Luciana Louzada Prates

Investigating molecular structures of Brassica carinata and Canola seeds as predictors to estimate protein bioavailability for ruminants by advanced non-destructive vibrational molecular spectroscopy

This study was conducted to (1) determine protein and carbohydrate molecular structure profiles and (2) quantify the relationship between structural features and protein bioavailability of newly developed carinata and canola seeds for dairy cows by using Fourier transform infrared molecular spectroscopy. Results showed similarity in protein structural makeup within the entire protein structural region between carinata and canola seeds. The highest area ratios related to structural CHO, total CHO, and cellulosic compounds were obtained for carinata seeds. Carinata and canola seeds showed similar carbohydrate and protein molecular structures by multivariate analyses. Carbohydrate molecular structure profiles were highly correlated to protein rumen degradation and intestinal digestion characteristics. In conclusion, the molecular spectroscopy can detect inherent structural characteristics in carinata and canola seeds in which carbohydrate-relative structural features are related to protein metabolism and utilization. Protein and carbohydrate spectral profiles could be used as predictors of rumen protein bioavailability in cows.

Physiochemical Characteristics and Molecular Structures for Digestible Carbohydrates of Silages

The main objectives of this study were (1) to assess the magnitude of differences among new barley silage varieties (BS) selected for varying rates of in vitro neutral detergent fiber (NDF) digestibility (ivNDFD; Cowboy BS with higher ivNDFD, Copeland BS with intermediate ivNDFD, and Xena BS with lower ivNDFD) with regard to their carbohydrate (CHO) molecular makeup, CHO chemical fractions, and rumen degradability in dairy cows in comparison with a new corn silage hybrid (Pioneer 7213R) and (2) to quantify the strength and pattern of association between the molecular structures and digestibility of carbohydrates. The carbohydrate-related molecular structure spectral data was measured using advanced vibrational molecular spectroscopy (FT/IR). In comparison to BS, corn silage showed a significantly (P < 0.05) higher level of starch and energy content and higher degradation of dry matter (DM). Cowboy BS had lower feeding value (higher indigestible fiber content and lower starch content) and lower DM degradation in the rumen compared to other BS varieties (P < 0.05). The spectral intensities of carbohydrates were significantly (P < 0.05) correlated with digestible carbohydrate content of the silages. In conclusion, the univariate approach with only one-factor consideration (ivNDFD) might not be a satisfactory method for evaluating and ranking BS quality. FT/IR molecular spectroscopy can be used to evaluate silage quality rapidly, particularly the digestible fiber content.

Relationship of carbohydrates and lignin molecular structure spectral profiles to nutrient profile in newly developed oats cultivars and barley grain

The objectives of this study were to quantify the chemical profile and the magnitude of differences in the oat and barley grain varieties developed by Crop Development Centre (CDC) in terms of Cornell Net Carbohydrate Protein System (CNCPS) carbohydrate sub-fractions: CA4 (sugars), CB1 (starch), CB2 (soluble fibre), CB3 (available neutral detergent fibre - NDF), and CC (unavailable carbohydrate); to estimate the energy values; to detect the lignin and carbohydrate (CHO) molecular structure profiles in CDC Nasser and CDC Seabiscuit oat and CDC Meredith barley grains by using Fourier transform infrared attenuated total reflectance (FTIR-ATR); to develop a model to predict nutrient supply based on CHO molecular profile. Results showed that NDF, ADF and CHO were greater (P<0.05) in oat than in barley. The starch content was greater (P<0.05) in barley than in oat. The CDC Meredith showed greater total rumen degradable carbohydrate (RDC), intestinal digestible fraction carbohydrate (FC) and lower total rumen undegradable carbohydrate (RUC). However, the estimated milk production did not differ for CDC Nasser oat and CDC Meredith barley. Lignin peak area and peak height did not differ (P>0.05) for oat and barley grains as well as non-structural CHO. However, cellulosic compounds peak area and height were greater (P<0.05) in oat than barley grains. Multiple regressions were determined to predict nutrient supply by using lignin and CHO molecular profiles. It was concluded that although there were some differences between oat and barley grains, CDC Nasser and CDC Meredith presented similarities related to chemical and molecular profiles, indicating that CDC Meredith barley could be replaced for CDC Nasser as ruminant feed. The FTIR was able to identify functional groups related to CHO molecular spectral in oat and barley grains and FTIR-ATR results could be used to predict nutrient supply in ruminant livestock systems.

Molecular Structural Changes in Alfalfa Detected by ATR-FTIR Spectroscopy in Response to Silencing of TT8 and HB12 Genes

This study investigated the spectral changes in alfalfa molecular structures induced by silencing of Transparent Testa 8 (TT8) and Homeobox 12 (HB12) genes with univariate and multivariate analyses. TT8-silenced (TT8i), HB12-silenced (HB12i) and wild type (WT) alfalfa were grown in a greenhouse under normal conditions and were harvested at early-to-mid vegetative stage. Samples were free-dried and grounded through 0.02 mm sieve for spectra collections with attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Afterwards, both univariate and multivariate analyses were conducted on amide, carbohydrate and lipid regions. Univariate results showed that silencing of TT8 and HB12 genes affected peak heights of most total carbohydrate (TC) and structural carbohydrate (STC), and structural carbohydrate area (STCA) in carbohydrate regions; and β-sheet height, amide areas, and ratios of amide I/II and α-helix/β-sheet in amide region; and symmetric CH2 (SyCH2), asymmetric CH2 (AsCH2) and (a)symmetric CH2 and CH3 area (ASCCA) in the lipid region. Multivariate analysis showed that both hierarchy cluster analysis (HCA) and principal component analysis (PCA) clearly separated WT from transgenic plants in all carbohydrate regions and (a)symmetric CH2 and CH3 (ASCC) lipid region. In the amide region, PCA separated WT, TT8i and HB12i into different groups, while HCA clustered WT into a separate group. In conclusion, silencing of TT8 and HB12 affected intrinsic molecular structures of both amide and carbohydrate profiles in alfalfa, and multivariate analyses successfully distinguished gene-silenced alfalfa from its parental WT control.

Bio-functions and molecular carbohydrate structure association study in forage with different source origins revealed using non-destructive vibrational molecular spectroscopy techniques

The objectives of this study were to: 1) investigate forage carbohydrate molecular structure profiles; 2) bio-functions in terms of CHO rumen degradation characteristics and hourly effective degradation ratio of N to OM (HEDN/OM), and 3) quantify interactive association between molecular structures, bio-functions and nutrient availability. The vibrational molecular spectroscopy was applied to investigate the structure feature on a molecular basis. Two sourced-origin alfalfa forages were used as modeled forages. The results showed that the carbohydrate molecular structure profiles were highly linked to the bio-functions in terms of rumen degradation characteristics and hourly effective degradation ratio. The molecular spectroscopic technique can be used to detect forage carbohydrate structure features on a molecular basis and can be used to study interactive association between forage molecular structure and bio-functions.

Recent Research on Inherent Molecular Structure, Physiochemical Properties, Bio-Functions of Food & Feed-Type Oats and Processing-Induced Changes Revealed with Molecular MicroSpectroscopic Techniques

ABSTRACT Avena sativa oat is a cereal widely used as human food and livestock feed. However, the low metabolized energy and the rapid rumen degradations of protein and starch have limited the use of A. sativa oat grains. To overcome this disadvantage, new A. sativa oat varieties have been developed. Additionally, heat-related processing has been performed to decrease the degradation rate and improve the absorption of amino acids in the small intestine. The nutritive value is reflected by both chemical composition and inherent molecular structure conformation. However, the traditional wet chemical analysis is not able to detect the inherent molecular structures within an intact tissue. The advanced synchrotron-radiation and globar-based molecular microspectroscopy have been developed recently and applied to study internal molecular structures and the processing induced structure changes in A. sativa oats and reveal how molecular structure changes in relation to nutrient availability. This review aimed to obtain the recent information regarding physiochemical properties, molecular structures, metabolic characteristics of protein, and the heat-induced changes in new A. sativa oat varieties. The use of the advanced vibrational molecular spectroscopy was emphasized, synchrotron- and globar-based (micro)spectroscopy, to reveal the inherent structure of A. sativa oats at cellular and molecular levels and to reveal the heat processing effect on the degradation characteristics and the protein molecular structure in A. sativa oats. The relationship between nutrient availability and protein molecular inherent structure was also presented. Information described in this review gives better insight in the physiochemical properties, molecular structure, and the heat-induced changes in A. sativa oat detected with advanced molecular spectroscopic techniques in combinination with conventional nutrition study techniques.

Evaluation of near-infrared (NIR) and Fourier transform mid-infrared (ATR-FT/MIR) spectroscopy techniques combined with chemometrics for the determination of crude protein and intestinal protein digestibility of wheat

The potential of using the near-infrared (NIR) and Fourier transform mid-infrared (ATR-FT/MIR) spectroscopy for the determination of intestinal crude protein (CP) digestibility (IPD) of wheat was evaluated. For CP, the best NIR model showed an excellent prediction performance (R2 = 0.98); the best MIR model also gave an excellent prediction performance (R2 = 0.96). Regarding to IPD, the best model obtained by NIR technique showed approximate quantitative predictive ability (R2 = 0.68), and the best model generated by MIR technique obtained similar prediction performance (R2 = 0.67). NIR models generally showed better predictive abilities than MIR models, which may be due to the MIR spectra record fundamental molecular vibrations and can be more easily affected by multiple interferences. The amide I and II bands played important roles in the development of PLS models for CP and IPD. Results from this study demonstrated the potential of using IR spectroscopy for the prediction of nutrient digestibility while more efforts are required to improve the performance of NIR and ATR-FT/MIR spectroscopy in predicting the IPD of wheat.

Application of FT/IR-ATR vibrational spectroscopy to reveal protein molecular structure of feedstock and co-products from Canadian and Chinese canola processing in relation to microorganism bio-degradation and enzyme bio-digestion

The principal objective of this study was to apply FT/IR-ATR vibrational spectroscopy to inspect the relationship between rumen dry matter (DM) and protein degradation, rumen undegraded protein (RUP) intestinal digestion and processing induced protein molecular structure changes in feedstock (canola oil seeds) and co-products (canola meal) from bio-oil processing from different crushing plants in Canada and China. The rumen DM and protein degradation, rumen undegraded protein intestinal digestion and protein molecular structure affected by bio-oil processing were examined using in situ, three step in vitro digestion and Fourier transform infrared (FT/IR) molecular spectroscopy techniques, respectively. The results showed that the protein molecular structure; α-helix height and α-helix to β-sheet height ratio had a close association with rumen DM and protein degradation and rumen undegraded protein intestinal digestibility. Multiple regression analyses showed that protein β-sheet height and α-helix to β-sheet height ratio spectral intensity can be used to predict rumen DM and protein degradation, while intestinal digestibility of rumen undegraded protein can be predicted by α-helix height and β-sheet height. In conclusion, the co-product canola meal from bio-oil processing is a good source of intestinally digestible protein. Rumen DM and protein degradation and intestinal digestibility of rumen undegraded protein are related to the protein molecular structures of the co-products affected by changes during bio-oil processing.

Effects of TT8 and HB12 Silencing on the Relations between the Molecular Structures of Alfalfa (Medicago sativa) Plants and Their Nutritional Profiles and In Vitro Gas Production

The objective of this study was to investigate the effects of silencing the TT8 and HB12 genes on the nutritive profiles and in vitro gas production of alfalfa in relation to the spectral molecular structures of alfalfa. TT8-silenced (TT8i, n = 5) and HB12-silenced (HB12i, n = 11) alfalfa were generated by RNA interference (RNAi) and grown with nontransgenic wild type controls (WT, n = 4) in a greenhouse. Alfalfa plants were harvested at early-to-mid vegetative stage. Samples were analyzed for their chemical compositions, CNCPS fractions, and in vitro gas production. Correlations and regressions of the nutritional profiles and in vitro gas production with the molecular spectral structures were also determined. The results showed that the transformed alfalfa had higher digestible fiber and lower crude protein with higher proportions of indigestible protein than WT. HB12 RNAi had lower gas production compared with those of the others. Some chemical, CNCPS, and gas-production profiles were closely correlated with spectral structures and could be well predicted from spectral parameters. In conclusion, the RNAi silencing of TT8 and HB12 in alfalfa altered the chemical, CNCPS and gas-production profiles of alfalfa, and such alterations were closely correlated with the inherent spectral structures of alfalfa.

Molecular Structure of Feeds in Relation to Nutrient Utilization and Availability in Animals: A Novel Approach

Abstract The invention and development of new research concepts, novel methodologies, and novel bioanalytical techniques are essential in advancing the animal sciences, which include feed and nutrition science. This article introduces a novel approach that shows the potential of advanced synchrotron-based bioanalytical technology for studying the effects of molecular structural changes in feeds induced by various treatments (e.g., genetic modification, gene silencing, heat-related feed processing, biofuel processing) in relation to nutrient digestion and absorption in animals. Advanced techniques based on synchrotron radiation (e.g., synchrotron radiation infrared microspectroscopy (SR-IMS) and synchrotron radiation X-ray techniques) have been developed as a fast, noninvasive, bioanalytical technology that, unlike traditional wet chemistry methods, does not damage or destroy the inherent molecular structure of the feed. The cutting-edge and advanced research tool of synchrotron light (which is a million times brighter than sunlight) can be used to explore the inherent structure of biological tissue at cellular and molecular levels at ultra-high spatial resolutions. In conclusion, the use of recently developed bioanalytical techniques based on synchrotron radiation along with common research techniques is leading to dramatic advances in animal feed and nutritional research.