Valorization of Kappaphycus alvarezii through extraction of high-value compounds employing green approaches and assessment of the therapeutic potential of κ-carrageenan.

This study utilizes different emerging green extraction technologies to recover maximum value-added products from Kappaphycus alvarezii and evaluate their bio-functional properties. Using the supercritical fluid extraction (SFE) method, the total lipid yield of 0.21 ± 0.2 % was obtained from the biomass. Linoleic acid, eicosapentaenoic acid, arachidonic acid, γ-linolenic acid, and docosahexaenoic acid were present in higher concentrations (9.12 %) in the lipid extracted with SFE as compared to hexane (5.5 %). Using an ultrasonication assisted approach, ~56 % of κ-carrageenan was recovered from SFE residual biomass, which contains 28.5 ± 1.9 % sulfate content. It exhibited a monosaccharide content of 3,6-anhydrogalactose (~24 %) and galactose (~53 %), as well as rheological properties within FAO limitations that can be explored for food-grade applications. ~58 % of the total protein (12.5 %) from SFE residual biomass was recovered using subcritical water hydrolysis method. The effectiveness of κ-carrageenan in suppressing the 3CLpro of SARS-CoV-2 using in vitro and in silico approaches was investigated. κ-Carrageenan effectively inhibited the main protease by up to 93 % at 1.6 mg mL-1. In silico results revealed that κ-carrageenan successfully binds to the active site of the main protease while retaining the structural integrity and stability of protein-ligand complexes.

Deciphering the role of fucoidan from brown macroalgae in inhibiting SARS-CoV-2 by targeting its main protease and receptor binding domain: Invitro and insilico approach.

The current study investigated the role of fucoidan from Padina tetrastromatica and Turbinaria conoides against 3-chymotrypsin like protease (3CLpro) and receptor binding domain (RBD) spike protein of SARS-CoV-2 using an invitro and computational approach. The 3CLpro and RBD genes were successfully cloned in pET28a vector, expressed in BL-21DE3 E. coli rosetta cells and purified by ion exchange affinity and size exclusion chromatography. Fucoidan extracted from both biomass using green approach, subcritical water, was found to inhibit 3CLpro of SARS-CoV-2 with an IC50 value of up to 0.35 mg mL-1. However, fucoidan was found to be inactive against the RBD protein. Molecular docking studies demonstrated that fucoidan binds to the active sites of 3CLpro with an affinity of -5.0 kcal mol-1. In addition, molecular dynamic simulations recorded stabilized interactions of protein-ligand complexes in terms of root mean square deviation, root mean square fluctuation, the radius of gyration, solvent accessible surface area and hydrogen bond interaction. The binding energy of fucoidan with 3CLpro was determined to be -101.821 ± 12.966 kJ mol-1 using Molecular Mechanic/Poisson-Bolt-Boltzmann Surface Area analysis. Fucoidan satisfies the Absorption, Distribution, Metabolism, and Excretion (ADME) properties, including Lipinski's rule of five, which play an essential role in drug design. According to the toxicity parameters, fucoidan does not exhibit skin sensitivity, hepatotoxicity, or AMES toxicity. Therefore, this work reveals that fucoidan from brown macroalgae could act as possible inhibitors in regulating the function of the 3CLpro protein, hence inhibiting viral replication and being effective against COVID-19.

Immobilization-Based Bio-formulation of Aspergillus awamori S29 and Evaluation of Its Shelf Life and Re-usability in the Soil-Plant Experiment.

The present study was an attempt to evaluate the bio-formulations of phosphate-solubilizing fungus Aspergillus awamori S29 using two economically viable carriers (calcium alginate and agar) in repeated batch fermentation. Further, the viable cell count under storage and response of these stored bio-formulations on the growth of wheat plants were studied at the end of 2, 4, and 6 months of incubation. Also, the response of these formulations in next season on pearl millet (bajra) was studied without further inoculation. In repeated batch fermentation assay, immobilized form performed significantly better than free form. The viability of fungal inoculant was 88.2% in calcium alginate-based bio-formulation after six months of storage. These bio-formulations showed not only a statistically significant increase in the growth of wheat crop in first season but also of pearl millet in next season. This work strengthens the re-usability potential of immobilized bio-formulations for next season crop.

Cannabis: Chemistry, extraction and therapeutic applications.

Cannabis, a genus of perennial indigenous plants is well known for its recreational and medicinal activities. Cannabis and its derivatives have potential therapeutic activities to treat epilepsy, anxiety, depression, tumors, cancer, Alzheimer's disease, Parkinson's disease, to name a few. This article reviews some recent literature on the bioactive constituents of Cannabis, commonly known as phytocannabinoids, their interactions with the different cannabinoids and non-cannabinoid receptors as well as the significances of these interactions in treating various diseases and syndromes. The biochemistry of some notable cannabinoids such as tetrahydrocannabinol, cannabidiol, cannabinol, cannabigerol, cannabichromene and their carboxylic acid derivatives is explained in the context of therapeutic activities. The medicinal features of Cannabis-derived terpenes are elucidated for treating several neuro and non-neuro disorders. Different extraction techniques to recover cannabinoids are systematically discussed. Besides the medicinal activities, the traditional and recreational utilities of Cannabis and its derivatives are presented. A brief note on the legalization of Cannabis-derived products is provided. This review provides comprehensive knowledge about the medicinal properties, recreational usage, extraction techniques, legalization and some prospects of cannabinoids and terpenes extracted from Cannabis.

Enrichment of flaxseed (Linum usitatissimum) oil with carotenoids of sea buckthorn pomace via ultrasound-assisted extraction technique: Enrichment of flaxseed oil with sea buckthorn.

Currently, flaxseed oil is used as an important functional food constituent owing to its large content of omega-3 fatty acids. However, flaxseed oil does not contain carotenoids that could enhance the oxidative stability of the oil. In this study, carotenoids extracted from sea buckthorn pomace were used to enrich cold-pressed flaxseed oil via an ultrasound-assisted extraction technique (UAE). The process parameters were optimized through Box-Behnken design to maximize the carotenoid content in the flaxseed oil. The results obtained by statistical analysis indicated that the yield of 14.02 mg/L of carotenoid content was found in the enriched flaxseed oil at 75.6 min, feed to oil ratio of 19.9 (wt. basis), and amplitude 80.81%. Further, UAE at optimum process parameters was compared with the conventional extraction (CE) method, and it was found that UAE had ~ 49 wt% of higher carotenoid content relative to CE. The physicochemical properties of the enriched flaxseed oil were determined to evaluate the effects of carotenoid enrichment in the flaxseed oil. Based on the outcomes of the present investigation, enriched flaxseed oil could be the potential source for the pharmaceuticals and nutraceuticals industry.

Hydrothermal pretreatment technologies for lignocellulosic biomass: A review of steam explosion and subcritical water hydrolysis.

The pretreatment of lignocellulosic biomass enhances the conversion efficiency to produce biofuels and value-added chemicals, which have the potential to replace fossil fuels. Compared to physicochemical and other pretreatment techniques, the hydrothermal methods are considered eco-friendly and cost-effective. This paper reviews the strengths, weaknesses, opportunities and threats of steam explosion and subcritical water hydrolysis as the two promising hydrothermal technologies for the pretreatment of lignocellulosic biomass. Although the principle of the steam explosion in depolymerizing the lignin and exposing the cellulose fibers for bioconversion to liquid fuels is well known, its underlying mechanism for solid biofuel production is less identified. Therefore, this review provides an insight into different operating conditions of steam explosion and subcritical water hydrolysis for a wide variety of feedstocks. The mechanisms of subcritical water hydrolysis including dehydration, decarboxylation and carbonization of waste biomass are comprehensively described. Finally, the role of microwave heating in the hydrothermal pretreatment of biomass is elucidated.

Antiviral activity of sulfated polysaccharides from marine algae and its application in combating COVID-19: Mini review.

Marine-derived sulfated polysaccharides possess various antiviral activities against a broad range of enveloped and non-enveloped viruses. It has become the potential source of antiviral drugs for pharmaceutical development. In this review, we will discuss the different types of sulfated polysaccharides and their structural classification. Some of the major sulfated polysaccharides with potent antiviral activity, including carrageenan, agar, ulvan, fucoidan, and alginates, are considered in this review. The mechanism of these sulfated polysaccharides in inhibiting the different stages of the viral infection process inside the host cell is also demonstrated. It involves blocking the initial entry of the virus or inhibiting its transcription and translation by modulating the immune response of the host cell. In addition, we explore the potential of sulfated polysaccharides as antiviral agents in preventing recent Corona Virus Disease-2019 (COVID-19).

In Vitro Anticancer Activity of Virgin Coconut Oil and its Fractions in Liver and Oral Cancer Cells.

BACKGROUND: Coconut oil is an edible oil obtained from fresh, mature coconut kernels. Few studies have reported the anticancer role of coconut oil. The fatty acid component of coconut oil directly targets the liver by portal circulation and as chylomicron via lymph. However, the anti-cancer activity of coconut oil against liver cancer cells and oral cancer cells is yet to be tested. The active component of coconut oil, that is responsible for the anticancer activity is not well understood. In this study, three different coconut oils, Virgin Coconut Oil (VCO), Processed Coconut Oil (PCO) and Fractionated Coconut Oil (FCO), were used. OBJECTIVE: Based on previous studies, it can be hypothesized that fatty acids in coconut oil may have anticancer potential and may trigger cell death in cancer cell lines. METHODS: Each cell line was treated with different concentrations of Virgin Coconut Oil (VCO), Processed Coconut Oil (PCO) and Fractionated Coconut Oil (FCO). The treated cells were assayed by MTT after 72 hr of incubation. The fatty acid composition of different coconut oils was analyzed by gas chromatography. RESULT: Different concentrations of coconut oils were used to treat the cells. Interestingly, the anticancer efficacy of VCO, PCO and FCO was not uniform, rather the efficacy varied from cell line to cell line. Only 20% VCO showed significant anticancer activity in HepG2 cells in comparison to 80% PCO against the KB cell line. Remarkably, 20% of PCO and 5% of FCO showed potential growth inhibition in the KB cell line as compared to 80% PCO in HepG2 cells. Moreover, there was a difference in the efficacy of VCO, PCO and FCO, which might be due to their fatty acid composition. Comparing the anticancer efficacy of VCO, PCO and FCO in this study helped to predict which class of fatty acids and which fatty acid might be associated with the anticancer activity of VCO. CONCLUSION: This study shows that VCO, PCO and FCO have anticancer efficacy and may be used for the treatment of cancer, especially liver and oral cancer.

Supercritical CO2 fractionation of bio-oil produced from wheat-hemlock biomass.

The biomass i.e. wheat-hemlock used in this study was first characterized for its composition. The physical and chemical characterization of biomass was estimated using proximate analysis, calorific value, crystallinity, devolatilization behaviour, ultimate analysis, ICP-MS of ash, FT-IR, XRD, CHNS, and HPLC analysis. For commercial purpose the same biomass was used for conversion to bio-oil by fast pyrolysis process. Therefore, in order to investigate its composition, the bio-oil was also characterized using proximate analysis, calorific value, whereas the chemical composition of the bio-oil was estimated using CHNS, (1)H NMR, GC-FID and GC/MS. The bio-oil obtained from wheat-hemlock biomass was supplied by Advanced Biorefinery Co. and after the analysis, its composition has been determined. It contains a mixture of hydrocarbons, pyranoids, furanoids, benzenoids and fatty acids/alcohols with 45% of water, which forms azeotrope with organic polar compounds. The supercritical CO(2) (SC-CO(2)) is an advanced method for selective extraction of valuable chemicals from bio-oil without solvent residue. The organic fraction of the bio-oil was isolated by SC-CO(2). It was observed that SC-CO(2) fractions collected at 10 and 25 MPa pressure were enriched with furanoids, pyranoids and bezenoids. Similarly the bio-oil was also fractionated by conventional column chromatographic method and the yields and chemical compositions were compared with fractionated bio-oil obtained using SC-CO(2).