Cultivation of the oyster mushroom (Pleurotus ostreatus) on lignocellulosic waste

The establishment of a small-scale production facility for Pleurotus ostreatus is described and environmental and yield data are presented. The average yield was c. 50% fresh weight mushroom/dry weight substrate when grown on 40% cocoa shell waste, 40% softwood sawdust, 19% oatmeal and 1% carboxymethyl cellulose. The mushroom fruited when daily temperatures ranged between 11 and 27°C.     

榆黄菇多糖提取工艺优化及其免疫调节活性评价

以榆黄菇为研究对象,对榆黄菇多糖（PCP）提取工艺进行优化、纯化、测定单糖组成和分子量,再对其体外免疫活性进行评价。在单因素基础上通过响应面法确定榆黄菇多糖最优提取工艺为：提取温度59.81 ℃,提取时间2.40 h,液料比29.91 mL/g,在此条件下,预测得率为18.82%,实际得率为18.60%。经DEAE-Sepharose Fast Flow柱层析从榆黄菇多糖中分离纯化出3个多糖组分（PCP-1、PCP-2、PCP-3）,采用离子色谱法和高效凝胶渗透色谱法分析多糖成分和分子量,得出PCP-1由半乳糖组成,分子量为 1.90×104 u;PCP-2由半乳糖和葡萄糖组成,摩尔比为4.36:5.64,分子量2.76×104 u;PCP-3由岩藻糖、盐酸氨基葡萄糖、半乳糖、葡萄糖和葡萄糖醛酸组成,其摩尔比为0.07:0.11:0.51:7.46:1.85,分子量为4.81×104 u。通过体外试验评估PCP对巨噬细胞RAW264.7免疫调节活性。结果表明,PCP-1、PCP-2和PCP-3多糖质量浓度在25~200 g/mL范围内对巨噬细胞RAW264.7无毒性并具有一定增殖作用、显著提高了NO释放量并增强了巨噬细胞RAW264.7的吞噬能力。当PCP-1、PCP-2和PCP-3多糖质量浓度为200 g/mL时,巨噬细胞RAW264.7 NO释放量达到最大值,分别为11.40、11.56、11.76 moL/L。该研究结果可为榆黄菇的精深加工综合利用提供理论依据。     

Giant oyster mushroom,Pleurotus giganteus (Agaricomycetes): Current status of the cultivation methods,chemical composition,biological, and health-promoting properties

Pleurotus giganteus (Berk.) Karunarathna & Hyde is one of the largest edible mushrooms which can be found either in groups or solitary and in soil and buried woods, but seldom in grassland. It has been recorded in Southeast Asia, Australasia, and China by either its common names or local names. Previously known as Lentinus/Panus giganteus, its unique physical characteristics and the utilization of molecular tools have since anchored its taxonomical position in the Pleurotus genus. A sawdust-based substrate coupled with soil casing method is described as a standard cultivation procedure for P. giganteus. The basidiocarp of P. giganteus is found to be rich in carbohydrates, proteins, polyunsaturated fatty acids, and polysaccharides. Both ethanol and aqueous extracts of P. giganteus have been studied in vitro for its antioxidative, antifungal, anticancer, hepatoprotective, and neurite outgrowth capabilities. The review covers the optimum cultivation methods of P. giganteus, as well as its various biological activities and medicinal properties that have been studied by different approaches. Available data in regards to the chemical compounds present in P. giganteus are also compiled for future references. Overall, both in vitro and in vivo studies have shown significant bioactivity comparable to other recognized Pleurotoid mushrooms.     

Development and quality evaluation of a cereal-based breakfast product from yellow maize (Zea mays), sesame (Sesamum indicum) and mushroom (Pleurotus ostreatus) flour blends

Composite flours were prepared from blends of yellow maize (Zea mays), sesame seed (Sesamum indicum) and oyster mushroom (Pleurotus ostreatus) powder in the ratio of 80:20:0; 75:20:5; 70:20:10; 65:20:15 and 60:20:20, respectively to produce the cereal-based breakfast product coded as YSB, SMB, TMB, PMB and OMB with YSB as the control. The breakfast cereals were produced by hydration and toasting of yellow maize and sesame to 160°C for 25 min and blended together with oven-dried and packaged oyster mushroom. The developed products were analysed for proximate, vitamins, minerals and sensory properties. The proximate composition (%) of different blends ranged as moisture (4.07–7.08), ash (3.09–2.28), crude fat (16.04–12.83), crude fibre (4.30–8.22), protein (16.14–22.54), carbohydrate (56.34–47.04) and energy (434.34–393.83 Kcal). Vitamin A (7.99–5.98 mg/100 g), vitamin B₁ (0.08–0.42 mg/100 g), vitamin B₂ (0.06–0.15 mg/100 g), vitamin B₃ (1.91–4.52 mg/100 g) and vitamin C (3.55–3.32 mg/100 g) were u while minerals (mg/100 g) were calcium (75.31–58.02), potassium (0.65–4.01), magnesium (12.25–12.62), iron (1.21–4.15) and zinc (0.40–1.32). Sensory scores revealed that the cereal-based breakfast product were acceptable to the panellist with oyster mushroom supplementation up to 10%.     

Breeding of Pleurotus florida (oyster mushroom) for phenotypic pigmentation and high yield potential

BACKGROUND: Cross‐hybridisation is a technique for exchange of genetic material between two compatible nuclei to develop a recombinant genome with a probable expression for a desirable trait. This technique as an example of classical genetics has been applied in a heterothallic bifactorial/tetrapolar fungus Pleurotus florida. It has worked successfully during this study in a small number of experiments. RESULTS: Fruit bodies from the Pleurotus florida PAU‐5 were allowed to shed their basidiospores on filter paper under aseptic conditions. Forty‐nine monokaryons were isolated from three spore prints, namely Ja, Jb and K. Three hundred and fifty‐six crosses were laid to result in five compatible reactions (PFJ4, PFJ9, PFJ11, PFJ13 and PFJ14). The fruit bodies of the hybrid dikaryon PFJ4 were found to show grey pigmentation. The hybrid dikaryons PFJ11 and PFJ14 grew faster in wheat straw substrate to take 39 and 41 days, respectively, for complete mycelial impregnation as compared to the parent, PAU‐5 (48 days). The dikaryon PFJ11 out‐yielded the parent by giving 34.2% biological efficiency compared to 29.8% for the parent. CONCLUSION: Through cross‐hybridisation various changes at the genetic level are possible, showing altered phenotypic expression of the characters, such as change in fruiting efficiency and variability in fruit body characteristics (e.g., pileus shape and pigmentation). This technique can also be applied to other crops to improve their yield potential and bring about desirable phenotypic changes. Copyright © 2008 Society of Chemical Industry     

Amino acid and total protein content of the edible mushroom Cantharellus cibarius (Fries)

It is difficult to determine total protein content in fungi, mainly because chitin and other nitrogenous compounds interfere with total nitrogen analysis (eg Kjeldahl analysis) which is commonly used. Therefore, a few different methods have been compared, and total amino acid concentration and composition in the edible mushroom Cantharellus cibarius (Fries) have been analysed using one sophisticated and one rough method based on acid hydrolysis and ninhydrin. For fungal material, it is better to analyse total amino acids. Only 99 g kg^?1 dry weight of C cibarius was protein which implies that former values based on total N analysis given in literature are 70–200% too high. The nutritional value of mushrooms should therefore not be over emphasised, even though the protein content is higher than that of most vegetables.     

Sensory and Chemical Analyses of Oyster Mushrooms (Pleurotus sajor-caju) Harvested from Different Substrates

ABSTRACT: The sensory characteristics of dehydrated oyster mushrooms harvested from 8 different substrates and chemical compounds related to sensory attributes were analyzed and compared. The sensory attributes rubbery, sweet pea, and bitter as well as the chemical content of total lipids, palmitic acid, benzaldehyde, mannitol, 14 free amino acids, and 5'-adenosine monophosphate were found to be significantly affected by the substrates used for cultivating oyster mushrooms. This study demonstrated that the substrate composition for oyster mushroom production had minor effects on sensory and quality characteristics. Chemical analysis indicated that benzaldehyde, some free amino acids, 5'-cytosine monophosphate (CMP), 5'-guanosine monophosphate (GMP), and 5'-inosine monophosphate (IMP) showed correlations with the sensory attributes perceived by the sensory panel; however, some of these compounds were not detected in all samples.     

Molecular Weight Affected Antioxidant,Hypoglycemic and Hypotensive Activities of Cold Water Extract from Pleurotus citrinopileatus

Cold water extract of P. citrinopileatus (CWEPC) was fractioned into 4 fractions, PC‐I (<1 kDa), PC‐II (1‐3.5 kDa), PC‐III (3.5‐10 kDa), and PC‐IV (>10 kDa), by ultrafiltration. The antioxidant activities, the inhibition of pancreatic α‐amylase, intestinal α‐glucosidase, and hypertension‐linked angiotensin converting enzyme (ACE), as well as the contents of polysaccharides, protein, and phenolic compounds of 4 fractions were determined. The results showed that lower MW fractions exerted a higher antioxidant activity, which was correlated to phenolic contents. The high molecular fraction (PC‐IV) exhibited significantly higher inhibitory activity on α‐amylase, α‐glucosidase, and ACE compared to CWEPC and the other 3 lower MW fractions (<10 kDa), which was more related to protein contents. The inhibition capability of CWEPC and PC‐IV on α‐amylase activity was 1/13.4 to 1/2.7 relative to that of acarbose, respectively. Kinetic data revealed that PC‐IV fraction followed a noncompetitive inhibition pattern on α‐glucosidase activity. The study demonstrated that various MW fractions and types of components contribute to different biological functions of P. citrinopileatus and it is protein constituents but not peptides responsible for the hypoglycemic potential of CWEPC.     

Biochemical changes associated with mushroom browning in Agaricus bisporus (Lange) Imbach and Pleurotus florida (Block & Tsao): commercial implications

Biochemical changes associated with mushroom browning in Agaricus bisporus and Pleurotus florida were studied. With increasing storage temperature from 0 to 25 °C there was an increase in phenol oxidase activity up to 15 °C followed by a decrease at 25 °C in both mushrooms. Loss of water content in fresh mushrooms had a direct relationship with phenol oxidase activity, which could be correlated with the visual degree of mushroom browning. A bisporus displayed higher phenol oxidase activity, about two to three times that of P florida. The phenol oxidase activity in both mushroom varieties was studied on a range of phenolic compounds with diverse functional groups. A bisporus exhibited intense reactions to tyrosine and catechol, while P florida did so to guaiacol and catechol. The two mushrooms differed in the degree of their oxidation reactions relative to the functional groups. In A bisporus the skin had more phenolics than the flesh; P florida contained fewer phenolics, while the stalks of both mushrooms had low phenolics contents. FTIR spectral studies of intact mushrooms during browning showed a characteristic decrease in phenolic hydroxyls; first‐derivative spectra were used to assess relative peak intensities. Of the chemicals tested for their effect on phenol oxidase activity, 0.1 M sodium carbonate favoured the immediate development of an orange chromogen in P florida, while mild alkaline solutions favoured the enzyme activity, and acidic solutions at the 0.1 M level completely inhibited the browning reaction in both mushrooms. Copyright © 2003 Society of Chemical Industry     

The fate of Cry1Ac Bt toxin during oyster mushroom (Pleurotus ostreatus) cultivation on transgenic Bt cottonseed hulls

BACKGROUND: In China, mushrooms are often cultivated on cottonseed hulls, and spent substrates from their cultivation are used as cattle feed. As the area planted to Bacillus thuringiensis (Bt) cotton in China increases, hulls from transgenic Bt cottonseed are being increasingly used as a substrate for edible mushroom cultivation. The objective of this research was to determine whether Bt toxin was transmitted to mushrooms cultivated on transgenic Bt cottonseed hulls or retained in the spent substrate. RESULTS: Bt toxin was still present in transgenic Bt cottonseed hulls after chemical (carbendazol) treatment but not after heat (100 °C) treatment before mushroom fungus inoculation. When mushroom was cultivated on carbendazol‐treated substrates, Bt toxin level in the substrates fell below the detection limit (1.5 ng Cry1Ac per g fresh weight) in 15 days. CONCLUSION: Bt toxin was not transmitted to mushrooms during cultivation on transgenic Bt cottonseed hulls. Copyright © 2007 Society of Chemical Industry     

超滤法浓缩富集牡蛎蛋白抗氧化活性肽

为研究牡蛎蛋白酶解产物中发挥抗氧化活性的肽片段,采用超滤的方法对其进行初步分离富集,测定了各级组分的体外抗氧化能力和氨基酸组成。结果表明:<4000u超滤液对羟自由基、DPPH自由基和超氧自由基清除活性的IC50值分别为17.29、2.82、7.02mg/mL,对肝脂质过氧化抑制作用的IC50值为14.40mg/mL,均低于原液和其他超滤组分;<4000u超滤液的还原力均高于同浓度的原液和其他超滤组分。经氨基酸分析,超滤后组氨酸、脯氨酸、甲硫氨酸、半胱氨酸、酪氨酸、色氨酸及苯丙氨酸的含量得到了富集。<4000u的超滤液经凝胶层析后,活性部分主要集中在550～3890u。      

Physicochemical properties of hydrophobic and hydrophilic peptides from oyster protein

The physicochemical properties of the hydrophilic peptides (HIPs) and the hydrophobic peptides (HOPs) from the oyster protein hydrolysates (OPHs) were analysed. The technology of high-performance liquid chromatography and dynamic light scattering was used to determine the molecular weights and the particle sizes of HIP and HOP. About 60–70% of them had a molecular weight below 500 Da and the particle size was all about 100 nm, which were smaller than OPH. Furthermore, compared with OPH and HIP, HOPs have obvious advantages in surface hydrophobic and emulsifying properties because they have more hydrophobic groups on the surface. The emulsifying activity and emulsion stability of HOP can be significantly improved from 3.80 to 42.88 m² g⁻¹ and 131.17–163.70 min, respectively, because of its high surface hydrophobicity. Thus, our results suggest that HOPs have a great potential to be developed as an emulsifier.     

Effects of different agro-industrial waste as substrates on proximate composition,metals, and mineral contents of oyster mushroom (Pleurotus ostreatus)

The use of agro-industrial waste as substrates for mushroom cultivation is considered a promising management strategy for reducing and valorising these wastes, simultaneously reducing the cost of mushroom cultivation. In this study, oyster mushroom Pleurotus ostreatus were cultivated on twelve substrates composed of either tea waste, lime sawdust, alder sawdust, hornbeam sawdust/shaving, wheat stalk-straw, wheat bran or their composite to determine the proximate composition and accumulation of thirteen elements in their fruiting bodies. The proximate composition of P. ostreatus did not show a significant difference, regardless of the employed substrate. (one-way manova ; F_{(66, 107)} = 1.329, Wilk’s λ = 0.041, P > 0.05). However, their chemical element contents show a statistically significant difference (one-way manova ; F_{(132, 418)} = 32.163, Wilk’s λ = 0.000, P < 0.05). These results were supported by discriminant function and principal component analyses. The highest mean concentrations of six of twelve elements (i.e., Ca, Mg, Na, Zn, Cd and Cr) were recorded in P. ostreatus cultivated on the lime-sawdust substrate. Three health indices viz., estimated daily intake, target hazard quotient (THQ) and total THQ were applied to determine the risk to human health via the consumption of P. ostreatus, suggesting that they are safe for human consumption.     

An environmentally friendly and cost effective technique for the commercial cultivation of oyster mushroom [Pleurotus florida (Mont.) Singer]

BACKGROUND: The existing protocol for the cultivation of oyster mushroom (Pleurotus florida) in polyethylene bags leads to environmental pollution amounting to 18 g of polyethylene per 450 g of mushroom, which is the average biological efficiency achieved from a bag. Thus the projected annual global pollution amounts to 2 million tones, corresponding to the production of 48 million tones. Experiments were conducted at Kerala Agricultural University, India, to formulate an oyster mushroom cultivation strategy that reduces this pollution level. RESULTS: Pooled results of experiments at the institute's and farmers' units have shown that reusable plastic buckets having perforations of 1.5 cm × 1.0 cm throughout the side walls could be used to substitute polyethylene bags, while following the standard cultivation protocols. Cultivation in perforated buckets has recorded a biological efficiency of 435.69 ± 56.75 g in 47.07 ± 5.22 days against 459.11 ± 53.52 g in 38.05 ± 4.54 days in polyethylene bags. The rate of contamination in buckets was significantly lower than that in bags: 9.28 ± 2.12 and 12.60 ± 3.73% respectively. CONCLUSION: Reusable plastic buckets with perforations on the side walls could be used to substitute the conventional polyethylene bags in oyster mushroom cultivation, with no significant difference in yield. Losses due to slight increase in crop duration in buckets will be compensated with a lower rate of contamination. For a unit having a daily output of 100 kg, it was estimated that during 10 years of permanent cultivation following this technique, the cost of cultivation could be reduced to one‐tenth and the environmental pollution reduced by at least 730 000 non‐degradable polyethylene bags. © 2012 Society of Chemical Industry     

Sensory analysis and fruiting bodies characterisation of the edible mushrooms Pleurotus ostreatus and Polyporus tenuiculus obtained on leaf waste from the essential oil production industry

The present investigation aims to examine if waste from the essential oil industry (Laurus nobilis and Eucalyptus cinnerea) can modify the sensory attributes of dried Pleurotus ostreatus and Polyporus tenuiculus. Moreover, the conversion percentage from dry substrate weight to fresh mushroom weight (biological efficiency) and fresh fruiting body characterisation were evaluated. It was possible to obtain fruiting bodies in both aromatic substrates. This study demonstrated that the substrate composition had effects on the sensory and quality characteristics of the mushrooms. The use of aromatic plant wastes increased the intensities of the brown colour, sour, ‘mushroom’ flavour and springiness, and decreased the intensities of the bitterness and hardness. In addition, significant differences between species were observed. Pleurotus ostreatus had the highest ‘mushroom’ flavour, pungency and sour intensities, and P. tenuiculus was recognised for its cereal flavour, hardness, fibrous texture and springiness.     

Nutrient and antinutrient distribution of edible mushroom, Pleurotus tuber-regium (fries) singer

Edible mushroom Pleurotus tuber-regium, separated into cap, stalk, and tuber, was analysed. The macronutrient profile (g/100 g) showed crude protein ranging from 4.1 to 13.8, with the highest concentration in the cap (13.8) than any of the other parts and total carbohydrates from 34.0 to 56.2, while the crude fat and ash contents were generally low. Potassium, the most abundant nutritive element was found to be the highest concentration (mg/g) in the stalk (3.3) while copper was found in trace amounts in all the parts. The total cyanide (mg/100 g), phytate (mg/100 g) and tannin (%TA) concentrations were all below levels considered harmful. Amino acids analysis show that the protein contained all essential amino acids while the calculated amino acids scores showed the sulphur containing amino acids to be most limiting. The foregoing highlights the high nutritive values of the major parts of the edible mushroom, Pleurotus tuber-regium.     

富硒平菇蛋白测定与氨基酸成分分析

目的:研究培养料添加10～50mg/kg不同浓度无机硒后,所采收的富硒平菇中蛋白的含量,并对菇体中硒含量为7～10μg/g干重(10mg/kg处理组),可直接上市供鲜食的富硒平菇组进行氨基酸成分分析。方法:考马斯亮蓝G-250法测定富硒平菇干粉的可溶性蛋白,凯氏定氮法测定总蛋白含量,氨基酸自动分析仪进行氨基酸成分分析。结果:富硒平菇干粉中可溶性蛋白含量都明显高于对照组,最高达对照的2.25倍;可直接上市供鲜食的富硒平菇体内的氨基酸成分分析:人体必需的7种氨基酸(色氨酸没测定)占氨基酸总量的47.44%,半必需氨基酸占氨基酸总量的14.39%,支链氨基酸占氨基酸总量的20.37%。结论:富硒平菇是一种具有较高的保健和药用开发价值的功能性产品。     

Effects of Phosphoryl Oligosaccharides of Calcium (POs-Ca) on Mycelial Growth and Fruiting Body Development of the Edible Mushroom,Pleurotus ostreatus

Phosphoryl oligosaccharides of calcium (POs-Ca) is a calcium salt of phosphoryl maltooligosaccharides made from potato starch. POs-Ca is highly water-soluble and can supply both the calcium ion and acidic oligosaccharides in an aqueous solution. In this study, we investigated the effects of POs-Ca on the mycelial growth and fruiting body yield of Pleurotus ostreatus , which is one of the most widely cultivated edible mushrooms in the world. We cultivated the mushroom using both potato dextrose agar (PDA) medium and sawdust-based medium, with added calcium salts. The addition of POs-Ca into the PDA medium with a calcium concentration of 10 mg increased mycelial growth significantly ( p < 0.05, vs . control). POs-Ca addition to the sawdust-based medium at concentrations of 1.0 to 3.0 g/100 g medium increased the amount of calcium in the fruiting bodies but did not affect the length of the cultivation period or the weight of the fruiting body. The calcium content in the fruiting body increased 12-fold when compared to the control. On the other hand, neither the CaHPO ₄ ･2H ₂ O group nor the CaHPO ₄ ･2H ₂ O with oligosaccharides group showed changes in the calcium content of the fruiting bodies. Our results indicate that the use of POs-Ca in mushroom cultivation allows for the possibility of developing new functional foods like calcium-enriched edible mushrooms. This is the first report describing the effects of POs-Ca on mushroom cultivation.