Showing papers in "Turkish Journal of Biology in 2005"

Antibacterial Activity of Some Selected Indian Medicinal Flora

Abstract: Nine plants were screened for potential antibacterial activity. In evaluating antibacterial activity both aqueous and organic solvents were used. The plants screened were Sapindus emarginatus, Hibiscus rosa-sinensis, Mirabilis jalapa, Rheo discolor, Nyctanthes arbortristis, Colocasia esculenta, Gracilaria corticata, Dictyota spps., and Pulicaria wightiana. Antibacterial activity was tested against 6 bacterial strains, Pseudomonas testosteroni, Staphylococcus epidermidis, Klebsiella pneumoniae, Bacillus subtilis, Proteus morganii, and Micrococcus flavus. Two methods, Agar disk diffusion and Agar ditch diffusion, were used to study the antibacterial activity of all these plants. Ps. testosteroni and K. pneumoniae were the most resistant bacterial strains. S. emarginatus showed strong activity against the tested bacterial strains. Therefore, this can be selected for further investigation to determine its therapeutic potential. Its leaf extract can also be used as a lead molecule in combating the diseases caused by the bacterial strains studied.

Efficacy of Aqueous and Methanol Extracts of Some Medicinal Plants for Potential Antibacterial Activity

Abstract: Twelve medicinal plants were screened, namely Abrus precatorius L., Caesalpinia pulcherrima Swartz., Cardiospermum halicacabum L., Casuarina equisetifolia L., Cynodon dactylon (L.) Pers., Delonix regia L., Euphorbia hirta L., Euphorbia tirucalli L., Ficus benghalensis L., Gmelina asiatica L., Santalum album L., and Tecomella undulata (Sm.) Seem, for potential antibacterial activity against 5 medically important bacterial strains, namely Bacillus subtilis ATCC6633, Staphylococcus epidermidis ATCC12228, Pseudomonas pseudoalcaligenes ATCC17440, Proteus vulgaris NCTC8313 and Salmonella typhimurium ATCC23564. The antibacterial activity of aqueous and methanol extracts was determined by agar disk diffusion and agar well diffusion method. The methanol extracts were more active than the aqueous extracts for all 12 plants studied. The plant extracts were more active against Gram-positive bacteria than against Gram-negative bacteria. The most susceptible bacteria were B. subtilis, followed by S. epidermidis, while the most resistant bacteria were P. vulgaris, followed by S. typhimurium. From the screening experiment, Caesalpinia pulcherrima Swartz. showed the best antibacterial activity; hence this plant can be further subjected to isolation of the therapeutic antimicrobials and further pharmacological evaluation.

Indole Acetic Acid Production by the Indigenous Isolates of Azotobacter and Fluorescent Pseudomonas in the Presence and Absence of Tryptophan

Abstract: A total of 21 bacterial isolates (Azotobacter sp., 10 and fluorescent Pseudomonas sp., 11) were isolated from different rhizospheric soils in the vicinity of Aligarh city and characterized as per standard methods. These isolates were further tested for the production of indole acetic acid (IAA) in a medium with 0, 1, 2 and 5 mg/ml of tryptophan. A low amount (2.68-10.80 mg/ml) of IAA production was recorded by Azotobacter strains without tryptophan addition. Seven Azotobacter isolates showed high level (7.3 to 32.8 mg/ml) production of IAA at 5 mg/ml of tryptophan while at 1 and 2 mg/ml the production was in the range of 1.47 to 11.88 and 5.99 to 24.8 mg/ml, respectively. Production of IAA in fluorescent Pseudomonas isolates increased with an increase in tryptophan concentration from 1 to 5 mg/ml in the majority of isolates. In the presence of 5mg/ ml of tryptophan, 5 isolates of Pseudomonas produced high levels (41.0 to 53.2 mg/ml) of IAA while 6 other isolates produced IAA in the range of 23.4 to 36.2 mg/ml. Production of IAA was further confirmed by extraction of crude IAA from 3 isolates of Azotobacter (Azs1, Azs6 and Azs9 ) and three isolates of Pseudomonas (Ps1, Ps4 and Ps7) and subsequent TLC analysis. A specific spot from the extracted IAA preparation was found corresponding with the standard spot of IAA with same Rf value. Pseudomonas isolates (Ps1, Ps4 and Ps7) showed inhibitory effects on the growth of root elongation of Sesbania aculeata and Vigna radiata at all concentrations of tryptophan compared to the control. However, the isolates of Azotobacter (Azs1, Azs6 and Azs9) demonstrated stimulatory effects on both plants. Increasing the concentration of tryptophan from 1 mg/ml to 5 mg/ml resulted in decreased growth in both S. aculeata and V. radiata. On a comparative basis isolate Azs9 was most promising in promoting plant growth. On the other hand, high concentration of exogenous tryptophan could exhibit toxic effects on plant growth.

Antimicrobial effects of ocimum basilicum (labiatae) extract

Abstract: Ethanol, methanol, and hexane extracts from Ocimum basilicum Labiatae (sweet basil) were investigated for their invitro antimicrobial properties. A total of 146 microbial organisms belonging to 55 bacteria, and four fungi, and a yeast species were studied using a disk-diffusion and minimal inhibition concentration (MIC) method. The result showed that none of the three extracts tested have antifungal activities, but anticandidal and antibacterial effects. Both the hexane and methanol extracts, but not the ethanol extracts, inhibited three isolates out of 23 strains of Candida albicans studied. All three extract of O. basilicum were different in terms of their antibacterial activities. The hexane extract showed a stronger and broader spectrum of antibacterial activity, followed by the methanol and ethanol extracts, which inhibited 10, 9 and 6% of the 146 bacterial strains tested, respectively. The minimal inhibition zones (MIC) of the hexane, methanol, and ethanol extracts ranged from 125 to 250 µl/ml, 62.50 to 500 µl/ml, and 125 to 250 µl/ml, respectively. Ocimum basilicum Labiatae Ekstrakt›n›n Antimikrobiyal Etkisi Ozet: Ocimum basilicum Labiatae (sweet basil)'un etanol, metanol ve hegzan ekstraktlar›n›n antimikrobiyal ozellii invitro koflullarda araflt›r›ld›. 55 bakteri, 4 fungus ve bir mayadan oluflan toplam 146 mikroorganizma, disk difuzyon ve minimal inhibisyon konsantrasyonu (MIC) yontemleri kullan›larak cal›fl›ld›. Sonuclar, test edilen 3 ekstrakttan hicbirinin antifungal aktivite gostermediini fakat antikandidal ve antibakteriyal etkiye sahip olduunu ortaya koydu. Hem hegzan hem de metanol ekstraktlar› 23 Candida albicans turunden 3 tanesine karfl› inhibisyon etkisi gosterirken, etanol ekstrakt› gostermedi. O. basilicum'un 3 ekstrakt› da farkl› oranlarda antibakteriyal etki gosterdi. Hegzan ekstrakt›, metanol ve etanole ekstraktlar›na gore daha guclu ve genifl oranda antimikrobial etkiye sahip olup, test edilen 146 bakteri strainine karfl› s›ras›yla %10, 9, 6 oranlar›nda inhibisyon etkisi gosterdi. Hegzan, metanol ve etanol ekstraktlar›n›n minimal inhibisyon konsantrasyon (MIC) oranlar› s›ras›yla, 125-250 µl/ml, 62.50-500 µl/ml ve 125-250 µl/ml'dir

Pb2+ Biosorption by Pretreated Fungal Biomass

Abstract: The effect of pretreatment on the Pb 2+ biosorption capacity of fungal biomasses, Aspergillus versicolor, Metarrhizium anisopliae var anisopliae, and Penicillium verrucosum, was investigated For this purpose, the biomasses were subjected to physical treatments such as heat and autoclaving, and chemical treatments such as sodium hydroxide, formaldehyde, gluteraldehyde, acetic acid, hydrogen peroxide, commercial laundry detergent, orthophosphoric acid and dimethyl sulfoxide Dimethyl sulfoxide, hydrogen peroxide and gluteraldehyde increased biosorption of Pb 2+ in comparison with the A versicolor live biomass M anisopliae var anisopliae biomass pretreated with hydrogen peroxide, gluteraldehyde, commercial laundry detergent, dimethyl sulfoxide and formaldehyde significantly improved biosorption of Pb 2+ in comparison with live biomass Pretreatment with all methods of P verrucosum increased biosorption of Pb 2+ in comparison with live biomass The maximum biosorption capacity of A versicolor biomass subjected to dimethyl sulfoxide was 306 mg g -1

Comparison of Antibacterial Activities of Selected Species of Zingiberaceae Family and Some Synthetic Compounds

Abstract: This study describes the antibacterial activity of ginger (G), mangoginger (M) and turmeric (T) and mixtures thereof i.e. ginger and mangoginger (GM), ginger and turmeric (GT), turmeric and mangoginger (TM), and a mixture of peels (P) and 4 synthetic compounds (HC-1, HC-2, HC-3 and HC-4). Extracts of these compounds were studied on Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Both aqueous (heated and unheated extracts) and organic solvents, 1, 4-Dioxan, N,N,dimethylformamide (DMF), were used for antibacterial assay. Growth inhibition was evaluated by the disc diffusion and agar ditch methods. The antibacterial activity of heated extracts was greater than that of the unheated extracts of all the 3 spices alone or mixtures thereof against all the 3 bacterial strains. When the organic acid extracts were studied, the antibacterial activity of 1, 4-Dioxan extracts of T, GT and TM showed the highest activity against E. coli. The 1, 4-Dioxan and DMF extracts of M showed the highest activity against B. subtilis. The antibacterial activity of G in 1, 4-Dioxan showed the highest activity against S. aureus. Extracts in DMF did not show any activity. The synthetic compounds in 1, 4-Dioxan showed better antimicrobial activity than did DMF extracts. In conclusion, amongst the studied members of Zingiberaceae mangoginger and mixtures containing mangoginger showed maximum antibacterial activity and the synthetic compound HC-3 showed antibacterial activity equivalent to that of mangoginger. Both natural and synthetic compounds extracted in 1, 4-Dioxan gave better results. Therefore, these 2 compounds can be used as lead molecules in drug designing.

Exogenous Application of Gibberellic Acid Counteracts the Ill Effect of Sodium Chloride in Mustard

Abstract: The response of mustard (Brassica juncea (L.) Czern & Coss cv. Varuna) to presowing seed treatment with sodium chloride (NaCl) was investigated. The plants raised from treated seeds were sprayed with water or 10-6 M GA3 at the 30- day stage. The seeds imbibed in 1 or 10 mM of NaCl resulted in a decrease in dry mass, leaf chlorophyll content, carbonic anhydrase activity (E.C. 4.2.1.1), nitrate reductase activity (E.C. 1.6.6.1) and net photosynthetic rate at the 60-day stage, and pod number and seed yield at harvest. However, spray application of GA3 neutralized the ill effect of soaking treatment in NaCl (1 or 10 mM).

Enterotoxigenic Staphylococcus aureus in Raw Milk in the North of Palestine

Abstract: Enterotoxin genes (sea-see) in Staphylococcus aureus isolates recovered from milk of clinically healthy sheep and cows in the north of Palestine were determined using a polymerase chain reaction (PCR). Thirty-seven (37%) out of 100 S. aureus isolates were toxin gene positive. Four strains (10.8%) were sea-positive, 20 (54.1%) were seb-positive, 4 (10.8%) were sec-positive, 6 (16.2%) were sed-positive and 3 (8.1%) were see-positive. None of these enterotoxigenic isolates carried more than one toxin gene. This study indicates that the presence of enterotoxigenic S. aureus in raw milk can contribute to the sources of staphylococcal food poisoning in Palestine.

Antimicrobial Effects of Verbascum georgicum Bentham Extract

Abstract: The methanol extract of Verbascum georgicum Bentham (Scrophulariaceae) was investigated for its in-vitro antimicrobial properties. A total of 143 microorganisms belonging to 56 bacteria and 4 fungi and a yeast species were studied using the disk- diffusion method and microdilution assays. The results indicated that the methanol extract of V. geopgicum had an inhibitory effect on the growth of all Candida albicans isolates and 17 strains in 10 different species of bacteria, namely Bacillus amyloliquefaciens, B. subtilis, B. cereus, B. pumilus, B. megaterium, B. lentimorbus, B. licheniformis, Pseudomonas putida, P. syringae and Escherichia coli, at different concentrations ranging from 37.5 to 300 µg/ml. However, it did not show antifungal activity against the isolates of the 4 fungal species tested. Thus, the results suggest that V. georgicum extract possesses compounds with antimicrobial properties that might be utilized for developing new drugs. Verbascum georgicum Bentham Ekstrakt›n›n Antimikrobial Etkileri Ozet: Verbascum georgicum Bentham'›n metanol ekstrakt›n›n antimikrobiyal ozellii in-vitro ortamda araflt›r›ld›. Bir maya 4 fungus 56 bakteri turune ait 143 mikroorganizma disk-difuzyon ve mikrodilusyon yontemleri kullan›larak test edildi. Verbascum georgicum Bentham'›n metanol ekstrakt›n›n Candida albicans izolatlar›n›n hepsine ve Bacillus amyloliquefaciens, B. subtilis, B. cereus, B. pumilus, B. megaterium, B. lentimorbus, B. licheniformis, Pseudomonas putida, P. syringae, Escherichia coli turlerini iceren 10 farkl› bakteri turunun 17 suflunda 37.5-300 µg/mL' konsantrasyonlar›nda inhibisyon zonlar› oluflturduu tesbit edildi. Bununla birlikte test edilen 4 fungus turunun izolatlar›nda antifungal aktivite gostermemifltir. Boylece, bu sonuclara gore Verbascum georgicum Bentham'›n metanol ekstrakt›n›n antimikrobiyal ozellikte bileflikler icerdii ve bunun yeni ilac gelifltirilmesinde antimikrobiyal ajan olarak kullan›labilecei onerilebilir.

Effect of Carboxy Methyl Cellulose and Gum Arabic on the Stability of Frozen Dough for Bakery Products

Abstract: Extended storage of frozen dough resulted in changes in rheological properties, which cause increasing proofing time and ultimately lower loaf volume of bread. The main causes of these changes are ice crystallization, which damage the gluten network. The major objective of this research was to reduce ice crystallization in frozen dough by incorporation of hydrophilic gums such as carboxymethylcellulose (CMC), and gum arabic at different levels. The doughs were stored frozen up to 8 weeks. Bread characteristics were analyzed after every 15 days for specific loaf volume, external and internal characteristics. Specific loaf volume increased significantly with the addition of different levels of gums compared with the frozen control. Although the external and internal characteristics of bread deteriorated with storage time, addition of gum arabic and CMC improved the characteristics of bread as compared to control after each storage period.

Phytoplankton Biomass and Species Composition of Lake Gölbaşı (Hatay-Turkey)

Abstract: Seasonal distributions of phytoplanktonic organisms in Lake Golbasi were investigated in samples collected from 2 stations between May, 2001, and April, 2002. At each station, monthly sampling was performed from the surface water. The flora consisted of 41 taxa belonging to Bacillariophyta (24), Chlorophyta (12), Pyrrophyta (2), Cyanophyta (2) and Chrysophyta (1). During the 1-year study period, the most dominant group was Chrysophyta followed by Bacillariophyta, Chlorophyta, Cyanophyta and Pyrrophyta. The highest numbers of Chrysophyta were observed in both stations in May, 2001, January, 2002 and April, 2002. Bacillariophyta had the highest biomass in both stations, followed by Chrysophyta, Pyrrophyta, Chlorophyta and Cyanophyta. The monthly changes in diversity values were between 0.01 and 0.90. The lowest diversity value was observed in the first station in January, 2001. Lake Golbasi has mesotrophic characteristics due to the seasonal distribution of phytoplanktonic organisms. However, it will be necessary to conduct further physical and chemical analyses of the lake water to obtain more detailed information about the trophic status of the lake

Effect of Salinity on Growth Chemical Composition and Antioxidative Enzyme Activity of Two Malting Barley (Hordeum vulgare L.) Cultivars

Abstract: The effects of salinity on the growth, chemical composition and superoxide dismutase (SOD) and peroxidase (POX) activities of 2 malting barley (Hordeum vulgare L.) cultivars (Kaya and Scarlet) were studied. In 10-day-old seedlings, salinity stress was initiated by applying an appropriate amount of NaCl to water, and it lasted for 30 days. Salinity decreased growth of the cultivars significantly. Scarlet restricted entry of Na + and Cl - into root and translocation to leaves more efficiently than did Kaya. As a whole Scarlet produced a higher amount total chlorophyll under salinity than did Kaya. POX activity of the cultivars decreased with salinity up to 20 dS m -1 , and then increased. In contrast to POX, salinity increased the SOD activity of leaves. Compared to the control application, 5.31% and 16.34% increases were determined in SOD activity, in 10 dS m -1 salinity, for Kaya and Scarlet, respectively.

Effects of Mercury and Chromium on Peroxidase and IAA Oxidase Enzymes in the Seedlings of Phaseolus vulgaris

Abstract: Phaseolus seedlings (Phaseolus vulgaris L.) in light conditions were treated with 2 different concentrations of 2 heavy metals, mercury (0.05 mM and 0.4 mM) and chromium (0.5 and 1.0 mM). Mercury was given in the form of HgCl2 and chromium was given in the form of K2Cr2O7. Peroxidase activity was measured with 4 different hydrogen donors (ferulic acid, caffeic acid, pyrocatechol and pyrogallol). Both mercury and chromium inhibited root and hypocotyl length. The inhibition was about 50%-80%, depending on the concentration of the heavy metal. Peroxidase and IAA oxidase activities showed a clear inverse relation with growth. Seedlings treated with a lower concentration of mercury had similar activities to those treated with higher concentrations of chromium. The role of peroxidase and IAA oxidase activities in defense mechanisms in response to heavy metal toxicity is discussed.

Biological Control of Vector Mosquitoes by Some Common Exotic Fish Predators

Abstract: Predation experiments using Cyprinus carpio Linnaeus (1758), Ctenopharyngodon idella (Valenciennes 1844), Oreochromis niloticus niloticus (Linnaeus 1758) and Clarias gariepinus (Burchell 1822) were conducted against fourth instar Anopheles stephensi Liston (1901) larvae and pupae at varying prey and predator densities. The relative prey consumption rates of the four fish species for An. stephensi larvae and pupae during 24-hour experiments under laboratory conditions were C. gariepinus > C. idella > C. carpio > O. n. niloticus. Predatory efficacy was positively related with prey density and inversely related with water volume (search area). A significant decrease in larval abundance in dipper samples was observed at 30 and 45 days after introduction of fishes (30 individuals each) in field conditions. The efficacy of the fish under field conditions was also indicated by significant increases of larval mosquito abundance at 30 and 45 days after removal of fishes.

Emerging Vector-borne Diseases in a Changing Environment

Abstract: Vector-borne infectious diseases are emerging or resurging as a result of changes in public health policy, demographic and societal changes, insecticide and drug resistance, shift in emphasis from prevention to emergency response, genetic changes in pathogens in the last two decades of the twentieth century. Climate changes also can influence the emergence and reemergence of these diseases which are malaria, dengue, yellow fever, plague, filariasis, louse-borne typhus, lyme disease, trypanosomiasis, leishmaniasis and viral diseases. West Nile virus is just the latest example of this type of invasion by exotic virus. This paper will provide an overview of the distribution, reasons of emergence or reemergence of the important vector-borne diseases throughout the world. Cevre Deifliklikleri ile Ortaya C›kan Vektor-Kokenli Hastal›klar Ozet: Vektor kokenli infeksiyon hastal›klar›, 20. yuzy›l›n son y›llar›nda halk sal›¤› politikalar›ndaki deifliklikler, demografik ve sosyal deifliklikler, insektisit ve ilac direnci, koruma yontemlerinden acil tedavi yontemlerine kay›fl ve patojendeki genetik deifliklikler nedeniyle yeniden onem kazanmaya bafllam›flt›r. ‹klimsel deifliklikler de, malaria, deng, sar› humma, veba, filariasis, bit ile bulaflan tifus, lyme hastal›¤›, trypanosomiyasis, leiflmaniyasis ve viral hastal›klar gibi vektor kokenli hastal›klar›n yeniden ortaya c›k›fl›nda etkili olabilir. Bat› Nil virusu, ekzotik viruslar›n yay›l›m›na ait son ornektir. Bu makalede, onemli vektor kokenli hastal›klar›n da¤›l›m›, yeniden ortaya c›k›fllar›n›n nedenleri global olarak ozetlenmeye cal›fl›lm›flt›r.

Prophylactic Efficacy of Crushed Garlic Lobes, Black Seed or Olive Oils on Cholinesterase Activity in Central Nervous System Parts and Serum of Lead Intoxicated Rabbits

Abstract: The effect of lead on cholinesterase activity in various central nervous system (CNS) parts and in serum, and the potential of crushed fresh garlic lobes, black seed and olive oils to combat lead poisoning in rabbits were assessed. Oral administration of lead acetate elevated BLL compared to control and sodium acetate groups. This increase was a function of the experimental time. Treatment of animals with crushed fresh garlic lobes, black seed or olive oils lowered BLL, with garlic was the most effective. Lead caused progressive decrease in the activity of acetylcholinesterase in different brain regions and spinal cord allover the experimental periods examined. The enzyme inhibition is generally reached its significance (P < 0.05) after 10 and 20 days of lead acetate intake. Such alteration in cholinergic transmission suggests that lead is able to reach the CNS and exerts its neurotoxic effect. Serum acetylcholinesterase and butyrylcholinesterase were also inhibited. Treatment of animals with crushed fresh garlic lobes, black seed or olive oils improved the enzyme activity in the central nervous system and serum. However, garlic was the most efficient. The ability of garlic to reduce lead toxicity may relay in its antioxidant/chelating action. Supplementation of diets with garlic is recommended to improve the body burden of lead and hence to protect the organ function against lead toxicity.

Effects of Carbon Sources and Various Chemicals on the Production of a Novel Amylase from a Thermophilic Bacillus sp. K-12

Abstract: The amylase producer thermophilic Bacillus sp. K-12 was isolated from soil samples from Zeytinli hot spring in Kahramanmarafl. Enzyme synthesis occurred at 20-55 …C with an optimum of 42 …C. There was a slight variation in amylase synthesis within the pH range 4.5-10.5. Effects of various carbon sources and chemicals on α-amylase production were examined and maximum α-amylase production was obtained in a medium containing 1% starch in 60 h. MnSO4, ZnSO4 and EDTA inhibited α-amylase production of Bacillus sp. K-12.

Changes in Antioxidative Enzymes of Young and Mature Leaves of Tomato Seedlings under Drought Stress

Abstract: The effects of exogenous abscisic acid (ABA) on antioxidant enzymes of young and mature leaves of 4-week old Lycopersicon esculentum cv. Ailsa Craig and ABA-deficient mutant, notabilis, were investigated under drought stress. Although ABA induced increases in ascorbate peroxidase (APX), glutathione reductase (GR) and catalase (CAT) activities in drought-stressed young leaves of notabilis, CAT activities remained unchanged in both ABA-treated young and mature leaves of Ailsa Craig under drought. Superoxide dismutase (SOD) activity did not substantially increase in notabilis or Ailsa Craig in all treatments. APX activity significantly increased in ABA-, drought- and drought+ABA- treated young leaves of notabilis. These results indicated that the antioxidant enzyme activities in drought-stressed and ABA-treated leaves might change with the production of active oxygen species (AOS) depending on the ABA content, and the developmental stages of leaves might contribute to the differential prevention of oxidative damage in plants exposed to drought.

The Effect of Acid Adaptation Conditions on Acid Tolerance Response of Escherichia coli O157: H7

Abstract: This study examined the effects of acid shock and acid adaptation on acid tolerance of E. coli O157: H7 932 strain. E. coli O157: H7 were exposed to acid at pH 4.5, 5.0 or 5.5 for acid adaptation or acid shock in tryptic soy broth (acidified with 6 N HCI). Acid shocked cells were incubated for 1, 2, 3 or 4 h while acid adapted cells were incubated for 18 h at 37iC and then acid tolerance of acid shocked and acid adapted cells were determined by exposing to acid challenge of pH 2.5 or 3.0 in tryptic soy broth. Acid shocked, acid adapted and control cells were incubated at 37iC and survival of the cells at 0, 2, 4, 6, 7, 24 and 48 h was determined. Acid shock increased acid tolerance of E. coli O157: H7 at pH 3.0. However, acid tolerance was not induced in acid adapted cells at either pH 2.5 or 3.0. Acid shocked cells exposed to acid at pH 4.5 for 2 h had the highest acid tolerance (P < 0.05). The results indicated that exposure to acidic environments (pH 4.5- 5.5) for a short time increased acid tolerance of E. coli O157: H7. Acid shocked cells of E. coli O157: H7 may be considered in fermented foods, fruit juices and for acid spray process in the meat industry.

High Quality DNA Isolation Method for Chickpea Genotypes

Abstract: In chickpea breeding genetic studies of individual plants need to be evaluated at the DNA level using molecular markers. A simple and reliable DNA extraction method is a prerequisite. This small-scale method is cetyltrimethylammonium bromide (CTAB)-based and extracts DNA from 1 to 3 folded young leaves processed in a 1.5 ml tube with 0.5 ml of extraction buffer and homogenized using an electric drill. Compared with the micro-prep method the improved mini-prep CTAB method is highly efficient and much cheaper in terms of time, chemical use and labor input. About 49 samples per day can easily be processed by one person. The DNA yield is greater (60 µg per 50-100 µg of fresh leaf tissue) than that obtained from the micro-prep method (50 mg from 5 g of fresh leaf tissue). High quality DNA was obtained and used successfully for restriction endonuclease digestion and polymerase chain reaction amplifications using the mini-prep CTAB method.

Epipelic and Epilithic Algae of Küçükgöl Lake (Gümüşhane-Turkey)

Abstract: The epipelic and epilithic algae of Kucukgol Lake were studied between June and September 2002. Fifty-five taxa (26 belonging to Bacillariophyta, 23 to Chlorophyta, 3 to Cyanophyta and 3 to Euglenophyta) were determined. Closterium lunula var. biconvexum, Cosmarium asphaerosporum var. strigosum, C. garrolense, C. rectangulare, Euastrum ansatum var. dideltiforme, E. denticulatum and E. pseudotuddalense are new records for the algal flora of Turkey.

Competitive Abilities of the Entomopathogenic Nematodes Steinernema feltiae and Heterorhabditis bacteriophora in the Same Host at Different Temperatures

Abstract: The effectiveness of Turkish strains of the entomopathogenic nematodes Steinernema feltiae and Heterorhabditis bacteriophora on the last instar larvae of Tenebrio molitor were investigated. Mortality rates of T. molitor larvae caused by each nematode species alone (experiment I) were determined. Then, with the same method, the effectiveness of each species over the other in competition was examined (experiment II). Both experiments were conducted in sterilesand at 12, 18 and 25 iC for 5 days. While in experiment I the efficiency of the species was determined to be 52.5% for H. bacteriophora and 85% for S. feltiae at 12 iC, 93.5% and 95.6% at 18 iC for H. bacteriophora and S. feltiae, respectively, and 97.5% at 25 iC for both species, in experiment II these rates were 3% and 72% at 12 iC; 8% and 85% at 18 iC and 12.5% and 80% at 25 iC for H. bacteriophora and S. feltiae, respectively. The results indicated that S. feltiae was noticeably dominant over H. bacteriophora when both species were applied together at 3 different temperatures.

The Effect of Agricultural Practices on the Spatial Variability of Arbuscular Mycorrhiza Spores

Abstract: The main objective of this paper is to assess the spatial variability of arbuscular mycorrhizal (AM) spore numbers in following two contrasting soil uses. Adjacent plots, one irrigated farmland and the other dry farmland, were marked on a transect (300 m long), with 10-m spacing. Soil samples were collected at 0—30 and 30—60 cm depth and were then analyzed for AM spore numbers and some other soil properties. The analytical results were submitted to different kinds of analysis: classical statistical and geostatistical analysis which showed that coefficient of variations (CV's) and standard deviations for spore numbers in both farmlands were considerably low. Variations of spore numbers in irrigated farmland was lower than those in dry farmland. The soils of irrigated farmland was found to be much more homogeneous than the adjacent dry farmland soil. The results showed that in both farmland, CV's of spores numbers in topsoil horizon were lower than those of subsoil horizon. The pattern of spatial variability of this soil property was found to be different for the two lands. Spore numbers of AM fungi in topsoil and subsoil of irrigated farmland exhibited spatial dependence at the sampled scale and their experimental semivariograms were adjusted to a spherical and linear model respectively. However these data for dry farmland did not exhibit spatial dependence.

Incompatibility Alleles Expressed in Pollen of Turkish Hazelnut Cultivars

Abstract: Sphorophytic pollen-stigma incompatibility is a characteristic of the genus Corylus. Incompatibility alleles expressed in the pollen of Turkish hazelnut cultivars were identified. Cultivars were selected from the field collection at Giresun, and were used as the pollen parents. Tester plants, whose S-alleles were known, were located in Ankara and Corvallis. Compatible crosses produced masses of long and parallel tubes while incompatible crosses produced very short tubes that often curved or ended with a pronounced bulb. The incompatibility alleles S2, S5, S8, S10, S12, S21 and S24 were identified in the pollen of Turkish cultivars. Pollen of Palaz and Yuvarlak Badem expresses S2, pollen of Fofla, Mincane and Sivri expresses S8, pollen of Kan, Cavcava, Ac› and Kargalak expresses S10, pollen of ‹ncekara, Kal›nkara and Uzunmusa expresses S21, pollen of Yass› Badem expresses S5, pollen of Tombul expresses S12 and pollen of Cak›ldak expresses S24.

Phylogenetic Analysis of Vascular Endothelial Growth Factor Diversity

Abstract: The secreted glycoprotein vascular endothelial growth factor (VEGF) is a potent and specific mitogen for vascular endothelial cells, capable of stimulating angiogenesis during embryonic development and tumor formation. Despite intensive research, the functions of several VEGF family members remain a mystery. Insight into their evolutionary relationships could profoundly improve our understanding of why there are so many VEGFs and why we have not been able to dissect their function to our satisfaction. It appears from the presence of several structurally related VEGF proteins that VEGF proteins do have a long divergence history. We investigated the evolution and phylogenetic relationships among VEGF proteins by using the information from the molecular data. Consistent phylogenetic trees were generated with character-based and distance-based methods. Several gene duplication events were detected that led to the formation of today's VEGF diversity.

Identification of Alkaliphilic Bacillus Species Isolated from Lake Van and Its Surroundings by Computerized Analysis of Extracellular Protein Profiles

Abstract: Five reference Bacillus species and 17 native alkaliphilic Bacillus strains, isolated from the water of Lake Van and the soil surrounding it, were identified using phenotypic characteristics and extracellular protein profiles by the method of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). According to the phenotypic characteristics, all the native isolates were Gram-positive, aerobic, endospore-forming, motile, facultatively alkaliphilic Bacillus spp. It was also found that the native alkaliphilic Bacillus isolates were distinguished phenotypically from other Bacillus species. A numerical analysis based on the resulting extracellular protein profiles revealed 5 distinct clusters: native isolates and B. megaterium formed 4 clusters that varied between 69% and 100% similarity, and the other reference Bacillus species formed a cluster with a similarity of above 70%. The research showed that extracellular protein profiles obtained by SDS-PAGE provide an effective approach to the investigation of taxonomic relationships within native alkaliphilic Bacillus isolates and other Bacillus species.

An SEM Study of the Sporulation Process of Pandora Neoaphidis and Neozygites Fresenii

Abstract: The objective of this study was to investigate the development of fungal pathogens in aphid hosts and identify structures characteristic of each fungal species. Aphids infected by Pandora neoaphidis and Neozygites fresenii were incubated for different time periods and examined by SEM. In P. neoaphidis, hyphal bodies concentrated in clumps beneath the cuticle and these formed rosette patterns consisting of a central structure, the developing cystidium, surrounded by developing conidiophores. Rhizoids were the first structure emerging from the P. neoaphidis-killed aphid. Primary spores were formed after 6 h and secondary spores after 10 h of incubation. In N. fresenii, the conidiophores did not group together to form rosette patterns as in P. neoaphidis. Rhizoids were not formed by N. fresenii but infected aphids were held to the leaf by their mouthparts. The primary spores of N. fresenii were formed at 2 h and were generally round or ovoid in shape. These primary conidia formed long slender capillary tubes that produced secondary conidia which were almond shaped and possessed a terminal mucoid hapteron. Saprophytic fungi began to develop on N. fresenii-killed aphids at 24h and by 48 h the whole cadaver was covered. In N. fresenii, spore formation occurred earlier than in P. neoaphidis, but numbers of spores formed by P. neoaphidis were higher than by N. fresenii.

A Gene Expression Study of the TGF-b Signaling Pathway Components in Differentiating PC12 Cells

Abstract: The neuronal differentiation process has been studied in great detail from many aspects. In the PC12 system, NGF was found to induce neuronal differentiation as measured by neurite extensions and neuronal marker expression. This effect was seen to be mainly conducted through the Ras/MAPK pathway; however, additional pathways are suspected to play a significant role in this cellular response. One such pathway is Smad signaling — NGF was previously reported to induce the expression of the TGF-β signal, although the physiological relevance of this was not completely understood. In this study, we analyzed the expression profiles of several TGF-β pathway components, in an attempt to understand the potential role of this pathway in NGF-induced differentiation of PC12 cells. Ozet: Sinir hucresi farkl›laflmas› ifllemi pek cok ac›dan oldukca detayl› olarak cal›fl›lm›flt›r. PC12 sisteminde, NGF'in sinir hucresi farkl›laflmas›n› indukledii hem norit uzant›lar› hem de noronal iflaret anlat›m› olculmek suretiyle gosterilmifltir. Bu etkinin ana olarak Ras/MAPK yola¤› taraf›ndan ortaya c›kar›ld›¤› bilinmekle birlikte, baflka yolaklar›n da bu hucresel tepkide buyuk rol oynad›¤›ndan fluphelenilmektedir. Bu yolaklardan bir tanesi Smad sinyallemesidir — NGF'in daha once TGF-β sinyalinin anlat›m›na sebep olduu gosterilmifltir ancak bunun fizyolojik onemi tam olarak anlafl›lamam›flt›r. Bu cal›flmada biz ceflitli TGF-β yolak elemanlar›n›n anlat›m profillerini inceleyerek bu yola¤›n NGF-induklu PC12 farkl›laflmas›ndaki olas› iflbirliini anlamaya cal›flmaktay›z.

Characterization of the Fungal Pathogen, Entomophaga aulicae (Zygomycetes: Entomophthorales) in Larval Populations of the Green Cloverworm, Plathypena scabra (Lepidoptera: Noctuidae)

Abstract: Entomophaga aulicae was monitored in populations of noctuid lepidopteran pests of soybean during the 2000, 2001, and 2002 growing seasons in South Carolina and infected only Plathypena scabra larvae. No infection by E. aulicae was detected in 2002. Average infection levels of E. aulicae in P. scabra populations in Blackville were 6.0% and 20.0% in 2000 and 2001, respectively. At Clemson, infection was 15.0% and 23.3% for the two sampling weeks in 2000, and infection reached a high of 50.0% in 2001. Pyriform, multinucleate conidia and spherical to slightly oval resting spores were the primary features of this fungus. When conidia were kept in a high humidity for 6-12 hrs they either formed long germ tubes or secondary conidia. Resting spores were formed by budding from parental cells. This study is the first detailed characterization of E. aulicae from P. scabra.

Effect of a-Keto Acids Against H2O2- and NaN3-Induced Mutagenesis in Different Strains of Salmonella Typhimurium

Abstract: The protective effects of a-keto acids on the mutagenicity of H2O2 and NaN3 was investigated in Salmonella typhimurium TA 98, TA 100, TA 102. H2O2 (340 µg/plate) was mutagenic to the strains TA 98 and TA 102 while NaN3 (1.5 µg/plate) was mutagenic only to TA100. The extents of protective effect of pyruvate (220-440 µg/plate) and a-keto glutarate (335-600 µg/plate) against H2O2 were observed to be 37%- 65% in TA 98 and TA 102. a-keto acids were ineffective against NaN3 induced mutagenicity in TA 100. H2O2 (340 µg/plate), in the presence of NaN3 (1.5 µg/plate) and a-keto acids (330-500 µg/plate), was found to be nonmutagenic to the strain TA102. This cross-adaptive response might have been due to the intactness of the DNA repair system in TA 102. The above combination of H2O2, NaN3 and a-keto acids were found to be cytotoxic in TA 98 and TA 100, possibly because these strains carry uvr B mutation causing defect in their DNA repair system.