辽宁省不同地区几种食用菌重金属含量测定及质量评价

对食用菌重金属含量测定和污染状况分析,探讨环境污染因素对食用菌吸收重金属的影响。采用微波消解法对食用菌进行处理,应用ICP-AES法测定了Ni、Cr、Pb、Cd、As、Hg六种重金属元素的含量。结果表明,调查的51份样品中香菇、平菇、杏鲍菇、茶树菇、双孢菇、黑木耳、鸡腿菇、蛹虫草重金属合格率均为97%以上;Ni、As含量在个别香菇和黑木耳中超标,但超标量很小;个别平菇、香菇、黑木耳、鸡腿菇有Pb的检出但不超标;平菇、香菇、茶树菇、黑木耳有Cd的检出但不超标;平菇、香菇、杏鲍菇、茶树菇、黑木耳、鸡腿菇有Cr的检出但不超标;所有样品中Hg均未检出。辽宁市场上食用菌大部分是安全的。     

Attraction of female fungus gnats,Lycoriella ingenua,to mushroom‐growing substrates and the green mold Trichoderma aggressivum

To evaluate the attractiveness of several mushroom‐growing substrates to the female mushroom fly Lycoriella ingenua (Dufour) (Diptera: Sciaridae), a pest of the cultivated white button mushroom, Agaricus bisporus (JE Lange) Emil J Imbach (Agaricales), we developed a two‐choice, static‐flow olfactometer. Behavioral assays using this olfactometer indicated that mushroom compost with A. bisporus mycelia growing in it was not more attractive than compost lacking growing mycelia. We also found that female flies were more attracted to compost lacking A. bisporus mycelia than to the actual commodity, the white button mushroom fruiting bodies. Flies were not, however, attracted to sterilized compost, suggesting the attraction is due to volatiles produced by microbial metabolism in the compost. We also found that female L. ingenua flies were attracted to the mycoparasitic green mold Trichoderma aggressivum Samuels & W Gams (Hypocreales). Flies preferred mushroom compost that had T. aggressivum growing in it over compost lacking T. aggressivum, providing an experimental outcome consistent with the anecdotal belief that L. ingenua flies are vectors of T. aggressivum spores that can infest mushroom‐growing houses.     

3种不同来源侧耳品种亲缘关系差异化分析

采取拮抗实验、酯酶同工酶、基因组进行多态性分析(RAPD)、内部转录间隔区序列(ITS)对来源不同的特大凤尾菇(Pleurotus sajor-caju)、夏秀990(Pleurotus geesteranus)和黑平A3三个侧耳品种的亲缘关系进行了对比分析。实验结果表明:供试的3个侧耳品种从形态学水平、蛋白质水平和分子水平上看,其品种间亲缘关系界定具有一致性。表现为特大凤尾菇与夏秀990的亲缘关系较近,与黑平A3的亲缘关系较远,夏秀990与黑平A3亲缘关系较远。本研究从不同的水平,为食用菌菌种属间亲缘关系的鉴定提供了综合分析方法,对区分同种异名、杂交亲本选择以及判定杂交结果具有指导意义。     

Bacteria associated with the sponge Spongia officinalis as indicators of contamination

A lot of micro-organisms can been found in the sponge body. In the present study, bacteria and fungi were isolated from the massive commercial sponge Spongia officinalis Linnaeus, 1759 (Porifera, Demospongiae). Samples (sponge extract and sea water) were collected from several areas of the Aegean Sea (ports, beaches, eutrophic gulf and open sea) with different levels and types of contamination. Bacteria identified in sponge extract belong to the genera Escherichia, Morganella, Proteus, Pasteurella, Aeromonas, Pseudomonas and Acinetobacter. Two fungal genera, Trichosporum and Fisarium, were identified in sponge extract. Bacterial load was greater in sponge extract than in proximal sea water, reflecting the sponge ability to concentrate bacteria in its body. The assessment of bacteria associated with the sponge S. officinalis as indicators of contamination is proposed.     

Sponge–seaweed associations in species of Ptilophora (Gelidiaceae, Rhodophyta)

Sponge–seaweed associations in the seaweed genus Ptilophora are poorly understood; therefore, 94 specimens, representing all 17 species of Ptilophora, were examined to detail this phenomenon. All but 2 Ptilophora species were shown to produce surface proliferations, with 13 species found to have sponge associations. Evidence for facultative sponge epiphytism was found with species–specific interactions being unlikely. Results show that surface proliferations are not induced by sponge epiphytes, as they often occur in the absence of sponge epiphytes, and vice versa. The significant number of proliferate thalli found with sponge epiphytes suggests that there is a likely relationship between the presence of surface proliferations and sponge infestation. Sponge epiphytes and Ptilophora species appeared structurally related in that the sponge probably exploits a niche habitat provided by the alga, for which surface proliferations might aid the sponge in bonding to the alga.     

Invasive alga <Emphasis Type="Italic">Caulerpa racemosa</Emphasis> var. <Emphasis Type="Italic">cylindracea</Emphasis> makes a strong impact on the Mediterranean sponge <Emphasis Type="Italic">Sarcotragus spinosulus</Emphasis>

Here we present the first observation of the impact of the invasive Caulerpa racemosa var. cylindracea on native photophilic sponge species in the Adriatic Sea, with special focus on Sarcotragus spinosulus. Caulerpa racemosa var. cylindracea is able to completely overgrow the sponge, developing an exceptionally thick canopy with a maximum measured density of 1,887 m of stolons m⁻² and 40,561 fronds m⁻². Necrosis of the sponge surface was significantly correlated with the algal dry biomass, frond number and stolon length. Dense algal canopy, penetration of the algal stolon and rhizoids into the sponge oscula and covering of the ostiae probably diminishes the seawater circulation through the sponge and consequently results in its smothering and even death. We suggest that chemotropism is the reason why C. racemosa penetrates the sponge oscula and establishes such dense canopy on the sponge.     

Activity and distribution of the mushroom phorid fly,Megaselia halterata,in and around commercial mushroom farms

The mushroom phorid fly, Megaselia halterata (Wood) (Diptera: Phoridae), is a key pest in mushroom farming in most parts of the world. Studies on the mushroom phorid fly have focused on its life history within mushroom growing houses, but little is known about the fly's activity outside mushroom growing houses. In this study, daily activity and distribution of adult M. halterata in the areas surrounding mushroom growing houses was studied using yellow sticky traps. Results suggest that M. halterata focuses its flight activity over turf areas rather than windbreaks and spent compost piles, possibly for mating purposes. Our study found no evidence of M. halterata breeding in turf areas surrounding mushroom growing houses. In addition, flight activity is highest in the afternoon until midnight at higher temperatures, yet at lower temperatures activity ceases after sunset. Establishing temperature and daylight thresholds for M. halterata flight activity may be useful in developing integrated pest management (IPM) tactics for this species. The most successful IPM tool that mushroom growers use at present is fly exclusion. Exclusion can be improved by focusing farm operations around temperature and daylight thresholds when fly activity is at its lowest.     

Antibacterial Activity and Drug Release of Chitosan Sponge Containing Doxycycline Hyclate

The purpose of the present study was to develop and characterize the chitosan sponges loading with doxycycline hyclate and their antibacterial activities. The pore density of chitosan sponge prepared with freeze drying technique was increased as the higher concentrated chitosan solution was used. The sponge prepared from 10% w/w of the chitosan solution and crosslinking with glutaraldehyde solution was utilized for loading with doxycycline hyclate. The drug release and sustainable antibacterial activity of fabricated sponge were assessed using dissolution test and agar diffusion test, respectively. Drug release from non-crosslinked sponge into phosphate buffer pH7.4 was slower than that from crosslinked sponge since the former could absorb the medium and form gel to retard the initial drug diffusion. Sustainable antibacterial activity of developed sponge was evident against S. aureus and E. coli. In conclusion, the in vitro release profile and antibacterial efficiency indicated that doxycycline hyclate could be sustained using chitosan sponge.     

Compositional analysis of archaeal communities in high and low microbial abundance sponges in the Misool coral reef system,Indonesia

The high/low microbial abundance (HMA/LMA) dichotomy in sponges has been the subject of several studies over recent years, but few studies have analysed this dichotomy in terms of the sponge archaeal community and function. Using a 16S rRNA gene barcoded pyrosequencing approach and predictive functional analysis (PICRUSt) we compared the archaeal composition, richness and predicted function of one HMA sponge (Xestospongia testudinaria), one LMA sponge (Stylissa carteri) and one sponge species of unknown microbial abundance (Aaptos lobata). Although most of the archaeal sequences were assigned to the Crenarchaeota phylum, S. carteri had the highest percentage of sequences assigned to the Euryarchaeota phylum. Variation among sponge species explained >85% of the variation in archaeal operational taxonomic unit (OTU) composition with each sponge species forming a distinct cluster. There were significant differences in predicted PICRUSt profiles among sponge species, suggesting that archaeal communities present in the studied sponge species may perform different functions. X. testudinaria and A. lobata were similar both in terms of OTU and KEGG orthologues composition, which may indicate that A. lobata is a HMA sponge. Additionally, some of the most enriched functions seem to be related to traits associated with high and low microbial abundance sponges.     

A subpopulation of mushroom body intrinsic neurons is generated by protocerebral neuroblasts in the tobacco hornworm moth, Manduca sexta (Sphingidae, Lepidoptera)

Subpopulations of Kenyon cells, the intrinsic neurons of the insect mushroom bodies, are typically sequentially generated by dedicated neuroblasts that begin proliferating during embryogenesis. When present, Class III Kenyon cells are thought to be the first born population of neurons by virtue of the location of their cell somata, farthest from the position of the mushroom body neuroblasts. In the adult tobacco hornworm moth Manduca sexta, the axons of Class III Kenyon cells form a separate Y tract and dorsal and ventral lobelet; surprisingly, these distinctive structures are absent from the larval Manduca mushroom bodies. BrdU labeling and immunohistochemical staining reveal that Class III Kenyon cells are in fact born in the mid-larval through adult stages. The peripheral position of their cell bodies is due to their genesis from two previously undescribed protocerebral neuroblasts distinct from the mushroom body neuroblasts that generate the other Kenyon cell types. These findings challenge the notion that all Kenyon cells are produced solely by the mushroom body neuroblasts, and may explain why Class III Kenyon cells are found sporadically across the insects, suggesting that when present, they may arise through de novo recruitment of neuroblasts outside of the mushroom bodies. In addition, lifelong neurogenesis by both the Class III neuroblasts and the mushroom body neuroblasts was observed, raising the possibility that adult neurogenesis may play a role in mushroom body function in Manduca.     

How many neuroblasts build mushroom bodies in <Emphasis Type="Italic">Lucilia caesar</Emphasis> L. and <Emphasis Type="Italic">Musca domestica</Emphasis> L. (Diptera,Brachycera Cyclorrhapha)?

The green-bottle fly Lucilia caesar and the housefly Musca domestica differ greatly in the number of neuroblasts producing mushroom bodies. Four neuroblasts were found in each mushroom body of Lucilia pupae, and its calyx has a quadruple structure. In the housefly, the number of mushroom body neuroblasts rises up 20 in each brain hemisphere. This leads to a more complicated calyx structure. The neuroblast number observed in Lucilia and Musca is compared with that found in other Diptera.     

Mangrove-sponge associations: a possible role for tannins

A positive correlation between sponge coverage and tannin concentrations in prop roots of Rhizophora mangle L. has previously been reported. However, the ecological role of tannins within the mangrove sponge association remains speculative. This study investigated whether tannins play a role in sponge recruitment and assessed tannin and polyphenol production in R. mangle roots in response to sponge colonization. We demonstrated in a field experiment using artificial substrates with different tannin concentrations that tannins are positively involved in larval recruitment of the sponge Tedania ignis and that roots significantly enhanced tannin and polyphenolic content in response to natural and experimental sponge fouling. Differential recruitment in response to tannins may have been the result of a behavioral response in sponge larvae. It is also possible that tannins affected the structure of the fouling microbial biofilm on the artificial substrate, or tannins affected the post-settlement dynamics of sponge recruits. Elevations in concentrations of tannins and polyphenolic compounds upon coverage with sponges, combined with differential recruitment of T. ignis in response to differences in tannin concentrations, may indicate a positive feedback in recruitment. This may in part explain the typical heterogeneity in sponge coverage and community composition among roots.     

Trophodynamics of the sclerosponge Ceratoporella nicholsoni along a shallow to mesophotic depth gradient

The sclerosponge Ceratoporella nicholsoni is a hyper-calcifying high microbial abundance sponge. This sponge has been observed at high densities throughout the Caribbean in the mesophotic zone (30–150 m), as well as cryptic environments in shallow (< 30 m) depths. Given the densities of this sponge, it could play an important role in the cycling of inorganic and organic sources of carbon and nitrogen at mesophotic depths. Additionally, there is broad interest in this sponge as a tool for paleobiology, paleoclimatology and paleoceanography. As a result, it is increasingly important to understand the ecology of these unique sponges in the underexplored Caribbean mesophotic zone. Here we show that this sponge increases in abundance from shallow depths into the mesophotic zone of Grand Cayman Island. We observed no significant differences in the stable isotope signatures of δ¹⁵N and δ¹³C of sponge tissue between depths. A predictive model of sponge diet with increasing depth shows that these sponges consume dissolved organic matter of algal and coral origin, as well as the consumption of particulate organic matter consistent with the interpretation of the stable isotope data. The taxonomic composition of the sclerosponge microbiome was invariant across the shallow to mesophotic depth range but did contain the Phylum Chloroflexi, known to degrade a variety of dissolved organic carbon sources. These data suggest that the depth distribution of this sponge may not be driven by changes in trophic strategy and is potentially regulated by other biotic or abiotic factors.

     

Introductory comments

Abstract

Associated microorganisms have been described in numerous marine sponges. Their metabolic activity, however, has not yet been investigated in situ. We quantified for the first time microbial processes in a living sponge. Sulfate reduction rates of up to 1200 nmol cm^?3d^?1 were measured in the cold-water bacteriosponge Geodia barretti . Oxygen profiles and chemical analysis of sponge tissue and canal water revealed steep oxygen gradients and a rapid turnover of oxygen and sulfide, dependent on the pumping activity of the sponge. Identification of the microbial community with fluorescently labelled oligonucleotide probes (FISH) indicates the presence of sulfate-reducing bacteria belonging to the Desulfoarculus/Desulfomonile/Syntrophus -cluster in the choanosome of this sponge. Analysis of lipid biomarkers indicates biomass transfer from associated sulfate-reducing bacteria or other anaerobic microbes to sponge cells. These results show the presence of an anoxic micro-ecosystem in the sponge G. barretti, and imply mutualistic interactions between sponge cells and anaerobic microbes. Understanding the importance of anaerobic processes within the sponge/microbe system may help to answer unsolved questions in sponge ecology and biotechnology.     

Effect of lignin-derived phenolic monomers on the growth of the edible mushrooms Lentinus edodes,Pleurotus sajor-caju and Volvariella volvacea

Pleurotus sajor-caju was generally more tolerant to lignin-related phenolic monomers and tannin derivatives than Lentinus edodes and the straw mushroom, Volvariella volvacea. Several phenols, at up to 5 mM, enhanced mycelial growth of P. sajor-caju. No clear pattern was evident when the effects of phenols and tannins on the growth of V. volvacea and L. edodes were compared, but the lower concentrations of 4-hydroxybenzaldehyde and vanillin which were tested were markedly more toxic to the straw mushroom. The distribution of phenolic monomers and tannin derivatives in the agricultural wastes used for mushroom cultivation may be an important growth determinant. However, the differences in the growth inhibition profiles of L. edodes, P. sajor-caju and V. volvacea suggest that, alone, the effect of these compounds on fungal growth is unlikely to account for the varying abilities of the three mushroom species to grow and fruit on a particular lignocellulosic substrate.     

A Study of Cultural Bias in Field Guide Determinations of Mushroom Edibility Using the Iconic Mushroom, Amanita muscaria, as an Example

A Study of Cultural Bias in Field Guide Determinations of Mushroom Edibility Using the Iconic Mushroom, Amanita muscaria , as an Example. Mushroom field guides teach identification skills as well as provide information on the edible or toxic qualities of each species of wild mushroom. As such they function as modern-day village elders for an increasingly urban, nature-ignorant population. This paper identifies underlying cultural bias in the determination of mushroom edibility in English-language field guides, using the iconic mushroom, Amanita muscaria, as an example. We explore a selection of ethnographic and medical texts that report the use of A. muscaria as a food, and we accept parboiling as a safe method of detoxifying it for the dinner table. Mushroom field guides, however, almost universally label the mushroom as poisonous. We discuss the cultural underpinnings and literary form of mushroom field guides and demonstrate that they work within a mostly closed intellectual system that ironically shares many of the same limitations of cultural bias found in traditional folk cultures, but with the pretense of being modern and scientific. An erratum to this article can be found at     

16S rDNA clone library-based bacterial phylogenetic diversity associated with three South China Sea sponges

Culture-independent molecular techniques, 16S rDNA clone library alongside RFLP and phylogenetic analysis, were applied to investigate the bacterial diversity associated with three South China Sea sponges, Stelletta tenui, Halichondria rugosa and Dysidea avara. A wide bacterial diversity was detected according to total genomic DNA-based 16S rDNA clone library, abundant clones with low identify with sequences retrieved from database were found as well as uncultured sponge symbionts. The phylogenetic analysis shows that the bacterial community structure of Stelletta tenui is similar to that of Halichondria rugosa comprising gamma-Proteobacteria and Firmicutes. Whereas, alpha-Proteobacteria, gamma-Protebacteria, Bacteroidetes and uncultured sponge symbionts were found in sponge Dysidea avara, suggesting that Dysidea avara has the highest bacteria diversity among these sponges. A specific sponge–microbe association is suggested based on the difference of bacterial diversity among these three sponges from the same geography location and the observed sponge species-specific bacteria.     

Factors affecting entomophilic activity of Neoaplectana feltiae in mushroom compost

The host-searching ability of Neoaplectana feltiae Filipjev (= S. bibionis Bovien) (Nematoda: Steinernematidae) in response to larvae of a mushroom fly, Lycoriella solani Winn. was examined in a mushroom substrate. Individuals of L. solani were less attractive for the parasite than larvae of Galleria mellonella L. The nematode juveniles penetrated a 22 cm layer of casing mixture within 2–4 days. In the casing alone nematode effectiveness was better than in mushroom compost or in compost and casing together. In the casing mixture parasite dosages of 20 and 100 juveniles per cm² led to 22% and 45% parasitization of L. solani respectively, while all G. mellonella larvae were parasitized at both dosages. The prevalence of nematode infection depended on the content of water in the mushroom substrate. The highest N. feltiae infectivity was observed, when the ratio of the dry casing weight to the weight of water content was 1: 2.5. The practical aspects of the observed phenomena, essential for the use of N. feltiae in the protection of commercial mushroom cultivation are discussed.     

The oldest labechiid stromatoporoids from intraskeletal crypts in lithistid sponge–Calathium reefs

Early Ordovician (early Floian) reefs of South China include lithistid sponge–Calathium reefs with a three‐dimensional skeletal framework. These structures are among the first post‐Cambrian skeletal‐dominated reef structures and provides an opportunity to test how the novel metazoan builders changed the environments and increased topographic complexity within benthic communities. We document the oldest labechiid stromatoporoid (Cystostroma) in a lithistid sponge–Calathium reef of the Hunghuayuan Formation in southeastern Guizhou, South China. These earliest stromatoporoids may have originated in reefs, and we argue that the complex topography created by the hypercalcified sponge Calathium facilitated the emergence of stromatoporoids. Beyond Cystostroma, keratose sponges, Pulchrilamina (hypercalcified sponge) and bryozoans have also inhabited in the micro‐habitats (cavities and hard substrates) provided by Calathium. These findings suggest that ecosystem engineering by Calathium played an important role in the further diversification of reefs during the Ordovician.