Light microscopy of Pakistani Berberis leaf cuticles and its taxonomic implications

Taxonomy of the genus Berberis is quite complex, due to overlapping morphological characters, making it very difficult to differentiate the species within the genus. In order to resolve this taxonomic complexity, the foliar anatomy of 10 Berberis L. species was carried out, for the first time from Pakistan, using light microscopy (LM). Significant variation in terms of epidermal cells shape, size, cell wall pattern, and stomata type was observed. B. baluchistanica has the largest epidermal cells, Adaxial: length = 45–(53.9 ± 3.6)–62.5 μm; and width = 22.5–(26.3 ± 1.3)–30 μm; Abaxial: length = 37.5–(43.25 ± 2.5)–50 μm; and width = 20–(22.6 ± 0.8)–25. The highest number of stomata was observed in B. glaucocarpa as 62 on the abaxial surface while the lowest number of stomata was recorded in B. baluchistanica as 8 on the adaxial surface. Of 10 investigated species, 6 possess anomocytic type stomata, while 2 species that is, B. aitchisonii and B. parkeriana have both anomocytic and anisocytic stomata while B. baluchistanica and B. calliobotrys have only paracytic type stomata. The highest number of cells per unit area was present on the adaxial surface of B. calliobotrys ranging from 245–(252.4)–260 followed by B. parkeriana with 209–(227.8)–250 on the abaxial surface. Stomatal index (SI) also varied considerably and was the lowest (2.6) percentage in B. baluchistanica and highest (31.9) percentage in B. kunawurensis. A taxonomic key based on micro‐morphological characters is provided for species identification.     

Discovery of Five New Ethylene-Forming Enzymes for Clean Production of Ethylene in E. coli

Ethylene is an essential platform chemical with a conjugated double bond, which can produce many secondary chemical products through copolymerisation. At present, ethylene production is mainly from petroleum fractionation and cracking, which are unsustainable in the long term, and harmful to our environment. Therefore, a hot research field is seeking a cleaner method for ethylene production. Based on the model ethylene-forming enzyme (Efe) {"type":"entrez-protein","attrs":{"text":"AAD16440.1","term_id":"4323597","term_text":"AAD16440.1"}}AAD16440.1 (6vp4.1.A) from Pseudomonas syringae pv. phaseolicol, we evaluated five putative Efe protein sequences using the data derived from phylogenetic analyses and the conservation of their catalytic structures. Then, pBAD expression frameworks were constructed, and relevant enzymes were expressed in E. coli BL21. Finally, enzymatic activity in vitro and in vivo was detected to demonstrate their catalytic activity. Our results show that the activity in vitro measured by the conversion of α-ketoglutarate was from 0.21–0.72 μmol ethylene/mg/min, which varied across the temperatures. In cells, the activity of the new Efes was 12.28–147.43 μmol/gDCW/h (DCW, dry cellular weight). Both results prove that all the five putative Efes could produce ethylene.     

Synthesis of Clay/Poly (styrene/2-ethylhexyl acrylate) Nanocomposite Latexes via Emulsion Polymerization

Silicon - In this research, nanocomposite latex based on polystyrene-co-2-ethylhexyl acrylate with layered silicate was synthesized by emulsion polymerization procedure. For increasing...     

Environment-Friendly Synergistic Abiotic Stress for Enhancing the Yield of Lipids from Oleaginous Yeasts

The microbial lipids isolated from oleaginous yeasts are a potential alternative to tree borne oils. There is a need to optimize and enhance the production of lipid by various stress approaches. In the present study, yeasts are subjected to physico-chemical stresses, and growth, as well as lipid concentration at different time intervals are monitored. It is found that the nanoparticles (NP) such as Ag-NP and Zn-NP have an inhibitory effect on yeast growth. Most yeast strains show an increase in growth and lipid accumulation when ionic liquid (1-ethyl-3-methylimidazolium acetate) ([EMIM][OAc]) and table salt (NaCl) stress are applied. Lipid is chemically characterized using gas chromatography furnished with flame ionization detector (GC-FID), GC/MS, and NMR techniques. It contains a higher percentage of saturated fatty acids (SFA: 74.3%), monounsaturated fatty acids (19.1%) with low amounts of polyunsaturated fatty acids (1.9%). The thermo-stability study reveals that the lipid have higher volatility (380–410 °C) as closely compared with coconut oil, and much lower with respect to the winged bean oil (430–470 °C). The melting point of the lipids (37 °C) is determined through differential scanning calorimetry (DSC). The DSC and physico-chemical properties are supported that the yeast lipids may use as a cocoa-butter substitute. Production of lipid under NaCl stress (200 × 10⁻³ m ) is more than 60.4% higher as compared to the control. However, the combined stress effect of NaCl (200 × 10⁻³ m ) and 15 × 10⁻³ m of [EMIM][OAc] results in more than 96.4% yield of lipid. The exchange of inorganic and organic ions in combined treatment forces the microbial cells to accumulate more amounts of lipid, which may form a lipid-emulsion layer to protect the cell from osmosis. It is interestingly observed that the stress cells shift the flux to accumulate a significantly improved percentage of SFA, which could be provided better protection cover due to its expanded structure, less reactive characteristics, and completely insoluble nature in ionic-aqueous solvent. Practical applications: Oleaginous yeast is multiplied in a very limited space, and easily scalable for sustainable production of lipid to meet its commercial demand. This novel approach for enhancing the yield of lipid with the application of synergistic stress in between NaCl and the green solvent (ionic liquid) is being reported for the first time. This lipid has potential alternative applications as cocoa-butter.     

P75 and S100 gene expression induced by cell-imprinted substrate and beta-carotene to nerve tissue engineering

Here we aimed to differentiate adipose derived stem cells (ADSCs) to Schwann cells (SCs), as one of the major and instrumental cell sources in nerve regeneration, by synergistic application of imprinting method and β-carotene. Accordingly, the topography of Schwann cells was imprinted on poly dimethyl siloxane (PDMS) substrates via mold casting and human ADSCs seeded on substrates; moreover, β-carotene was added to induce hADSCs differentiation. Physiochemical evaluations of PDMS by FTIR spectra presented its silicon-methyl bond (Si CH₃) at 1260 cm⁻¹. Morphology analysis by crystal violet, picrosirus red staining, and SEM images illustrated that MSCs seeded on imprinted substrates have formed SC-like morphology. Furthermore, according to q-PCR and ICC evaluations, SCs specific markers; S100 and P75 in addition of 5 μl β-carotene (BC) were upregulated (p-value<0.001). Also, the expression was detected on the imprinted surfaces without β-carotene to a lesser degree. Our study revealed that Schwann cell imprinted substrates can mimic the morphology and topography of SCs and induce differentiation signals in mesenchymal stem cells (MSCs). In addition, the potency of β-carotene as an organic substance in boosting and stimulating the neural differentiation was demonstrated. Relevantly, the reports have confirmed the synergistic pivotal roles of β-carotene and patterned surfaces in directing MSCs into SC-like cells differentiation without applying expensive and less safe chemical growth factors.     

Comparative light and scanning electron microscopy in authentication of adulterated traded medicinal plants

The medicinal plants are utilized globally considering the cheap and chemical free source, but their correct identification and authentication is prerequisite for safety and efficacy of plant‐based medicines. The present study encompassed traded medicinal plants (16) with high therapeutic value from diverse families like Brassicaceae, Berberidaceae, Malvaceae, Salicaceae, Myrtaceae, Papilionaceae, Ascelpiadaceae, Colchicaceae, Violaceae, and Vitaceae for detailed microscopic study of characters that is, morphology, pollen shape and sizes, P/E ratio, pore length and width, spine length, colpi dimensions, and exine sculpture pattern. The plants showed noteworthy differences in microscopy of Wattakaka volubilis having pollinia, translator and corpusculum like structures while pores were visible in Colchicum luteum, Alcea rosea, and Hibiscus syriacus. The spines were observed in Centipeda minima, A. rosea, and H. syriacus being dimorphic spines in A. rosea and monomorphic in H. syriacus. The exine sculpturing pattern was reticulate in mostly studied plants however distinctive exine pattern was noted in Berberis aristata and Berberis lyceum. The highest polar diameter, equatorial diameter and exine thickness among studied plants were observed in H. syriacus (161 μm), C. luteum (50 μm) and Vitis jacquemontii (1.10), respectively. Thus, microscopy of medicinal plants in addition to other taxonomic evidence offers a supportive skill in authentication, consequently utilization by local consumers and pharmaceutical industries.     

Band‐Gap Engineering and Enhanced Photocatalytic Activity of Sm and Mn Doped BiFeO3 Nanoparticles

Bi_1‐xSm_xFe_1‐yMn_yO₃ (BSFMO, x = 0.0, 0.05; y = 0.0, 0.05, 0.10, 0.15, 0.20, 0.25) nanoparticles were synthesized by using double solvent sol–gel method. Photocatalytic activity was investigated under UV and visible‐light illumination. The structural, morphological, and optical properties were analyzed by X‐ray diffraction, scanning electron microscopy, and UV‐vis spectroscopy respectively. The crystallite size of BiFeO₃ (BFO) decreases from (57.3–17.2 nm) with the increase in Sm and Mn‐doping concentration. The surface morphology shows that the pure and Sm‐doped BFO nanoparticles are irregular in shape but changes to spherical shape after Mn‐doping up to 25%. The band‐gap engineering of BFO nanoparticles is achieved by co‐doping of Sm and Mn. The band‐gap of BFO could be tuned successfully from 2.08–1.45 eV, which may be due to the distortion induced in Fe‐O octahedron and the rearrangement of molecular orbitals. These results give rise to enhanced photocatalytic activity by degradation of organic dyes (MB, CR, and MV) under the visible‐light illumination.     

Fabrication of metallic Cd multifarious prismatic microcrystals (CMPMCs) under NH3 gas ambient

We report here highly dense and pure metallic cadmium (Cd) multifarious prismatic microcrystals (CMPMCs) fabricated by thermal decomposition of cadmium oxide (CdO) powder at 700 °C for 60 min under NH₃ gas ambient inside horizontal tube furnace. CMPMCs were observed to be 1-1.5 μm in size with interesting morphologies of various cross sections such as triangular, trapezoidal, pentagonal and hexagonal etc. having solid, hollow/semi-hollow appearances. The as-synthesized CMPMCS were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and selected area electron diffraction (SAED). Room temperature photoluminescence (PL) spectrum for Cd metal microcrystals exhibited a prominent emission band at 365 along with a shoulder peak at 404 nm. The UV main emission band is ascribed to radiative recombination of the electrons in the s, p conduction band near the Fermi surface and holes in the d bands generated under xenon light excitation whereas shoulder peak may be owing to surface oxidation effects or induced defects. This study shows the potential of CMPMCs for applications in optical devices. Based on vapour-solid (VS) process, growth mechanism for the formation of CMPMCs is also proposed and discussed briefly.     

Implementation of IEEE 802.16e Standard on Xilinx ZC706: A C-RAN Prototype

Wireless Personal Communications - In this paper, we propose an architecture to implement IEEE 802.16e transmitter and receiver physical (PHY) layer on field programmable gate arrays. Several...     

Investigation of some oleochemicals as green inhibitors on mild steel corrosion in sulfuric acid

The inhibitive effect of four oleo chemicals (namely; 2-Pentadecyl-1,3-imidazoline (PDI), 2-Undecyl-1,3-imidazoline (UDI), 2-Heptadecyl-1,3-imidazoline (HDI), 2-Nonyl-1,3-imidazoline (NI)), regarded as green inhibitors, were studied for the corrosion protection of mild steel in 0.5 M H₂SO₄. The methods employed were weight loss, potentiodynamic polarization and electrochemical impedance techniques. Scanning electron microscopy (SEM) was carried out on the inhibited and uninhibited metal samples to characterize the surface. The purity of synthesized inhibitors was checked by FT-IR and NMR studies. The inhibition efficiency increased with increase in inhibitor concentration, immersion time and decreased with increase in solution temperature. No significant change in IE values was observed with increase in acid concentration. The best performance was obtained for UDI possessing 96.2% inhibition efficiency at 500 ppm concentration. The adsorption of the compounds on the mild steel surface in the presence of sulfuric acid obeyed Langmuir’s adsorption isotherm. The values obtained for free energy of adsorption and heats of adsorption suggest physical adsorption. The addition of inhibitor decreased the entropy of activation suggesting that the inhibitors are more orderly arranged along the mild steel surface. The potentiodynamic polarization data indicate mixed control. The electrochemical impedance study further confirms the formation of a protective layer on the mild steel surface through the inhibitor adsorption.