Mycelium Powder Research Articles

Enzymatic System of Antioxidant Protection of Erythrocytes in Diabetic Rats Treated with Medicinal Mushrooms Agaricus brasiliensis and Ganoderma lucidum (Agaricomycetes).

Excessive glucose concentrations in blood and cells promote the intensification of auto-oxidation. This is one of the mechanisms through which free radicals form in hyperglycemia. As a result of hyperglycemia, oxidative stress develops and lipid peroxidation (LPO) is enhanced. Erythrocytes are particularly susceptible to reactive oxygen species and LPO, which can violate cell functions. This article describes the analysis of the influence of mycelia from the medicinal mushrooms Agaricus brasiliensis and Ganoderma lucidum on the enzymatic link of the antioxidant system in rat erythrocytes under streptozotocin-induced diabetes mellitus. Oxidative stress was strengthened in red blood cells of diabetic rats, as evidenced by decreased activity of antioxidant enzymes such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase, and by increased amounts of thiobarbituric acid-positive products, which are markers of LPO. Administration of A. brasiliensis and G. lucidum submerged cultivated mycelial powder to animals with streptozotocin-induced diabetes restored superoxide dismutase, catalase, and glutathione peroxidase activity and reduced the amounts of thiobarbituric acid-positive products to control values, but did not affect the activity of glutathione reductase.

Agaricus subrufescens: substratum nitrogen concentration and mycelial extraction method on antitumor activity

Antitumor activity of Agaricus subrufescens has been shown on vegetative mycelium and basidiocarp. However, few studies have assessed the effect of A. subrufescens cultivation conditions and extraction methods on antitumor activity. This study evaluated the effect of nitrogen concentration on the cultivation medium of A. subrufescens and the extraction method of mycelial antineoplastic actives against sarcoma 180 cells implanted in mice. Two nitrogen sources (isolated soybean protein and NaNO3) and 10 nitrogen concentrations (0.25 to 8.0 g/L) were used. Dried mycelium extract was obtained by hot water infusion (1:10 mass:volume; 90 °C) or by aqueous mixture (1:10 mass:volume, ambient temperature) in ultrapure water. The doses were administered daily by gavage to mice implanted with sarcoma 180 cells. Isolated soy protein is more efficient to mycelial biomass production than NaNO3. The mycelial biomass production increases when the cultivation medium is added with high nitrogen concentrations as well as the splenic index and the antitumor activity of the moistened mycelial powder. Hot water extract is more effective than the moistened mycelial powder to reduce tumor. The antitumor activity of hot water mycelial extract is similar to the one of basidiocarps, presenting lower metabolic demand on the spleen, keeping blood parameters normal and promoting animal wellness.

Production of N-Acetyl-d-glucosamine from Mycelial Waste by a Combination of Bacterial Chitinases and an Insect N-Acetyl-d-glucosaminidase.

N-Acetyl-d-glucosamine (GlcNAc) has great potential to be used as a food additive and medicine. The enzymatic degradation of chitin-containing biomass for producing GlcNAc is an eco-friendly approach but suffers from a high cost. The economical efficiency can be improved by both optimizing the member and ratio of the chitinolytic enzymes and using new inexpensive substrates. To address this, a novel combination of bacterial and insect chitinolytic enzymes was developed in this study to efficiently produce GlcNAc from the mycelia of Asperillus niger, a fermentation waste. This enzyme combination contained three bacterial chitinases (chitinase A from Serratia marcescens (SmChiA), SmChiB, SmChiC) and one insect N-acetyl-d-glucosaminidase from Ostrinia furnacalis (OfHex1) in a ratio of 39.1% of SmChiA, 26.7% of SmChiB, 32.9% of SmChiC, and 1.3% of OfHex1. A yield of 6.3 mM (1.4 mg/mL) GlcNAc with a purity of 95% can be obtained from 10 mg/mL mycelial powder in 24 h. The enzyme combination reported here exhibited 5.8-fold higher hydrolytic activity over the commercial chitinase preparation derived from Streptomyces griseus.

Advances in Clinical Toxicology ISSN: 2577-4328 Genotoxicity, Acute and Sub-Chronic Toxicity Studies of Solid-State Cultivated Mycelial Powder of Antrodia Cinnamomea Adv Clin Toxicol Genotoxicity, Acute and Sub-Chronic Toxicity Studies of Solid-State Cultivated Mycelial Powder of Antrodia cinnamomea

Antrodia cinnamomea is a precious medicinal mushroom endemic to Taiwan that has been used as folk medicine for health promotion and treating various diseases. In this study, the toxicological assessment of solid-state cultivated mycelial powder of A. cinnamomea (LE-SC) was performed using in vitro and in vivo assays. The maximum tolerated dose (MTD) of LE-SC was determined to be greater than 13.3 g/kg bw. In addition, LE-SC showed no mutagenicity in Ames test and no genotoxic activity up to the dose of 10 g/kg bw in mammalian erythrocyte micronucleus and mice sperm abnormality tests. Moreover, result from 90 days repeated dose toxicity test showed that administration of LE-SC (1.9, 3.8 and 7.6 g/kg bw) in the diet had no observable adverse effects in both male and female rats. Accordingly, the results ensured the safety of LE-SC as food supplement and for human consumption.

Effect of Medicinal Mushrooms on L-arginine/NO System in Red Blood Cells of Streptozotocin-induced Diabetic Rats

Increase of nitric oxide production resulted in the development of oxidative-nitrosative stress that is considered to be an etiological cause of many diseases, including diabetes mellitus (DM). Recently, it was found that red blood cells (RBCs) are able to produce nitric oxide (NO), and due to the ability of hemoglobin to bind to nitric oxide, are the main depot of NO. Medicinal mushrooms are widely used in the correction and treatment of many diseases, including diabetes. Our previous results showed that Agaricus brasiliensis and Ganoderma lucidum have hypoglycemic effects and improve the functional state of RBCs. In this study, the influence of submerged cultivated mycelium powder (SCMP) of the abovementioned mushrooms on the red blood cells L-arginine/NO system of streptozotocin-induced DM rats was investigated. Wistar outbread white rats were used in the study. Streptozotocin was intraperitoneal injected one time at a dose of 50 mg/kg body weight. Mushroom preparations were orally administered at a dose of 1 g/kg/day for 14 days. We showed that administration of medicinal mushrooms SCMP to diabetic animals caused restoration of NO-synthase activity, normalized nitrite content (in case of A. brasiliensis), and led to nitrate growth. Therefore, treatment with mushroom mycelia normalizes the production of nitric oxide to physiological values.

Purification, structural characterization and in vitro antioxidant activity of a novel polysaccharide from Boshuzhi

A novel polysaccharide, designated GCPB-1b, was obtained from the alkaline extract of the submerged fermentation culturing mycelium powder of Boshuzhi, Ganoderma capense. This polysaccharide was purified by ion-exchange and gel-permeation column chromatography and is a glucan (MW 2847Da). GCPB-1b has a specific optical rotation of [α]D25=+154° (c 1.0, H2O). Based on monosaccharide analysis, partial acid hydrolysis, periodic acid oxidation-Smith degradation, methylation analysis, Fourier transform-infrared spectroscopy (FT-IR), gas chromatography-mass spectrometry (GC–MS) and nuclear magnetic resonance (NMR) spectroscopy, the backbone of GCPB-1b was composed of (1→4)-linked-α-d-glucose residues and (1→4,6)-linked-α-d-glucose residues. Furthermore, GCPB-1b had 1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging ability (EC50 3.23μM) according to antioxidant activity tests which was greater than other antioxidants. These data suggest that GCPB-1b holds promise as an anti-aging functional food.

Effection of Anti-fatigue of Selenium-rich Cordyceps Militaris in Mice

Purpose to probe into the anti-fatigue ability of selenium-rich Cordyceps militaris. Research methods: (1) Determination of mycelium components: The polysaccharides, organic selenium and superoxide dismutase of mycelium were measured; (2) Determination of anti-fatigue ability: The mice were treated with different dosages of selenium-rich mycelium per day. Each group was tested separately of the mice’s exhaustive swimming time and the content of blood lactate and blood urea nitrogen. Results: the content of mycelia polysaccharide and the activity of superoxide dismutase (SOD) in Cordyceps militaris enriched selenium mycelia was increased. The mice treated with mid-dosage obviously prolonged the weight loading swimming exhaustive time. The mid-dosage of selenium-rich Cordyceps militaris could prolong or reduce the production of lactate acid, quicken the clearance of lactate acid. Conclusions: The polysaccharides content, organic selenium content and the activity of SOD enzyme in the selenium-rich mycelium powder increased significantly. selenium-rich Cordyceps militaris can increase the anti-fatigue ability of the exercise in the mice.

The Effect of the Medicinal Mushrooms Agaricus brasiliensis and Ganoderma lucidum (Higher Basidiomycetes) on the Erythron System in Normal and Streptozotocin-Induced Diabetic Rats.

Diabetes mellitus (DM) is accompanied by the development of hypoxia, which disturbs the physicochemical properties of the erythrocyte membrane and further leads to the occurrence of anemia and a reduction of the lifespan. In response, the body activates compensatory reactions directed at a renewal of the red blood cell pool and an increase in tissue oxygenation. In this study the influence of Agaricus brasiliensis and Ganoderma lucidum medicinal mushroom mycelia on the erythron system of control and streptozotocin (STZ)-induced diabetic rats were investigated. Wistar outbred white male rats were intraperitoneally injected with saline (control rats) or STZ (50 mg/kg, DM rats) and orally treated with placebo or submerged culture mycelium powder (1 g/kg/day) for 2 weeks. Peripheral blood erythrocytes were collected. Hypoglycemic effects of A. brasiliensis and G. lucidum occurred in the diabetic rats, as evidenced by decreased blood glucose and glycosylated hemoglobin concentrations. In STZ-diabetic animals treated with submerged culture mycelium powder, an increase in the number of erythrocytes in the bloodstream (an antianemic effect), erythrocyte resistance to acid hemolysis, and the normalization of fetal hemoglobin concentrations, along with the intensification of erythropoiesis were observed. In conclusion, our results suggest that in diabetic animals A. brasiliensis and G. lucidum have therapeutic effects that manifest in hypoglycemic and antianemic action.

Structural Changes of Erythrocyte Surface Glycoconjugates after Treatment with Medicinal Mushrooms.

Under conditions of chronic hyperglycemia there is dysregulation of ion homeostasis, violation of redox metabolism and functioning of membrane enzymes, as well as changes in the structural and functional states of erythrocyte membranes. As a result, the aggregation ability of erythrocytes increased and their deformability decreased. These changes lead to complications to microcirculation blood flow and provoke the development of vascular complications caused by diabetes mellitus. This study investigated the effect of the medicinal mushrooms Agaricus brasiliensis and Ganoderma lucidum on the structure of carbohydrate determinants of surface membrane glycoconjugates of rat peripheral blood erythrocytes under both normal conditions and streptozotocin-induced diabetes mellitus. The research was carried out using Wistar outbred white rats. Diabetes was induced by streptozotocin intraperitoneally injected once at a dose of 50 mg/kg body weight. The mushroom preparations were orally administered at a dose of 1 g/kg for 14 days. The treatment of diabetic rats by submerged culture mycelium powder restored the physiological balance between sialylation and desialylation processes, renewed the membrane surface charge of red blood cells, normalized aggregation properties, and caused the structural recovery of oligosaccharide chains of erythrocyte membrane surface glycoconjugates. The discovered changes show an improvement in the erythrocyte functional state and rejuvenation of their population caused by biologically active compounds of the studied medicinal mushrooms.

Multiple resistance-activating substances produced by Humicola phialophoroides isolated from soil for control of Phytophthora blight of pepper.

BackgroundMicroorganisms capable of utilizing vegetable tissues for multiplication in soil were isolated, cultivated in liquid medium prepared from the same vegetable tissues, and tested for ability to activate resistance in pepper leaves against Phytophthora blight caused by Phytophthora capsici.ResultsAmong the 121 microorganisms isolated, a fungus Humicola phialophoroides showed distinct ability to produce substances capable of activating resistance. The resistance-activating substances produced by H. phialophoroides were mostly retained in the mycelium, and were readily extracted from the mycelium powder with polar solvents. The extract was not inhibitory to zoospore germination or germ tube growth of P. capsici. In pepper leaves, the extract took only about 12 h to activate resistance against P. capsici. After activation, washing treated leaf surface with water did not have much effect on the resistance expression. In addition to being able to move from the upper leaf surface to lower leaf surface, the resistance-activating substances were capable of moving 5 mm acropetally and 10 mm basipetally in pepper leaves, Chromatography of the extract on silica gel column suggests that there are probably more than three components in the extract with resistance-activating ability. The resistance-activating activity of the mycelium extract was not affected by treatment with either cation or anion exchange resins, indicating that none of the active components have positive or negative charges on their molecules.ConclusionResults show that H. phialophoroides is capable of producing multiple resistance-activating substances which are mostly retained in the mycelium. The study also indicates that none of the active components have positive or negative charges on their molecules.Electronic supplementary materialThe online version of this article (doi:10.1186/1999-3110-55-40) contains supplementary material, which is available to authorized users.

Mycelial antineoplastic activity of Agaricus blazei.

Basidiocarp of Agaricus blazei (=Agaricus brasiliensis; =Agaricus subrufescens) is used as teas or capsules due to its antineoplastic effect but there are few reports of using mycelium for this purpose. The objective of this study was to evaluate the antineoplastic activity on sarcoma 180 cells implanted in mice of two forms of preparation of the mycelium from two A. blazei strains grown in culture medium with different concentrations of isolated soy protein. Mycelia were grown in Pontecorvo medium with different concentrations of isolated soybean protein (ISP). Mycelial hot water extract, moistened mycelial powder, hot water extract of green tea, Ifosfamida(®) (ifosfamide drug), and saline solution were administered daily by gavage in mice with sarcoma 180 cells to evaluate antineoplastic activity. It was concluded that antineoplastic activity was the same for both strains, except when used as moistened mycelial powder, which rules out the use of mycelial powder in capsules. Mycelial hot water extract had high antineoplastic activity with lower metabolic demand on the spleen and maintenance of normal blood parameters. Mycelial growth in different ISP concentrations had the same antineoplastic activity. Also the vegetative mycelium was as effective as the basidiocarp for sarcoma 180 tumor inhibition. Green tea was as effective as mycelial hot water extract.

Rapid Discrimination of Fermented Cordyceps Mycelium Powder by Near-Infrared Spectroscopy (NIRS)

The potential of near-infrared spectroscopy (NIRS) was investigated for its ability to rapidly discriminate the various brands of fermented Cordyceps mycelium powder. Relationship between mycelium powder varieties and the absorbance spectra was well established with the spectra region of 12500-4000 cm-1. Spectra preprocessing was performed using 1st derivative. Principal component analysis (PCA) was adopted for the clustering analysis and re-expressing of the hyper spectral data, and then, the obtained principal components (PCs) were used as the input of back-propagation artificial neural network (BPANN) to build PCA-BPANN model for the variety discrimination. The unknown samples in prediction set were precisely identified with the correlation coefficient R of 0.9959 and root-mean-square error of prediction (RMSEP) of 0.1007, which suggests that the NIR spectroscopy, if coupled with appropriate pattern recognition method, is very promising for rapid and nondestructive discrimination of fermented Cordyceps mycelium powder.

Extension of Life Span and Improvement of Vitality in Drosophila melanogaster by Supplementation with Lycopene Mycelium Powder from Blakeslea trispora

Extension of Life Span and Improvement of Vitality in Drosophila melanogaster by Supplementation with Lycopene Mycelium Powder from Blakeslea trispora

Isolation and Purification of Polysaccharides with Anti-tumor Activity from Pholiota adiposa (Batsch) P. Kumm. (Higher Basidiomycetes)

Pholiota adiposa is a mushroom with excellent medicinal and nutritional properties. After culture in fermentation medium, Ph. Adiposa mycelia were filtered, lyophilized, and powdered. A crude polysaccharide (PAP) of Ph. Adiposa was prepared from the mycelial powder with hot water, centrifuged, and the resulting supernatant lyophilized. PAP was fractionated by 30%, 60%, and 80% ethanol precipitation steps to yield PAP30, PAP60, and PAP80. Subsequently PAP30-1 and PAP30-2, PAP60-1 and PAP60-2, and PAP80-1 and PAP80-2 were isolated from PAP30, PAP60, and PAP80, respectively, by ion-exchange chromatography on a DEAE-Sepharose column. Polysaccharide content increased from 43.8% in PAP to 50.54%~73.19% in PAP30-1~PAP80-2. The protein content was 4.92% at minimum in these polysaccharide products. In order to identify the chemical composition, the six polysaccharides (PAP30-1, PAP30-2, PAP60-1, PAP60-2, PAP80-1, and PAP80-2) were further purified by gel filtration on Sephacryl S-100-500. Finally, three water-soluble polysaccharides (PAP30-2a, PAP60-2b, and PAP80-2a) were obtained. HPLC analysis revealed that PAP30-2a, PAP60-2b, and PAP80-2a exhibited a molecular weight of 6.6 × 105 Da, 8.4 × 103 Da, and 3.5 × 103 Da, respectively. The glucose content in PAP80-2a, PAP60-2b, and PAP30-2a was 57.8%, 72.7%, and 68.9%, respectively. PAP30-2a, PAP60-2b, and PAP80-2a demonstrated significant differences in anti-tumor activity in mice. PAP80-2a is the optimal bioactive constituent with anti-tumor and T-lymphocyte proliferation stimulating effects.

DNA isolation and optimization of sequence-related amplified polymorphism-polymerase chain reaction (SRAP-PCR) condition for endangered Polyporus umbellatus

To provide a fast genetic diversity survey of endangered Polyporus umbellatus (Pers.) Fries for immediate conservation, DNA isolation and optimization of polymerase chain reaction (PCR) assay of sequence-related amplified polymorphism (SRAP) were investigated. Due to high amount of polysaccharide contained in mycelium, three special approaches were adopted to eliminate it during DNA isolation, including adding RNAiso-mate for plant tissue buffer to mycelium powder, ethanol to DNA extraction buffer and 5% NaCl solution to the mixture of isoamyl alcohol and DNA deposit solution. Based on screening design, the optimal SRAP-PCR condition was a total volume of 25 μl containing 20 ng of DNA template, forward primer 0.4 μM, reverse primer 0.4 μM, 1× Taq MasterMix and the best annealing temperature was 35/50°C for each primer combination. According to our optimal SRAP-PCR condition, forty-nine out of eighty-one primer combinations were chosen for their high clarity and repetition in all samples. Key words: DNA isolation, sequence-related amplified polymorphism (SRAP), optimal polymerase chain reaction (PCR) condition, Chuling, Polyporus umbellatus.

Effects of Astragalus polysaccharides and Cordyceps sinensis mycelium mixture on the transforming growth factor-beta1 expression in chronic rejection of artery transplantation: experiment with rats

To explore the effect of Astragalus polysaccharides (APS) and Cordyceps sinensis (CP) mycelium mixture on the chronic rejection of artery transplantation. The abdominal arteries of 180 Wistar rats were isolated and transplanted to 180 SD rats whose with their abdominal arteries resected. The 180 recipient SD rats were randomly divided into blank control group (n = 20), APS group (n = 40, receiving gastric perfusion of APS 1 mg/kg bid), APS + low-dose CP group (n = 40, receiving APS and CP mycelium powder 1.25 g/d), APS + medium-dose CP group (n = 40, receiving APS and CP mycelium powder 2.5 g/d), and APS + high-dose CP group (n = 40, receiving APS and CP mycelium powder 5 g/d). Thirty days later the SD rats were killed with the transplanted abdominal arteries taken out to undergo microscopy. The expression of transforming growth factor (TGF)-beta(1) in the transplanted artery was examined by immunohistochemistry. In the control group, overexpression of TGF-beta(1) was observed in the intimal smooth muscle cells, monocytes, arterial endothelial cells, and arteriole, venule, and blood capillary endothelial cells in extima. However, the expression levels of TGF-beta(1) in the APS group and the 3 mixture administration groups were all significantly lower, especially in the medium- and high-dose groups (all P < 0.01). Severe edema of arterial endothelial cells and proliferation of monocytes were observed microscopically in the control group. Under electron microscope, rough endoplasmic reticulum and Golgi body were abundant in the control group. While in the mixture administration groups these changes were either weakened or absent. Astragalus polysaccharides and Cordyceps sinensis mycelium polysaccharides mixture can decrease the expression of TGF-beta(1) and inhibit the synthesis of collagen in the transplanted arteries.

Antidiabetic and hypolipidemic effects ofCollybia confluens mycelia produced by submerged culture in streptozotocin-diabetic rats

This investigation was undertaken to study the effects of oral administration (3 weeks) of Collybia confluens mycelial powder (CCMP) produced by a submerged culture on plasma glucose and other biochemical parameters in streptozotocin (STZ)-induced diabetic rats. Antidiabetic and hypolipidemic effects were proportionally increased with the increasing concentration of the CCMP for oral administration. The CCMP, at the dose of 400 mg/kg BW, substantially reduced the plasma glucose level by as much as 33.1% as compared to the STZ-induced diabetic rats group. It also lowered the plasma total cholesterol, triglyceride, and low density lipoprotein (LDL) cholesterol by 22.9%, 19.9%, and 37.3%, respectively. The levels of total cholesterol and triglyceride in liver were reduced to the extent of by 13.5% and 18.8%, and the activity of alanine transaminase (ALT) and aspartate transaminase (AST) was decreased by 48.8% and 37.2%, respectively, under the influence of CCMP. The general components of CCMP were found to contain 26.18% carbohydrate, 3.67% crude ash, 4.02% crude fat, 22.55% crude protein, and 43.58% dietary fiber. The amino acid composition of the CCMP was also analyzed in detail.

Effects of Zn supplementation on the growth, amino acid composition, polysaccharide yields and anti-tumour activity of Agaricus brasiliensis

The effects of Zn supplementation on the growth, amino acid composition, polysaccharide yields and anti-tumour activity of Agaricus brasiliensis were studied. An initial Zn concentration within the range of 0–300 mg/l had a significant effect on the cell growth and Zn biosorption. At an initial Zn concentration of 300 mg/l, a maximal extracellular polysaccharide (EPS) yield of 5.08 ± 0.25 g/l was obtained, as well as a maximal intracellular polysaccharide (IPS) of 12.25 ± 0.31 mg/g DW. Amino acid analysis results showed that the total amino acid contents of mycelia and culture filtrate decreased from 1090.08 ± 0.76 (233.62 ± 0.06) to 1077.40 ± 0.77 mg/100 g DW (229.52 ± 0.05 mg/l), respectively, while the total essential amino acid contents of mycelia and culture filtrate markedly increased from 429.51 ± 0.86 (58.84 ± 0.05) to 476.9 ± 0.85 mg/100 g DW (59.99 ± 0.04 mg/l), respectively. The anti-tumour activity of Zn-enriched mycelial powder against sarcoma 180 in mice showed that the tumour inhibition ratio was 61.5% and was enhanced markedly as compared to normal mycelial powder of 30.8. The fundamental information obtained in this study will be useful for efficient production of Zn-enriched foods or drugs.

The influence of lentinus edodes (shiitake mushroom) preparations on bacteriological and morphological aspects of the small intestine in piglets1

Among substances intended to replace growth promoting antibiotics in pig nutrition, non-digestible oligosaccharides or polysaccharides could be potential alternative compounds. Therefore, the influence of β-1,3-1,6 glucans on bacteriological, biochemical and morphological aspects of the small intestine in weaned piglets was investigated. As sources of β-glucans, Lentinan (extract of Lentinus edodes mycelium) or dried L. edodes mycelium were added to the diet. Four homogenous groups of 5 newly weaned piglets (4 weeks of age) received one of four diets: control diet (C), C supplemented with Avilamycin (50 mg/kg, positive control), C supplemented with 0.1% of Lentinan and C supplemented with 5% of dried L. edodes mycelium powder. A first group of 10 piglets was euthanized after 11 days and the remaining 10 on day 12 of the experiment. The gastrointestinal tract was divided in segments and samples taken from digesta (stomach, proximal and distal jejunum, caecum), mucosal scrapings (jejunum) and ring shaped tissue samples (1 cm) of proximal and distal jejunum. Bacterial counts were made with digesta and mucosal samples, and short-chain fatty acids (SCFA), lactic acid and ammonia concentrations were determined. Tissue samples of both jejunal sites were embedded in paraffin wax for morphometrical (villus length, crypt depth) and histological observations (numbers of intraepithelial lymphocytes (IEL), goblet cells, apoptotic enterocytes on villi, mitotic cells in crypts). Only the diet containing 5% of dried L. edodes consistently resulted in lower viable counts (ca. 1 – 2 log10 CFU) of total bacteria, E. coli, streptococci and lactic acid bacteria, and luminal and mucosal effects agreed very well. With this diet, acetate and butyrate concentrations in the distal jejunum were doubled, which is favourable in view of the trophic effect on enterocytes and colonocytes. Villus length (V) was increased with both diets containing β-glucans while crypt depth (C) was not altered, but V/C was higher. IEL counts were decreased by both diets although bacterial numbers, which is only one parameter of bacterial load, were only diminished with the L. edodes feed. The three supplemented feeds lowered the number of apoptotic enterocytes on the villi, but these numbers were very low (control diet : 44 cells per 100 villi), making clear interpretation difficult. The mitotic index was slightly lower with the L. edodes feed, although not statistically significant. Decreased viable counts observed with the latter diet is a favourable effect as it is accepted that a lower bacterial load causes lower turnover rates of the intestinal epithelial cells, while there is also less competition for specific substrates. A higher V/C ratio, a smaller number of IEL in the epithelium and a lower apoptotic index also indicate slower turnover rate of the mucosa when Lentinan and L. edodes diets were fed. The inconsistent effects observed with Lentinan were probably due to the low amount added to the diet. It should be taken into account that the influence of L. edodes mycelium powder was more likely due to the presence of antibacterial compounds (eg. lenthionine, lentinamycin, terpenoids, polyphenols), rather than to an immunostimulating action of β-glucans with increased release of IgA onto the mucosa surface.

Screening of field performance of entomopathogenic fungi and nematodes against cabbage root flies (Delia radicum l. and d. floralis (fall.); Diptera, Anthomyiidae)

Finnish isolates of Beauveria bassiana (8 isolates), Metarhizium anisopliae (7), Tolypocladium sp. (2), Paecilomyces farinosus (2), P. fumosoroseus (1), Steinernema feltiae (3) and Bacillus thuringiensis ('Muscabac') were tested for efficacy against mixed populations of Delia radicum and D. floralis under field conditions in 1986–90. All pathogens were applied preventatively, the fungi as aqueous conidial or mycelial suspensions, dry conidia or dry mycelial powder. In only two of the nine experiments did B. bassiana or M. anisopliae give some control. In 1986, B. bassiana SF85–2 and Tolypocladium sp. SF85–4 (both at rate 1.2 x 109 conidia plant‐ 1), and ‘Muscabac’ (25 g 1−1, 1 dl plant−1) reduced the number of pupae by 80%, 60% and 50%, respectively, as compared with untreated and chemical (isophenphos) controls. In 1990, M. anisopliae SF86–39 at rate 1.6 x 109conidia plant−1 and 1.5 x 108 CFU plant−1 and S. feltiae SFS‐22 (35000 plant−1), increased the yield of cauliflower 2.2, 1.8, and 2.3‐fold, respectively, as compared with the untreated control, but these yields were only 19%, 15% and 19% of those of the chemical (diazinon) control. Paecilomyces isolates were ineffective in the 1986 experiment in which they were included. Our results suggest that it is difficult to find efficient control agents among the fungal and nematode species tested for use as biopesticides against cabbage root flies, but that the potential of M. anisopliae against these pests deserves further study.