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Based on the traditional technology of alcohol from cooked sticky rice in Nam Dinh province, Vietnam, the experiments were conducted by the way to kept the technological process as well as the proportion of ingredients. The quantity of the sticky rice for every experiments was 10 kg. The obtained results showed that the addition of 0.05% enzyme SEBflo-TL compared to the dry matter of sticky rice leads to an increase of the absolute anhydrous alcohol by 10%. Combined application of 0.05% enzyme SEBflo-TL and 0.08% SEBrew-GL for hydrolysing starch and β -glucan, the amount of obtained anhydrous alcohol is 4.6 liters compared to 4.0 liters in the sample control without enzyme application, yield increased by 15% and could provide significant economic benefits to wine producer. In other hand, after the first distillation, the fractional distillation reduced concentration of metanol, acetaldehyde and improved volatile compounds of producted alcohol. The finished alcohol met the Vietnam National technical regulation for alcoholic beverages and are unlikely to cause toxicity to consumers.

Injection molding technology is known as the most widely used method in mass production of plastic products. To meet the quality requirements, a lot of methods were applied in optimization of injection molding process parameter. In this study the optimization based on Taguchi orthogonal array and Grey relational analysis (GRA) is used to optimize the injection molding process parameters on a LED lens. The four process parameters are: packing pressure, injection speed, melt temperature and mold temperature. The multi-response quality characteristics are total displacement, volumetric shrinkage, and thermal residual stress. The optimal molding parameters are packing pressure (90 MPa), injection speed (300 mm/sec), melt temperature (270 °C) and mold temperature (90 °C). The luminous uniformity of the LED is 92.61 % and the viewing angle of the LED is 124.76°. Among the four factors, packing pressure plays the key role in reducing total displacement, volumetric shrinkage, and thermal residual stress.

Chitinases play the key role in hydrolysis of chitin, a huge organic carbon reservoir on earth, into monomeric sugars and their eventual conversion into valuable chemicals and energy sources. The Lecanicillium lecanii strain 43H was used as the source for the Endochitinase gene without signal peptide (mchit1). This mchit1 gene was cloned and sequenced. The recombinant Endochitinase non signal peptide was overexpressed in Pichia pastoris X33 with a level of 2.048 U mL−1 culture supernatant. The molecular mass of the purified recombinant Endochitinase (rmchit1) without signal peptide was 43 kDa. Metal ions, detergents, and organic solvents tested indicated a significantly influence on rmchit1 activity. The obtained results demonstrated that signal peptides affect the yield expression, purification methods, recovery as well as the physicochemical properties of the enzyme.

The use of chemical fungicide has seriously damagedenvironmental soils, underground water, air and ecologicalenvironment, etc. Therefore, the use of biological fungi-cides originated from microbial antagonists to protect cropsfrom disease has been increasingly interested in proceedto replace chemical fungicides. High doses of chemical fun-gicides are used to protect crops but makes soils to bebarren, severely affecting the ecological environment.Especially, chemical residues on the agricultural productscause serious impact on human health. The developmentof microbial antagonists for production of plant fungicides isvery urgent and meaningful in organic agriculture. So far,several secondary metabolites producing bacteria havebeen considered as biocontrol agents of plant pathogenicfungi control. For example, Pseudomonas syringae synthe-size syringomycin, syringostatin and syringotoxin whichsuppress effectively pathogenic fungi of Aspergillus flavusand Fusarium oxysporum [4]. Besides, Pseudomonasstrains produce cepacin A and cepacin B [20], phenazine[25] and pyrrolnitrin [12] which inhibit growth of Rhizoctoniasolani, F. oxysporum [8]. Burkholdria cepacia strains pro-duce several antibiotics including cepacin and pyrrolnitrinwhich suppress the growth of both R. solani- and F.oxysporum [2, 13]. In Vietnam, a few papers have pre-sented the use of microbial cells, fungal spores for suppres-sion of plant pathogenic fungi. However, reports of cell freeextracellular compounds (ECs) of antagonists against plantfungal diseases are not much. The aim of this study was to

Improvement of endoglucanase activity was accomplished by utilizing error-prone rolling circle amplification, supplemented with 1.7 mM MnCl2. This procedure generated random mutations in the Bacillus amyloliquefaciens endoglucanase gene with a frequency of 10 mutations per kilobase. Six mutated endoglucanase genes, recovered from six colonies, possessed endoglucanase activity between 2.50- and 3.12-folds higher than wild type. We sequenced these mutants, and the different mutated sites of nucleotides were identified. The mutated endoglucanase sequences had five mutated amino acids: A15T, P24A, P26Q, G27A, and E289V. Among these five substitutions, E289V was determined to be responsible for the improved enzyme activity. This observation was confirmed with site-directed mutagenesis; the introduction of only one mutation (E289V) in the wild-type endoglucanase gene resulted in a 7.93-fold (5.55 U/mg protein) increase in its enzymatic activity compared with that (0.7 U/mg protein) of wild type.

Ethanol production by simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% of raw starch. RWC slurry was mixed with raw-starch-digesting enzyme of Rhizopus sp. and yeast for SSF. The yeast strain used was selected from 300 strains for RWC fermentation and identified as Saccharomyces cerevisiae KV25. High efficiency (94%) of ethanol production was achieved at optimal condition of uncooked RWC slurry containing 23.03% of starch. The optimal SSF condition determined was 1.125 unit of raw-starch-digesting enzyme per one gram of RWC, 30 degrees C of fermentation temperature, 4.5 of pH slurry, 36 h-age of seeding culture, initial yeast cell 2 x 10(7) per ml slurry, 17 mM urea as nitrogen additive, 0.25 mM Cu(2+) as metal ion additives, 90 h of fermentation time. In this optimal condition, ethanol production by SSF of uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.

Cellulose, which is the most abundant renewable resource, is a polysaccharide composed of β-D-glucopyranosyl units joined by 1,4-glycosidic bonds (Gardner and Blackwell, 1974; Kolpak and Blackwell, 1976). Because cellulose can be utilized to produce ethanol, it is a promising alternative energy source for the production of fossil fuels. Cellulose is degraded by cellulases to reducing sugars and fermented by yeast or bacteria to ethanol (Duff and Murray, 1996). Cellulases are produced by various microorganisms including Trichoderma sp., Chrysosporium sp., Fusarium sp., Sclerotium sp., Phanerochaete sp., Aspergillus sp., Schizophyllum sp. and Bacillus sp. (Selby and Maitland, 1967; Wood and Phillips, 1969; Toyama and Ogawa, 1975; Sternberg, 1976; Fan et al., 1987; Duff and Murray, 1996). Three major types of cellulases, endoglucanases (EC 3.2.1.4), exo-cellobiohydrolases (EC 3.2.1.91) and β-glucosidases (EC 3.2.1.21), have been identified to date (Coughlan, 1985; Coughlan and Ljungdahl, 1988). A reduction in the cost of cellulase production, an improvement in cellulase activity and an increase in sugar yields are all vital to reducing the processing costs of bioethanol from cellulosic substrates (Zhang et al., 2006). During ethanol production from lignocellulosics, cellulases play a very important role in the cellulose digestion process and so far the cost of cellulases is very expensive due to the large amounts required for cellulose digestion (Duff and Murray, 1996; Himmel et al., 1997; Schell et al., 2003; Sun and Cheng, 2002). Therefore, the improvement of microbial strains for the over-production of cellulases has attracted attention in the commercial fermentation process. The use of different mutagenic agents for strain improvement was demonstrated by Parekh et al. (2000). Additionally, treatment of F. oxysporum with ultraviolet (UV) followed by N-methyl-N'-nitro-N-nitrosoguanidine (NTG) was used to improve carboxymethyl cellulase (CMCase) production (Kuhad et al., 1994). Moreover, Chand et al. (2005) used simultaneous treatment with NTG, ethidium bromide and UV or NTG combined with ethidium bromide to create mutant fungi that produced more CMCase and filter paper cellulase (FPase) than wild type fungi. The purpose of this study was to screen microbial strains for the selection of a strain producing high level of cellulase and to improve the microbial strain further by mutation. In this study, γ-rays of Co60, UV and NTG were repeatedly and sequentially used to mutate the fungal strain to induce the hyper-production of cellulase.

The production of aerial conidia of Lecanicillium lecanii 41185, a highly virulent fungus, by solid-state fermentation was studied for use as a biocontrol agent against aphids. Among several agro-industrial solid media, steamed polished rice was found to produce the highest amount of aerial conidia. The optimal conditions for aerial conidia production were determined to be a 28.5% moisture content in the rice, 25℃ culture temperature, rice pH of 6.0, 75% ambient relative humidity, 4-dold seeding culture, 0.6% KNO3, and 12 d of culture time. The conidia yield increased from 5.7 × 10(9) conidia/g polished rice to 18.2 × 10(9) conidia/g polished rice following application of these optimized conditions.

Spores of Aspergillus sp. SU14 were treated repeatedly and sequentially with Co(60) γ-rays, ultraviolet irradiation, and N-methyl-N'-nitro-N-nitrosoguanidine. One selected mutant strain, Aspergillus sp. SU14-M15, produced cellulase in a yield 2.2-fold exceeding that of the wild type. Optimal conditions for the production of cellulase by the mutant fungal strain using solid-state fermentation were examined. The medium consisted of wheat-bran supplemented with 1% (w/w) urea or NH(4)Cl, 1% (w/w) rice starch, 2.5 mM MgCl(2), and 0.05% (v/w) Tween 80. Optimal moisture content and initial pH was 50% (v/w) and 3.5, respectively, and optimal aeration area was 3/100 (inoculated wheat bran/container). The medium was inoculated with 25% 48 hr seeding culture and fermented at 35℃ for 3 days. The resulting cellulase yield was 8.5-fold more than that of the wild type strain grown on the basal wheat bran medium.

Twelve strains of entomopathogenic fungi such as Lecanicillium lecanii, Paecilomyces farinosus, Beauveria bassiana, Metarhizium anisopliae, Cordyceps scarabaeicola, and Nomuraea rileyi were screened for aphid control. At 25 degrees C and 75% relative humidity (RH), among tested entomopathogenic fungi, L. lecanii 41185 showed the highest virulent pathogenicity for both Myzus persicae and Aphis gossypii, and their control values were both nearly 100% 5 and 2 d after treatment, respectively. Moreover, at an RH of 45% and in a wide temperature range (20-30 degrees C), L. lecanii 41185 also exhibited the highest virulence to M. persicae. The control value of M. persicae and the 50% lethal time (LT50) decreased significantly as the applied conidial concentration increased. The 50% lethal concentration (LC50) of the conidial suspension of this fungus was determined to be 6.55x10(5) conidia/ml. The control values of M. persicae resulting from the application of 1x10(7) and 1x10(8) conidia/ml were nearly the same and were significantly higher than that of 1x10(6) conidia/ml. The tested entomopathogenic fungi grew in a broad temperature range (15-30 degrees C). Lecanicillium strains showed optimum growth at 25 degrees C. The aerial conidia of Lecanicillium strains also could germinate in a broad temperature range (15-30 degrees C) and L. lecanii 41185 was the only strain with conidial germination at 35 degrees C.