Synthesis and Physicochemical Characteristics of Chitosan Extracted from Pinna deltoides

Chitosan, a naturally produced polysaccharide that has a wide range of uses in biological, pharmacological, industrial, and commercial settings. The pen shell Pinna deltoides is a common species found along the coast of Thondi, and it is often collected as by-catch by fishermen. These species contain a high amount of chitin, which may be converted into chitosan. The goal of this research is to extract chitosan from P. deltoides and characterize it utilizing techniques like Fourier Transform Infrared Spectroscopy (FTIR), Micro Raman Spectroscopy, X-ray Powder Diffractometry (XRD), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM). The existence of C-O-C glycosidic connection (1156 cm-1), NHCO group (1216 cm-1), aliphatic compound, -CH2 bend (1418 cm-1), and asymmetric CH2 stretching were verified by FTIR analysis (1204 cm-1). Chitosan extract exhibited a greater degree of deacetylation of 55.17%, which is consistent with prior studies. The highest peaks in the Micro Raman Spectra were 2937 cm-1, 1106 cm-1, and 1376 cm-1. The crystallinity of the chitosan at 2θ was anticipated using X-ray Powder Diffractometry (XRD) data at about 20°-25°. SEM micrograms verified the crystalline nature of the chitosan by revealing its soft and crystal-like arrangement of the chitosan. TGA was used to assess the sample's thermal constancy, and the chitosan's stability was found to be consistent with that of prior research.

Living supramolecular polymerization of fluorinated cyclohexanes

The development of powerful methods for living covalent polymerization has been a key driver of progress in organic materials science. While there have been remarkable reports on living supramolecular polymerization recently, the scope of monomers is still narrow and a simple solution to the problem is elusive. Here we report a minimalistic molecular platform for living supramolecular polymerization that is based on the unique structure of all-cis 1,2,3,4,5,6-hexafluorocyclohexane, the most polar aliphatic compound reported to date. We use this large dipole moment (6.2 Debye) not only to thermodynamically drive the self-assembly of supramolecular polymers, but also to generate kinetically trapped monomeric states. Upon addition of well-defined seeds, we observed that the dormant monomers engage in a kinetically controlled supramolecular polymerization. The obtained nanofibers have an unusual double helical structure and their length can be controlled by the ratio between seeds and monomers. The successful preparation of supramolecular block copolymers demonstrates the versatility of the approach.

Tinospora Cordifolia-An immunomodulatory drug in Ayurveda for prevention and treatment of Covid-19

‘COVID-19’ is a highly infectious disease caused by the virus SARS-CoV-2 and it becomes a global pandemic in a very short period. Currently, there is a lack of precise management or vaccine available to counteract this disease which mainly attacks the immune system of a body. To manage COVID-19 existing disease-modifying and anti-virals agents and are being repurposed. Many research types are conducted in the development of particular immunomodulators, anti-virals agent or vaccines for SARS-CoV-2. In Ayurveda concept of epidemic condition (Janapadodhwanasa) is explained and various measures mentioned for prevention and treatment against such conditions including Rasayan dravyas (immunomodulator drugs). Tinospora cordifolia (Willd.) Miers is one of an immune-modulator drug in Ayurveda which known to possess properties like antioxidant, immunomodulatory, anti-inflammatory, anti- antiallergic, antiviral hyperglycaemic etc. This herb chiefly contains compounds like glycosides, alkaloids, steroids, diterpenoid lactones, sesquiterpenoid, aliphatic compound. Scientific researches on this drug may provide a new approach as well as insight for prevention, management and development of new therapeutic entity to treat COVID-19. The current review focus on researches conducted on properties of Tinospora cordifolia in the view of possible application in the prevention and treatment of COVID-19.

Impacts of Organic Structures and Inherent Minerals of Coal on Soot Formation during Pyrolysis

The pyrolysis of four pairs of raw and acid-washed coals under N2 atmosphere was carried out in a drop tube reactor at 1250 °C. The results show that both organic structures and metal elements have an important influence on the formation of soot. The total area of aromatic and aliphatic hydrogen absorption bands is positively correlated with soot yield. Aromatic compounds have a greater contribution to soot and tar formation. The absorption band area of oxygen structures in coal FTIR spectra is negatively correlated with the soot conversion rate of tar. During pyrolysis, metal substances in coal can catalyze the dehydrogenation and deoxygenation of tar, reduce the content and stability of the aliphatic compound, and catalyze aromatic ring rupturing. More importantly, gasified metals can inhibit the polymerization reaction of aromatic compounds.

Getting Dirty: What Charcoal Can tell us

Most of us are familiar with charcoal from sketching with it at school, or using charcoal bricks for a barbecue. You will have noticed that it got your hands dirty, that it is brittle, and that it is quite light—at least, lighter than an equivalent piece of uncharred wood. You may also have associated the black residues left after a bonfire with charcoal. If you have been to an area where the vegetation has been destroyed by wildfire, you may have also noticed black residues of charcoal on the ground that make a crunching sound beneath your feet. Our first two examples of charcoal are both products of human manufacture. The bonfire charcoal is a naturally formed material, but still the link with wildfire may not be made. When we see images of burning vegetation it is natural to imagine that all the plant material is consumed by the flames. Yet, as I came to realize on my visit to the site of the Hayman Fire, there is often a significant quantity of unburned material, and charcoal residues as well. Why are we left with charcoal after a fire? Charcoal is produced by heating plant material (most commonly wood, but not exclusively so) in the absence of oxygen. So it isn’t a product of the fire itself, but of the intense heat from the fire. Wood is essentially made up of two organic compounds: cellulose and lignin. Both compounds consist of carbon, hydrogen, and oxygen, but they differ in structure and therefore in properties. In cellulose, the carbon atoms are arranged in straight lines (it is an example of an aliphatic compound). It is the material from which paper is made. In lignin, on the other hand, the carbons are arranged in rings (it is an aromatic compound), and it is this structure that gives wood its toughness and strength. Industrial charcoal is used for a variety of metallurgical processes, and as adsorbents and food additives, as well as for barbecues and artists’ materials, so its formation has been carefully studied.

Heavy metal uptake by chemically distinct lichens from Aspicilia spp. growing on ultramafic rocks

Accumulation of metals in four crustose lichens with different secondary chemistry growing on serpentinite was studied. Aspicilia cinerea and A. blastidiata contain depsidone norstictic acid, A. goettweigensis contains stictic acid, and A. contorta ssp. hoffmanniana contains aliphatic compound aspicilin. The highest concentrations in lichens compared with serpentinite were found for calcium (Ca; average 11 times, maximum 20 times). Strontium (Sr), Copper (Cu), sodium (Na), zinc (Zn) and chromium (Cr) were 2.8–9 times greater in lichens than in rocks, and other elements such as nickel (Ni), iron (Fe), cobalt (Co), manganese (Mn) and magnesium (Mg) were equal or lower in the thalli than in the substrate. Three species showed little differences in concentrations of the same metals, whereas Aspicilia blastidiata, which is obligate to serpentinite, had statistically higher concentrations of most elements. This implies that the difference in secondary chemistry does not strongly influence accumulation rates of metals in selected species on serpentinite but that lichens have both mechanisms of accumulation and avoidance that may be related to ‘lichen acids’.

Aliphatic compounds, organic C and N and microbial biomass and its activity in long-term field experiment

The content of aliphatic compounds, hydrophobicity index, organic C and N content and the microbial biomass and respiration activity were analysed in soil samples originating from different plots of a long-term field experiment (variants: nil, NPK – mineral fertilization: 64.6–100 kg/ha/year, FYM – farmyard manure and FYM + NPK) from three blocks (III, IV and B) with different crop rotation. Samples were taken from 0–200 mm layer in 2002 and 2003 (spring and autumn). The plots without any fertilization had the significantly lowest aliphatic compound content compared to variants fertilized by FYM or FYM + NPK in all the evaluated blocks in both years. The variants fertilized only by mineral NPK without any organic fertilization had the slightly increased aliphatic compound content but they did not exceed significantly the control variants in most cases. The aliphatic compound contents correlated significantly with the organic C contents in 2002 and 2003, as well. The values of the hydrophobicity index showed a similar trend like the data mentioned above. Organic manure increased the soil organic nitrogen content, similarly to the carbon content. In variants fertilized by FYM and FYM + NPK the higher microbial biomass content was found comparing to unfertilized variants. Correlations between aliphatic compound content and biomass differed in spring (2002: r = 0.065, 2003: r = 0.068) and autumn (2002: r = 0.407, 2003: r = 0.529). Organically fertilized variants had increased basal respiration, in autumn 2002 the basal respiration was higher in variants fertilized by mineral NPK, too. The highest specific respiration was recorded in the unfertilised plot in block B (autumn 2002 and 2003), where low microbial biomass exhibited high activity. Increased specific respiration was found also in plots fertilized by FYM and FYM + NPK (block III and IV, autumn samplings). Positive significant correlations between microbial biomass content and basal respiration were found in 2002 (spring: r = 0.716) and 2003 (spring: r = 0.765, autumn: r = 0.671).