Evaluation of Pleurotus ostreatus and Pleurotus sajor-caju nutritional characteristics when cultivated in different lignocellulosic wastes

Fungi of Pleurotus genus present a high content of proteins and vitamins and low content of fat. Based on these facts, this work aimed to evaluate some nutritional characteristics of fruiting bodies of Pleurotus ostreatus and Pleurotus sajor-caju after the first harvest, using rice straw and banana straw as substrates. Both species presented a higher content of ash in the rice straw substrate (5.86% average) than in the banana straw (5.36%). P. sajor-caju CCB 019 showed higher moisture and fibre content when cultivated in rice straw (88.08% and 9.60%, respectively) than in banana straw (83.17% and 7.60%, respectively). The other parameters were not influenced by the cultivation substrate. The protein content (from 1.54% to 3.10%) of Pleurotus fresh fruiting bodies proved to be similar to, or even higher than, the values observed in various vegetables but lower than the protein contents of eggs, meat and cheese.     

甜菜废丝栽培平菇的初步研究

本文探讨了利用甜菜废丝栽培平菇的产量和效益,通过不同培养料配方和栽培方法的研究,初步筛选了适宜北方地区栽培平菇的合理配方及栽培方法,即甜菜废丝86％、棉籽壳或麸皮10％、白糖0.5％、尿素1％、CaCO_3 2％、KH_2PO_40.5％,方法为熟料袋栽。     

Trace elements in sewage sludges

Analyses of 42 sewage sludges from rural and industrial towns in England and Wales show very large concentrations of certain trace elements. Total contents of 5% Zn, nearly 1% Cr and Cu and 0.5 % Ni were found in certain dried sludges. Total contents of Cu, Sn and Zn and, to a lesser extent, Ag, Bi and Pb were much greater than the levels of these elements in soils. Total Cr and Ni were very high in a small number of samples. Acetic acid-soluble Zn and Cu levels were generally very much greater than in soils. Overall, Mn, Ni and Zn had considerably higher percentage solubilities than Cr, Cu, Mo, Pb, Sn and V. Zinc, Cu and Ni appear to be the elements most likely to give rise to toxicity problems in plants due to the use of sewage sludge as a soil additive.     

Trace elements in Slovenian poultry tissues

In this paper, the contamination of poultry tissues by trace elements in Slovenia is examined from a public health standpoint. During systematic veterinary and sanitary monitoring of foodstuffs of animal origin from 1997 to 1999, 21 poultry meat samples, 70 poultry liver tissue samples, and 184 poultry kidney tissue samples were examined for Pb, Cd, and Hg contents. The levels of poultry tissue contamination in six regions of Slovenia were determined. All samples met Slovenian standards except one poultry kidney tissue sample, which exceeded the Hg level allowed. The difference between chicken and turkey contamination levels was statistically significant (P < 0.05) only for Cd content in kidney tissues. Poultry kidney tissue Cd contents differed for different geographical regions (P < 0.05).     

泸州桂圆果肉中微量元素含量分析

目的确定泸州产桂圆肉中微量元素的含量。方法采用微波消解,电感耦合等离子体光谱质谱联用仪和电感耦合等离子体光谱仪对桂圆肉中16种微量元素进行检测。结果泸州本地产桂圆肉中钾平均含量高达20 g/kg;其次是钙和镁,平均约为600 mg/kg;钠的平均含量约40 mg/kg;铁、硼、铜、锌、含量均大于10 mg/kg、锰的含量约为5 mg/kg。同时含有微量的镍、钼、钴、硒、铬、锡;在方法检出限范围内,未检测到钒。结论泸州桂圆中含有人体必需的微量元素,同时含有丰富的钾、钙、镁。     

Trace elements in two pulverized coal-fired power stations

Beside major pollutants (particulates, carbon, sulfur, and nitrogen oxides), coal combustion generates emissions of potentially toxic trace elements. The current work focuses on predicting the fate of eight trace elements (As, Cd, Hg, Ni, Pb, Se, V, and Zn) in power stations that fire pulverized coal and are equipped with flue gas scrubbers. The core of the study is global equilibrium analysis carried out with the aid of three extensive databases. The first set of equilibrium constants describes conditions prevailing in the furnace and the flue gas duct, while the second set describes reactions in the flue gas scrubber. Melting behavior of ash and solubility of trace elements within the slag are described as a third set of data. To test the modeling approach taken in this paper, the predicted overall partitioning of trace elements is compared with measured data from two full-scale facilities. The results of the study indicate that As, Cd, Ni, Pb, V, and Zn are captured in the fly ash, and that the fate of these element correlates with the overall particle capture of the power plants. Calculations for the flue gas scrubber facilities show that nonvolatile trace elements are likely to dissolve in the scrubber solution, and that capture of these elements likewise is correlated with the overall particulate behavior. Theoretical predictions of the melting behavior indicate that As, Ni, Zn, and to some extent Pb are likely to dissolve in the molten ash.     

Toxic and essential elements in soft wheat grain cultivated in Serbia

A survey was carried out with the aim of assessing the level of some toxic (Cd, Pb, Hg and As) and essential (Cu, Zn, Fe and Mn) elements in wheat grown in Serbia. A total of 433 samples of soft winter wheat grain from all the Serbian wheat-growing regions were pooled into 52 representative samples for 2002 harvest. After wet digestion, Cd, As, and Pb were determined by graphite furnace atomic absorption spectrometry (GFAAS), whereas Cu, Zn, Fe and Mn were determined by flame atomic absorption spectrometry (FAAS). Vapour generation accessory was used for Hg determination. The mean and median contents of all samples were (on a dry weight basis) 29 and 24 g/kg for Cd, 137 and 87 g/kg for Pb, 7 and <0.1 g/kg for Hg, 55 and 59 g/kg for As, 4.1 and 4.0 mg/kg for Cu, 24 and 24 mg/kg for Zn, 53 and 53 mg/kg for Fe, 34 and 33 mg/kg for Mn. The calculated mean and median levels of contamination were compared with the recommended or regulated maximum levels according to the European Commission and the national legislation. The average intake of eight selected elements from wheat-based products was estimated for the Serbian population.     

Effect of chemical preservatives on shelf life of mushroom (Pleurotus ostreatus) cultivated on cassava peels

Short shelf life is a major impediment to the processing and distribution of mushroom. The effect of chemical preservatives on some quality attributes of mushroom during storage was investigated. Mushroom were soaked in four preservatives at two concentrations for 10 mins, packaged, stored at 4 °C for 30 days and analysed at intervals for their microbial population, colour, firmness and weight loss. Sodium benzoate (0.05%, 0.1%) lost its preservative effect on all the micro‐organisms enumerated after 3 days, and samples treated with 0.1% potassium sorbate had the lowest microbial load at the end of the storage period. Change in colour of the potassium sorbate (0.1%)‐treated sample was lower than and significantly different from the citric acid (2%, 4%)‐treated samples. The values of the firmness of the 4% citric acid preserved mushroom were significantly different (P ≤ 0.05) from other samples throughout the storage period. There was a significant negative correlation (r = ?0.807, P < 0.01) between the firmness and weight loss of the preserved mushroom. Potassium sorbate (0.1%) and citric acid (4%) extended the shelf life of mushroom for 24 days.     

不同菌材栽培糙皮侧耳营养品质综合评价

摘 要：目的 分析不同菌材栽培糙皮侧耳(Pleurotus ostreatus)生长及营养品质差异,并对其营养品质进行综合评价。方法 以贵州5种常见菌材锥栗(Castanea henryi)、构树(Broussonetia papyrifera)、刺槐(Robinia pseudoacacia)、光皮桦(Betula luminifera)、青冈(Quercus glauca)为主要培养料栽培糙皮侧耳,对糙皮侧耳菌丝生长、子实体主要农艺性状及营养品质进行分析。结果 糙皮侧耳在光皮桦培养基上菌丝生长速率更快,在锥栗和刺槐栽培基质中子实体主要农艺性状更好。刺槐栽培基质中糙皮侧耳子实体粗蛋白、Cu、Zn、K元素含量最高,锥栗栽培基质中糙皮侧耳子实体多糖、Na、Mg、Fe、Ca元素含量最高。以5种菌材栽培的糙皮侧耳子实体总氨基酸、必需氨基酸及总药用氨基酸均为刺槐>青冈>光皮桦>构树>锥栗。5种菌材栽培的糙皮侧耳子实体呈味氨基酸主要为甜味和苦味氨基酸,其中以光皮桦栽培的糙皮侧耳子实体鲜味和甜味氨基酸含量最高。必需氨基酸营养品质评价及营养品质综合评价结果表明刺槐栽培糙皮侧耳子实体综合营养品质更好。Fe、苏氨酸、丙氨酸、谷氨酸、精氨酸、天冬氨酸、组氨酸、Zn和多糖是5种菌材栽培的糙皮侧耳子实体主要差异营养成分。相关性分析结果显示菌材营养成分主要与糙皮侧耳菌丝生长、子实体主要农艺性状和矿物质元素含量显著相关。结论 不同营养成分的菌材对糙皮侧耳子实体生长和营养品质的影响不同,刺槐更适合作为生产糙皮侧耳主栽菌材。     

Phenolic profiles and antioxidant activity of litchi pulp of different cultivars cultivated in Southern China

The phenolic profiles and antioxidant activity of litchi pulp of 13 varieties were investigated. The free, bound and total phenolic contents were 66.17–226.03, 11.18–40.54, and 101.51–259.18 mg of gallic acid equivalents/100 g, respectively. The free, bound and total flavonoid contents were 16.68–110.33, 10.48–22.75, and 39.43–129.86 mg of catechin equivalents/100 g, respectively. Free phenolics and flavonoids contributed averagely 80.1% and 75% to their total contents, respectively. Six individual phenolics (gallic acid, chlorogenic acid, (+)-catechin, caffeic acid, (?)-epicatechin, and rutin) were detected in litchi pulp by HPLC. The contents of each compound in free and bound fractions were determined. Significant varietal discrepancy in antioxidant activity was also found by FRAP and DPPH scavenging capacity methods. Antioxidant activity was significantly correlated with phenolic and flavonoid contents. Thus, phenolics and flavonoids exist mainly in the free form in litchi pulp. There were significant varietal differences in phytochemical contents and antioxidant activity of litchi pulp.     

柴达木枸杞叶汁矿质元素含量测定与分析

目的:研究青海高原特有的枸杞叶中矿质元素含量,为枸杞叶的开发利用,选择枸杞叶原料提供科学依据。方法:选择青海省海西州诺木洪农场不同生长时期(6月、8月和10月)的枸杞叶,通过慢速榨汁机榨取枸杞叶汁,分为3组,采用原子吸收分光光度法,测定枸杞叶汁中矿质元素钙、铜、锌、铁、锰、钠和钾的含量,并对测定结果进行统计分析,从而探讨不同生长时期的枸杞叶汁中矿质元素含量的差异。结果:分析结果显示,诺木洪农场种植区枸杞叶汁矿质元素含量排序依次为钙>钠>钾>铁>锰>铜>锌。其中,6月组生长期的枸杞叶汁中的钾、铁、铜和锌元素含量均显著高于8月组和10月组(P<0.05)。而8月组和10月组生长期的枸杞叶汁中的钙、锰和钠元素含量显著高于6月组(P<0.05)。结论:6月生长期的枸杞叶更有利于开发铁、铜和锌的补充剂;而10月生长期的枸杞叶中钙、钠和钾的含量较高,更有利于研发钙的补充剂和天然碱性食品。