International Letters of Natural Sciences Vol. 60

Abstract: Tamarix L. with almost 54 species is the largest genus of the Tamaricaceae. This study was carried out on species of Tamarix that growing in Iran. Morphological characters were obtained for 23 species recognized by recent taxonomic treatments from Iran. In this study we use 10 characters to identify species of Tamarix that growing in Iran. For SEM studies, we used dry sampels of leaves and flowers. Some characters are useful for segregating certain species, such as gross leaf morphology (vaginate vs. sessile), number of floral parts, certain aspects of androecial disk morphology, petal shape, presence or absence of hairs on the raceme rachis, and whether the filament is inserted under or from the side of the androecial disk. In some species the number of sepals, petals and stamens are constant and reliable. One of the problems in Tamarix is that in many species the number of certain floral organs is inconstant thus the number of floral parts alone can not serve as a diagnostic marker without being correlated with the relative position of the organs and their range of numerical variability.

Abstract: The blood creatinine, some blood enzymes, glutamic oxaloacetic tranaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) have been determined in four locally available Indian carp fishes such as Labeo rohita, Catla catla, Cirrhana mrigala and Labeo fimbriatus to assess the kidney functioning in these fishes in relation to the aquatic body and their successful survival. The results indicate that the blood creatinine level is low with more or less uniform values in all the four species of fish. The higher values were observed for the two blood enzymes (SGPT and SGOT) in all the four types of fishes compared to the fish, Notopterus notopterus from our earlier studies and also reported in other fishes. Thus indicating normal functioning of kidneys and other organs in all the four types of fishes studied which are healthy and are probably not stressed.

Abstract: Abstract- The present investigation was carried out to evaluate the effect of different growth conditions on lipase production by Aspegillus niger. The extracellular lipase producing fungus was isolated from spent bleaching earths. Optimization of physical and chemical parameters was done for maximum lipase production using this isolate. Growth of the organism and lipase production were measured usig varying pH (4 – 9), incubation temperature (20 – 30 °C), incubation time (8 – 80 hrs.), carbon sources, nitrogen sources, and shaking speed. Enhanced lipase production was observed at 24 °C, pH 7 and after 72hrs of incubation. Olive oil 5 % was observed as the most effective carbon source and Yeast extract 1.0 % as the most effective nitrogen source for lipase production. The optimum shaking value to get maximum lipase activity by Aspergillus niger was 200 rpm.

Abstract: The research was designed to extend shelf life of stored strawberry by bioactive chitosan coating. Strawberry fruits were dipped for 2 min in different concentration of irradiated chitosan (300, 500, 1000 and 1500 ppm) solution which were subjected to different gamma radiation doses (30, 40, 50 and 60 kGy) while uncoated fruits were served as control. Samples were packed in zip bags and stored in 4°C and kept for observation. Fruits treated with 50 kGy irradiated chitosan at 1500 ppm concentration showed significant delays in the change of weight loss, decay percentage, pH, and ascorbic acid content as compared with the uncoated control fruits. Samples stored in 4°C and packed in zip bags showed an increased shelf life up to 21 days whereas control samples with same condition could maintain edible quality only up to 3 days. Compared to the controls, all coating formulations had positive effect on the inhibition of cell wall degrading enzymes. These findings suggest that the use of irradiated chitosan coatings can be very useful for extending the shelf-life and maintaining quality of strawberry fruit.

Abstract: A new modified protocol has been developed for extracting pure community inhibitors-free DNA from saline soils, sediments and salts. Amplification of DNA from soil and sediment is often inhibited by copurified contaminants. A rapid, inexpensive, large-scale DNA extraction method involving minimal purification has been developed that is applicable to saline samples. Using a widely used a newly modified direct DNA extraction method proposed in this report, DNA was extracted from samples of Urmia Lake in diverse geological location in Iran and quantity of the DNA were examined. We developed an improved method to extract DNA include the combination of physical, chemical and mechanical lysis methods from saline samples. In the earlier reports, skim milk as an adsorption competitor was added to buffer DNA extract. In current study, we added skim milk to buffer DNA extraction. The results showed that skim milk was useful as an additive for extract DNA from saline samples. This method is applicable to molecular community analysis of saline samples which strongly adsorb DNA. The methods appear to have wide applicability in investigating molecular diversity and exploring functional genes from the total DNA. The extracted DNA was used to successfully amplify 16SrRNA region and functional genes. The amplicons were suitable for further applications such as diversity based analysis by denaturing gradient gel electrophoresis (DGGE) and cloning library.

Abstract: A cross-sectional study was conducted to determine the prevalence and associated risk factors of trichinellosis in slaughtered pigs from three slaughterhouses located in Pyinmana, Lewe and Tatkon Townships, Nay Pyi Taw, Myanmar. Targeted population was 1,980 slaughtered pigs from those slaughterhouses and 90 pigs were randomly selected during the study period of January to March, 2012. A total of 270 muscle samples (tongue, masseter and diaphragmatic muscles from each pig) from 90 slaughtered pigs were collected and examined for the presence of Trichinella larvae by using artificial digestion method. Among the examined samples, three samples from three pigs (3.3%) showed Trichinella positive. Trichinella larvae were observed from two diaphragmatic muscles and one masseter muscle. In those positive samples, Trichinella larval intensity per gram (lpg) was 0.2. For the determination of associated risk factors of trichinellosis, questionnaire interviews to officials of slaughterhouses and owners of slaughtered pigs were conducted. Among the hypothesized risk factors, the presence of rodents around the pig farm and type of feed (use of uncooked waste feed) were identified as associated risk factors for trichinellosis. Age, gender, body weight, rearing system and use of anthelmintics appeared no association with porcine trichinellosis in this study.

Abstract: This study was conducted to assess the effect of common salt supplementation on the performance of young sheep fed maize bran and ground nut hay as basal diet. It covered a period of 12 weeks. A 3×3 Latin square design was employed in the experiment. The daily feed intake, body weight gain and feed conversion efficiency were measured during the experimental period. Results showed that the inclusion of common salt at the level of 1.0% of feed had no significant effect on feed intake (p>0.05). There was depressed feed intake as quantity of salt increased from 0.0%, to 0.5% and 1.0%. The best mean average daily weight gain of 43.45%was obtained with the 1.0% treatment. Salt inclusion up to 1.0% level in sheep ration, had no adverse effect on performance, it rather gave a more favorable weight gain and conversion efficiency. These findings are of very practical significance in sheep fattening, especially for farmers in rural setups.

Abstract: At present, probiotic bacteria are proposed as an important alternative for antibiotic elimination and for providing renewable products through biological control in cultivation systems of marine fish larvae. The aim of this study is to compare the effects of native and commercial probiotics on growth parameters of Persian sturgeon (Acipenser persicus) larvae fed with controlled biomar diet. Experimental diets with three probiotic bacterial mixture including commercial lactobacillus (L. plantarum and L. rhamnosus), commercial Bacillus (B. subtillis and B. licheniformis) and Bacillus isolated from intestine of Persian sturgeon (B. mycoides) were completed in two levels (6.1 and 7.2 log CFU in each g of feed) and were fed to larvae of Persian sturgeon in six experimental treatments. The control treatment was fed with diet without supplementation. The experiment was done in randomized design. In all the treatments, feed conversion index was increased considerably and had significant difference with control treatment and in all the experimental treatments influenced by probiotics were higher than that of control treatment (P<0.05). The highest rate means of special growth (1.84±0.21%) and thermal growth index (3.44±0.37%) was obtained respectively in treatment C1 and C2 (isolated from intestine). Maximum special growth rate (SGR %) were obtained from C1 (4.69±0.71%) and B2 (4.62±0.87%, commercial Bacillus). In addition, native probiotic bacteria had better performance than the non native commercial species as well as selection of suitable probiotic (natural) with respect to fish species, region and condition of culture plays a special importance role in enhancing the yield of Persian sturgeon larvae.