Showing papers on "Amylase published in 1978"
TL;DR: It is concluded that the decreased response (desensitization) is a postreceptor phenomenon and possibly mediated by Ca2+ itself.
Abstract: Isolated pancreatic acini were prepared by a new method from mouse and rat pancreases by digestion with purified collagenase and chymotrypsin followed by mechanical shearing. Acini were structurally similar to those of the intact pancreas, having a normal luminal structure but with the basal acinar cell membranes exposed to the incubation medium. Amylase release in response to both cholinergic analogues and the cholecystokinin analogues caerulein and pentagastrin was comparable to that of the intact pancreas, but was much greater than previously reported for isolated acinar cells. Cholinergic-stimulated release was inhibited by atropine with a Ki value of 1.4 nM which is comparable to other muscarinic receptors. All agonists tested, when added at supramaximal concentrations, produced a submaximal release of amylase even though ATP levels and the release of slowly exchanging 45Ca2+ were normal or increased. Acini releasing amylase submaximally after being exposed to supramaximal concentrations of carbachol failed to respond to a maximal amount of caerulein or to the Ca2+ ionophore A23187. It is concluded that the decreased response (desensitization) is a postreceptor phenomenon and possibly mediated by Ca2+ itself.
408 citations
TL;DR: Investigation of the pathway of starch breakdown in the photosynthetic tissues of Pisum sativum showed that starch was rapidly metabolized in the dark at rates of 0.04--0.06 mumol glucose/min per g fresh weight, and it was proposed that starch Breakdown in pea chloroplasts is phosphorolytic.
226 citations
TL;DR: When incubated with a secretagogue such as cholecystokinin (CCK), dispersed acini prepared from guinea pig pancreas released substantially more amylase than did dispersed single acinar cells.
Abstract: When incubated with a secretagogue such as cholecystokinin (CCK), dispersed acini prepared from guinea pig pancreas released substantially more amylase than did dispersed single acinar cells. With CCK the rate of amylase release from dispersed acini decreased after 5 min of incubation and remained constant for the subsequent 25 min. The magnitude of the reduction in the rate of amylase release after 5 min was greater with higher concentrations of CCK. With vasoactive intestinal peptide (VIP), the rate of amylase release remained constant for at least 30 min. With CCK plus VIP, potentiation of the rate of amylase release occurred only during the first 15 min of incubation. After 15 min of incubation, the effects of the two peptides were additive. When dispersed acini were first incubated with CCK, potentiation of amylase release occurred only when VIP was added during the initial 10 min of incubation. In contrast, when cells were first incubated with VIP, potentiation of amylase release occurred when CCK was added as long as 30 min after VIP.
162 citations
TL;DR: The changes with age of intestinal mucosa, protein, lactase, maltase and sucrase were followed in the piglet between day 105 of gestation and 8 weeks after birth.
Abstract: The development of pancreatic tissue (fresh weight, total proteins, RNA and DNA) and of the level of pancreatic enzymes (trypsin, chymotrypsin, lipase and amylase) of the piglet has been followed from birth to the age of 8 weeks in 10 animals at each of 7 stages. There was an increase with age and body weight of the total fresh weight of the exocrine pancreas. From birth until 4 weeks the development of the pancreatic gland was due to hyperplasia; from the 4th week till the 8th week of age, it was due both to hyperplasia and hypertrophy. There was a specific period, at the age of 3--4 weeks, from which total enzymatic activities markedly increased. Furthermore, from the 4th week of age there was a rise in the intake of total dietary proteins, fat and carbohydrates, due to the intake of solid food.
130 citations
TL;DR: Red kidney bean contains more amylase inhibitor than do California white bean and cowpea while garbanzo bean and Westan and Westley lima beans do not contain inhibitor, which is high in aspartic acid, glutamic acid, serine, threonine and valine, and low in cysteine/cystine.
Abstract: Red kidney bean contains more amylase inhibitor than do California white bean and cowpea while garbanzo bean and Westan and Westley lima beans do not contain inhibitor. Red kidney bean amylase inhibitor was purified to homogeneity by selective heat treatment (60°C) of a water extract at pH 4. 0, fractionation with ethanol and successive chromatography on DEAE- and CM-cellulose chromatography. The inhibitor has an apparent molecular weight of 49,000 by Sephadex gel filtration and contains 8. 6% carbohydrate probably covalently linked via an amide linkage to asparagine. The inhibitor probably contains four subunits perhaps of three different types. The inhibitor is high in aspartic acid, glutamic acid, serine, threonine and valine, low in cysteine/cystine and does not contain proline. Stable 1:1 complex formation between inhibitor and porcine pancreatic α-amylase was demonstrated by gel filtration on Sephadex G-100. The inhibitor has activity against porcine pancreatic α-amylase, human salivary α-amylase, and Tenebrio molitor (yellow corn meal worm) larval midgut α-amylase but is inactive against Bacillus subtilis α-amylase, Aspergillus oryzae α-amylase, barley α-amylase and red kidney bean α-amylase.
82 citations
Patent•
13 Oct 1978
TL;DR: In this paper, a process for the preparation of hydrolyzed products from whole grain, and such derived products are used as a sweetening agent in food products as bread, drinks, and cereal products, whereby the bran obtained can be used in bread as fiber additive.
Abstract: The present invention relates to a process for the preparation of hydrolyzed products from whole grain, and such derived products. The invention solves the problem of obtaining a protein and sugar containing product able to be filtrated whereby this is achieved by treating whole grain, such as wheat, maize, rye, barley, oat, and rice, with a proteolytic enzyme to transform water insoluble proteins into watersoluble products, and further to treat the starch contents with an amylase free from other carbohydrate hydrolyzing enzymes to form water-soluble starch products, as mono and disaccharides, removing the bran fraction and removing water to obtain a dry, semimoist, or liquid but concentrated derived product. The product is to be added as a sweetening agent in food products as bread, drinks, and cereal products, whereby the bran obtained can be used in bread as fiber additive.
81 citations
TL;DR: P -Nitrophenyl maltotrioside and maltotetraoside were shown to be the higher homologues of klebsiella pneumoniae transferase and are very good substrates for human and pig-pancreatic alpha amylase.
78 citations
TL;DR: An α-amylase, found in the culture filtrate of a strain of Thermoactinomyces vulgaris, was purified by ammonium sulfate fractionation, and DEAE-cellulose and CM- cellulose chromatographies and showed a single band on disc gel electrophoresis.
Abstract: An α-amylase[α-l,4-glucan 4-glucanohydrolase, EC 3.2.1.1.], found in the culture filtrate of a strain of Thermoactinomyces vulgaris, was purified by ammonium sulfate fractionation, and DEAE-cellulose and CM-cellulose chromatographies. The purified enzyme showed a single band on disc gel electrophoresis. The optimum reaction pH and temperature were determined to be around pH 5.0 and 70°C. The isoelectric point was determined to be pH 5.2. The α-amylase was stabilized by Ca2+.The α-amylase was found to hydrolyze pullulan to panose. Therefore, the hydrolytic pattern of this enzyme is different from those of pullulanase and isopullulanase.
61 citations
TL;DR: The results suggest the existence of an endocrine-exocrine relationship in the pancreas in juvenile-onset diabetics, and suggest that 9 patients had residual insulin secretion.
Abstract: Residual beta cell function was studied in 18 juvenile-onset diabetics by measuring serum C-peptide immunoreactivity (CPR) fasting, and after IV injection of glucagon (1 mg). This was compared with the exocrine pancreatic response to an IV infusion of secretin and cholecystokinin-pancreozymin. Outputs of pancreatic bicarbonate, amylase and trypsin were measured. Exocrine secretory pancreatic function was decreased in 14 patients. Fasting and maximal CPR showed that 9 patients had residual insulin secretion. For these ‘CPR-secretors’ there was a strong correlation between CPR and output of bicarbonate (r = 0.87, p < 0.005) and amylase (r =0.7, p < 0.05), but not with trypsin. These results suggest the existence of an endocrine-exocrine relationship in the pancreas.
60 citations
TL;DR: The characteristics of some new α-amylases and factors regulating the biosynthesis of starch hydrolyzing enzymes are described, which indicates the potential improvement in starch processing.
Abstract: Publisher Summary This chapter describes the characteristics of some new α-amylases and factors regulating the biosynthesis of starch hydrolyzing enzymes. The bacterial α-amylases are used for liquefaction of starch to allow for the efficient production of dextrose by sacchrifying enzymes. These α-amylases are endoamylases capable of randomly hydrolyzing the α-D-( 1→4) glucosidic linkages of starch. The α-amylases are used with continuous starch cooking by direct steam contact. This type of process provides improved process control, which produces a consistent level of saccharides. Because portions of the industrial processes concerned with production of dextrose are carried out in a pH range of 4.0–5.0, an advantage can be obtained with an acidophilic liquefying amylase, that is, the existence of these types of enzymes indicates the potential improvement in starch processing. The growth cycle of bacteria that produce amylases can be divided into three important phases: the trophophase—in which the potentially productive biomass is produced, the idiophase—in which the amylase is produced, and the transition phase—that separates the first two phases.
56 citations
TL;DR: It was concluded that the exocrine proteins are stored in two pools in which the proportions of enzymes are different and with the help of a mathematical model it is proposed that one pool which corresponds to less than 0.35% of total enzyme storage, is responsible for basal secretion and is not sensitive to stimulation.
Abstract: 1. The relative variations of rat pancreatic amylase versus lipase and chymotrypsinogen secretions have been studied in vitro with the help of two different techniques: in situ organ perfusion and incubation of pancreatic lobules. 2. In experiments on the perfused pancreas, with 8 C u.kg-1 hr-1 secretin added to the perfusion fluid, cholecystokinin-pancreozymin (8 ID u.kg-1) or pilocarpine (15 mg kg-1) both resulted in a significant change in the enzyme proportions in the juice. 3. In experiments on pancreatic lobules, the addition to the incubation medium of secretin (10(-7) M), alone or associated with cholecystokinin-pancreozymin (8 x 10(-7) M) or pilocarpine (10(-4) M) did not induce any change in the enzyme proportions in secretion. 4. It was concluded that the non-parallelism between enzyme secretions can occur in the rat upon pancreozyminic or cholinergic stimulation in vitro as well as in vivo (Dagorn, 1978) provided basal protein output is low enough. This is not the case when the tissular integrity of the pancreas is lost, such as in experiments on lobules. 5. This work confirms that pancreatic secretion derives from two intrapancreatic pools of different enzymatic composition, and gives a possible explanation for some discrepancies from the literature on the existence of non-parallel secretion.
TL;DR: The experiments with maltose and trypsinized amylase suggest the inhibitor may not bind at the active site of α-amylase, suggesting a rate-controlling conformational change.
Abstract: Purified red kidney bean (Phaseolus vulgaris) amylase inhibitor forms a 1:1 stoichiometric complex with porcine pancreatic α-amylase leading to complete loss of enzyme activity on starch. Rate of complex formation is pH dependent and is maximal at pH 5. The rate constants for complex formation, as measured by loss of amylase activity, were 2.85 × 104 M-1 sec-1 at pH 6.9 (ionic strength of 0.918) and 2.55 × 105 M-1 sec-1 at pH 5 at 30°C. At pH 6.9, rate of complex formation was 4.8 times faster at 0.918 ionic strength as compared with the rate at 0.138 ionic strength. At 30°C, pH 6.9 and ionic strength of 0.168 the dissociation constant of the enzyme-inhibitor complex was determined to be 3.5 × 10-11 M. The rate constant for dissociation of the complex was calculated to be 8.7 × 10-8 sec-1 under the same conditions. The rate constant for complex formation, at ionic strength of 0.168, was 1.1 × 104 M-1 sec-1 at 370 and 9.77 × 102 M-1 sec-1 at 25.7°C. The calculated activation energy for complex formation is 39.5 kcal/mole suggesting a rate-controlling conformational change. Oxidation of the carbohydrate moiety of the glycoprotein inhibitor caused complete loss of activity. Maltose, a competitive inhibitor of α-amylase, bound as readily to the enzyme-inhibitor complex as to free α-amylase. Trypsinized α-amylase, although still able to bind to Sephadex, did not bind inhibitor. The experiments with maltose and trypsinized amylase suggest the inhibitor may not bind at the active site of α-amylase.
TL;DR: A moderately halophilic Acinetobacter sp.
Abstract: A moderately halophilic Acinetobacter sp., capable of producing dextrinogenic amylase, was isolated from sea-sands. Maximum enzyme production was obtained when the bacterium was cultivated aerobica...
TL;DR: The radioprotective capacity of the chemoprotector WR-2721 was assessed in the rat parotid gland using gland weight and amylase content as the indicators of effect over the 9-day period following x irradiation with 1, 3, and 6.4 kR of acute x rays.
Abstract: The radioprotective capacity of the chemoprotector WR-2721 was assessed in the rat parotid gland using gland weight and amylase content as the indicators of effect over the 9-day period following x irradiation with 1.6, 3.2, and 6.4 kR of acute x rays. The decline and recovery of weights and amylase content were measured and compared in animals which had and had not received WR-2721 just prior to irradiation. Analysis of the dose-response curves for the WR-2721 protected vs nonprotected animals yielded dose modification factors of 2.5 for gland weight, 1.7 for amylase concentration, and 1.8 for total gland amylase. Thus, WR-2721 was found to be effective in yet another tissue and to a degree consistent with that of other organs and systems.
TL;DR: The effects of the glucocorticoid, dexamethasone, and the thymidine analog, Q-bromodeoxyuridine (BrdUrd), on steady state levels of the predominant mRNAs during in vitro development of 14-day pan- creatic rudiments were examined and identified as pancreatic amylase mRNA by the thermal stability of the cDNA-RNA hybrids.
01 Mar 1978
TL;DR: A β-amylase and a pullulanase produced by Bacillus cereus var.
Abstract: A β-amylase and a pullulanase produced by Bacillus cereus var. mycoides were purified by means of ammonium sulfate fractionation, adsorption on starch and celite and Sephadex G–100 column chromatography. The purified enzymes were homogeneous in disc electrophoresis.The β-amylase released only maltose from amylose, amylopectin, starch and glycogen, and the released maltose was in β-form. The pullulanase released maltose, maltotriose and maltotetraose from β-limit dextrin and maltotriose from pullulan, but not amylose-like substance from amylopectin.The optimum pHs of β-amylase and pullulanase were about 7 and 6~6.5, respectively. The optimum temperatures of the enzymes were about 50°C. The enzymes were inhibited by the sulfhydryl reagents such as mercuric chloride and p-chloromercuribenzoate, and the inhibitions with p-chloromercuribenzoate were restored by the addition of cysteine. The molecular weights of β-amylase and pullulanase were estimated to be 35,000±5,000 and 110,000±20,000, respectively.
TL;DR: Isoproterenol was effective at concentrations causing amylase release in vivo and in vitro and could be blocked by the beta adrenergic antagonist propranolol, while the alpha adrenergic agonist phenylephrine did not stimulate the enzyme or increase methyl acceptor proteins.
Abstract: Protein carboxymethylase (S-adenosyl-l-methionine:protein-O-methyltransferase, EC 2.1.1.24) transfers methyl groups from S-adenosylmethionine to protein carboxyl groups. This cytosolic enzyme is found in highest concentration in secretory tissue and methylates membrane proteins. Stimulation of the parotid gland by catecholamines rapidly and reversibly increases protein carboxymethylase activity and methyl acceptor capacity of proteins in parotid homogenates. Isoproterenol was effective at concentrations causing amylase release in vivo and in vitro. Both enzyme activity and methyl acceptor capacity of proteins increased within 5 min, continued to increase for 30 min and then declined to control values within 60 min. The response to isoproterenol was stereospecific. The action of isoproterenol could be blocked by the beta adrenergic antagonist propranolol, while the alpha adrenergic agonist phenylephrine did not stimulate the enzyme or increase methyl acceptor proteins. Methyl acceptor proteins have been partially characterized by polyacrylamide gel electrophoresis. Although many proteins in the parotid are methylated, only two groups of methylated proteins increase after stimulation by isoproterenol.
TL;DR: An α-amylase inhibitor from rye (Secale cereale) flour has been purified to homogeneity by extraction with 70% ethanol, ammonium sulfate fractionation and column chromatography on DEAE- and CM-cellulose, indicating two subunits identical in size.
Abstract: An α-amylase inhibitor from rye (Secale cereale) flour has been purified to homogeneity by extraction with 70% ethanol, ammonium sulfate fractionation and column chromatography on DEAE- and CM-cellulose. The isoelectric point was pH 5.8, and the molecular weight 28,000 by polyacrylamide gel electrophoresis with different gel concentrations and 27,000 by sedimentation equilibrium centrifugation. Under denaturating conditions the molecular weight was about 14,000, indicating two subunits identical in size. The inhibitor was active towards human salivary and hog pancreatic α-amylases but inactive towards Bacillus subtilis and Aspergillus oryzae α-amylases. The pH optimum for the reaction between the rye inhibitor and human salivary α-amylase was 6.0. The inhibitor did not change activity when exposed to pH 2 (0.01M HCl), but prolonged digestion by trypsin destroyed the inhibitor. The rye α-amylase inhibitor lost about 80% of its activity after 10 min at 100°C.
TL;DR: In this article, β-amylase and α-glucosidase were compared in vitro for the digestion of starch granules in ungerminated and germinating barley grains.
Abstract: α-Amylase (EC 3.2.1.1) and β-amylase (EC 3.2.1.2) were isolated and purified, each to a state free from contaminating enzymes, from the barley malt and ungerminated barley grains, respectively. Starch granules, isolated from the same sources, served as substrates to study the mode of action of amylases on the digestion of starch granules in vitro. β-Amylase alone had a very small activity on starch granules and formed maltose as a sole digestion product. α-Amylase played a major role in the digestion of starch granules and the combined action of α- and β-amylases was more effective than the action of α-amylase alone, but was less effective, on the same enzyme activity basis, than the crude extract from barley malt, which was thought to represent in vitro the enzyme system for the digestion of starch granules in the germinating barley grains. The possible roles to be played by a debranching enzyme, α-glucosidase and/or glucosyl- or glucanotransferases are discussed.
TL;DR: Starch generally enhances amylase activities in both strains, but the ultimate effect depends on other components of the food, and the level of c~-glucosidase activity is similar for different disaccharides, but is even higher when starch is fed.
Abstract: The effects of different feeding conditions on amylase and c~-gtucosidase activities were studied in larvae and flies of Drosophila melanogaster homozygous for different amylase alleles. Starch generally enhances amylase activities in both strains, but the ultimate effect depends on other components of the food. The availability and concentration of yeast plays an important role and can have differential effects on enzyme activities of different genotypes, a-Glucosidase activities increase during adult development. These activities are higher in starving flies than in flies fed with disaccharides. The level of c~-glucosidase activity is similar for different disaccharides, but is even higher when starch is fed.
TL;DR: In this article, three major amylase components were purified to an apparent homogeneity, and band A and C were identified to be α- and β-amylase, respectively.
Abstract: During the germination of rice seed, multiple forms of amylase molecules are synthesized in the endosperm tissues as detectable by the isoelectric focusing on polyacrylamide gel. Among three major amylase components, two of them were purified to an apparent homogeneity, and band A and C were identified to be α- and β-amylase, respectively. Some of their enzymic properties have been studied.
TL;DR: Growth, and protease and amylase activities were inhibited in Spodoptera littoralis Boisduval larvae fed on the cotyledons of a high gossypol cotton strain, resulting in an increased inhibition of proteolysis with rising gOSSypol concentration.
Abstract: Growth, and protease and amylase activities were inhibited in Spodoptera littoralis Boisduval larvae fed on the cotyledons of a high gossypol cotton strain. Gossypol interacts rapidly in vitro with protease or its proteinaceous substrate, resulting in an increased inhibition of proteolysis with rising gossypol concentration.
TL;DR: Analysis of patient sera by RIA shows that salivary amylase constitutes approximately 60% of the total serum amylases, that the salivaries found in the serum of patients with Sjogren's syndrome and macroamylasemia is immunologically indistinguishable from that of normal persons.
TL;DR: An ovarian carcinoma producingAmylase isoenzyme electrophoresis is of value in differentiating pancreatic from nonpancreatic sources of increased amylase.
TL;DR: The α-amylase secreted by the aleurone layer of whole barley grains were relatively rich in histidine and relatively poor in glutamate/glutamine and serine when compared to other eukaryotic proteins as discussed by the authors.
TL;DR: It is postulate that the generalized hyperamylasemia may be due to reduced extrarenal catabolism of amylase, a previously undescribed phenomenon.
Abstract: Seventeen patients with chronic hyperamylasemia were studied using standard clinical and laboratory parameters, amylase/creatinine clearance ratios, and polyacrylamide gel electrophoresis of serum amylases. These patients, none of whom had evidence of pancreatic disease or other specific source for the elevated serum amylase, fell into three groups: (1) Normal serum isoamylase profile and normal amylase clearance (6 patients). We postulate that the generalized hyperamylasemia may be due to reduced extrarenal catabolism of amylase, a previously undescribed phenomenon. (2) Macroamylasemia and very low amylase clearance (9 patients). Seven of the nine patients had recurrent epigastric pain. Evidence for an autoimmune basis is discussed. (3) Salivary-type hyperamylasemia and low amylase clearance (2 patients). This entity may really be macroamylasemia in which the macroamylase complex dissociated during analysis. Chronic hyperamylasemia is often not of pancreatic origin. The assumption that the pancreas is at fault, especially if there is abdominal pain, may cause morbidity due to gross overtreatment.
TL;DR: The rat parotid provides an excellent model for the further investigation of the mechanisms of these diverse effects of amylase biosynthesis and release and stimulation of alpha-receptors can inhibit biosynthesis without inhibiting release.
Abstract: 1. Amylase biosynthesis and release in the rat parotid were studied under various conditions. Incorporation of [(3)H]leucine into amylase, extracted from the tissue by immunoadsorbent, was measured and found to be time-dependent and totally inhibited by the protein synthesis inhibitor puromycin. 2. Adrenaline, at a concentration (10mum) that gave maximum stimulation of release, inhibited [(3)H]leucine incorporation into both total protein and amylase. This effect was reversed by phentolamine. 3. Adrenaline (1mum) and isoproterenol (10mum) stimulated biosynthesis of total protein and amylase. These effects were blocked by propranolol, as were the effects on release. Dibutyryl cyclic AMP (2mm) mimicked the effects of isoproterenol and adrenaline (1mum) on both amylase biosynthesis and release. All the above stimulatory effects on amylase biosynthesis were only observed if the tissue was pretreated with effector before pulse-labelling with [(3)H]leucine. 4. Insulin (625muunits/ml initial concentration, 150muunits/ml final concentration) stimulated incorporation of [(3)H]leucine into total protein and amylase when added to the tissue at the same time as the leucine. 5. Carbamoylcholine (10mum) decreased [(3)H]leucine incorporation into total protein and amylase when both were added to the tissue simultaneously, but this effect was prevented by removal of effector and washing the tissue before addition of [(3)H]leucine. 6. Stimulation of beta-adrenergic receptors increased both amylase release and biosynthesis, but stimulation of alpha-receptors can inhibit biosynthesis without inhibiting release. Cholinergic agents can also inhibit amylase biosynthesis, but stimulate release. Insulin at approximately physiological concentration can increase incorporation of leucine into amylase without stimulating release. The system described therefore provides an excellent model for the further investigation of the mechanisms of these diverse effects.
TL;DR: The hypothesis that this difference in amylase activity will cause a selective advantage when the two strains compete for food and starch is a limiting factor is supported.
Abstract: Properties of amylase of two strains homozygous for two different amylase variants of Drosophila rnelanogaster were determined. Amylase of larvae and adults of both strains showed a pH optimum around pit 7.0. The Amy I enz)alae showed a higher temperature stability. They differed in maximal activity (for Amy 1 Vma x = 26.2 mU/9, for Amy4, 6 Vma x = 128.9 mU/ 9) and Michaelis constants (for Amy 1 K m = 0.09% starch, for Amy a,6 K m = 0.25% starch). This means that the activity difference measured at saturating substrate concentrations will not vanish or will not be reversed at lower substrate concentrations. This supports the hypothesis that this difference in amylase activity will cause a selective advantage when the two strains compete for food and starch is a limiting factor.
TL;DR: In this paper, mixed cultures of Endomycopsis fibuligera and Candida utilis on waste material obtained from a potato processing plant were only partially successful; poor amylase production by Endomycomopsis resulted in slow growth of the Candida.
Abstract: Attempts to grow mixed cultures of Endomycopsis fibuligera and Candida utilis on waste material obtained from a potato processing plant were only partially successful; poor amylase production by Endomycopsis resulted in slow growth of the Candida. There was extensive conversion of starch to glucose when waste, which had been treated with a high speed shear/disintegrator, was hydrolyzed by industrial amylases derived from Aspergillus niger and Bacillus licheniformis. Growth of C. utilis on the separated liquid phase of the hydrolysate, supplemented with inorganic nitrogen, proceeded normally; the yields and growth rates were similar to those obtained with conventional substrates.