Progress in Biological Sciences
Volume:5 Issue: 2, Summer and Autumn 2015

Curcumin is a hydrophobic polyphenol extracted from the plant curcuma longa with established anticancer properties. However, curcumin benefits have been impaired by its very low water solubility, low absorption, rapid metabolism and clearance from the body. Recently, nanotechnology promises to be helpful in development of drugs delivery systems by recent advances in macromolecular design of nanocarriers. In this review, we present the novel generation of nano-vehicles termed dendrosomes which are readily synthesized from esterification of oleic acid and polyethylene glycol residues. Dendrosomes efficiently encapsulate curcumin in a spherical micellar or polymersome structures which leads to increase aqueous solubility of this hydrophobic agent and higher bioavailability of curcumin. Anticancer potency of this nanoformulation was confirmed in different mouse and human cancer cells including fibrosarcoma, colon, glioblastoma, bladder, gastric, breast and hepatocellular carcinoma in vitro and vivo. It has also demonstrated that this nano preparation has no cytotoxicity effects on normal cells. Finally, these results introduce dendrosomal curcumin as potent anti-tumor agent although further clinical examinations are needed.

Screening of microorganisms for the production of novel antibiotics has been intensively pursued for many years by scientists. Actinomycetes have the capability to synthesize many different antibiotics. A total of 69 actinomycete isolates were recovered from soil samples collected from Alborz Province. Selected colonies (rough, chalky) of actinomycetes were purified. All screened isolates were identified morphologically and physiologically. And all of them belong to the Streptomyces genus. These were then assessed for their antibacterial activity against pathogenic bacteria. Four pathogenic test strains were used in this study including Staphylococcus aureus ATCC 6538, Bacillus subtilis ATTC 6633, Klebsiella pneumoniae ATTC 10031, and Escherichia coli ATCC 29998. Determination of antibacterial activities of isolated actinomycetes performed by using modified spektra-plak method and Mueller Hinton agar (Oxoid) plates. Antagonism was detected by formation of inhibition zone. Results of the study indicated that 12 isolates were active against S. aureus, 15 isolates against B. subtilis, six isolate against K. pneumonia, and four isolate were active against E. coli.

Lilium ledebourii (Baker) Boiss. (Liliaceae) is a critically endangered lily species native to northern Iran, where it is protected by law. In order to develop a cost effective method for largescale propagation, the effects of three culture systems (solid, liquid and temporary immersion) and two types of cytokinins [6-Benzyladenine (BA) and Thidiazuron (TDZ)] were studied on the in vitro plant regeneration of L. ledebourii. To establish the protocol, we used in vitro regenerated bulblets obtained from bulb scale segments that were cultured on solid Murashige and Skoog (MS) media as starting material. The bulblet microscale transverse thin cell layers were cultured on MS solid medium containing 3% sucrose and different combinations of plant growth regulators. Choice of both, the culture system and the type of cytokinin, affected the differentiation of explants. Two types of calli formed on explants: type I callus was embryogenic, while type II callus was shoot organogenesis. The highest percentage 94%) of embryogenic callus was obtained when calli were transferred on MS solid media supplemented with 0.54 μM α-Naphthaleneacetic acid (NAA) and 0.44 μM BA. In addition, it was also observed that the use of temporary immersion bioreactor resulted in a significantly lower amount of shoot organogenesis rather than solid culture systems. Seventy percent of the plantlets were successfully acclimatized to ex–vitro conditions and were phenotypically similar to the mother plants.

In the present study, a field study was performed on some herbaceous plants growing in the southeast of Ahvaz, where some metal producing industries are active. The aim of this study was to investigate and compare manganese (Mn) and zinc (Zn) accumulation in seven dominant herbaceous plants in this area. Plant samples were collected randomly. Associated soils were sampled from the same sites next to the root of individual plants. The metals concentration in the soil and the plant samples were determined by flame atomic absorption spectrometry. Highest Mn and Zn concentrations were observed in the shoots of Halocnemum strobilaceum, Taraxacum kotschyi, Malva parviflora, and Solanum nigrum. Moreover, elevated accumulation of Mn was found in the roots of Lolium temulentum, and Convolvulus arvensis. Regarding to defined standards for phytoremediation purposes, studied plants could not be classified as hyperaccumulators, at least under field conditions. Nevertheless, based on accounted bioconcentration and translocation factors, it seems that the majority of investigated plants have the metals accumulation capacity in shoot parts.

The mouths of some bony and cartilaginous fishes are located in the anterior part of their bodies, with a slight variation in sharks, which have theirs located in the abdominal part. This variation is evolutionary over time. The force exerted by the jaws of sharks in order to dismember their prey can be examined from two origins:. The determined force exerted by teeth and muscles and the force as a result of torque arm through jaw distance. Although sharks apply less force compared to crocodile, their sharp teeth and mouth position provides much stronger effect. Moreover, several species are characterized with heavier upper jaw and this enhances the power. A mouth located in the anterior part of the body would have less force exerted. On the contrary, human jaw is shorter, which applies much more force. This paper relates the prebranchial length and power with preying strength. According to this survey, a couple of predators were considered in terms of their mouth position, as well as different kind of feeding and ecological characteristics. Morphological data on several sharks were extracted and evaluated by MATLAB software to prove the following deductive hypothesis. The more the support distance (prebranchial length) to concentrated force was, the stronger the shark preyed on animals. The amount of torque had significant relationship with the lever distance and concentrated force. Besides, several formulas have been recommended to estimate the bite force and torque based on morphological characteristics.

Bioleaching is the extraction of metals from their ores through the use of microorganisms. In this process, the use of native bacteria leads to achieve more yields of metals. So, in the present study, native sulfur-oxidizing bacterium in potentiality of uranium extraction was isolated from Ghachin mine in Iran and identified by partial gene sequencing. For this purpose, the water samples were collected from Ghachin mine and cultivated in Starkey medium. In following, the isolate was inoculated into individual Starkey plates and incubated until the colonies indicating the purified bacterium appeared. Then, the identification was carried out based on phenotypic characteristics and 16s rDNA sequencing. After that, bioleaching of uranium experiments carried out using uranium ore at 2.5 and 5% pulp densities. The result showed that after 15 days of incubation, the bacteria in the fresh samples was grown. Following 5-7 days of the plate's incubation, we obtained the single purified colonies of the bacteria. On the basis of 16s rDNA nucleotide sequencing, the bacteria showed 99.71% similarity to A. thiooxidans ATCC 19377. Besides, the bioleaching experiments indicated that the bacterium is capable of uranium extraction in 2.5 and 5% pulp densities during 3 and 5 days. In conclusion, in this study, for the first time, we isolated the native sulfur-oxidizing bacterium capable of uranium extraction, from uranium mine of Gachin in Bandar Abbas, Iran.

The purpose of this study was to examine the acute and sub-acute effects of diazinon on histopathological parameters of liver tissue and blood level of hepatic enzymes of male common frog (Rana ridibunda). Frogs were assigned to 9 groups (n=8, meaning 8 frogs in each group): control and treatment groups with 30, 60, 90 and 120 μg/L diazinon in water for one day or one week. Hepatic enzymes containing alanine transaminase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were measured using biochemical kit. All ALP values were significantly different between the control group and one-day and one-week diazinon exposed groups. Hepatocyte changes were observed only for diazinon concentrations greater than 60 μl after one week. The most important characteristics of the affected cells were hyperplasia and chromatin formation. Results show that sub-lethal concentrations of diazinon have an increasing effect on the blood level of hepatic enzymes, which probably indicated the detoxification response of liver on the basis of diazinon sub-lethal effect model.

Effects of salinity and drought on growth, contents of proline, malondialdehyde (MDA), protein and activity of antioxidative enzymes were studied in two Trigonella species. Seeds and explants of T. foenum-graecum and T. aphanoneura were grown on Murashige and Skoog medium (MS) complemented with iso-osmotic concentrations of NaCl (0, 100, 150 mM) and mannitol (0, 180, 275 mM). Growth and relative water content (RWC) of seedlings and calli decreased by increasing of salinity and drought in both species. In contrast to that of calli, proline and protein contents increased in seedlings of both species under both stresses. The increase of proline content in seedlings of T. aphanoneura was higher than that of T. foenumgraecum under NaCl stress. MDA content in seedlings of T. aphanoneura was higher than that of T. foenum-graecum and increased in both species under salinity. Among antioxidative enzymes, catalase (CAT) activity increased continuously in seedlings of T. aphanoneura comparing to that of T. foenum-graecum. Similar increasing trends were obtained regarding CAT activities in calli of both species under both stresses. Increase in activities of SOD, CAT and POX was observed in calli of both species under stress. It seems that undifferentiated calli respond more regularly to both stresses. Finally, higher proline content and lower amount of MDA could be considered as criteria for higher tolerance of T. foenum-graecum seedlings against osmotic stresses.

The present study reports the chromosome number and meiotic behaviour of 14 populations belonging to four taxa of Anchusa subgenus Buglossum Gusul. from Iran. All populations showed the chromosome number 2n= 4x= 32. It is the first meiotic study for A. subg. Buglossum. We discuss some habit form and evolutionary aspect in the light of cytogenetic data. The origin of polyploidy (auto-allopolyploidy) were also surveyed. As the result of the present study and reviewing the chromosome numbers in Anchusa subg. Buglossum and A. subg. Buglossoides Gusul. in Iran, it can be concluded that polyploidy is the major force modeling the chromosome evolution within these subgenera. Almost all the studied taxa displayed regular bivalent pairing and chromosome segregation at meiosis. However, some meiotic abnormalities observed in different taxa are discussed here.

The ingested nitrates sourced from tap water, food, chemicals and pharmaceuticals are converted to nitrites in the body surfaces by bacteria and then, the nitrite ions can lead the structural changing in hemoglobin. In the present work, aggregation of the purified hemoglobin in adult (HbA) and in fetus or newborn (HbF) in the presence of nitrite ions were studied. Hemoglobin aggregation was performed chemically in the presence of 10 mg/l nitrite ions and examined by UV-Vis spectrophotometer at 360 nm wavelength. The extrinsic fluorimetric measurements indicated that repulsive electrostatic interaction between nitrite anions and negative charged groups of both types of HbA and HbF molecules leads to expose the hydrophobic patch of the protein molecules. Moreover, the α-helix to β-strand transition in both types of hemoglobins shown by circular dichroism support aggregation process among this protein. However, at natural pH, the protonated amino group of Gly in HbF tends to bind to nitrite anions more than the unprotonated forms of Val residue in HbA. The drastic slop of aggregation plot and shorter lag time of HbF relative to HbA demonstrated more aggregation of former protein.

Saffron is the dried stigmas of Crocus sativus L., a member of the Iridaceae family which is propagated by means of corms. Corms are faced with many stresses in soil. Therefore, it is important to reduce these stresses and improve the quantity of saffron production. Biotic and abiotic stresses disrupt the metabolic balance of cells; thereby, resulting in accumulation of reactive oxygen species (ROS) which cause oxidative damage. In this study, the effect of soil electrical conductivity (EC) on biochemical indicators of corms, the percentages of callus formation and stigma-like structures (SLSs) on calli were investigated. In order to obtain calli and SLSs, immature style explants from floral buds of corms were collected from three regions (Shahroud, Mardabad and Torbat Heydarieh) and used for tissue culture. Style explants were separated first from the immature floral buds, then sterilized and used for tissue culture. Biochemical analysis of calli with SLSs including malondialdehyde (MDA) and proline contents, antioxidant enzymes activities and polysaccharides and reducing sugars contents were investigated and compared. Moreover, sodium and potassium ions content and EC of soils of the three regions were investigated. The results indicated that corms from Shahroud with the highest level of EC soil showed more imposed stress than that from Torbat Heidariye and Mardabad but the calli percentage and number of SLSs of Mardabad’s were higher than those of the other two respectively. In this study, a close relationship between soil EC and in vitro production of saffron with a short glance on epigenetic modification was postulated.

The aim of this study was to optimize protease production using a novel Bacillus sp. ZR-5 strain isolated from the soil, and evaluate its application in detergent industry. The proteolytic activity of the strain was demonstrated using gelatin hydrolysis screening test. Protease production optimization was carried out using a two-step approach: a conventional method in order to identify the best carbon and nitrogen sources followed by the application of response surface methodology (RSM) to optimize the factors, which include temperature, pH and incubation time. Glucose or fructose (5 g/L), wheat bran (5 g/L), temperatures of 25 and 55°C, pH 10.0 and an approximate incubation time of 44 h, were determined as the optimal conditions according to optimization processes. Validation tests were carried out under these conditions and the results were in good agreement with RSM predicted data. The in-gel activity (zymogram) test showed two hydrolytic zones with 66.2 and 36.5 kDa molecular weight on the casein containing polyacrylamide gel. The high compatibility in the presence of detergent powder and washing performance test suggested that the crude enzyme could be an appropriate choice as a detergent additive in detergent industries.