Green synthesis aspects of (R)-(-)-mandelic acid; a potent pharmaceutically active agent and its future prospects.

(R)-(-)-mandelic acid is an important carboxylic acid known for its numerous potential applications in the pharmaceutical industry as it is an ideal starting material for the synthesis of antibiotics, antiobesity drugs and antitumor agents. In past few decades, the synthesis of (R)-(-)-mandelic acid has been undertaken mainly through the chemical route. However, chemical synthesis of optically pure (R)-(-)-mandelic acid is difficult to achieve at an industrial scale. Therefore, its microbe mediated production has gained considerable attention as it exhibits many merits over the chemical approaches. The present review focuses on various biotechnological strategies for the production of (R)-(-)-mandelic acid through microbial biotransformation and enzymatic catalysis; in particular, an analysis and comparison of the synthetic methods and different enzymes. The wild type as well as recombinant microbial strains for the production of (R)-(-)-mandelic acid have been elucidated. In addition, different microbial strategies used for maximum bioconversion of mandelonitrile into (R)-(-)-mandelic acid are discussed in detail with regard to higher substrate tolerance and maximum bioconversion.HighlightsMandelonitrile, mandelamide and o-chloromandelonitrile can be used as substrates to produce (R)-(-)-mandelic acid by enzymes.Three enzymes (nitrilase, nitrile hydratase and amidase) are systematically introduced for production of (R)-(-)-mandelic acid.Microbial transformation is able to produce optically pure (R)-(-)-mandelic acid with 100% productive yield.

Antiviral potential of anthraquinones from Polygonaceae, Rubiaceae and Asphodelaceae: Potent candidates in the treatment of SARS-COVID-19, A comprehensive review.

Medicinal plants are being used as an alternative source of health management to cure various human ailments. The healing role is attributed to the hidden dynamic groups of various phytoconstituents, most of which have been recorded from plants and their derivatives. Nowadays, medicinal plants have gained more attention due to their pharmacological and industrial potential. Aromatic compounds are one of the dynamic groups of secondary metabolites (SM) naturally present in plants; and anthraquinones of this group are found to be attractive due to their high bioactivity and low toxicity. They have been reported to exhibit anticancer, antimicrobial, immune-suppressive, antioxidant, antipyretic, diuretic and anti-inflammatory activities. Anthraquinones have been also shown to exhibit potent antiviral effects against different species of viruses. Though, it has been reported that a medicinal plant with antiviral activity against one viral infection may be used to combat other types of viral infections. Therefore, in this review, we explored and highlighted the antiviral properties of anthraquinones of Polygonaceae, Rubiaceae and Asphodelaceae families. Anthraquinones from these plant families have been reported for their effects on human respiratory syncytial virus and influenza virus. They are hence presumed to have antiviral potential against SARS-CoV as well. Thus, anthraquinones are potential candidates that need to be screened thoroughly and developed as drugs to combat COVID-19. The information documented in this review could therefore serve as a starting point in developing novel drugs that may help to curb the SARS-COVID-19 pandemic.

Development of effective biotransformation process for benzohydroxamic acid production using Bacillus smithii IIIMB2907.

The present study entails the usefulness of thermophilic amidase-producing bacterium in the biotransformation of benzamide to benzohydroxamic acid (BHA). A bacterium Bacillus smithii IIIMB2907 was isolated from a soil sample collected from hot springs of Manikaran, Himachal Pradesh, India. The whole cells of the bacterium displayed versatile substrate specificity by exhibiting significant activity with a diverse range of amides. In addition, amidase from thermophilic bacterium was induced by adding Ɛ-caprolactam in the mineral base media. The optimum temperature and pH of acyltransferase activity of amidase enzyme were found to be 50 °C and 7.0, respectively. Interestingly, half-life (t 1/2) of this enzyme was 17.37 h at 50 °C. Bench-scale production and purification of BHA was carried out at optimized conditions which resulted in the recovery of 64% BHA with a purity of 96%. Owing to this, the reported process in the present study can be considered of immense industrial significance for the production of BHA. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-022-03109-2.

Exploitation of E. coli for the production of penicillin G amidase: a tool for the synthesis of semisynthetic ß-lactam antibiotics.

BACKGROUND: Penicillin G amidase/acylases from microbial sources is a unique enzyme that belongs to the N-terminal nucleophilic hydrolase structural superfamily. It catalyzes the selective hydrolysis of side chain amide/acyl bond of penicillins and cephalosporins whereas the labile amide/acyl bond in the ß-lactam ring remains intact. This review summarizes the production aspects of PGA from various microbial sources at optimized conditions. The minimal yield from wild strains has been extensively improved using varying strain improvement techniques like recombination and mutagenesis; further applied for the subsequent synthesis of 6-aminopenicillanic acid, which is an intermediate molecule for synthesis of a wide range of novel ß-lactam antibiotics. Immobilization of PGA has also been attempted to enhance the durability of enzyme for the industrial purposes. SHORT CONCLUSION: The present review provides an emphasis on exploitation of E. coli to enhance the microbial production of PGA. The latest achievements in the production of recombinant enzymes have also been discussed. Besides E. coli, other potent microbial strains with PGA activity must be explored to enhance the yields.

Production of salicylic acid; a potent pharmaceutically active agent and its future prospects.

Salicylic acid is one of the potent pharmaceutical organic acids that have various applications in the medical field. It acts as a plant hormone and helps in plant's growth & defence against pathogens. Beyond its numerous functions in plants, SA has great pharmaceutical importance since it acts as an intermediate for the synthesis of various drugs and dyes e.g. aspirin. At the industrial scale, chemical methods are used for the synthesis of SA but presently, several other sources are available that have the capability to alternate the chemical process which will be a step forward toward green synthesis. Aim of this paper is to provide comprehensive knowledge of SA production and its biological application.

A comprehensive review on Morchella importuna: cultivation aspects, phytochemistry, and other significant applications.

Morchella importuna is one of the most highly priced edible mushrooms and a rich source of bioactive substances with numerous beneficial medicinal properties. It has been artificially cultivated in the last few years but due to the unclear mechanism of its fruiting body formation, the stable production has not been achieved yet. This review aims to provide the detailed information about the current research status of the indoor and outdoor cultivation and significant applications of M. importuna worldwide with a vision to know more about its potential therapeutic index and edible values. It will provide the basis of better understanding about the need to develop biotechnological processes for morel farming under controlled conditions.

Bioprocess and genetic engineering aspects of ascomycin production: a review.

BACKGROUND: Ascomycin is a highly valuable multifunctional drug which exhibits numerous biological properties. Being an immunosuppressant, it is known to prevent graft rejection in humans and has potential to treat varying skin ailments. Its derivatives represent a novel class of anti-inflammatory macrolactams. But the biosynthetic machinery of ascomycin is still unclear. Due to the structural complexity, there occurs difficulty in its chemical synthesis; therefore, microbial production has been preferred by using Streptomyces hygroscopicus subsp. ascomyceticus. Through several genetic manipulation and mutagenesis techniques, the yield can be increased by several folds without any difficulties. Genetic engineering has played a significant role in understanding the biosynthetic pathway of ascomycin. SHORT CONCLUSION: Recently, many efforts have been made to utilize the therapeutic effects of ascomycin and its derivatives. This article covers concepts related to the production kinetics of ascomycin including an update of the ongoing yield improvement techniques as well as screening method of novel strains for ascomycin production.

Production aspects of testosterone by microbial biotransformation and future prospects.

In human males, TS plays a key role in maintaining health and sexual functioning. Cholesterol acts as a precursor molecule for its biosynthesis. The microbial biotransformation of cholesterol by numerous microbes like bacteria, fungi, yeasts, etc. has led to the synthesis of TS out of human body making it a great example for industrial steroid production due to its therapeutic properties. Biotransformation through microbes is more advantageous over chemical synthesis as it gives higher conversion rates, higher specificity; reaction goes under mild conditions like temperature and neutral pH, thus being an effective alternate to chemical route. Current review focuses on production aspects of TS by microbial biotransformation and its future prospects with recent advancement.

Exploring a broad spectrum nitrilase from moderately halophilic bacterium Halomonas sp. IIIMB2797 isolated from saline lake.

Nitrile hydrolyzing moderate halophilic bacterium Halomonas sp. IIIMB2797 was isolated from Sambhar Lake, India. Maximum cell biomass and nitrilase production were observed at 60 g L-1 NaCl in the production media which confirms its moderate halophilic nature. Nitrilase of Halomonas sp. IIIMB2797 proved to be inducible in nature as maximum activity was observed when valeronitrile was added in the production media. Whole cells of Halomonas sp. IIIMB2797 exhibited broad substrate affinity towards aromatic and aliphatic nitriles. Optimum pH and temperature for nitrilase activity was observed at 7.0 and 45 °C, respectively. Effect of salinity on nitrilase activity was also studied and maximum activity was observed in presence of 50 g L-1 NaCl in 0.1 M phosphate buffer of pH 7.0. The interesting feature of the study is that whole cells of Halomonas sp. IIIMB2797 exhibited higher nitrilase activities in presence of organic solvents which may be useful in biotransformation of nitriles to corresponding carboxylic acids for industrial applications.