The Depth-Dependent Mechanical Behavior of Anisotropic Native and Cross-Linked HheG Enzyme Crystals

Enzymes are able to catalyze various specific reactions under mild conditions and can, therefore, be applied in industrial processes. To ensure process profitability, the enzymes must be reusable while ensuring their enzymatic activity. To improve the processability and immobilization of the biocatalyst, the enzymes can be, e.g., crystallized, and the resulting crystals can be cross-linked. These mechanically stable and catalytically active particles are called CLECs (cross-linked enzyme crystals). In this study, the influence of cross-linking on the mechanical and catalytic properties of the halohydrin dehalogenase (HheG) crystals was investigated using the nanoindentation technique. Considering the viscoelastic behavior of protein crystals, a mechanical investigation was performed at different indentation rates. In addition to the hardness, for the first time, depth-dependent fractions of elastic and plastic deformation energies were determined for enzyme crystals. The results showed that the hardness of HheG enzyme crystals are indentation-rate-insensitive and decrease with increases in penetration depth. Our investigation of the fraction of plastic deformation energy indicated anisotropic crystal behavior and higher irreversible deformation for prismatic crystal faces. Due to cross-linking, the fraction of elastic energy of anisotropic crystal faces increased from 8% for basal faces to 68% for prismatic crystal faces. This study demonstrates that mechanically enhanced CLECs have good catalytic activity and are, therefore, suitable for industrial use.

Quality Control Evaluation of an Ayurvedic Herbomineral Compound – Mukkadi Bidalaka

Background: Mukkadi Bidalaka Yoga is a herbomineral compound which is claimed to be effective in Madhumehajanya Timira (Diabetic Retinopathy). In present study, it has been used for Bidalaka Karma.Objective: Present study was designed to watch out on herbal and mineral drugs used in the preparation of Mukkadi Bidalaka Yoga to assess the quality, purity, safety and efficacy of the drug by pharmacognostical (microscopic) study, physicochemical study and chromatographic evaluation. Methods: Pharmacognostical study i.e. morphological characters, organoleptic characters and powder microscopy was done for identification and authentication of all the raw drugs. Physicochemical study and HPTLC of final product were done. Results: Pharmacognostical characters of Mukkadi Bidalaka observed under the microscope were epicarp cells and lignified stone cell of Haritaki, Trichome and lignified scleroids of Bibhitaki, Scleroids, silica deposition of Amalaki, Parenchyma cells and starch grain of Haridra, Prismatic crystal, pitted vessels and fibers of Daruharidra, Cork cells of Nimba, Brown content of Sariva, Trichome, oil globule of Usheera, Stone cells, scleroids, prismatic crystal and fibers of Lodhra, Cork cells , fibers and stone cells of Vata, Parenchyma cells and oil globule of Durva, Border pitted vessels, lignified stone cells oil globule and lignified fiber passing through medullary rays of Chandana, Particles of Girika. Border pitted vessels, lignified fiber, lignified fiber passing through medullary rays of Raktachandana. Pharmaceutical evaluation of Mukkadi Bidalaka Yoga showed results loss on drying at 110C 5.85 % w/w, pH value 6.0, water soluble extract 21.60% w/w, methanol soluble extract 14.28% w/w, Ash value 3% w/w acid insoluble ash 0.39% w/w. High Performance Thin Layer Chromatography result shows 9 spots at 254 nm and 7 spots at 366 nm. Conclusion: Identification and authentication of herbal drug used in the preparation of Mukkadi Bidalaka Yoga was done. Pharmacognostical, physicochemical and HPTLC evaluation of prepared drug has been carried out.

Pharmacognostical and Phytochemical Evaluation of Leaf of Clerodendrum phlomidis Linn. F.

Clerodendrum phlomidis Linn.f. is a large bush or small tree belonging to the family Verbenaceae. The present study deals with the pharmacognostical and phytochemical study of leaf including chromatographic evaluation. Clerodendrum phlomidis Linn.f. leaf is rhomboid ovate, acute at apex crenate-dentate at margin, sub-cordate at base and velvety in texture. Leaf of the plant can be identified microscopically by the presence of hooked trichomes, glandular sessile trichomes, starch grains, oil globules, Anomocytic type of stomata and rhomboidal and prismatic crystal. Preliminary analysis revealed the presence of carbohydrates, steroid, alkaloids, tannin and phenol. HPTLC study of alkaloid showed the presence of two spots in short and three spots in long UV rays. The information generated by this study provides relevant Pharmacognostical and Physico-chemical data needed for proper identification and authentication of leaf of Clerodendrum phlomidis Linn.f.

Occurrence, type and location of calcium oxalate crystals in selected medicinal plants

Crystals in selected medical plants growing naturally in Place palayam reserve forest, Thiruvallur District were studied with Polarised light microscope. Four types of crystals were observed: druses, prismatics, raphide and rosettes crystal. Druses more in cortical parenchyma and ground parenchyma cells in the stem & petiole region. In contrast prismatic, raphide and rosettes present in cortical, ground, axial and phloem parenchyma in the roots and stems. The Preliminary results show the presence of four types of calcium oxalate crystals in the stems, Petiole & roots of 10 Species: Achyranthes aspera, Aerva lanata, Atalantia monophylla, Bridelia Crenulata presence of Druses crystal, Plumeria rubra, Adhatoda zeylanica presence of prismatic crystal, Asparagus racemosus, Monochoria vaginalis presence of raphide crystal and Carica papaya and Carissa spinarum presence of rosette type of crystal. These observations indicate that there is relationship between the distribution of calcium oxalate crystals and the medicinal parts of the plant and supports the view that the presence of calcium oxalate crystals may relate to the adulterants.

Active sites in heterogeneous ice nucleation—the example of K-rich feldspars

Ice formation on aerosol particles is a process of crucial importance to Earth’s climate and the environmental sciences, but it is not understood at the molecular level. This is partly because the nature of active sites, local surface features where ice growth commences, is still unclear. Here we report direct electron-microscopic observations of deposition growth of aligned ice crystals on feldspar, an atmospherically important component of mineral dust. Our molecular-scale computer simulations indicate that this alignment arises from the preferential nucleation of prismatic crystal planes of ice on high-energy (100) surface planes of feldspar. The microscopic patches of (100) surface, exposed at surface defects such as steps, cracks, and cavities, are thought to be responsible for the high ice nucleation efficacy of potassium (K)–feldspar particles.

Morphology of L-Alanine Crystal, Associated with its Interaction with Glycine Additive: A Molecular Modelling and Experimental Study

. In this paper, L-alanine crystal was crystallized in the presence and absence of glycine additive using slow evaporation method, in association with a simulation technique using ab-initio quantum mechanical method used to predict the crystal morphology of L-alanine. Comparison between the experimental and simulated lattice energies have shown a good agreement with the 8% error, thus validating the set of force field and the partial atomic charges used. Attachment energy method used by the simulation to predict the morphology of L-alanine crystal, revealed a prismatic crystal morphology bounded with 10 dominant faces: (110), ( 0), ( 10), (1 0), (020), (0 0) (011), (0 ), (0 1) and (01 ), which is in good agreement with the experimental morphology. Crystallization of L-alanine in the presence of glycine in the solution also resulted in prismatic crystal morphology, but elongated in the z-axis direction. This result was further explained by intermolecular bonding analysis of glycine on the morphological faces of L-alanine crystal, which suggested that glycine was preferentially adsorbed on the (0 ) and (1 0) faces of L-alanine crystal morphology.

Revision and evaluation of the systematic affinity of the calcitarch genusPithonellabased on exquisitely preserved Turonian material from Tanzania

Extraordinarily well-preserved pithonellid microfossils (calcitarchs, “calcispheres”) from the Turonian (upper Cretaceous) of Tanzania reveal previously unknown morphological traits, crystallographic patterns, and chemical signatures, providing new insight to this enigmatic group of microfossils. Using combined transmitted-reflected light microscopy, scanning electron microscope imagery, electron microprobe elemental analysis and stable isotope geochemistry, the present study reveals four new aspects of the genusPithonella, notably, the following. An affinity with cyst-forming organisms, potentially the dinoflagellates, is indicated by the presence of a hatch opening and corresponding operculum. The pristine outer wall architecture consists of thin, smooth shingle-shaped plates with regular rows of slit-shaped pores and an apical sub-angular or circular pore. This primary surface pattern is significantly different from previous descriptions of an outer wall consisting of “parquet-shaped” prismatic crystal rows; this latter surface pattern is formed by secondary overgrowth. The crystallographic pattern of the inner wall is crypto-crystalline. Unaltered pithonellids reveal a calcite chemistry characterized by comparably high Mg-contents, relatively enriched stable carbon isotope values, and stable oxygen values indicating a surface water habitat. Based on these previously unseen traits, the diagnosis of the genusPithonellais emended. A new species,Pithonella diconica, is described from the lower-middle Turonian sediments of Tanzania.

Mushroom elbaite from the Kat Chay mine, Momeik, near Mogok, Myanmar: II. Zoning and crystal growth

A variety of mushroom tourmaline from the Kat Chay mine, Momeik, near Mogok, Shan state, Myanmar, consists of a black-to-grey single-crystal core from which a single prismatic crystal reaches to the edge of the mushroom, forming a slight protuberance. The rest of the mushroom (∼50% by volume) consists of extremely acicular sub-parallel crystals that diverge toward the edge of the mushroom. The acicular crystals are dominantly colourless to white, with a continuous black zone (2 mm across) near the edge, and pale pink outside the black zone. The composition varies from ∼Na0.75Ca0.05(Li0.80Al0.70Fe1.10.Mn0.30Ti0.10)Al6Si6(B03)3O18(OH)3(OH,F) at the base of the mushroom to ∼Na0.60Ca0.06(Li1.00Al1.98Fe0.02)Al6(Si5.35B0.65)(BO3)3O18(OH)3(OH,F) close to the edge at the top of the mushroom. The principal substitutions are: (1) YLi + YAl -> yFe* + yFe* and (2) TB + yAl -> Si + yFe*, but there are five other minor substitutions that are also operative. There are six significant compositional discontinuities at textural boundaries in the mushroom, suggesting that the changes in habit are driven in part by changes in external variables such as T and P, plus possible involvement of new fluid phases.