中药渣固态发酵生产蛋白饲料

利用白腐菌对中药渣进行固态发酵。研究了葡萄糖添加量、（NH4）2SO4添加量、初始pH值、料水质量比、发酵时间对发酵的影响,初步确定了中药渣固态发酵的最优工艺条件。结果表明,中药渣在经过白腐菌3-5d静止发酵后,发酵产物的真蛋白质量分数可达19.05%,比原料本身的真蛋白质量分数高71.34%,粗纤维质量分数由29.14%降低到17.42%。由此可见,该方法可使中药渣得到合理的利用,其发酵产物可作为蛋白饲料资源。     

三七渣固态发酵生产蛋白饲料

以三七渣为原料,利用康宁木霉固态发酵生产蛋白饲料,考察了培养条件对康宁木霉固态发酵三七渣的影响,采用正交试验优化了发酵条件.研究结果表明,最佳发酵条件为氮源添加量为40mg硫酸铵/g干药渣、固液比1.0:1.5、发酵时间5d、原料粒径80目,在上述发酵条件下,三七渣中真蛋白含量由9.97%提高至19.40%,粗纤维含量从27.45%降低至11.91%.     

樟芝菌固态发酵生产三萜类化合物

通过单因素实验,考察了固态发酵基质、外加氮源、初始含水量、装料量,接种量及培养温度对樟芝菌(Antrodia cinnamomea)固态发酵生产三萜系化合物的影响。单因素实验结果显示,NH4Cl加量、初始含水量、装料量和接种量对樟芝三萜系化合物含量的影响较显著,以上述显著因素作为随机因子,进行均匀设计实验,采用逐步回归方法对实验结果进行分析。实验结果表明:以小米为固态发酵基质,添加NH4Cl0.2%,初始含水量65%(g水/g干基),1L三角瓶装料量为120g,接种量55%(v/w),培养温度为28℃的条件下,樟芝三萜系化合物含量达到87.62mg/g(干基),比未优化前提高1.56倍;固态发酵产物中三萜系化合物的含量是樟芝液态发酵产物中的5倍。     

固态发酵的红芪药渣生产蛋白饲料的可行性研究

蛋白饲料短缺是严重的世界问题,新型蛋白饲料资源开发刻不容缓,中药渣的处理问题势在必行;甘肃省地道药材红芪食药两用,药理活性成分丰富,临床应用广泛。固态发酵技术渐趋成熟,中药渣固态发酵制备蛋白饲料应用广泛且效果良好。红芪药渣排放量较大,营养和药用价值较高,将其资源化利用,固态发酵制备蛋白饲料等,既节约又环保,更有经济效益,有利于本地畜牧、养殖业的发展。以大量学术文献为支撑,课题组优选红芪药渣进行固态发酵生产蛋白饲料,具有可行性,开发利用前景光明广阔。     

红曲霉固态发酵中桔霉素的抑制研究

通过发酵条件优化和添加外源物质,建立有效抑制桔霉素产生的红曲米固态发酵工艺。首先对红曲霉Winter4固态发酵的3个发酵条件(接菌量、发酵温度及装料量)进行了单因素实验,进一步通过正交实验确定红曲霉Winter4低产桔霉素的最佳发酵条件为:发酵温度32℃、装料量35 g、接菌量14%。同时,选择乳酸钠、环磷酸腺苷和生物素,研究了外源添加物对红曲霉Winter4产桔霉素的影响。结果显示,添加乳酸钠对桔霉素没有明显的抑制作用,而低浓度的乳酸钠反而增加桔霉素的生成量,添加0.36 g/kg的环磷酸腺苷和30μg/kg的生物素对桔霉素的抑制率分别可达到96%和75%。     

混种固态发酵酱醋渣生产赖氨酸强化的蛋白饲料研究

考察了酵母菌和赖氨酸菌混种固态发酵酱醋渣原料的方法对饲料蛋白质量的影响。研究结果表明，这是制备优质蛋白饲料的有效途径，饲料蛋白质量高，发酵产物酵母数达129．02亿个/g(干基），粗蛋白44．36％，真蛋白34．60％，氨基酸总量30．01％，必需氨基酸配比平衡好，赖氨酸的比例高达4．37g/(100g蛋白），胱氨酸，缬氨酸、异亮氨酸、亮氨酸、酪氨酸、苯丙氨酸、赖氨酸和苏氨酸等必需氨基酸的比例也都高于FAO标准值。     

刺梨果渣发酵饲料蛋白的工艺研究

以刺梨果渣为原料发酵生产饲料蛋白。研究以发酵产物中蛋白含量为指标,通过混合菌种进行发酵,筛选出最佳菌种比例,并通过单因素试验和正交试验得到混合菌发酵的最佳工艺条件。结果显示,最佳菌种组合为白地霉/康宁木霉/热带假丝酵母（2∶1∶2）,产物中蛋白质含量为14.87%;混合菌发酵的最佳工艺条件为尿素添加量2%,装料量50 g/250 m L,料液比1∶1（g∶m L）,接种量17%,发酵温度30℃,发酵时间5 d。发酵产物中蛋白质含量较未发酵果渣提高了175.8%,游离氨基酸含量提高了56.3%,可溶性膳食纤维提高了37.34%,适口性得到改善,同时具有刺梨的特殊香味,适合作为饲料添加剂。     

微生物促生剂发酵玉米皮生产饲料蛋白研究

以玉米皮为基本碳源,通过单因素和正交试验,以产朊假丝酵母、啤酒酵母和白地霉联合固态发酵生产蛋白饲料进行了研究。以提高真蛋白含量为主要目的,优化得到最佳的发酵条件为菌液接种量7%,固态发酵培养基料水比1:1.8（g:mL）,发酵温度31 ℃,发酵时间80 h。在此条件下,真蛋白含量可达15.6%,是发酵前的1.94倍。     

响应面法优化蛹虫草菌固体发酵五味子药渣发酵条件

将五味子药渣用作蛹虫草菌发酵培养基且不添加其他任何营养物质,并以水料比、基质重量、接种量、发酵温度为考察因子,在单因素实验基础上,结合响应面法以发酵产物中虫草素含量为响应值对发酵条件进行优化。响应面法分析得出蛹虫草菌发酵五味子药渣最佳条件:水料比为2mL/g,基质重量为37g,接种量为23%,发酵温度为26℃。在此条件下发酵15d,发酵产物中虫草素含量高达5.1202mg/g;多糖含量为2.87%,相比发酵前五味子药渣中多糖含量提高了24.97%。结果说明,以五味子药渣作为蛹虫草菌发酵培养基,不仅可以提高五味子药渣的利用价值,而且可以降低发酵蛹虫草菌生产虫草素的成本。     

微生物转化麦芽根为蛋白饲料的研究

通过组合发酵确定黑曲霉、产朊假丝酵母、扣囊拟内孢霉为发酵麦芽根生产酸性蛋白酶蛋白饲料的最佳菌种组合,发酵培养基组成为麦芽根85%,麸皮15%,（NH4）2SO43%,pH5.5,含水量65%;发酵工艺为培养周期74h,两层纱布覆盖,30℃培养,接种量10%,发酵产物酸性蛋白酶活力达6489u/g(干基）,粗蛋白含量可达34.24%,比所用培养基粗蛋白含量提高36.3%,比原料本身粗蛋白含量提高50.3%,发酵产物粗纤维含量比原料下降32%。     

The thermostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: Investigation in vitro

This research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of their bioactive compounds, antioxidant activity and thermostability.It was found that polyphenols (mg GAE/g), flavanols (μg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots were 14.18 ± 0.7, 8.41 ± 0.5, 1.09 ± 0.06, 21.3 ± 1.2 and 7.29 ± 0.4, and of white onion - 11.11 ± 0.6, 6.78 ± 0.3, 0.71 ± 0.03, 17.00 ± 0.9 and 1.64 ± 0.08, respectively, and significantly higher in KLR (P < 0.05). The antioxidant activity of raw KLR water extract (139.4 ± 6.1, 53.1 ± 3.6 and 89.3 ± 4.6 μmol TE/g for DPPH, CUPRAC and ABTS, respectively) was significantly higher than in white onion (23.84 ± 1.8, 31.9 ± 2.1 and 38.14 ± 2.6 for DPPH, CUPRAC and ABTS, respectively, P < 0.05).The thermostability of the water KLR extract’s of polyphenols, flavanols, flavonoids, anthocyanins and tannins was high and even after 60 min of boiling remains as 40.0, 42.3, 50.5, 41.4 and 41.0%, respectively. After 60 min of boiling the most thermostable compounds were flavonoids - remaining at 50.5% in water extract of KLR. Also after 60 min of boiling the thermostability of the antioxidant activity of water extracts of KLR remained significantly high: 40.6, 42.3, 46.3 and 43.6%, according to DPPH, FRAP, ABTS and CUPRAC assays, respectively.Similar relationship was obtained with acetone extracts, but the value was lower than with the water ones. In conclusion, the contents of some bioactive compounds, the antioxidant activity and the thermostability in water and acetone extracts of KLR are significantly higher than the same indices in PWO. FTIR and fluorimetry can be used as additional markers for the characterization of bioactive compounds in vegetables.     

Quality assessment of wild European eel (Anguilla anguilla) stored in ice

The quality assessment of wild European eel (Anguilla anguilla) stored in ice and in boxes without ice (3 ± 1 °C) was investigated by the sensory analysis, levels of nucleotide breakdown products and biogenic amines for up to 19 days. Sensory analysis was assessed using the Tasmanian Food Research Unit Scheme. K and related values (K_i, G, P, H and F_r) were used as freshness indicators. Linear regressions (r²) obtained from K, K_i, G, P, H and F_r were 0.95, 0.96, 0.83, 0.96, 0.99 and 0.96, respectively, for eel stored in ice whereas, for eel kept in boxes without ice, the values were 0.86, 0.86, 0.96, 0.91, 0.98 and 0.86, respectively. When eel stored in ice and in boxes without ice were considered at the limit of acceptability by assessors at ∼12–14 days and ∼5–7 days, respectively, the average K, K_i and P values were ∼70–85%, H values were ∼60% and F_r values were ∼10% for both storage conditions. The level of histamine exceeded the legal limit (5 mg/100 g fish) in eel stored without ice after 6–7 days and, in ice, after 13–14 days of storage, at which time eels were rejected by the sensory panel. The concentrations of biogenic amines were higher in eel stored in boxes without ice than in eel kept in ice. The levels of histamine in the muscle of eel kept in boxes without ice and in ice increased to the maximum levels of 17.9 mg/100 g on day 12 and 12.6 mg/100 g on day 19, respectively.     

Protective effects of a synthetic soybean isoflavone against oxidative damage in chick skeletal muscle cells

The antioxidant and protective properties of a synthetic soybean isoflavone (SI) were investigated using chick skeletal (leg) muscle cells (SMC) isolated from 20-day-old Linnan yellow broiler chick embryo. Skeletal muscle cells were cultured in Dulbecco’s modified Eagle’s medium treated with 0, 12.5, 25, 50, 75 and 100 μM SI, respectively, under 80 μM H₂O₂/FeSO₄ conditions. After 24 h of incubation, SI reduced the loss of SMC under oxidative stress by H₂O₂/FeSO₄. The addition of SI significantly promoted SMC proliferation (P < 0.01). Upon treatment with 25, 50, 75 and 100 μM SI, the activity of total superoxide dismutase in the supernatant of the media was enhanced by 17.0%, 13.0%, 13.3% and 11.9%, respectively (P < 0.05). Compared to the control, the activity of glutathione peroxidase was significantly increased only at 25 μM concentration of SI (P < 0.05), and the increment was 90.7%. The activity of catalase was increased by 49.2% and 49.1%, respectively, at 75 and 100 μM SI (P < 0.01). The concentration of creatine kinase in the media was decreased by 61.6% and 60.6%, respectively, at 75 and 100 μM SI (P < 0.01). The addition of SI did not affect the activity of lactate dehydrogenase in the media. In conclusion, the SI protected skeletal muscle cells from oxidative damage, attributed to its antioxidant activity.     

Analysis of some selected catechins and caffeine in green tea by high performance liquid chromatography

Green tea seems to have a positive impact on health due to the catechins-found as flavanols. Thus, the present study was aimed to develop a low cost reversed phase high performance liquid chromatographic (HPLC) method for simultaneous determination of flavanol contents, namely catechin (C), epicatechin (EC), epigallocatechin (EGC), epicatechin 3-gallate (ECG) and epigallocatechin 3-gallate (EGCG) and caffeine in 29 commercial green tea samples available in a Saudi Arabian local market. A C-18 reversed-phase column, acetonitrile–trifluoroacetic acid as a mobile phase, coupled with UV detector at 205 nm, was successfully used for precise analysis of the tested analytes in boiled water of digested tea leaves. The average values of N (No. of theoretical plates), HETP (height equivalent of theoretical plates) and R_s (separation factor) (at 10 μg ml⁻¹ of the catechins EC, EGC, EGCG and ECG) were 2.6 × 10³ ± 1.2 × 10³, 1.7 × 10⁻³ ± 4.7 × 10⁻⁴ cm and 1.7 ± 5.53 × 10⁻², respectively. The developed HPLC method demonstrated excellent performance, with low limits of detection (LOD) and quantification (LOQ) of the tested catechins of 0.004–0.05 μg ml⁻¹ and 0.01–0.17 μg ml⁻¹, respectively, and recovery percentages of 96–101%. The influence of infusion time (5–30 min) and temperature on the content of the flavanols was investigated by HPLC. After a 5 min infusion of the tea leaves, the average concentrations of caffeine, catechin, EC, EGC, ECG and EGCG were found to be in the ranges 0.086–2.23, 0.113–2.94, 0.58–10.22, 0.19–24.9, 0.22–13.9 and 1.01–43.3 mg g⁻¹, respectively. The contents of caffeine and catechins followed the sequence: EGCG > EGC > ECG > EC > C > caffeine. The method was applied satisfactorily for the analysis of (+)-catechin, even at trace and ultra trace concentrations of catechins. The method was rapid, accurate, reproducible and ideal for routine analysis.     

Nutritive value of masau (Ziziphus mauritiana) fruits from Zambezi Valley in Zimbabwe

Ziziphus mauritiana (masau) fruits are consumed by many people in Zimbabwe. The fruits contribute significantly to people’s diet when they are in season. The objective of this study was to determine the nutritional content of the fruits and, hence, quantify their contribution to the diet. Samples of masau were collected in two seasons (August 2006 and August 2007). Both macronutrients and micronutrients were determined using standard AOAC methods of analysis. Dry matter content ranged from 21.1 ± 0.2 to 24.1 ± 0.3 g 100 g⁻¹ of edible portion of the sweet and sour fruits, and 84.8 ± 0.2 to 87.2 ± 0.2 g 100 g⁻¹ for the dried fruit. Crude protein per 100 g edible portion of dry weight ranged between 7.9 ± 0.0 and 8.7 ± 0.0 g, crude fat from 0.8 ± 0.0 to 1.5 ± 0.0 g, crude fibre from 4.9 ± 0.0 to 7.3 ± 0.0 g, ash between 3.0 ± 0.0 and 4.3 ± 0.0 g and carbohydrate between 79.5 ± 0.0 and 83.2 ± 0.0 g. The fruits were rich in vitamin C (15.0 ± 0.0–43.8 ± 0.02 mg 100 g⁻¹) and the energy values ranged between 1516.0 ± 1.73 and 1575.0 ± 2.3 kJ 100 g⁻¹. Furthermore, the fruits contained (mg 100 g⁻¹ of dry weight) potassium from 1865.0 ± 1.3 to 2441.0 ± 1.1, calcium from 160.0 ± 0.3 to 254.0 ± 0.1, sodium between 185.0 ± 0.1 and 223.0 ± 0.2, magnesium between 83.0 ± 0.0 and 150.0 ± 0.13 and phosphorous from 87.0 ± 0.1 to 148.0 ± 0.5. Manganese and copper contents ranged between 0.7 ± 0.03 and 1.6 ± 0.03, while iron and zinc ranged between 2.1 ± 0.43 and 4.3 ± 0.1, and 0.6 ± 0.0–0.9 ± 0.0 mg 100 g⁻¹ of dry weight, respectively. The masau fruit is therefore a good potential source of carbohydrates, proteins and micronutrients, such as calcium, potassium, sodium, phosphorous, copper, iron, Vitamin C and zinc.     

Evaluation of culture media for enumeration of Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium animalis in the presence of Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus

The study compared the growth capability of probiotic (Lactobacillus acidophilus La05, Lactobacillus casei Lc01 and Bifidobacterium animalis Bb12) and non-probiotic (Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus) cultures on twenty-one culture media grouped according to selectivity: non-selective agars, selective agars without antibiotics and MRS agars containing different combinations of lithium chloride, cystein, bile salts and antibiotics. Four of these media were selected for quantitative enumeration of L. acidophilus La05, L. casei Lc01, and B. animalis Bb12. The best culture media and incubation conditions for enumeration of the probiotic cultures were: B. animalis: MRS agar with dicloxacillin, 37 °C or 42 °C, anaerobiosis; L. acidophilus: MRS agar with bile salts, 37 °C or 42 °C, aerobiosis; L. casei: MRS agar with lithium chloride and sodium propionate, 37 °C or 42 °C, aerobiosis or anaerobiosis. Plating on MRS with glucose replaced by maltose, 37 °C or 42 °C, anaerobiosis, will distinguish probiotic from non-probiotic cultures. For enumeration of each probiotic in a mixed culture, the following media and incubation conditions were recommended: B. animalis: 4ABC-MRS, 42 °C, anaerobiosis, L. acidophilus: LC medium, 42 °C, aerobiosis or anaerobiosis and L. casei: LP-MRS, 42 °C, aerobiosis or anaerobiosis. In all experiments, differences in counts using pour plating or surface plating were not significant (P ≤ 0.05).     

The effects of temperature,chlorine and acids on the survival of Listeria and Salmonella strains associated with uncooked shrimp carapace and cooked shrimp flesh

The purpose of this study was to assess the influence of the association of Listeria and Salmonella with shrimp surfaces on the effects of temperature, chlorine and acids on their survival. Planktonic, attached and colonized cells of Listeria monocytogenes Scott A, L. monocytogenes V7, Salmonella Senftenberg 1734b and S. Typhimurium ATCC 14028 were challenged with high (50°, 60° and 70 °C) and low (4 °C) temperature, 100 ppm sodium hypochlorite solution, and acetic, hydrochloric and lactic acids (pH 4.0). Attached and colonized Listeria and Salmonella showed significantly greater (p < 0.05) resistance to heat (∼1.3–2.6 fold increase in D-values), hypochlorite (∼6.6 ≥ 40.0 fold) and acids (∼4.0–9.0 fold) than their planktonic counterparts. There were no significant differences (p > 0.05) in the survival of planktonic, attached or colonized cells of Listeria and Salmonella stored under refrigerated conditions. The association of Listeria and Salmonella with shrimp surfaces enhances their resistance to heat, chlorine and acids. Both attachment to, and subsequent colonization of, shrimp surfaces by pathogens may reduce the efficacy of methods used in their control. Strategies to reduce attachment of these pathogens to shrimp are required to assure safety of this product.     

β-Lactoglobulin nanofibrils: Effect of temperature on fibril formation kinetics, fibril morphology and the rheological properties of fibril dispersions

Almost all published studies of heat-induced β-lactoglobulin self-assembly into amyloid-like fibrils at low pH and low ionic strength have involved heating at 80 °C, and the effect of heating temperature on self-assembly has received little attention. Here we heated β-lactoglobulin at pH 2 and 75 °C, 80 °C, 90 °C, 100 °C, 110 °C or 120 °C and investigated the kinetics of self-assembly (using Thioflavin T fluorescence), the morphology of fibrils, and the rheological properties of fibril dispersions.Self-assembly occurred at all temperatures tested. Thioflavin T fluorescence increased sigmoidally at all temperatures, however it decreased sharply with >3.3 h heating at 110 °C and with >5 h heating at 120 °C. The sharp decreases were attributed partly to local gelation, but destruction of fibrils may have occurred at 120 °C. Thioflavin T fluorescence results indicated that maximal rates of fibril formation increased with increasing temperature, especially above 100 °C, but fibril yield (maximum Thioflavin T fluorescence) was not affected by temperature.At 100 °C and 110 °C, fibrils were slightly shorter than at 80 °C, but otherwise they looked very similar. Fibrils made by heating at 120 °C for 1 h were also similar, but heating at 120 °C for 8 h gave predominantly short fibrils, apparently the products of larger fibrils fragmenting. Heating at 100 °C gave consistently higher viscosity than at 80 °C, and heating for >2 h at 120 °C decreased viscosity, which may have been linked with fibril fragmentation seen in micrographs.     

Determination of metal contaminations in sea foods from Marmara,Aegean and Mediterranean seas: Twelve fish species

The concentrations of cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead and zinc were determined by ICP-AES in muscles and livers of 12 fish species sampled from the Marmara, Aegean and Mediterranean seas of Turkey. Iron showed the highest levels in examined tissues of all fish species. Following Fe, Zn generally showed the second highest levels. Metal concentrations in edible parts of fish species were 0.02–0.37 mg kg⁻¹ for cadmium, 0.04–0.41 mg kg⁻¹ for cobalt, 0.04–1.75 mg kg⁻¹ for chromium, 0.32–6.48  mg kg⁻¹ for copper, 7.46–40.1 mg kg⁻¹ for iron, 0.10–0.99  mg kg⁻¹ for manganese, 0.02–3.97 mg kg⁻¹ for nickel, 0.33–0.86 mg kg⁻¹ for lead, 4.49–11.2 mg kg⁻¹ for zinc, respectively. All metal concentrations in livers were higher than those in muscles. In some stations, cadmium and chromium concentrations in both muscles and livers, and lead levels in livers of the examined species were higher than permissible safety levels for human uses.     

Enriching the egg yolk in n − 3 fatty acids by feeding hens with diets containing horse fat produced in Uruguay

The present study was conducted to evaluate the ability of horse fat produced in Uruguay, compared with other lipid sources supplemented in the diet of laying hens, to modify the lipid composition and the n − 6/n − 3 fatty acid ratio of the produced eggs. For this purpose, 60 laying hens (Gallus domesticus) were fed for 30 days with five experimental diets (12 hens/diet) containing 3% sunflower oil (SO), rice oil (RO), beef tallow (BT), pressed-fat (PF), obtained by pressing fat from bovine viscera, and horse fat (HF) obtained from horse bone medulla. Throughout the trial, feeding rate, shell index, weight and total lipid contents of eggs, were not affected by the different diets. Feeding on the SO and RO diets significantly increased the amount of linoleic acid of the egg, although it was lower in the RO than in the SO eggs. Diet BT did not affect the saturated fatty acid content of the yolks. The diets with animal fats containing 18:3n − 3 (diets PF and HF), resulted in a significant increase in the n − 3 fatty acid contents of the eggs, through an increase of linolenic (18:3n − 3) and docosahexaenoic acid (DHA, 22:6n − 3) contents. Eggs from hens fed the HF diet showed increased linolenic acid (46 mg/yolk) and DHA (71 mg/yolk, 1.7% of total fatty acids) contents. These levels were obtained after two weeks of feeding. Moreover, the fatty acid profiles of eggs from treatment HF were not significantly affected by thermal treatment of the yolks. In conclusion, the fat from horse bone medulla, as produced in Uruguay, can be considered as a suitable lipid source for diets of laying hens, to modify the nutritional composition of the eggs in n − 3 PUFA content, especially DHA, and consequently, the n − 6/n − 3 fatty acid ratio.