分阶段储粮降温通风的比较研究

采用试验观测的方法,对钢板仓仓储小麦分别进行不通风、两阶段和三阶段降温通风研究和分析。研究发现,相对于秋季两阶段通风而言,夏季增加一个通风阶段更有利于提高降温效果。在为期两年的试验中,在夏季合适的气温条件下,用较小的通风量进行降温通风,小麦有足够的时间与温度低于24℃的空气接触达到冷却的目的。然而,由于夜间空气温度低、湿度大的特点导致粮食最终温度高于24℃,同时由于送风湿度大的原因,粮食的水分也会相应增大。     

Sponge-associated fungi from a mangrove habitat in Indonesia: species composition,antimicrobial activity,enzyme screening and bioactive profiling

There is no report of diversity, biological properties and bioactive compounds of sponge-associated fungi from Indonesia’s mangrove ecosystem to date. This study was designed to isolate sponge-associated fungi from a mangrove ecosystem in Mangkang, to screen the antimicrobial and extracellular enzyme properties of the isolates, characterize the biologically promising isolates using molecular approaches, and profile the secondary metabolites using phytochemical and thin-layer chromatography (TLC) analyses. An unidentified sponge that lived in association with mangrove roots was collected from Mangkang. Total of eight associated fungi were isolated from the sponge. Among all isolates, only two fungi SPMKF 1 and SPMKF 6 produced extracellular amylase, another two fungi SPMKF 4 and 5 showed antibacterial activity against MRSA, and only one fungus SPMKF 8 was able to produce extracellular amylase and show antimicrobial activity against ESBL E. coli, Salmonella enterica ser. Typhi strain MDR and C. albicans, while SPMKF 2, SPMKF 3 and SPMKF 9 did not show any biological properties. The result of genetic characterization proved that SPMKF 1 was Cladosporium tenuissimum, SPMKF 4 was Eutypella sp., SPMKF 5 was Lasiodiplodia theobromae, SPMKF 6 was Fusarium keratoplasticum and SPMKF 8 was F. solani. Furthermore, an amylase gene was detected in fungi SPMKF 1, 6 and 8 while among the BGC, only NRPS genes were detected in SPMKF 4, 5 and 8. Interestingly, several same metabolites indicating the same retention factor (Rf) values in TLC were detected in the fungal crude extracts by TLC.     

Modified complementation test of male sterility mutants in pepper (Capsicum annuum L.): preliminary study to convert male sterility system from GMS to CMS

The male sterility system in hybrid seed production can eliminate the cost of emasculation and ensure seed hybridity through avoidance of self pollination. GMS and CMS are two types of male sterility system that currently employed in pepper breeding. Conversion from GMS to CMS will increase the male sterility proportion of female parent from 50 to 100%. In this study, segregation analysis of four male sterile mutants consisting of one CMS mutant (CA1) and three GMS mutants (GA1, GA3 and GA4) showed that each had single recessive gene inheritance. A modified complementation test was performed by replacing male sterile mutants with their maintainer line as male parent. The nuclear restorer gene for CMS was independent of all nuclear restorer genes for GMS and all nuclear restorer genes for GMS were independent each other. Further observation on CMS and GMS male sterility loci revealed that GA1 and GA3 had mutated in both nuclear restorer genes for CMS and GMS, while CA1 and GA4 each carried mutation in single male sterility system of nuclear restorer gene for CMS and GMS, respectively. Conversion from GMS to CMS in the case of lines carried mutations in both sterility systems required only S-type cytoplasm donor, while lines carried mutation in single nuclear restorer gene for GMS required not only S-type cytoplasm but also rf allele donors. The important finding is the broader function of maintainer line in certain male sterility system that can be used as a maintainer or restorer line for other male sterility systems. We also confirmed that line CC1 is the general restorer for both CMS and GMS systems.     

Polycitorols A and B,New Tricyclic Alkaloids from an Ascidian

Two new tricyclic alkaloids, polycitorols A (1) and B (2) have been isolated along with the known lepadiformine (3) from a marine ascidian of the family Polycitoridae. The structures of the new compounds were elucidated by analysis of NMR data and comparison with those of 3 and other related compounds [1–5]. Compounds 1 and 2 are closely related to cylindricines A and B, lacking C-4 oxygenation found in cylindricines and having a butyl instead of a hexyl appendage. NOE experiments on compounds 1 and 2 suggested the A/B ring fusion to be cis.     

Screening of Indonesian plants for tyrosinase inhibitory activity

In our efforts to find new tyrosinase inhibitory materials, we investigated 44 Indonesian plants belonging to 24 families for tyrosinase inhibitory activity. The extracts of 5 Artocarpus woods showed potent tyrosinase inhibitory activity (over 80% at 100 μg/ml) similar to a positive control, kojic acid. In Artocarpus woods, the extracts of the sapwoods showed stronger inhibitory activity than those of the heartwoods. Chlorophorin was isolated as one of the active compounds in the sapwood of Artocarpus heterophyllus. The content of chlorophorin in sapwood was higher than that in heartwood. Part of this paper was presented at the 53rd (Fukuoka, March 2003) and 54th (Hokkaido, August 2004) Annual Meetings of the Japan Wood Research Society, and the 5th International Wood Science Symposium (Kyoto, September 2004)     

Lymphocyte subsets and specific IgG antibody levels in clindamycin-treated and untreated dogs experimentally infected with Babesia gibsoni

This study was carried out to clarify the role of lymphocyte subpopulations and Babesia-specific antibody on the treatment of clindamycin in dogs infected with B. gibsoni. Ten beagle dogs were divided into two groups: an untreated group (5 dogs) and a clindamycin-treated group (5 dogs), which was administered clindamycin at 25 mg/ kg body weight, per os, q 12 hr from 7 days to 21 days post-infection (PI). On the acute stage of infection, clindamycin treatment resolved anaemia and other clinical findings. There were no significant differences between treated and untreated dogs either in parasitemia levels or Babesial IgG antibody levels. However, morphological changes that indicated degeneration in the majority of parasites were observed. The numbers of CD4(+) showed a significant increase in treated dogs, especially after treatment. On the chronic stage, CD4(+) cells maintained high level both of the treated and untreated dogs. Although parasitemia maintained low level, their relapses were occurred on the 49th day PI in treated dogs and on the 42nd and 63rd PI in untreated dogs. A rapid humoral antibody response was observed in treated dogs, however, lower humoral antibody responses in untreated dogs after relapses. The antibody levels of treated dogs were significantly higher than those of untreated dogs. These results suggested that clindamycin might not eliminate rapidly parasites from peripheral blood, but damage parasites, which might stimulate efficiently humoral and cellular immunity against Babesia infection, and result in an improvement of clinical conditions.     

A Promising Potential of Brown Algae Sargassum polycystum as Irreversible Hydrocolloid Impression Material

This study aimed to investigate the potential use of brown algae Sargassum polycystum as irreversible hydrocolloid (alginate) impression material. Potassium alginate extracted from Sargassum polycystum was prepared in three different compositions (14%, 15%, and 16%) and mixed with other standard components to form an alginate impression material. Prior to that, the purity of potassium alginate was quantified with Fourier Transform Infrared Spectroscopy (FTIR) analysis. As a control material, the alginate impression material from a commercially available product was used. All alginate impression materials were then applied to a die stone model. Dimensional accuracy was measured by calculating the mesiodistal width of incisors in the generated dental cast using a digital caliper 0.01 accuracy (five replications). In addition, to evaluate the dimensional stability, the impression results were poured at four different periods (immediately, 5 min, 10 min, and 15 min). An independent t-test was performed to compare the measurement results with p < 0.05 considered significant. Analytical results confirm that the impression material containing 15% potassium alginate gives the best dimensional accuracy similar to control (p > 0.05). Meanwhile, the optimal dimensional stability was produced in the impression material containing 16% potassium alginate. Our study suggested that brown algae Sargassum polycystum has a promising potential to be used as an alginate impression material in clinical application.     

Therapeutic effect of clindamycin and tetracycline on Babesia rodhaini infection in mouse model

In order to identify the alternative effective chemotherapeutic agents for murine babesiosis, some selected drugs were examined for their efficacy against protozoan infection in the mouse-Babesia rodhaini (B. rodhaini) model. Clindamycin was not completely effective for elimination of parasites in a dose of 50 mg or 100 mg/kg BW/day b.i.d. but effective to prolong the life span of hosts, while it completely cured B. rodhaini infections in a dose of 200 mg. On the other hand, a double therapy consisting of 2 treatments with 100 mg clindamycin and 100 mg clindamycin and with 100 mg clindamycin and 100 mg tetracycline; respectively, and a single therapy with 100 mg tetracycline or 200 mg clindamycin, had a possibility to clear away B. rodhaini organisms from hosts. However, almost all the treatment groups, had a relapse of the infection within 10 days post treatment or re-treatment. Cured mice by treatment with clindamycin and clindamycin, or clindamycin and tetracycline showed complete resistance against challenge with B. rodhaini, while mice cured by administration of clindamycin at 200 mg or tetracycline at 100 mg showed incomplete resistance to challenge infection. The present data suggest that the two former chemotherapies can induce effective protective immunity (premunization), but the latter two chemotherapies induce incomplete premunization.     

Identification of potent odorants in different cultivars of snake fruit [Salacca zalacca (Gaert.) Voss] using gas chromatography-olfactometry

Three cultivars of snake fruits, Pondoh Hitam, Pondoh Super, and Gading, were freshly extracted using liquid-liquid extraction. The aroma compounds of the three samples were analyzed by GC-MS and GC-olfactometry using the nasal impact frequency (NIF) method. A total of 24 odor-active compounds were associated with the aroma of snake fruit. Methyl 3-methylpentanoate was regarded as the character impact odorant of typical snake fruit aroma. 2-Methylbutanoic acid, 3-methylpentanoic acid, and an unknown odorant with very high intensity were found to be responsible for the snake fruit's sweaty odor. Other odorants including methyl 3-methyl-2-butenoate (overripe fruity, ethereal), methyl 3-methyl-2-pentenoate (ethereal, strong green, woody), and 2,5-dimethyl-4-hydroxy-3[2]-furanone (caramel, sweet, cotton candy-like) contribute to the overall aroma of snake fruit. Methyl dihydrojasmonate and isoeugenol, which also have odor impact, were identified for the first time as snake fruit volatiles. The main differences between the aroma of Pondoh and Gading cultivars could be attributed to the olfactory attributes (metallic, chemical, rubbery, strong green, and woody), which were perceived by most of the panelists in the Pondoh samples but were not detected in the Gading samples. This work is a prerequisite for effective selection of salak genotypes with optimal aroma profiles for high consumer acceptance.