Synthesis and Characterization of a New Norfloxacin/Resorcinol Cocrystal with Enhanced Solubility and Dissolution Profile

A new cocrystal of Norfloxacin, a poorly soluble fluoroquinolone antibiotic, has been synthetized by a solvent-mediated transformation experiment in toluene, using resorcinol as a coformer. The new cocrystal exists in both anhydrous and monohydrate forms with the same (1:1) Norfloxacin/resorcinol stoichiometry. The solubility of Norfloxacin and the hydrated cocrystal were determined by the shake-flask method. While Norfloxacin has a solubility of 0.32 ± 0.02 mg/mL, the cocrystal has a solubility of 2.64 ± 0.39 mg/mL, approximately 10-fold higher. The dissolution rate was tested at four biorelevant pH levels of the gastrointestinal tract: 2.0, 4.0, 5.5, and 7.4. In a first set of comparative tests, the dissolution rate of Norfloxacin and the cocrystal was determined separately at each pH value. Both solid forms showed the highest dissolution rate at pH 2.0, where Norfloxacin is totally protonated. Then, the dissolution rate decreases as pH increases. In a second set of experiments, the dissolution of the cocrystal was evaluated by a unique dissolution test, in which the pH dynamically changed from 2.0 to 7.4, stepping 30 min at each of the four biorelevant pH values. Results were quite different in this case, since dissolution at pH 2 affects the behavior of Norfloxacin at the rest of the pH values.

Event-specific qualitative polymerase chain reaction analysis for two T-DNA copies in genetically modified orange Petunia

In 2017, various orange coloured petunia on the market turned out to be genetically modified (GM) without an official authorization for commercialization. Sequence analysis suggested these undeclared plants most probably originated from a plant transformation experiment performed in the 1980s. For a deeper understanding how GM petunia entered classical breeding programmes worldwide, and whether they originated from a single source or not, we undertook a molecular genetic characterization of the T-DNA integration sites in different GM petunia cultivars and breeding lines. By means of genome walking, we isolated different T-DNA sequences, which are located at the junctions between the T-DNA(s) and the petunia DNA. Based on the results obtained we conclude that there are at least two T-DNA copies of different lengths. This is supported by Southern blot analysis. For T-DNA1, the 3′-junction sequence was isolated, whereas the 5′-junction remained unclear. In contrast, for T-DNA2, the 5′-junction sequence was isolated, whereas the sequence isolated from the 3′-region consists only of T-DNA, but did not include the junction from the T-DNA to the petunia DNA. We developed primers for event-specific PCRs and screened a set of three orange GM petunia cultivars and 126 GM offspring from a commercial breeding program. We show that both T-DNA copies are present in all our tested GM petunia samples, which underpins the assumption of a single transgenic origin of the undeclared GM petunia. Most likely, the two T-DNAs are integrated in close proximity into the petunia genome.

Transformasi Gen Antisens ACC Oksidase pada Pepaya dengan Teknik Penembakan Partikel

Papaya (Carica papaya L.) is a climacteric fruit that exhibit a<br />very fast ripening rate. Ethylene controls the ripening event<br />in the papaya fruit. 1-aminocyclopropane-1-carbocxylic acid<br />(ACC) oxidase gene encodes a specific enzyme for ethylene<br />biosynthesis. The gene had become a target for manipulation<br />to make a gene construct of an antisense ACC oxidase<br />to regenerate transgenic papaya that has a characteristic of<br />delayed ripening. The objective of the experiment is to engineer transgenic papaya that has a delayed ripening characteristic by transforming papaya with the antisense ACC oxidase gene through particle bombardment technique. The immature embryos of papaya variety Burung<br />were used for the explants. Antisense ACC oxidase and reporter (gus) genes were co-transformed to papaya calli. Four hundreds eighteen calli were bombarded by the antisense ACC oxidase gene. The transformation experiment resulted 25 putatives transgenic plants out of fifty plants<br />acclimatized in a greenhouse. Gus gene expression assay observed at 9 days after bombardment showed that the papaya explants bombarded twice at 9 cm shoot distance had 53.3% transformation rate of gus positive and 5.25 blue spots number in average. The results of PCR analysis showed that four out of 25 transgenic putative papaya plants (TR6, TR9, TR20, dan TR24), indicated a positive PCR of the antisense ACC oxidase gene with the amplified fragment DNA size of 800 base pair.

Single-crystal-to-single-crystal transformation of an anion exchangeable dynamic metal–organic framework

A 3D cationic Metal–Organic Framework has been fabricated with a neutral N-donor ligand and Cd(ClO4)2 which shows guest triggered dynamic behaviour at room temperature. This structural dynamism has been demonstrated from the SCSC transformation experiment.

Outdoor Clothing Ecodesign Using Zipper as Functional Transformation Medium

Outdoor clothing may vary multiple styles by means of opening, closing or replacing zipper and display different exterior profiles and functions in order to better satisfy the needs of outdoor activities. Using zipper as the transformation medium in synchronous transformation experiment for outdoor clothing and bag in style and function, this study realizes the perfect combination of practicality, functionality, aesthetics and enjoyment of products, extends the design concept of functional outdoor clothing and gives suggestions on ecological development of outdoor clothing.

Study on Strategy Improvement of Yeast Transformation Experiment Based on ANP Method

Combining with the influential index system of yeast transformation experiment, ANP method was adopted to solve the strategy improvement problem of yeast transformation experiment. Based on conclusion of existed study, the influential index system of yeast transformation experiment is developed combining with the fundamental experiments and interviews of experts in such fields. Then based on ANP theory, comparison of influential factors in the yeast transformation experiments is made, and strategies of improving the experiment are obtained in order to achieve economical goal. Adopting such system and method in the yeast transformation experiment, the number of such experiment could be effectively reduced and thus the cost of the whole experiment, and also the effect of the experiment are good, so the theory and method could be used in the familiar experiment.

Standardization of Protocol for Agrobacteriummediated Transformation in Potato (Solanum tuberosum L.)

The experiment was conducted at the Laboratory of Biotechnology, Biotechnology Division, Bangladesh Agricultural Research Institute, Gazipur- 1701 during July 2007 to June 2008. An efficient and reproducible protocol for the production of transgenic potato plants was developed by inoculating internode explants of potato with Agrobacterium tumefaciens strain LBA4404 carrying a binary vector pBI121 having one reporter gene (gus) and selectable marker gene (nptII) resistant to Kanamycin. The transformation experiment was done by optimizing two important parameters names infection time and cocultivation period. Most of the explants produced shoots within 21 days on 5 mg/l Zeatin riboside (ZR) and 50 mg/l Kanamycin supplemented MS medium without introducing callus. The infected explants produced 8.27 and 6.42 shoots in Asterix and Diamant varieties, respectively within 21 days. Transgenes were confirmed by molecular analysis. DNA from well established rooted plants confirmed nptII positive through PCR analysis. The transformation rates were 28.97 and 24.37% in Asterix and Diamant, respectively. Putative transformed plants of Diamant and Asterix varieties produced roots in ½MS medium supplemented with 50/mg Cefotaxim, 50 mg/l Kanamycin and 0.5 mg/l IBA. DOI: http://dx.doi.org/10.3329/bjar.v37i2.11220 Bangladesh J. Agril. Res. 37(2): 185-194, June 2012

Agrobacterium-mediated Genetic Transformation of Potato (Solanum tuberosum L.) var. Cardinal and Heera

Two potato varieties namely Cardinal and Heera were used in the Agrobacterium-mediated genetic transformation experiment to investigate the genetic transformation ability in the Biotechnology laboratory of the Department of Biotechnology, Bangladesh Agricultural University, Mymensingh, Bangladesh during 2006 to 2007. Agrobacterium tumefaciens strain LBA 4404 having a binary vector pB1121 of 14 KDa containing selectable marker gene npt II (neomycine phosphotransferase II) conferring kanamycin resistance, and the CIPK antisense gene encoding calcineurin B-like protein were used. Leaf and internodes were used as explants. Expression of the transgene (GUS) was confirmed by histochemical analysis. The variety Cardinal was found more suitable for expressing best GUS response (80% GUS positive) over Heera.DOI: http://dx.doi.org/10.3329/agric.v10i1.11068The Agriculturists 2012; 10(1): 81-86