference hardwood forests. These distinctions offer plausible belowground mechanisms for observations of continued C sink strength in relatively old forests, and have implications for soil C fates and soil development on timescales relevant to human lifetimes. As such, depth-dependent nutrient returns on plant C investments represent a subtle but consequential signal of the Anthropocene.

English

The importance of vitamin A and other carotenoids in controlling micronutrient based deficiencies in particular VAD has been emphasized in recent years. This has resulted into demands for availing these nutrients in forms that are easily accessible for most of the populations in micronutrient deficient areas. Specifically in Africa, various programs have been instituted to bio-fortify crops with nutrients with more emphasis being put on Vitamin A fortification. Much as advances have been made in this area, a number of programs have registered little success while others have not taken off.  In this review, advances in breeding for vitamin A increments are discussed. Countries where successes have been achieved are also highlighted while efforts in a number of areas for the different staple crops have been given due emphasis. In particular, breeding strategies have been discussed, and examples of successful breeding strategies highlighted to inform future efforts. In addition, the effect of processing on retention of vitamin A in processed products has been discussed with specific recommendations on identification of crop specific processing procedures. Such procedures should be optimized before adoption to allow for minimal losses in vitamin A and other related nutrients. We conclude that much as advances have been made, specific efforts are still needed in certain staples in order to provide benefits to the African consumers. Key Words: African staples, Carotenoids, Malnutrition, Biofortification, Retention &nbsp

Nitrogen retention of biochar derived from different feedstocks at variable pyrolysis temperatures

Pyrolysis temperature is known to affect the potential of biochar as a nutrient-holding soil amendment, but the mechanism is unclear. In this study, physiochemical properties of biochar derived from switchgrass, water oak and biosolid at different pyrolysis temperatures were characterized using multiple techniques. In addition, biochar sorption of nitrogen nutrients in forms of ammonium (NH4+), nitrite (NO2−) and nitrate (NO3−) was investigated. The results indicated that the profound effects of pyrolysis temperature on biochar physiochemical properties were feedstock-specific. Similarly, biochar derived from different feedstocks at different temperatures exhibited different strengths to retain NH4+, NO2− and NO3−. The maximum NH4+ retention capacities were found with the biochar of switchgrass produced at 800 °C (10.47 mg g−1), biochar of water oak at 400 °C (3.82 mg g−1), and raw biosolids (43.29 mg g−1). Meanwhile, biochar was found to have limited (switchgrass and water oak) and negative (biosolids) retention for NO2− and NO3−. The cation exchange capacity (CEC) and morphological characteristics (e.g., porosity) were found to be the predominant factors affecting biochar NH4+ sorption.

Combined Precipitation/Flocculation Method for Nutrient Recovery from Greenhouse Wastewater

Phosphorus (P) pollution from greenhouse wastewater is currently a major issue. A treatment method that can efficiently remove P concentrations ([P]) that fluctuate between greenhouse systems and throughout the year is required. An ideal method would also recover nutrients in a reuseable form. A combined precipitation/flocculation process incorporating addition of lime and a biodegradable flocculant (guar gum, cationic starch, or chitosan) was investigated for providing optimized P removal and recovery. Effectiveness of this process was evaluated in simulated wastewater of low and high alkalinity, as well as real greenhouse wastewater. Precipitation via lime addition reduced total P to below 1 mg·L−1 in low-alkalinity simulated wastewater, but high alkalinity slightly inhibited separation. This inhibition was overcome by flocculation via guar gum or cationic starch addition, which improved separation efficiency and reduced separation time, although chitosan was ineffective as a flocculant. The precipitation/flocculation method was found to be effective for treating real greenhouse wastewater, although effectiveness varied with variation in wastewater composition. Recovered precipitate contained 57.4 g·kg−1 P as well as high levels of Ca, Mg, K, Fe, and Zn. This study demonstrates a P separation process incorporating lime and biodegradable flocculants could provide a means of reducing P in greenhouse wastewater below a 1 mg·L−1 regulatory limit in a settling time of less than 30 minutes, while simultaneously recovering P and other nutrients in a form that could be reused as fertilizer. An evaluation of viability of full-scale application of this technology is now warranted.

Willow bed fertigated with domestic wastewater to recover nutrients in subarctic climates

Conventional methods for wastewater treatment emphasise protecting human health, receiving waters and the environment. Consequently, they are generally designed to reduce pollutant levels and are not well-suited for creating resources. This paper describes a new, more sustainable and energy-efficient approach to wastewater treatment that satisfies health and environmental standards while also facilitating resource recovery. A full-scale compact willow bed was intensively fertigated with domestic wastewater in a cold climate to examine biomass production, the recovery of nutrients in willow biomass, and wastewater treatment. The performance of the willow bed was assessed for two years, covering three growing seasons. The studied frost-tolerant willow clones produced good biomass yields per unit area (6–7ton dry matter/ha and year) under intensive fertigation with dense planting and continuous harvesting. The biomass yield of willow species exhibiting vertical growth seemed to be greater than that for lateral growth species in the dense stands studied. In contrast to biomass production, nutrient recovery was facilitated by intensive fertigation, continuous harvesting and less dense planting with a horizontally growing willow clone. The estimated nitrogen accumulation in above-ground biomass was 210kg/ha and that of phosphorus was 30kg/ha. 90% of the accumulated nutrients in the above-ground biomass were removed from the site during the experimental period. However, the quantity of nutrients accumulated in the willow biomass represented only a small fraction of the loaded or removed amount. The willow bed was shown to be an efficient prefilter for reducing the abundance of particulate and organic matter, leaving the bulk of the remaining nutrients in forms that could be recovered in subsequent treatment steps.

Responses of extracellular enzymes to simple and complex nutrient inputs

Soil microbes produce extracellular enzymes that mineralize organic matter and release carbon and nutrients in forms that can be assimilated. Economic theories of microbial metabolism predict that enzyme production should increase when simple nutrients are scarce and complex nutrients are abundant; however, resource limitation could also constrain enzyme production. We tested these hypotheses by monitoring enzyme activities and nutrient pools in soil incubations with added simple and complex nutrient compounds. Over 28 days of incubation, we found that an enzyme's activity increased when its target nutrient was present in complex but not simple form, and carbon and nitrogen were available. β-Glucosidase and acid phosphatase activities also increased in treatments where only carbon and nitrogen were added. Glycine aminopeptidase and acid phosphatase activities declined in response to ammonium and phosphate additions, respectively. In some cases, mineralization responses paralleled changes in enzyme activity—for example, β-glucosidase activity increased and respiration was 5-fold greater in soil incubations with added cellulose, ammonium, and phosphate. However, a doubling of acid phosphatase activity in response to collagen addition was not associated with any changes in phosphorus mineralization. Our results indicate that microbes produce enzymes according to ‘economic rules’, but a substantial pool of mineral stabilized or constitutive enzymes mediates this response. Enzyme allocation patterns reflect microbial nutrient demands and may allow microbes to acquire limiting nutrients from complex substrates available in the soil.

Effects of vermicomposts and composts on plant growth in horticultural container media and soil

Summary Vermicomposts, which are produced by the fragmentation of organic wastes by earthworms, have a fine particulate structure and contain nutrients in forms that are readily available for plant uptake. In greenhouse trials, the growth of marigold and tomato seedlings, in a commercial horticultural potting medium (Metro-Mix 360), was enhanced significantly upon substitution of Metro-Mix 360 with 10% or 20% vermicomposted pig solids or vermicomposted food wastes, when all required nutrients were supplied. Same enhancement in marigold and tomato seedlings' growth occurred also upon substitution of Metro-Mix 360 with composted biosolids, but not with leaf compost. The shoot dry weights of raspberry plants, grown in a mineral soil mixed with vermicomposted pig wastes weighed more than those grown in unfertilized control soil, and were as great as those in soil receiving a complete fertilizer treatment. By comparison, raspberry shoot growth in soils amended with yard, leaf or bark composts, was poorer than that in the unfertilized control soil. Amending the soil with 4% chicken manure compost killed most of the raspberry plants. However, plant mortality was reduced and growth restored when the chicken manure compost was mixed with vermicomposted pig solids, but not with bark or yard composts. Plant growth in soils containing a mixture of chicken manure compost with 20% vermicomposted pig wastes was similar to that of plants grown in the unfertilized control. Our results showed that vermicomposts have the potential for improving plant growth when added to greenhouse container media or soil. However, there seem to be distinct differences between specific vermicomposts and composts in terms of their nutrient contents, the nature of their microbial communities, and their effects on plant growth.

8 - Supplemental Nutrition and Digestive Disease

Nutrition is an antegral part of medical management and patient care. The goal of nutritional therapy is to provide nutrients in form and amount appropriate to patients' needs. Dietary modification and application of available nutritional supplements in digestive disorders should be based upon an appreciation of the fundamental pathophysiological derangements and tailored to restore optimal gastrointestinal function.