Concerning the Site of Nitrogen Absorption in Rats Fed Autoclaved or Raw Soybean Oil Mea

Carroll, Hensley, and Graham (1) have concluded that much of the nitrogen absorption in rats fed raw soybean oil meal must take place in the cecum. This conclusion was reached from data showing that the apparent digestibility of raw soybean nitrogen in the terminal 20% of the small intestine was 32.65%, whereas in the feces the value was 76.96%. Values reported, for apparent digestibility of heated soybean nitrogen were 78.66% and 81.78%, respectively. This observation presented a notable advance in explaining the lower nutritive value of raw soybeans compared with autoclaved soybeans. It therefore seemed advisable to repeat this work in order to determine the validity of the observations made

The Effect Of Conditions Of Hydrolysis And Of Prolonged Heating Upon The Optical Rotation Of Sulfuric Acid Hydrolysates Of Zein

Some time ago we observed that a sulfuric acid hydrolysate of zein prepared in an autoclave at 165˚ did not support growth in young rats when it was supplemented with certain amino acids, even though the same amino acids, added to a hydrolysate prepared by refluxing, permitted moderate growth. Since the optical rotation of the autoclaved hydrolysate was lower than that of the refluxed, either destruction or racemization of essential constituents, or both, might have occurred. Loss of amino nitrogen and production of extra ammonia upon prolonged autoclaving of proteins with acids have been noted by Van Slyke (1912) and others, but simultaneous observations on optical rotation have apparently never been made. To determine whether racemization also takes place, hydrolysates of zein prepared under conditions differing widely with respect to sulfuric acid concentration, temperature, and time were examined for optical rotation, amino nitrogen content, and in some cases for ammonia content

Trypsin Inhibitor. VII. Comparative Nutritive Value of Raw and Heated Soybean Meal for Poults

I. The trypsin inhibitor contained in one-half of a lot of soybean meal was destroyed by autoclaving at 15 pounds for 20 minutes. 2. This portion of the meal when fed at a level of 24 per cent to newly hatched poults gave a significantly greater gain in five weeks than did an equal amount of meal in which the inhibitor had not been destroyed. 3. The difference in growth is attributed to the destruction of the trypsin inhibitor

Tryptophane Metabolism X. The Effect Of Feeding 1(-)-, Dl-, And D(+)-Tryptophane, D(-)And Dl-(β-3-Indolelactic Acid,(β-3-Indolepyruvic Acid, And L(-)Kynurenine Upon The Storage Of Liver Glycogen And The Urinary Output Of Kynurenic Acid, Kynurenine, And Total Acetone Bodies

The amount of tryptophane required for maintenance and growth is small (2). When an excess is supplied to some animals, kynurenic acid is excreted (3) and, under certain conditions, kynurenine also (4). Although these are quantitatively the most important of the known metabolic products of tryptophane, the amounts excreted in extensive tests in the dog and rabbit have usually accounted for less than half, more often for less than a third, of the tryptophane administered (4-6)

Threonine Deficiency in Hydrolysates of Zein Prepared by Autoclaving

In a previous paper (Borchers and Berg, 1942) we showed that autoclaving zein with sulfuric acid longer than necessary for complete hydrolysis causes destruction and racemization; either of these might account for the failure of such a hydrolysate to promote growth in young rats when substituted for a hvdrolysate, prepared by refiuxing, in a diet which produced moderate growth. It seemed to us that this deterioration in the dietary protein might well be the result primarily of essential amino acid deficiencies which could be detected and overcome by appropriate supplementation. Because threonine is known to be present in zein in relatively small amount1 and because its 2 asymmetric carbon atoms might render it more susceptible to configurational modification by racemization, a ready production of threonine deficiency was considered likely. This was confirmed; addition of threonine to an autoclave hydrolysate (heated with 10 per cent sulfuric acid for 8 hours at 165°) promoted about as rapid growth as had the reflux hydrolysate which it replaced. Longer heating at higher temperatures produced deficiencies not fully met by threonine alone

Tryptophane Metabolism X. The Effect Of Feeding 1(-)-, Dl-, And D(+)-Tryptophane, D(-)And Dl-(β-3-Indolelactic Acid,(β-3-Indolepyruvic Acid, And L(-)Kynurenine Upon The Storage Of Liver Glycogen And The Urinary Output Of Kynurenic Acid, Kynurenine, And Total Acetone Bodies

The amount of tryptophane required for maintenance and growth is small (2). When an excess is supplied to some animals, kynurenic acid is excreted (3) and, under certain conditions, kynurenine also (4). Although these are quantitatively the most important of the known metabolic products of tryptophane, the amounts excreted in extensive tests in the dog and rabbit have usually accounted for less than half, more often for less than a third, of the tryptophane administered (4-6)

Trypsin Inhibitor. V. Nutritive Value of Treated Soybean Oil Meal and Some Characteristics of the Trypsin Inhibitor in Soybeans

The marked improvement in the apparent nutritive value of soybean protein after heating has long been recognized. The fundamental cause of this improvement has never been fully understood. Furthermore, commercial soybean oil meal varies considerably in nutritive value although heat treatment is common in most processing plants. Since heating is generally regarded as deleterious to the nutritive quality of protein, the following investigations of various treatments of soybean oil meal are of particular importance in developing a soybean or soybean oil meal of maximum and uniform nutritive value

Trypsin Inhibitor. V. Nutritive Value of Treated Soybean Oil Meal and Some Characteristics of the Trypsin Inhibitor in Soybeans

The marked improvement in the apparent nutritive value of soybean protein after heating has long been recognized. The fundamental cause of this improvement has never been fully understood. Furthermore, commercial soybean oil meal varies considerably in nutritive value although heat treatment is common in most processing plants. Since heating is generally regarded as deleterious to the nutritive quality of protein, the following investigations of various treatments of soybean oil meal are of particular importance in developing a soybean or soybean oil meal of maximum and uniform nutritive value

Serotonin 2B receptor signaling is required for craniofacial morphogenesis and jaw joint formation in Xenopus

Serotonin (5-HT) is a neuromodulator that plays many different roles in adult and embryonic life. Among the 5-HT receptors, 5-HT2B is one of the key mediators of 5-HT functions during development. We used Xenopus laevis as a model system to further investigate the role of 5-HT2B in embryogenesis, focusing on craniofacial development. By means of gene gain- and loss-of-function approaches and tissue transplantation assays, we demonstrated that 5-HT2B modulates, in a cell-autonomous manner, postmigratory skeletogenic cranial neural crest cell (NCC) behavior without altering early steps of cranial NCC development and migration. 5-HT2B overexpression induced the formation of an ectopic visceral skeletal element and altered the dorsoventral patterning of the branchial arches. Loss-of-function experiments revealed that 5-HT2B signaling is necessary for jaw joint formation and for shaping the mandibular arch skeletal elements. In particular, 5-HT2B signaling is required to define and sustain the Xbap expression necessary for jaw joint formation. To shed light on the molecular identity of the transduction pathway acting downstream of 5-HT2B, we analyzed the function of phospholipase C beta 3 (PLC) in Xenopus development and showed that PLC is the effector of 5-HT2B during craniofacial development. Our results unveiled an unsuspected role of 5-HT2B in craniofacial development and contribute to our understanding of the interactive network of patterning signals that is involved in the development and evolution of the vertebrate mandibular arch

Using non-invasively collected genetic data to estimate density and population size of tigers in the Bangladesh Sundarbans

Population density is a key parameter to monitor endangered carnivores in the wild. The photographic capture-recapture method has been widely used for decades to monitor tigers, Panthera tigris, however the application of this method in the Sundarbans tiger landscape is challenging due to logistical difficulties. Therefore, we carried out molecular analyses of DNA contained in non-invasively collected genetic samples to assess the tiger population in the Bangladesh Sundarbans within a spatially explicit capture-recapture (SECR) framework. By surveying four representative sample areas totalling 1,994 km2 of the Bangladesh Sundarbans, we collected 440 suspected tiger scat and hair samples. Genetic screening of these samples provided 233 authenticated tiger samples, which we attempted to amplify at 10 highly polymorphic microsatellite loci. Of these, 105 samples were successfully amplified, representing 45 unique genotype profiles. The capture-recapture analyses of these unique genotypes within the SECR model provided a density estimate of 2.85 ± SE 0.44 tigers/100 km2 (95% CI: 1.99-3.71 tigers/100 km2) for the area sampled, and an estimate of 121 tigers (95% CI: 84-158 tigers) for the total area of the Bangladesh Sundarbans. We demonstrate that this non-invasive genetic surveillance can be an additional approach for monitoring tiger populations in a landscape where camera-trapping is challenging