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This study is aimed to cost-effectively produce bacterial cellulose (BC) and impart it with antimicrobial activity by introducing bactericidal plant extracts into its three-dimensional matrix through an ex situ modification strategy. Briefly, the fruit wastes were utilized as the carbon source for BC production by Gluconacetobacter hansenii, followed by impregnation of bioactive extracts of Anogeissus dhofarica and Withania somnifera plants. FE-SEM and FTIR analyses showed the successful synthesis of BC-Anogeissus dhofarica (BC-A) and BC-Withania somnifera (BC-W) composites. Both BC-A and BC-W composites held 87% and 75% water of their dry weight, respectively, and each composite retained about 50% of originally absorbed water after 24 h. The bactericidal activities of BC-A and BC-W composites were investigated against Staphylococcus aureus and Escherichia coli as model Gram-positive and Gram-negative pathogens, respectively. Both BC-A and BC-W composites showed impressive antibacterial activity against S. aureus by producing a clear inhibition zone of 13 mm and 6 mm, respectively. Although no clear inhibition zone was observed against E. coli, both composites reduced its growth up to 50% of its live cell density. This is the first report of exploring the antibacterial activities of A. dhofarica and W. somnifera plant extracts and developing their composites with BC, which could be of vital importance for natural products and biopolymer researchers to develop biomedical materials. ToC. Low-cost production and ex situ impregnation of bioactive plant-extract into bacterial cellulose matrix showing antibacterial activity.

Biomaterials are receiving tremendous attention, especially in the biomedical field, due to their impressive structural, physiological, and biological properties, such as nontoxicity, biocompatibility, and biodegradability. Numerous biomaterials have been used to fabricate scaffolds for applications in tissue engineering and regenerative medicine, where they are used as wound dressings, grafts, organs, and substitutes. To date, a number of techniques have been developed for the fabrication of scaffolds from biomaterials. This chapter focuses on the fabrication of scaffolds by solvent casting and melt-casting techniques. It examines the solvent casting and melt.casting techniques in terms of their application in the fabrication of biological scaffolds with tailored micro- and nanostructures for their use in tissue engineering. The merits and limitations of these techniques in fabricating biological scaffolds for desired biomedical applications are also discussed. Finally, various challenges faced by solvent and melt casting techniques are described, and solutions are proposed for future research to develop biomaterials for advanced biomedical applications.

Bacterial cellulose (BC) has received remarkable interest in numerous fields of life due to its multiple applicabilities. Despite chemical similarities with plant cellulose, BC offers exceptional structural and physicomechanical features that in turn lead to a broad range of applications in medical, pharmaceutical, food, cosmetic, textile, and many other industries. Currently, the major limitation associated with BC is its high cost, which confines the applications to certain limits. This chapter reviews the efforts made over the last three decades toward cost-effective BC production using waste by-products and low-cost carbon sources. Though industrial waste is also rich in cellulose contents, the findings revealed that food and municipal waste are the best candidates for BC production. Thus, BC provides an economical way to manage waste. Despite remarkable physicomechanical and morphological features, high production cost and time-consuming production mechanics are still a challenge to overcome that impact BC penetration and utilization. A few proposed solutions for overcoming those challenges are through developing genetically modified BC strains, designing novel bioreactors, and exploring alternative carbon sources. Herein, we have summarized the efforts made to explore novel, inexpensive, and natural raw sources for BC production. Indeed, the ideas presented here could capture the attention of industrialists and researchers working for developing BC production industries.

Gadolinium (Gd) based contrast agents (CAs) (Gd-CAs) represent one of the most advanced developments in the application of Gd for magnetic resonance imaging (MRI). Current challenges with existing CAs generated an urgent requirement to develop multimodal CAs with good biocompatibility, low toxicity, and prolonged circulation time. This review discussed the Gd-CAs used in bioimaging applications, addressing their advantages and limitations. Future research is required to establish the safety, efficacy and theragnostic capabilities of Gd-CAs. Nevertheless, these Gd-CAs offer extraordinary potential as imaging CAs and promise to benefit bioimaging applications significantly.

Bacterial cellulose (BC) has received immense interest in medical, pharmaceutical, and other related fields owing to its intrinsic physical, mechanical, and biological features. Its structural features offer an ideal environment for developing composites, thereby further extending its areas of applications. BC was initially used in wound dressing, artificial blood vessels, organ development, and tissue regeneration; however, the recent focus has switched to 3D printing techniques. BC can serve as suitable material for treating different cancers due to unique liquid absorbing and drug loading properties. BC-based scaffolds have been synthesized and tested for in vitro culturing of cancer cells to simulate tumor microenvironments. These scaffolds support normal growth of cancer cells, particularly breast and ovarian cancer cells, showing significant adhesion, proliferation, ingrowth, and differentiation. This review describes the different approaches of manipulating BC for use in medicine, with particular focus on the applications of BC composites in cancer treatment. A detailed discussion about various formulations of BC in multiple cancer therapeutics is summarized.

Equol (4',7-isoflavandiol), is a phytoestrogenic compound, which is synthesized from parent molecule diadzein by intestinal bacterial flora. It is among one of the most extensively researched molecule due to its high affinity towards estrogen receptors. Its enantiomeric form S-equol has been explored in the treatment of estrogen/androgen mediated diseases. Various therapeutic applications such as anti-cancer, cardioprotective, antidiabetic, antiosteoporosis, anti-ageing, and neuroprotective efficacy are attributed to it. This review explored major studies related to biochemistry and pharmacological applications of equol for human health.

Genistein is a natural compound belonging to the chemical class of isoflavone. This molecule is present in the significant portion of our diet in the form of Soy food products. This is the most extensively studied isoflavone due to its significance affinity towards targets of potential pharmacological and neutraceutical benefits. The potential pharmacological applications of this molecule have been found as anti-cancer, anti-obesity, anti-diabetic, neuroprotective, antiosteoporosis, and cardio protective agent. This review provides comprehensive coverage of the chemistry, pharmacology, toxicity and extraction of genistein.

A reverse phase high performance liquid chromatographic method is developed for the quantitation of glabridin in Glycyrrhiza glabra, using C18 column with acetonitrile-water containing 2% AcOH (70:30) as an eluent. Glabridin is detected by UV absorption at 280 nm after separation by the chromatographic system. Good linearity was obtained in the working range of the concentration (0.01–0.1 mg mL−1), with correlation coefficients 0.999. Limit of detection and limit of quantitation were 0.0195 and 0.065 mg mL−1. The method was validated under ICH guidelines. The described method can be utilized for routine analysis (assays and stability tests) of G. glabra extracts and Ayurvedic medicine based on Yashti-madhu.

Several diverse analogues of Oenostacin, a naturally occurring potent antibacterial phenolic acid derivative, have been synthesized. A small library with more than forty analogues having different aromatic rings and varied side chains has been achieved through solution phase synthesis. Some of these analogues, that is, 22 , 23 and 42 , possessed potent antibacterial activities against Staphylococcus epidermidis and Staphylococcus aureus having EC 50 ranging from 0.49 to 0.67 μM as compared to Oenostacin (EC 50 = 0.12 μM).

Ethanol extracts of nine lichen species, namely Everniastrum cirrhatum (Fr.) Hale ex Sipman (Parmeliaceae), Flavoparmelia caperata (L) Hale (Parmeliaceae), Heterodermia leucomela (L) Poelt (Physciaceae), Lecanora flavidorufa Hue (Lecanoraceae), Leptogium pedicellatum P.M. Jorg (Collemataceae), Lobaria isidiosa (Bory) Trevisan (Stictaceae), Rimelia reticulata (Taylor) Hale and Fletcher (Parmeliaceae), Phaeophyscia hispidula (Ach.) Essl (Physciaceae), and Stereocaulon foliolosum Nyl. (Stereocaulaceae), were evaluated for antimycobacteral properties against Mycobacterium tuberculosis H37Rv and H37Ra strains using the radiometric BACTEC method. Among the tested lichens, the virulent strain of M. tuberculosis H37Rv was found more susceptible to ethanol extract of F. caperata and H. leucomela (MIC 250mg=mL). E. cirrhatum, R. reticulata, and S. foliolosum were found active at the concentration of 500mg=mL. L. isidiosa, L. pedicellatum, P. hispidula ,a ndL. flavidorufa did not exhibit activity at the maximum tested concentration of 1000mg=mL.

Glabridin, an active constituent of Glycyrrhiza glabra roots, was found to be active against both yeast and filamentous fungi. Glabridin also showed resistance modifying activity against drug resistant mutants of Candida albicans at a minimum inhibitory concentration of 31.25-250 microg/mL. Although the compound was reported earlier to be active against Candida albicans, but this is the first report of its activity against drug resistant mutants.

Artemisinin, a sesquiterpene lactone, is the active antimalarial constituent of Artemisia annua. Several fungal strains Saccharomyces cerevisiae, Aspergillus flavus, Aspergillus niger and Picchia pastoris were used to biotransform artemisinin. Among these strains, A. flavus was the only microorganism capable of transforming artemisinin to deoxyartemisinin in higher yields than the previous reports. The structure of deoxyartemisinin was elucidated by spectroscopy. Deoxyartemisinin showed antibacterial activity against Staphylococcus aureus, S. epidermidis and S. mutans at a minimum inhibitory concentration (MIC) of 1 mg/mL compared to artemisinin whose MIC was &gt, 2 mg/mL.

The present study was aimed to investigate antimicrobial potential of Glycyrrhiza glabra roots. Antimycobacterial activity of Glycyrrhiza glabra was found at 500 microg/mL concentration. Bioactivity guided phytochemical analysis identified glabridin as potentially active against both Mycobacterium tuberculosis H(37)Ra and H(37)Rv strains at 29.16 microg/mL concentration. It exhibited antimicrobial activity against both Gram-positive and Gram-negative bacteria. Our results indicate potential use of licorice as antitubercular agent through systemic experiments and sophisticated anti-TB assay.