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1.
J Insect Sci ; 24(4)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39095324

RESUMEN

The Entomological Society of America (ESA) Student Debates is an annual student competition at the ESA Annual Meeting organized by Student Debates Subcommittee (SDS) members of the ESA Student Affairs Committee. In conjunction with the 2023 ESA Annual Meeting theme, 'Insects and influence: Advancing entomology's impact on people and policy', the theme of this year's student debate was 'Addressing emerging issues in entomology'. With the aid of ESA membership, the SDS selected the following debate topics: (1) Should disclosure of artificial intelligence large language models in scientific writing always be required? and (2) Is it more important to prioritize honey bee or native pollinator health for long-term food security within North America? Four student teams from across the nation, composed of 3-5 student members and a professional advisor, were assigned a topic and stance. Over the course of 5 months, all team members researched and prepared for their assigned topic before debating live with an opposing team at the 2023 ESA Annual Meeting in National Harbor, Maryland. SDS members additionally prepared and presented introductions for each debate topic to provide unbiased backgrounds to the judges and audience for context in assessing teams' arguments. The result was an engaging discussion between our teams, judges, and audience members on emerging issues facing entomology and its impact on people and policy, such as scientific communication and food security, that brought attention to the complexities involved when debating topics concerning insects and influence.


Asunto(s)
Entomología , Entomología/métodos , Estudiantes , Animales , Sociedades Científicas , Inteligencia Artificial
2.
Compr Rev Food Sci Food Saf ; 18(3): 775-797, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-33336925

RESUMEN

Pulses (grain legumes) are increasingly of interest to the food industry as product formulators and consumers seek to exploit their fiber-rich and protein-rich reputation in the development of nutritionally attractive new products, particularly in the bakery, gluten-free, snack, pasta, and noodle categories. The processing of pulses into consistent high-quality ingredients starts with a well-defined and controlled milling process. However, in contrast to the extensive body of knowledge on wheat flour milling, the peer-reviewed literature on pulse flour milling is not as well defined, except for the dehulling process. This review synthesizes information on milling of leguminous commodities such as chickpea (kabuli and desi), lentil (green and red), pea, and bean (adzuki, black, cowpea, kidney, navy, pinto, and mung) from the perspective of a wheat miller to explore the extent to which pulse milling studies have addressed the objectives of wheat flour milling. These objectives are to reduce particle size (so as to facilitate ingredient miscibility), to separate components (so as to improve value and/or functionality), and to effect mechanochemical transformations (for example, to cause starch damage). Current international standards on pulse quality are examined from the perspective of their relationship to the millability of pulses (that is, grain legume properties at mill receival). The effect of pulse flour on the quality of the products they are incorporated in is examined solely from the perspective of flour quality not quantity. Finally, we identify research gaps where critical questions should be answered if pulse milling science and technology are to be established on par with their wheat flour milling counterparts.

3.
Benef Microbes ; 1(2): 197-207, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21831757

RESUMEN

The effects of diets supplemented with either chickpea or its main oligosaccharide raffinose on the composition of the faecal microbial community were examined in 12 healthy adults (18-65 years) in a randomised crossover intervention study. Subjects consumed their usual diet supplemented with soups and desserts that were unfortified, or fortified with either 200 g/d of canned chickpeas or 5 g/d of raffinose for 3 week periods. Changes in faecal bacterial populations of subjects were examined using 16S rRNA-based terminal restriction fragment length polymorphisms (T-RFLP) and clone libraries generated from the diet pools. Classification of the clone libraries and T-RFLP analysis revealed that Faecalibacterium prausnitzii, reported to be an efficient butyrate producer and a highly metabolically active bacterium in the human intestinal microbiota, was more abundant in the raffinose diet and the chickpea diet compared to the control diet. However, no significant difference was observed in the faecal total short chain fatty acid concentration or in the levels of the components (butyrate, acetate and propionate) with the chickpea diet or the raffinose diet compared to the control diet. Bifidobacterium species were detected by T-RFLP in all three diet groups and quantitative real-time PCR (qPCR) analysis showed a marginal increase in 16S rRNA gene copies of Bifidobacterium with the raffinose diet compared to control (P>0.05). The number of individuals showing TRFs for the Clostridium histolyticum - Clostridum lituseburense groups, which include pathogenic bacteria species and putrefactive bacteria, were lower in the chickpea diet compared to the other two treatments. Diet appeared to affect colonisation by a high ammonia-producing bacterial isolate which was detected in 83%, 92% and 42% of individuals in the control, raffinose and chickpea groups, respectively. Our results indicate that chickpea and raffinose have the potential to modulate the intestinal microbial composition to promote intestinal health in humans.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Biodiversidad , Cicer , Dieta/métodos , Heces/microbiología , Rafinosa/administración & dosificación , Adulto , Bacterias/genética , Análisis por Conglomerados , Estudios Cruzados , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos Volátiles/análisis , Heces/química , Humanos , Filogenia , Polimorfismo de Longitud del Fragmento de Restricción , ARN Ribosómico 16S/genética
4.
J Agric Food Chem ; 49(5): 2437-45, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368617

RESUMEN

Five rye lines exhibiting a wide range of extract viscosities, along with commercial cultivars of rye and wheat, were compared with respect to their physical and chemical properties. Rye wholemeals contained significantly higher concentrations of total and soluble dietary fiber (TDF and SDF, respectively), total and water-extractable arabinoxylan (TAX and WEAX, respectively), and beta-glucan than did wheat. Significant positive correlations were obtained between rye wholemeal extract viscosity and SDF content (r = 0.90, p < 0.05) and WEAX content (r = 0.89, p < 0.05). Gel permeation chromatography (GPC) of water extracts of rye wholemeals revealed the presence of a high molecular weight fraction (HMWF), which was found in higher concentration in the ryes than in wheat. A significant positive correlation (r = 0.84, p < 0.05) was observed between HMWF content (expressed as a proportion of the total carbohydrate in water extracts) and extract viscosity of rye wholemeals. Treatment of a rye wholemeal extract with xylanase, followed by GPC, indicated that the HMWF consisted primarily of WEAX. Successive treatment of a rye wholemeal extract with alpha-amylase, lichenase, protease, and xylanase confirmed that the viscosity of the extract was primarily related to its content of WEAX. WEAX was isolated from high, intermediate, and low extract viscosity ryes. Structural differences were observed among the three arabinoxylans using H NMR and high-pressure size exclusion chromatography with triple detection. The WEAX from high extract viscosity rye was a higher molecular weight macromolecule exhibiting a higher intrinsic viscosity, a larger radius of gyration, a larger hydrodynamic radius, and a lower degree of branching compared to WEAX from low and intermediate extract viscosity ryes.


Asunto(s)
Peso Molecular , Extractos Vegetales/análisis , Secale/química , Viscosidad , Cromatografía Líquida de Alta Presión , Fibras de la Dieta/análisis , Glucanos/análisis , Espectroscopía de Resonancia Magnética , Tamaño de la Partícula , Triticum/química , Xilanos/análisis
5.
J Agric Food Chem ; 49(5): 2446-53, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11368618

RESUMEN

Five rye lines exhibiting a wide range of extract viscosities were evaluated for the rheological and baking properties of their flours, individually and in blends with hard red spring wheat flour. Commercial cultivars of rye and triticale were included in the study as controls. Extract viscosities of rye flours were higher than those of corresponding wholemeals, indicating shifting of water-extractable arabinoxylan into flour during roller milling. Falling numbers of the rye flours correlated positively with their extract viscosities in the presence (r = 0.73, p < 0.05) or absence (r = 0.65, p < 0.05) of an enzyme inhibitor. Farinograms revealed the weakness of rye and triticale flours compared to wheat flour. Extract viscosities of rye flours were negatively correlated (r = -0.65, p < 0.05) with mixing tolerance index and positively correlated (r = 0.64, p < 0.05) with dough stability, suggesting a positive impact of extract viscosity on dough strength. Extract viscosity was negatively correlated (r = -0.74, p < 0.05) with loaf volume and specific volume (r = -0.73, p < 0.05) and positively correlated (r = 0.73, p < 0.05) with loaf weight of rye/wheat bread. Overall, the results indicated that 30% of flour from high or low extract viscosity rye could be incorporated into rye/wheat breads without seriously compromising bread quality. Inclusion of rye, particularly high extract viscosity rye, in chick diets seriously impeded growth performance and feed efficiency. Part of the arabinoxylan survived bread-making and exerted an effect on chicks, although substantially lower digesta viscosities were observed in chicks fed rye bread diets than in those fed rye wholemeals.


Asunto(s)
Secale/química , Viscosidad , Alimentación Animal , Culinaria , Harina , Valor Nutritivo , Reología , Triticum , Xilanos/análisis
6.
Poult Sci ; 76(9): 1272-7, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9276890

RESUMEN

Experiments were conducted to evaluate the nutritional value of meal derived from low glucosinolate cultivars of mustard (Brassica juncea) in comparison to samples of canola meal (Brassica napus, Brassica rapa). Samples of Brassica seed (four B. juncea, one B. napus, and one B. rapa) were processed using laboratory procedures to produce oil-extracted meals, which were examined for composition (DM basis), and nutritional value for broiler chickens as judged by nutrient retention (AMEn, ileal protein digestibility) and performance. Meals derived from B. juncea contained more CP and less total dietary fiber (TDF) on a dry basis than either B. napus or B. rapa, 45.9 vs 44.6 and 43.1% CP and 27.22 vs 29.47 and 29.67% TDF, respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) levels for B. juncea and B. rapa meals were similar to each other, but lower than those of B. napus, 12.79 and 13.20 vs 20.6% ADF, and 21.15 and 19.58 vs 29.47% NDF, respectively. Brassica juncea meals contained more glucosinolates than B. napus and B. rapa, 34.3 vs 21.8 and 25.5 mumol/g total glucosinolates, respectively. Brassica juncea meals were equal or superior to B. napus and B. rapa meals for AMEn and apparent ileal protein digestibility. Similarly, broilers fed B. juncea meals grew as quickly and converted feed to BW gain as efficiently to 21 d of age as those birds fed B. napus and B. rapa meals. Feeding meal from B. rapa reduced growth rate and gain to feed ratio. In conclusion, the nutritional value of meal from low glucosinolate mustard was equal or superior to that of canola meal samples derived from B. napus and B. rapa cultivars.


Asunto(s)
Brassica/normas , Pollos/crecimiento & desarrollo , Dieta/veterinaria , Glucosinolatos/normas , Análisis de Varianza , Animales , Brassica/química , Pollos/metabolismo , Pollos/fisiología , Fibras de la Dieta/farmacología , Metabolismo Energético/fisiología , Glucosinolatos/análisis , Masculino , Valor Nutritivo , Distribución Aleatoria , Análisis de Regresión , Semillas , Glycine max/química , Glycine max/normas
7.
Poult Sci ; 74(9): 1484-94, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7501593

RESUMEN

Two studies using broiler chicks and one using adult White Leghorn roosters were conducted to determine the influence of stachyose and raffinose (alpha-galactosides of sucrose) present in soybean meal (SBM) on the nutritional value of the meal. In Experiment 1, the addition of four levels (0, .05, .10, or .20 g/kg) of alpha-galactosidase with and without 1 g/kg of invertase to a corn-SBM diet had no effect on weight gain, feed efficiency, protein digestibility, or the digestible energy value of the feed when fed to broiler chicks. However, both enzymes decreased (P < .001) dietary AMEn. In Experiment 2, ethanol extraction and incubation of SBM with alpha-galactosidase decreased the concentrations of the alpha-galactosides of sucrose in SBM from 6.59 to .81 and 1.43%, respectively. However, when broiler chicks were fed semi-purified diets containing SBM, ethanol-extracted SBM, water-incubated SBM, or water plus alpha-galactosidase-incubated SBM, no improvements in weight gain, feed efficiency, or apparent protein digestibility were observed. There was also no improvement in TMEn when the above meals were precision fed to adult White Leghorn roosters (Experiment 3). These results indicate that the removal of up to approximately 90% of the alpha-galactosides of sucrose has no beneficial effect on the nutritional value of SBM for chickens.


Asunto(s)
Alimentación Animal , Pollos/fisiología , Galactósidos/aislamiento & purificación , Glycine max , Animales , Pollos/metabolismo , Etanol , Galactosidasas , Masculino , Valor Nutritivo , Glycine max/química , Aumento de Peso
8.
J Chromatogr ; 623(1): 186-90, 1992 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-1452628

RESUMEN

The suitability of high-resolution gas chromatography (HGRC) for the analysis of the raffinose family oligosaccharides (raffinose, stachyose, verbascose) was investigated. Aqueous methanol (80%) extracts of pea flour were dried and derivatized with either trimethylimidazole or N-methyl-bis(trifluoroacetamide). Separation of the sugar derivatives was achieved utilizing a 10-m DB5-60W capillary column. The effects of carrier gas (He) flow-rate and split ratio on resolution and reproducibility were studied. HRGC analysis was characterized by excellent resolution and satisfactory reproducibility, and proved to be a rapid, sensitive method for quantitation of oligosaccharides in pea flours.


Asunto(s)
Fabaceae/química , Oligosacáridos/análisis , Plantas Medicinales , Cromatografía de Gases/normas , Harina/análisis , Indicadores y Reactivos , Oligosacáridos/normas , Ácido Trifluoroacético , Compuestos de Trimetilsililo
9.
Plant Cell Rep ; 7(6): 410-3, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24240257

RESUMEN

Papaver somniferum L. (opium poppy) cells were elicited with a Botrytis sp. homogenate and cultured by a semi-continuous process. Elicitation induced synthesis of sanguinarine and dihydrosanguinarine. Significant release of both alkaloids into the culture medium occurred. Medium exchange at 2-day intervals enabled product recovery from spent medium and maintained culture viability. Culture growth was not inhibited by elicitor treatment necessitating sub-culture prior to re-elicitation. Re-elicited cultures displayed an increasing sensitivity (reduced growth rate, higher alkaloid yield) to the elicitor with each successive treatment and did not survive a fourth elicitation.

10.
Plant Cell Rep ; 6(6): 458-61, 1987 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24248932

RESUMEN

Young leaves from Catharanthus roseus plants contain a novel N-methyltransferase which transfers the methyl group from S-adenosyl-L-methionine specifically to position 1 of (2R, 3R)-2,3-dihydro-3-hydroxytabersonine, producing the N-methylated product. The enzyme shows a high degree of specificity toward substrates containing a reduced double bond at position 2,3 of tabersonine derivatives but the more substituted N-desmethyldeacetylvindoline did not act as a substrate. The enzyme catalyses the third last step in vindorosine and vindoline biosynthesis, and is associated with chlorophyll-containing fractions in partially purified enzyme preparations. The lack of vindoline accumulation in cell suspension cultures is correlated with the lack of expression of this enzyme activity as well as that of an acetyltransferase which catalyses the last step in vindoline biosynthesis. Neither fungal elicitor treatment of cell line #615 nor transfer to alkaloid production medium resulted in expression of these two enzyme activities, nor was either enzyme activity detected in photoautotrophic or hormone autotrophic cultures. Cell lines #200, 615-767 and 916 could not be induced to produce DAT or NMT enzyme activities.

11.
Plant Cell Rep ; 5(3): 195-8, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24248131

RESUMEN

Chlorophyllous, heterotrophic periwinkle (Catharanthus roseus (L.) G. Don) cells were capable of sustained photoautotrophic growth in sugar-free B5 medium containing naphthaleneacetic acid and kinetin when provided with a CO2-enriched atmosphere. An increase in cell fresh weight, first observed approximately 2 weeks after transfer from heterotrophic to photoautotrophic conditions, coincided with the development of maximum chlorophyll content and photosynthetic activity. Electron micrographs revealed that chloroplasts of cells cultured photoautotrophically in continuous light contained large starch granules and exhibited a less extensive thylakoid system than did periwinkle mesophyll chloroplasts. Photoautotrophic cells did not accumulate vindoline or dimeric alkaloids.

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