Effects of high dietary inclusion of Arthrospira platensis, either extruded or supplemented with a super-dosing multi-enzyme mixture, on broiler growth performance and major meat quality parameters.

BACKGROUND: This investigation assessed the effects of high dietary inclusion of Spirulina (Arthrospira platensis) on broiler chicken growth performance, meat quality and nutritional attributes. For this, 120 male broiler chicks were housed in 40 battery brooders (three birds per brooder). Initially, for 14 days, a standard corn and soybean meal diet was administered. Subsequently, from days 14 to 35, chicks were assigned to one of the four dietary treatments (n = 10 per treatment): (1) control diet (CTR); (2) diet with 15% Spirulina (SP); (3) diet with 15% extruded Spirulina (SPE); and (4) diet with 15% Spirulina plus a super-dosing enzymes supplement (0.20% pancreatin extract and 0.01% lysozyme) (SPM). RESULTS: Throughout the experimental period, both SP and SPM diets resulted in decreased final body weight and body weight gain compared to control (p < 0.001), with the SPE diet showing comparable results to CTR. The SPE diet prompted an increase in average daily feed intake (p = 0.026). However, all microalga treatments increased the feed conversion ratio compared to CTR. Dietary inclusion of Spirulina notably increased intestinal content viscosity (p < 0.010), which was mitigated by the SPM diet. Spirulina supplementation led to lower pH levels in breast meat 24 h post-mortem and heightened the b* colour value in both breast and thigh meats (p < 0.010). Furthermore, Spirulina contributed to an increased accumulation of total carotenoids, n-3 polyunsaturated fatty acids (PUFA), and saturated fatty acids (SFA), while diminishing n-6 PUFA, thus altering the n-6/n-3 and PUFA/SFA ratios favourably (p < 0.001). However, it also reduced zinc concentration in breast meat (p < 0.001). CONCLUSIONS: The findings indicate that high Spirulina levels in broiler diets impair growth due to increased intestinal viscosity, and that extrusion pre-treatment mitigates this effect. Despite reducing digesta viscosity, a super-dosing enzyme mix did not improve growth. Data also indicates that Spirulina enriches meat with antioxidants and n-3 PUFA but reduces α-tocopherol and increases saturated fats. Reduced zinc content in meat suggests the need for Spirulina biofortification to maintain its nutritional value.

Advances in immobilization of phytases and their application.

The review describes the advances in the phytase immobilization for the past decade and their biotechnological applications. Different approaches for phytase immobilization are described including the process using organic and inorganic matrices and microbial cells, as well as nanostructures of various nature. Moreover, the immobilization of phytase-producing microbial cells and the use of cross-linked phytase aggregates have been under consideration. A detailed classification of various carriers for immobilization of phytases and the possibility of their applications are presented. A particular attention is drawn to a breakthrough approach of biotechnological significance to the design of microencapsulation of bacterial phytase from Obesumbacterium proteus in the recombinant extremophile of Yarrowia lipolytica.

Effects of diet hulless barley and beta-glucanase levels on ileal digesta soluble beta-glucan molecular weight and carbohydrate fermentation in laying hens.

Exogenous ß-glucanase (BGase) improves nutrient digestibility and production performance in laying hens fed barley-based diets, but the effect of enzyme and the dosage on ß-glucan depolymerization and fermentation in the gastrointestinal tract is poorly understood. The objectives of the study were to determine the effects of hulless barley (HB) and BGase levels on digestive tract ß-glucan depolymerization and fermentation in laying hens. A total of 108 Lohman-LSL Lite hens were housed in cages and fed 2 levels of HB (CDC Fibar; 0 and 73%) by substituting wheat in the diet and graded levels of BGase (Econase GT 200 P from ABVista; 0, 0.01 and 0.1% - 0, 20,000, and 200,000 BU/kg) in a 2 × 3 factorial arrangement. Birds were fed experimental diets for 8 weeks, starting at 35 wk of age. Digestive tract samples were collected at the end of the experiment. Statistical significance was set at P ≤ 0.05. Beta-glucan peak molecular weight was lower with the 0.1 compared to both 0 and 0.01% BGase levels, whereas weight average molecular weight was lower with the 0.1 compared to 0% BGase for 73% HB. The maximum molecular weight for the smallest 10% ß-glucan molecules decreased with the increasing BGase. Overall, ß-glucan molecular weight in the ileum was higher when the birds were given 73 in comparison to 0% HB diets. Total and major short chain fatty acids (SCFA) in the ileum were lower with 0.1 and 0.01 (except propionic acid) compared to 0% BGase in the birds fed 73% HB, but not 0% HB. Interactions between the main effects were found for the cecal acetic and isobutyric acids. In conclusion, exogenous BGase depolymerized high molecular weight ß-glucan in HB and wheat. The effects of HB and BGase on carbohydrate fermentation were not apparent, although it appears ileal SCFA concentrations were lower with increasing levels of BGase.

Feed endoxylanase type and dose affect arabinoxylan hydrolysis and fermentation in ageing broilers.

Despite the general use of endoxylanases in poultry feed to improve broiler performance, the abundance of different endoxylanase products and the variable response to their application in the field prevent a clear understanding of endoxylanase functionality in vivo. To gain insight into this functionality, we investigated the impact of endoxylanase type (Belfeed from Bacillus subtilis versus Econase XT from Nonomuraea flexuosa) and dose (10, 100, 1,000 mg/kg) in combination with broiler age on arabinoxylan (AX) hydrolysis and fermentation in broilers (Ross 308) fed a wheat-soy based diet. In a digestibility trial and a performance trial, a total of 1,057 one-day-old chicks received the control diet or 1 of the 6 endoxylanase supplemented wheat-soy based diets with, respectively, 5 replicate cages and 8 replicate pens per dietary treatment per trial. The AX content and structure, the AX digestibility values and the short-chain fatty acids produced were analysed at the level of the ileum, caeca and excreta at d 11 and 36. Endoxylanase supplementation resulted in a more extensive solubilisation of wheat AX and a reduction in the intestinal viscosity compared to the control (P < 0.05). A high endoxylanase dose was, however, required to obtain increased hydrolysis of the dietary AX along the gastrointestinal tract against the control (P < 0.001). Depending on the type of endoxylanase, a pool of AX with distinct physicochemical properties was created. The B. subtilis endoxylanase created a large pool of soluble AX in the ileum, thereby increasing ileal viscosity compared to broilers fed an endoxylanase from N. flexuosa (P < 0.001). The N. flexuosa endoxylanase mainly triggered caecal AX fermentation in young broilers, by delivering easily fermentable AX substrates with a low degree of polymerisation (P = 0.03). The effects were particularly present in young broilers (d 11). From this study, it is clear that the type and dose of endoxylanase added to wheat-soy based diets determine the nature of AX substrates formed. These, in turn, affect the intestinal viscosity and the interplay between the dietary AX compounds and microbiota, hence dictating AX digestion at young broiler ages and performance outcomes towards slaughter age.

Hulless barley and ß-glucanase affect ileal digesta soluble beta-glucan molecular weight and digestive tract characteristics of coccidiosis-vaccinated broilers.

Exogenous ß-glucanase (BGase) in barley-based feed has been shown to reduce digesta viscosity in chickens, and thereby improve performance. Less well studied is the potential for BGase to convert barley ß-glucan into low molecular weight carbohydrates, which might influence digestive tract function and enteric disease. Coccidiosis-vaccinated broiler chickens were fed graded levels of hulless barley (HB) and BGase to determine their effects on ß-glucan depolymerization and digestive tract characteristics. Broilers were fed high ß-glucan HB (0%, 30% and 60% replacing wheat) and BGase (0%, 0.01% and 0.1%) in a 3 × 3 factorial arrangement. A total of 5,346 broilers were raised in litter floor pens and vaccinated for coccidiosis on d 5. Each treatment was assigned to 1 pen in each of 9 rooms. The significance level was set at P ≤ 0.05. At both 11 and 33 d of broiler ages, peak molecular weight of ß-glucan in ileal digesta decreased with increasing BGase for 30% and 60% HB. The maximum molecular weight for the smallest 10% ß-glucan molecules (MW-10%) decreased with BGase at both ages for 30% and 60% HB; for birds fed 0% HB, only 0.1% BGase decreased MW-10%. The 0.1% BGase increased caecal short chain fatty acids (SCFA) compared to the 0.01% BGase at d 11 only for the 60% HB. Ileal pH increased with increasing HB and BGase at d 11 and 33. Caecal pH was lower for 0.1% BGase than 0% BGase for 60% HB at d 11. Relative mRNA expression of interleukin 6 (IL-6) and IL-8 in the ileum increased with 0.1% BGase at d 11 and 33, respectively, whereas expression of ileal mucin 2 (MUC2) decreased with 0.1% BGase at d 33. In the caeca, interactions between HB and BGase were significant for monocarboxylate transporter 1 (MCT1) and mucin 5AC (MUC5 AC) on d 11, but no treatment effects were found at d 33. In conclusion, BGase depolymerized high molecular weight ß-glucan in HB in a dose-dependent manner. Hulless barley and BGase did not increase SCFA concentrations (except for 60% HB with 0.1% BGase at d 11) and caused minor effects on digestive tract histomorphological measurements and relative mRNA gene expression.

The influence of xylanase on the fermentability, digestibility, and physicochemical properties of insoluble corn-based fiber along the gastrointestinal tract of growing pigs.

In theory, supplementing xylanase in corn-based swine diets should improve nutrient and energy digestibility and fiber fermentability, but its efficacy is inconsistent. The experimental objective was to investigate the impact of xylanase on energy and nutrient digestibility, digesta viscosity, and fermentation when pigs are fed a diet high in insoluble fiber (>20% neutral detergent fiber; NDF) and given a 46-d dietary adaptation period. A total of 3 replicates of 20 growing gilts were blocked by initial body weight, individually housed, and assigned to 1 of 4 dietary treatments: a low-fiber control (LF) with 7.5% NDF, a 30% corn bran high-fiber control (HF; 21.9% NDF), HF + 100 mg xylanase/kg (HF + XY [Econase XT 25P; AB Vista, Marlborough, UK]) providing 16,000 birch xylan units/kg; and HF + 50 mg arabinoxylan-oligosaccharide (AXOS) product/kg (HF + AX [XOS 35A; Shandong Longlive Biotechnology, Shandong, China]) providing AXOS with 3-7 degrees of polymerization. Gilts were allowed ad libitum access to fed for 36-d. On d 36, pigs were housed in metabolism crates for a 10-d period, limit fed, and feces were collected. On d 46, pigs were euthanized and ileal, cecal, and colonic digesta were collected. Data were analyzed as a linear mixed model with block and replication as random effects, and treatment as a fixed effect. Compared with LF, HF reduced the apparent ileal digestibility (AID), apparent cecal digestibility (ACED), apparent colonic digestibility (ACOD), and apparent total tract digestibility (ATTD) of dry matter (DM), gross energy (GE), crude protein (CP), acid detergent fiber (ADF), NDF, and hemicellulose (P < 0.01). Relative to HF, HF + XY improved the AID of GE, CP, and NDF (P < 0.05), and improved the ACED, ACOD, and ATTD of DM, GE, CP, NDF, ADF, and hemicellulose (P < 0.05). Among treatments, pigs fed HF had increased hindgut DM disappearance (P = 0.031). Relative to HF, HF + XY improved cecal disappearance of DM (162 vs. 98 g; P = 0.008) and NDF (44 vs. 13 g; P < 0.01). Pigs fed xylanase had a greater proportion of acetate in cecal digesta and butyrate in colonic digesta among treatments (P < 0.05). Compared with LF, HF increased ileal, cecal, and colonic viscosity, but HF + XY decreased ileal viscosity compared with HF (P < 0.001). In conclusion, increased insoluble corn-based fiber decreases digestibility, reduces cecal fermentation, and increases digesta viscosity, but supplementing xylanase partially mitigated that effect.

Effects of hulless barley and exogenous beta-glucanase levels on ileal digesta soluble beta-glucan molecular weight, digestive tract characteristics, and performance of broiler chickens.

The reduced use of antibiotics in poultry feed has led to the investigation of alternatives to antibiotics, and one such substitution is fermentable carbohydrates. Exogenous ß-glucanase (BGase) is commonly used in poultry fed barley-based diets to reduce digesta viscosity. The effects of hulless barley (HB) and BGase levels on ileal digesta soluble ß-glucan molecular weight, digestive tract characteristics, and performance of broiler chickens were determined. A total of 360 day-old broilers were housed in battery cages (4 birds per cage) and fed graded levels of high ß-glucan HB (CDC Fibar; 0, 30, and 60% replacing wheat) and BGase (Econase GT 200 P; 0, 0.01, and 0.1%) in a 3 × 3 factorial arrangement. Beta-glucan peak molecular weight in the ileal digesta was lower with 30 and 60 than 0% HB, whereas the peak decreased with increasing BGase. The weight average molecular weight was lower at 0.1 than 0% BGase in wheat diets, whereas in HB diets, it was lower at 0.01 and 0.1 than 0% BGase. The maximum molecular weight was lower with 0.01 and 0.1 than 0% BGase regardless of the HB level. The maximum molecular weight was lower with HB than wheat at 0 or 0.01% BGase. Overall, empty weights and lengths of digestive tract sections increased with increasing HB, but there was no BGase effect. Hulless barley decreased the duodenum and jejunum contents, whereas increasing the gizzard (diets with BGase), ileum, and colon contents. The jejunum and small intestine contents decreased with increasing BGase. Ileal and colon pH increased with increasing HB, but there was no BGase effect. Treatment effects were minor on short-chain fatty acids levels and performance. In conclusion, exogenous BGase depolymerized the ileal digesta soluble ß-glucan in broiler chickens in a dose-dependent manner. Overall, feed efficiency was impaired by increasing HB levels. However, HB and BGase did not affect carbohydrate fermentation in the ileum and ceca, although BGase decreased ileal viscosity and improved feed efficiency at the 0.1% dietary level.

Hulless barley and beta-glucanase levels in the diet affect the performance of coccidiosis-challenged broiler chickens in an age-dependent manner.

Diet ß-glucanase (BGase) depolymerizes viscous ß-glucan into lower molecular weight carbohydrates, which might act as a prebiotic in chickens exposed to enteric disease. Coccidiosis-challenged broiler chickens were fed graded levels of hulless barley (HB) and BGase to determine their effects on growth performance. Broilers were fed high ß-glucan HB (CDC Fibar; 0, 30, and 60% replacing wheat) and BGase (Econase GT 200P; 0, 0.01, and 0.1%) in a 3 × 3 factorial arrangement. A total of 5,346 broilers were raised in litter floor pens and vaccinated for coccidiosis in feed and water on day 5. Each treatment was assigned to 1 pen (66 birds) in each of 9 rooms. Statistical significance was set at P ≤ 0.05. Overall, HB decreased body weight gain (BWG) and increased feed: gain ratio (F:G) of broilers. From day 0 to 11, BGase did not affect BWG and F:G, at the 0 and 30% HB. However, at 60% HB, the 0.01% BGase improved them, and the 0.1% BGase had no effect on BWG and increased F:G. For the day 22 to 32 and 0 to 32 periods, BGase did not affect BWG for 0 and 30% HB levels, but for the 60% HB, both BGase levels increased gain. The 0.1% level of BGase resulted in the lowest F:G for all HB levels, with the degree of response increasing with HB. No interaction was found for ileal digesta viscosity at day 11; the level of HB did not affect viscosity, but both levels of BGase decreased viscosity. At day 33, BGase did not affect viscosity at 0 and 30% HB levels, but viscosity was lowered for the 0.1% BGase treatment at the 60% HB level. In conclusion, HB reduced broiler performance, and BGase alleviated most but not all the effects. In young birds fed 60% HB, 0.1% BGase did not impact BWG and increased F:G.

Taguchi optimization and scale up of xylanase from Bacillus licheniformis isolated from hot water geyser.

BACKGROUND: Xylanase is one of the widely applied industrial enzymes with diverse applications. Thermostability and alkali tolerance are the two most desirable qualities for industrial applications of xylanase. In this paper, we reveal the statistical Taguchi optimization strategy for maximization of xylanase production. The important process parameters pH, temperature, concentration of wheat bran, and concentration of yeast extract were optimized using the Taguchi L8 orthogonal array where the 4 factors were considered at 2 levels (high and low). RESULTS: The optimized conditions given by model were obtained as follows: (i) pH 6, (ii) culture temperature 35 °C, (iii) concentration of xylan 2% w/v, (iv) concentration of wheat bran 2.5% w/v. The production was scaled upto 2.5 L bioreactor using optimized process parameters. A high xylanase titer of 400 U/ml could be achieved in less than 60 h of culture in the reactor. CONCLUSION: Optimization was successful in achieving about threefold increase in the yield of xylanase. The optimized conditions resulted in a successful scale up and enhancement of xylanase production.

Isolation of four xylanases capable of hydrolyzing corn fiber xylan from Paenibacillus sp. H2C.

Corn fibre xylan (CX) shows high resistance to enzymatic hydrolysis due to its densely decorated side chains. To find enzymes capable of hydrolyzing CX, we isolated a bacterial strain (named H2C) from soil, by enrichment culture using non-starch polysaccharides of corn as the sole carbon source. Analysis based on the 16S rRNA sequence placed strain H2C within genus Paenibacillus. Enzymes were purified from supernatant of culture broth of strain H2C based on solubilizing activities toward CX. Four enzymes, Xyn5A, Xyn10B, Xyn11A, and Xyn30A, were successfully identified, which belong to glycoside hydrolase (GH) families, 5, 10, 11, and 30, respectively. Phylogenetic analysis classified Xyn5A in subfamily 35 of GH family 5, a subfamily of unknown function. Their activities toward beechwood xylan and/or wheat arabinoxylan indicated that these enzymes are ß-1,4-xylanases. They showed high solubilizing activities toward a feed material, corn dried distiller's grains with solubles, compared to five previously characterized xylanases.Abbreviations : CX: corn fibre xylan; DDGS: corn dried distiller's grains with solubles.

Variation in levels of non-starch polysaccharides and endogenous endo-1,4-ß-xylanases affects the nutritive value of wheat for poultry.

1. Endo-1,4-ß-xylanase is known to improve the nutritive value of wheat-based diets for poultry by degrading dietary arabinoxylans. However, broilers' response to supplementation of wheat-based diets with exogenous endo-1,4-ß-xylanase is not always observed. 2. In this study, 108 different wheat lots were analysed for levels of extract viscosity as well as for endogenous endo-1,4-ß-xylanase activity, and the impact of these two variables in animal performance was tested. 3. Results revealed that endogenous endo-1,4-ß-xylanase activity and extract viscosity content varied widely among different wheat lots. Thus, a trial was conducted to evaluate the efficacy of exogenous enzyme supplementation in broiler diets using wheats with different levels of extract viscosity and endogenous endo-1,4-ß-xylanase activity. 4. The data revealed that exogenous enzyme supplementation was only effective when the wheat present in the diet had high levels of extract viscosity (14.8 cP) with low endogenous endo-1,4-ß-xylanase activity (347.0 U/kg). Nevertheless, it is apparent that exogenous microbial xylanases reduce digesta extract viscosity and feed conversion ratio independently of the endogenous properties presented by different wheat lots. 5. The data suggest that extract viscosity and/or endogenous endo-1,4-ß-xylanase activity affect the response to enzyme supplementation by poultry fed on wheat-based diets.

Ergot Alkaloids in Fattening Chickens (Broilers): Toxic Effects and Carry over Depending on Dietary Fat Proportion and Supplementation with Non-Starch-Polysaccharide (NSP) Hydrolyzing Enzymes.

Ergot alkaloids (EA) are mycotoxins produced by Claviceps purpurea. EA-toxicity is poorly characterized for fattening chickens. Therefore, a dose-response study was performed to identify the lowest, and no observed adverse effect levels (LOAEL and NOAEL, respectively) based on several endpoints. Non-starch-polysaccharide (NSP) cleaving enzyme addition and dietary fat content were additionally considered as factors potentially influencing EA-toxicity. Feed intake was proven to respond most sensitively to the EA presence in the diets. This sensitivity appeared to be time-dependent. While LOAEL corresponded to a total dietary EA content of 5.7 mg/kg until Day 14 of age, it decreased to 2.03 mg/kg when birds were exposed for a period of 35 days. Consequently, NOAEL corresponded to an EA content of 2.49 mg/kg diet until Day 14 of age, while 1.94 mg/kg diet applied until Day 35 of age. Liver lesions indicating enzyme activities in serum were increased after 14 days of exposure. Dietary fat content and NSP-enzyme supplementation modified EA toxicity in an interactive manner. The EA residues in serum, bile, liver and breast meat were <5 ng/g suggesting a negligible carry over of intact EA.

Purification and partial characterization of an acidic α-amylase from a newly isolated Bacillus subtilis ZJ-1 that may be applied to feed enzyme.

An amylase-producing strain was isolated from soy sauce and designated as Bacillus subtilis ZJ-1. Purification of α-amylase from B. subtilis ZJ-1 to homogeneity by ethanol fractionation, ultrafiltration, and Sephadex G-100 gel filtration resulted in recovery of 8.9% and a specific activity of 542.7 U/mg protein. The molecular mass was estimated to be 58 kD by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme reached its maximum activity at a pH of 5.0 and a temperature of 50°C. The enzyme remained at 89.4 ± 3.0% of its activity at 40°C. The enzyme retained 87.7 ± 3.7% and 63.4 ± 2.9% of its original activity at 40°C after a 60-min incubation in the presence of 5 mM CaCl2 at a pH of 5.0 and 4.0, respectively. These properties indicate that the novel enzyme has a theoretically high survival rate and excellent starch catalytic efficiency in the typical chicken gastrointestinal-tract environment (pH 3.5-7.0, 40°C). In addition, the enzyme remained at 78.4 ± 3.6% of its activity after a 5-min incubation at 80°C, which demonstrates that the enzyme could maintain a high survival rate in the pelleting process of feed production. The characteristics just described make this enzyme a good candidate for use as a chicken feed enzyme.

Use of Bacillus subtilis isolates from Tua-nao towards nutritional improvement of soya bean hull for monogastric feed application.

UNLABELLED: Soya bean hull (SBH) is a cheap and high-fibre content feed ingredient that obtained after soya bean oil extraction. Microbial fermentation was expected to improve SBH qualities before applying to animals, especially monogastric animals. Two bacterial strains, Bacillus subtilis MR10 and TK8 that were isolated from Tua-nao, a traditional fermented soya bean in northern Thailand, were used for fermented soya bean hull (FSBH) production. Both could easily grow at 37°C in SBH as the sole substrate. MR10 produced the highest ß-mannanase activity (400 U g(-1) SBH) on day 2, while TK8 produced the highest cellulase activity (14·5 U g(-1) SBH) on day 3. After fermentation, the nutritional quality of SBH was obviously improved by an increase in soluble sugars, soluble proteins, crude protein and crude lipid, and a decrease in the content of raffinose family oligosaccharides. Scavenging activity (%) of SBH against ABTS radical cation was also increased from 14 to 27 and 20% by MR10 and TK8 fermentation, respectively. According to the GRAS property of these both strains and various improvements of nutritional values, the fermented SBH proved to be a potential feed ingredient, especially for the monogastric animals. SIGNIFICANCE AND IMPACT OF THE STUDY: Normally, soya bean hull has been recognized as only a worthless by-product from soya bean oil production process because of its low utilizable nutrients. Our study introduced an alternative way to utilize this worthless residue using biotechnological knowledge. The nutritional quality of soya bean hull was improved by microbial fermentation. Fermented soya bean hull can be used as a cheap, safe and high-nutrient feed ingredient for livestock production, especially monogastric animals, to promote their growth performances, instead of using antibiotics in some regions of the world.

ß-Mannanase production by Aspergillus niger BCC4525 and its efficacy on broiler performance.

BACKGROUND: Mannan is a hemicellulose constituent commonly found in plant-derived feed ingredients. The gum-like property of mannan can obstruct digestive enzymes and bile acids, resulting in impaired nutrient utilisation. In this study, ß-mannanase production by Aspergillus niger strain BCC4525 was investigated using several agricultural residues under solid state condition. The biochemical properties of the target enzyme and the effects of enzyme supplementation on broiler performance and energy utilisation were assessed. RESULTS: Among five carbon sources tested, copra meal was found to be the best carbon source for ß-mannanase production with the maximum yield of 1837.5 U g(-1) . The crude ß-mannanase exhibited maximum activity at 80 °C within a broad range of pH from 2 to 6. In vitro digestibility assay, which simulates the gastrointestinal tract system of broilers, showed that ß-mannanase could liberate reducing sugars from corn/soybean diet. Surprisingly, ß-mannanase supplementation had no significant effect on broiler feed intake, feed conversion rate or energy utilisation. CONCLUSION: A high level of ß-mannanase was produced by A. niger BCC4525 under solid state condition using copra meal as carbon source. Although the enzyme has the desired properties of an enzyme additive for improving broiler performance, it does not appear to be beneficial.

Producción de enzima fitasa de aspergillus ficuum con residuos agroindustriales en fermentación sumergida y sobre sustrato sólido / Phytase production by aspergillus ficuum in submergida y sobre sustrato solido

Se describe la producción de fitasa mediante cultivos del tipo sumergido (SmF) y sobre sustrato sólido (SSF) con Aspergillus ficuum DSM 932 en medios de cultivos basados en residuos de la agroindustria. La actividad enzimática fitásica se usó como medida indirecta de la producción de la enzima. En SmF, pH 5,3 y 25 ºC, se trabajó en fermentadores de diferentes volúmenes y con el mayor se operó con diferentes niveles de aireación y agitación. En SSF a 25 ºC se usaron placas de Petri. En SmF con un medio basado en cereales se presentó la mejor actividad neta (0,25 FTU/mL) al sexto día para 300 rpm y 0,5 vvm. En SSF, la torta de canola resultó ser el mejor sustrato con una actividad fitásica neta máxima al tercer día de 6,79 FTU/mL de extracto, equivalente a 33,96 FTU/g de sustrato sólido o 56,43 FTU/g de sustrato seco. Aplicando tecnologías de membrana se concentró un extracto de fitasa a partir de una SmF en medio basado en cereales y también fue posible purificar 6,33 veces un extracto de fitasa producido en SSF con torta de canola, diafiltrando tres veces consecutivas el retenido de 100 kDa. La enzima fitasa de la cepa A. ficuum DSM 932 mostró tener un tamaño ≥ 100 kDa.

Phytase production by submerged fermentation (SmF) and solid state fermentation (SSF) using Aspergillus ficuum DSM 932 in agro-waste-based culture media is described here. Phytase enzyme activity was used for the indirect measurement of enzyme production. Fermentation was carried out in SmF, pH 5.3 at 25 ºC with two fermenters having different volumes; the largest one had different levels of aeration and agitation. Petri dishes were used for SSF at 25 °C. A cereal-based medium obtained the best net activity (0.25 FTU mL-1) for SmF on the sixth day at 300 rpm at 0.5 vvm. Canola cake was the best substrate for SSF, having maximum net phytase activity on the third day: 6.79 FTU mL-1 extract, equivalent to 33.96 FTU g-1 solid substrate or 56.43 FTU g-1 dry substrate. A phytase extract was concentrated from an SmF-based medium in cereals by applying membrane technologies. A phytase extract produced in SSF with canola cakes was purified 6.33 times using three consecutive diafiltrations of the 100 kDa retentate. A. ficuum DSM 932 phytase was ≥ 100 kDa in size.