Production of chitinolytic enzymes with Trichoderma longibrachiatum IMI 92027 in solid substrate fermentation

Thirty Trichoderma strains representing 15 species within the genus have been screened for extracellular production of chitinolytic enzymes in solid substrate fermentation (SSF). T.longibrachiatum IMI 92027 (=ATCC 36838) gave the highest yield (5.0 IU/g dry matter of substrate) after 3 days of fermentation on wheat bran-crude chitin (9:1 mixture) medium. The optimum moisture content (66.7%), chitin content (20%), initial pH of the medium (2-5) and time course (5 d) of SSF were determined for strain IMI 92027. No significant effect of different N and P additives was found on the chitinase yield in wheat bran-chitin mixture medium. Cellulase, xylanase, alpha-amylase and beta-xylosidase activities were also detected. The pH and temperature optima of chitinase complex of T.longibrachiatum IMI 92027 was found to be at 4.5 and 55 ℃, respectively. The enzyme totally lost its activity at 70 ℃ in 5 min in the absence of the substrate but retained about 15% of its initial activity even at 70 ℃ after incubation of 60 min in the presence of SSF solids (residual substrate and fungal mycelium). Purification of protein extract from the SSF material revealed high chitinolytic activities between pI 5.9.-4.8 where N-acetyl-β-D-hexosaminidase and chitinase peaks have been found in the same pI range. Chitinase peaks could be described at least at four pI values: pI 5.9; 5.6; 5.3 and 4.8 while at least four main N-acetyl-β-D-hexosaminidase peaks could be separated at pI 6.0 and 5.1 and at more basic isoelectric points of 7.2 and 8.0. Two chitinases with 43.5 kDa and 30 kDa were purified at acidic isoelectric point.

Effect of Cultivar, Irrigation and Nitrogen Fertilization on Chickpea (<i>Cicer arietinum</i>L.) Productivity

A 2-year field study was conducted in northern Greece to investigate the effect of nitrogen fertilization and irrigation on productivity of three Greek chickpea varieties (“Amorgos” “Serifos”, “Andros”). Chickpea, grown under irrigation regime (30 + 30 mm of water) and fertilized with 50 kg·N·ha-1 before planting and with 40 kg·N·ha-1 at blossom growth stage, produced more total dry biomass and seed yield as compared with that grown under non-irrigated conditions and fertilized with 50 kg·N·ha-1 before planting only. In particular, irrigation and nitrogen fertilization at blossom growth stage increased total dry weight of chickpea by 18.3% and 18.5%, respectively, as compared with that of non-irrigated and fertilized with N before planting. The corresponding increase of seed yield was 30.5% and 20%, respectively. The total dry biomass of “Amorgos” was 10% and 13% greater than that of “Serifos” and “Andros”, while its respective seed yield increase was 5% and 16%. Finally, the quantum yield of photosystem II of chickpea was not affected by irrigation or fertilization. These results indicated that nitrogen fertilization at blossom growth stage combined with irrigation increased seed yield of all chickpea varieties, whereas the same treatments did not have any effect on plant quantum yield of photosystem II.

Effects of Varieties and Cooking Methods on Physical and Chemical Characteristics of Cooked Rice

To analyze the effect of different lowland rice varieties and different cooking methods on physical and chemical characteristics of cooked rice. A factorial randomized block design with two factors was used and each combination of the factors was repeated three times. The first factor was rice variety（Ciherang and Ciliwung） and the second factor was the cooking method（stovetop, boiling and steaming, and rice cooker）. Results showed that Ciherang and Ciliwung varieties were classified into slender grain rice type with yellowred color. The amylose content of Ciherang was classified as moderate, while the amylose content of Ciliwung classified as low. The most abundant amino acid contained in Ciherang and Ciliwung varieties was glutamic acid. Statistical analysis showed that cooking method had significant effects on texture, lightness, chroma, hue and moisture content of cooked rice. Rice cooked with liwet method had the lowest texture value, lowest lightness value, highest chroma value, and highest moisture content.

Selection of Trichoderma mutants with enhanced cellulase production and resistant to catabolite repression

Due to high cost and relatively low efficiency of cellulase enzymes used for the saccharification of pretreated lignocelluloses, the improvement of cellulase secreting microorganisms is of vital importance. Trichoderma reesei QM 6a, an excellent source of cellulase was selected in the late 1960’s. at Natick Laboratories by its performance on pure cellulose (Solka Floc, Avicel) . QM 6a is the wild parent strain of best existing hypercellulolytic mutants such as Rut C30, VTT-D-80133, L27, CL-847 and others. Utilization of cheaper carbon sources (e.g., pretreated wood or straw) both in enzyme production and in hydrolysis necessitates to investigate fungal species other than T.reesei. A screening program was initiated to test 150 wild-type Trichoderma strains in shake flask for cellulase production on SO 2-impregnated and steam pretreated spruce and willow, candidate substrates for bioalcohol program in Sweden. Filter paper activity (FPA) method was used to determine the overall cellulase activity. Strain TUB F-1505 was selected as promising candidate for mutagenesis. This wild strain was isolated from a tropical rain forest area near Manaus, Brazil. Isolate F-1505 was subjected to NTG-mutation to select catabolite (glucose, glycerol) resistant mutants. A Petri plate clearing assay using Walseth cellulose, glycerol or glucose and Triton X100 (colony size inhibitor) was applied for pre-screening of the colonies. Over 6000 colonies were evaluated. Best colonies were tested in shake flask fermentation on pretreated spruce and willow as carbon sources. Mutants producing higher levels of cellulase (FPA) were further mutated by either NTG or UV-light. At least 4 mutants were obtained and freeze-dried exhibiting equivalent or higher cellulase production as compared to Trichoderma reesei Rut C30.

Trichoderma spp. capable of growing at low temperatures with biocontrol potential

@Szakacs G$Technical University of Budapest, Department of Agricultural Chemical Technology, 1111 Budapest, Gellert ter 4, Hungar@Tavaszi A$Technical University of Budapest, Department of Agricultural Chemical Technology, 1111 Budapest, Gellert ter 4,

Production of chitinases with Trichoderma harzianum isolates using solid substrate fermentation

Over forty Trichoderma harzianum isolates have been screened in solid substrate fermentation (SSF) for chitinase production. Strains were isolated from Asian soil and tree bark samples. Identification was performed in Canada and Austria by classical and molecular taxonomical methods. Four SSF media were used for the screening. They contained wheat bran, crude chitin from crab shells (SIGMA) and different salt solutions for wetting of the substrate. In a five day fermentation at 30°C the best chitinase producers were T. harzianum TUB F-691, TUB F-693, TUB F-699, TUB F-700, TUB F-927, TUB F-947 and TUB F-972 isolates (TUB = Technical University of Budapest culture collection) . The best producers yielded between 3.5-5.5 International Unit/g dry matter (DM) chitinase. T. harzianum TUB F-947 was selected for further optimization. This strain was isolated from a soil of Thailand. The optimum moisture content (67%), optimal alternative substrate-carrier for SSF (wheat straw) and chitin content of the substrate (30%) were determined. Temperature and pH optima of chitinase produced by T. harzianum TUB F-947 were found to be at 50°C and 5.0, respectively. The enzyme complex was thermally not stable at 50 ℃. Medium optimization experiments to enhance the chitinase production using statistical methods also have been performed.

Biodiversity of Trichoderma spp. in TUB culture collection

Culture collection of the Technical University of Budapest (TUB) comprises app ro x. 2800 microorganisms with special emphasis on lignocellulose degrading fungi a nd actinomycetes. For isolation and screening programs, 460 soils are stored at +5 ℃. They were collected in 58 countries, including extreme environments. There are 860 Trichoderma strains in TUB collection, representing 45 count ries and 173 soils and/or tree barks as isolation sources. Trichoderma spp . selected from soils in the tundra region (Rocky Mountains, Colorado) grow at l ow temperatures such as 5-10 ℃. These strains practically do not grow at 30 ℃ . On the contrary, many Trichoderma strains were isolated from tropical or s ubtropical soils and decaying plant materials at 35-40 ℃ in Brazil, Peru, Cost a Rica, Guatemala, Hawaii, Tanzania, Thailand and Indonesia. Trichoderma str ains tolerating limited oxygen supply were selected from river muds and sediment s. Trichoderma spp. tolerating or partially degrading 2,4-dichlorophenol a nd 2,4,6-trichlorophenol in 20 mg/kg concentration were selected from polluted soils. As a part of an attempt to assess the global biodiversity of Trichoderma, researchers of Technical University of Vienna and Agriculture Canada, in collab oration with TUB collection, identified and characterized seven new assumed taxa of Trichoderma from Eurasia.

Effectiveness of Ringworm Cassia and Turmeric Plant Extracts on Growth Inhibition against Some Important Plant Pathogenic Fungi

Crude plant extracts of ringworm cassia, Cassia alata L. and turmeric, Curcuma longa L. were prepared by either hot water or organic solvents such as ethanol and ether. Various concentrations of the crude extract were then subjected to an in vitro test for their effectiveness on mycelia growth inhibition against some important plant pathogenic fungi such as Alternaria alternata, Colletotrichum gloeosporioides, Fusarium oxysporum fsp. lycopersici, Sclerotium rolfsii, Phytophthora infestans and Pythium sp. in comparison to commercial fungicides such as copper oxychloride and mancozeb. Reduction of the fungal growth was significantly obtained with C. longa extracts and the best median effective inhibitory concentration (IC50) value of 6.07, 6.50 and 7.13 mg/ml was from the ethanol extract for S. rolfsii, C. gloeosporioides and F. oxysporum fsp. lycopersici respectively. While all extracts from C. alata were almost the least effective against these fungi. The efficacy of C. longa extracts therefore, provided an alternative regime for the control of the fungal diseases and a promising appreciable choice for a replacement of chemical fungicides.

Enzymes of Trichoderma and other origin in biopreparation of cotton

Preparation and bleaching are among the most energy and chemical intensive steps of the traditional cotton finishing. About 75% of the organic pollutants arising from textile finishing are derived from the preparation of cotton goods. Biopreparation may be a valuable and environmentally friendly alternative to harsh alkaline chemicals for preparing of cotton. Different enzymes i.e. cellulases, pectinases, lipases and proteases have been tested for biopreparation. Many papers have been published how enzymes effect on the properties of cotton fabrics in respect to their effectiveness to replace alkaline scouring and how enzymes modify the various cell wall components of cotton fibers. However, very few data have been reported on bleachability and dyeing behavior of the bioscoured fabrics. In this work an acidic cellulase (Celluclast 1.5 L, Trichoderma reesei origin), an acidic pectinase-hemicellulase (Viscozyme 120 L , Aspergillus aculeatus) and a cellulase-free xylanase (Pulpzyme HC, Bacillus sp.) enzymes were used for bioscouring of greige cotton fabric. Selected properties of the pretreated samples, which are important for effective dyeing, are characterized in detail. Effect of hydrogen peroxide bleaching, applied subsequent to the biopretreatment on the bleachability and dyeing properties of the samples is also elucidated. A reactive dye was used at four different concentrations to compare the dyeing behavior of biopretreated as well as biopretreated and subsequently bleached cotton fabrics with that of the alkaline scoured as well as alkaline scoured and bleached fabrics, respectively. Color evenness and uniformity, and wash fastness properties of the dyed samples are also determined [1]..

Influence of Heating Time of Shea Nuts (vitellariaparadoxa) on Some Chemical Properties of Shea Butter

The experiment was conducted in the laboratories of the Departments of Chemistry and Animal Health and Production Technology, Adamawa State University, Mubi, Nigeria. The experiment was replicated three times in a Randomized Complete Block Design (RCBD) and consisted of six heating time 30, 60 and 120 minutes boiling, 30, 60 and 120 minutes roasting and one control. Data were collected on acid value, free fatty acid, iodine value, peroxide value, saponification value and unsaponifiable matter. The data collected were analyzed statistically using Generalized Linear Model (GLM) procedure of statistical analysis system (SAS). The means that were significantly different were separated using Least Significant Difference (LSD). The results showed that there were highly significant differences (P ≤ 0.01) among the treatments. The highest Acid Value (AV) of 3.53 and 3.64 were recorded by heating time at 120 minutes of boiling and 120 minutes of roasting. Heating time at 30 minutes of boiling, 30 minutes roasting, 60 minutes boiling and 60 minutes roasting recorded lower Free Fatty Acid (FFA) values of 1.52, 1.55, 1.57 and 1.58, respectively. Heating time at 60 minutes of roasting and 60 minutes of boiling recorded the highest Iodine value (IV) of 43.80 and 43.53, respectively. Based on the results of this study, it can be concluded that heating time of 30 or 60 minutes by boiling or roasting are better than longer heating times for Shea butter extraction.

Specificity of Various Mitochondrial DNA (<i>mt</i>DNA), <i>ND5</i>, <i>D-Loop</i>, and <i>Cty-b</i>DNA Primers in Detecting Pig (<i>Sus scrofa</i>) DNA Fragments

Polymerase Chain Reaction (PCR) is an accurate, simple and fast analytical method. This technique is widely used in the identification of meat adulteration and meat-based processed food products. Three Mitochondrial DNA (mt-DNA) primers NADH Dehydrogenase sub unit 5 (ND5), D-Loop, and Cytochrome b (Cyt-b) were tested for their specificity in detecting of pig (Sus scrofa) DNA fragments. DNA genome from 6 meat samples (pork, beef, goat, lamb, and chicken) was amplified by PCR technique using three pairs of primers (ND5, D-Loop, and Cyt-b) and sequenced. The results of amplification using the three primers produced specific DNA bands with the lengths of 232 bp, 951 bp, and 404 bp, respectively. Comparison results with ND5, D-Loop, and Cyt-b gene sequences resulted in similarity values of 100%, 97%, and 99%, respectively. These showed that the mt-DNA primers of ND5, D-Loop, and Cyt-b genes can be recommended as specific primers in detecting pig (Sus scrofa) DNA fragments.

The Influence of Organic Manure and Biochar on Cashew Seedling Performance, Soil Properties and Status

A nursery experiment was conducted at Cocoa Research Institute of Nigeria to evaluate the impact of manure on cashew seedlings. Treatments consisted of biochar, compost, combination of biochar + compost and a control. Treatments were applied at rate of 0 g (control), 5 g compost, 5 g biochar and 2.5 g each of biochar and compost combination into 5 kg soil in pots, laid out in a completely randomized design (CRD) with three replications. The experiment was monitored for four months in the greenhouse. Data were collected on number of leaves, plant height, stem girth, soil nutrient composition and nutrient uptake, all analyzed using analysis of variance. The treated soils were also assayed on Potato Dextrose Agar for associated mycoflora. The study showed that the soil PH, N, P, K, Ca and Mg were equally enhanced significantly relative to the control, while Aspergillus, Trichoderma, Beauverie, Penicillium, Lasiodiplodia and Rhizopus cultured treated soils shows that Trichoderma harzianum and Beauverie bassiana were significantly higher in combination of biochar and compost treated soil and posed that their bio-control potential is coupled with soil fertility enhancement characteristics. The results also indicate that stem girth and number of leaves were significantly (P ≤ 0.05) different with respect to applied treatment at the first month after treatments application. The leaf area was not enhances with the application of biochar. Combination of biochar + compost significantly enhanced number of leaves and stem girth at the 4th and 12th weeks after planting. Similarly leaf K and P uptake were significantly (<0.05) increased by the application of organic compost and biochar irrespective of whether combined or not compared to the control seedlings. The effect of biochar and compost on cashew leaf Ca and Mg uptake were not significantly different from the control but had a higher value relative to the control. It could therefore be recommended that addition of compost and biochar for sustainable production of cashew seedlings in the nursery be embraced by prospective cashew farmers and seedlings distribution in Nigeria.

中波紫外线UV-B辐射对酸橙(Citrus latifolia Tan).果实采后贮藏中叶绿素降解酶活性和品质的影响

研究了中波紫外线(UV-B)辐射对酸橙果实采后贮藏过程中叶绿素降解酶活性和果实品质的作用效果。将绿熟的酸橙果实用19.0 kJ.m-2剂量的UV-B照射后,在25℃下避光贮藏,以未照射紫外线的果实为对照。结果表明,UV-B处理有效延缓了果实色度和叶绿素a含量的下降;果实叶绿素降解酶、叶绿素酶、叶绿素降解过氧化物酶和脱镁叶绿素水解酶活性受到抑制,并且脱镁螯合作用也被延缓。UV-B处理促使酸橙果实在贮藏过程中柠檬酸含量逐渐增加,同时抑制了糖含量的增加。此外,在贮藏过程中,处理和对照酸橙果实的抗坏血酸含量均有所下降,但对照果实的下降速度要高于处理果实。以上结果说明UV-B处理可以通过控制叶绿素降解酶的反应来有效抑制酸橙果实贮藏过程中叶绿素的降解,并改善绿熟酸橙的品质。