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Plant–microbe interactions are crucial for many ecological processes. These interactions majorly take place in the rhizosphere and are mediated by the secretion of organic compounds by plant roots. These compounds act as signalling molecules and also as carbon sources for microbes. Microbial community in the rhizosphere is very diverse and consists of bacteria, archaebacteria, viruses, fungi, actinomycetes, protozoans, arthropods, algae, and nematodes. The rhizospheric microbes promote plant growth by different mechanisms such as biocontrol activity, phytohormone secretion, siderophore production, mineral solubilization, nitrogen fixation, and enzyme production. Since, a large proportion of microbial diversity is still not cultured, the detection and phylogenetic characterization of such un-/non-cultured microorganisms require advanced molecular techniques viz. metagenomics, metabolomics, metatranscriptomics, and metaproteomics. Several factors affect the rhizosphere microbial population, including root exudates, type and age of the plant, status of plant health, and application of fertilizers, pesticides, and amendments. Plant growth-promoting microbes of the rhizosphere can be used as biofertilizers and biocontrol agents and rhizosphere competence is an important factor that determines their success. This chapter discusses all these aspects of rhizospheric microbial communities, especially their occurrence, distribution, and functions.

Nonobstetric surgery during pregnancy is common. Administration of safe anesthesia to a pregnant patient, while minimizing its side effects on the fetus, is a major challenge for the anesthesiologist. Both general anesthesia and central neuraxial block are associated with risks during early pregnancy. Regional nerve blocks are being explored as possible alternatives whenever feasible. This report emphasizes the usefulness of ultrasound-guided, modified bilateral paravertebral block in a first-trimester pregnant patient undergoing microdiscectomy for cauda equina syndrome.

Cellulose is one of the most significant renewable energy sources present on earth and is also the most abundant biomolecule present in biomass. Hence producing indigenous cellulases for depolymerization of cellulose for use in various bioprocesses, namely biofuel production and commodity biochemical synthesis, is vital for the development of sustainable future biorefineries. Cellulolytic enzymes are a set of several enzymes, produced mainly by microorganisms both fungi and bacteria, that synergistically catalyze degradation of holocellulose-releasing oligosaccharides, cellobiose, and glucose units. Interestingly, cellulases are inducible enzymes, whose regulation is precisely regulated by activation and repression mechanisms. These inducible enzymes are produced only in the presence of complex cellulosic substrates, but repressed when simple sugars are present. The cellulosic substrates can either be pure substrates (cellulose powder) or raw lignocellulosic material. Lignocellulosic biomass, being plentiful as well as inexpensive, is usually the preferred substrate for the production of this enzyme system as compared to the pure substrates. Recent transcriptome profiling and quantitative proteomic approaches also reveal induction of specific proteins in the presence of utilizable lignocellulosic carbon sources by different microorganisms. This chapter discusses various pure and lignocellulosic substrates used for microbial cellulase production by either liquid submerged or solid-state fermentation.

A novel thermotolerant Streptomyces sp. ssr-198 with capacity to produce multicomponent holocellulolytic enzymes was isolated and identified using 16S rDNA sequencing. Important chemical components of medium were optimized by rotatable central composite design (RCCD) using response surface methodology (RSM) to achieve maximal yield of holocellulolytic (endoglucanase, exoglucanase and xylanase) enzymes. Optimization resulted in 246%, 83%, and 96% higher yield of endoglucanase, exoglucanase and xylanase respectively as compared to unoptimized conditions. The concentrated crude enzymes were partially characterized in terms of optimum pH (6.0) and temperature (60 °C). Multiple endoglucanase and xylanases with diverse molecular weights were detected in the zymogram. The study demonstrated the ability of this newly isolated Streptomyces strain to produce a high titer of holocellulolytic enzymes with potential application in the saccharification of lignocellulosic biomass.

Geriforte, an herbomineral compound prepared from several herbs and minerals, is being used as a restorative tonic to solve the problems of old age in India. Since active oxygen species have been proposed to be involved in the aging process of the brain, alterations in the level of enzymes involved in the defense system against free radicals and other active oxygen species could substantially influence the aging process. Therefore, in the present study, this antistress adaptogenic Ayurvedic preparation has been evaluated for the activities of superoxide dismutase (SOD) and catalase (CAT), key enzymes of the cellular defense system, in the brain of aging Wistar male rats. The present study was carried out on 22-month-old rats. They were given Geriforte powder orally at a dosage of 900 mg/kg body weight once a day for two months. The Geriforte-treated rat brain had significantly high levels of SOD and CAT activities than those recorded in their respective controls. The contents of SOD and CAT in Geriforte-administered brain increased by 24% and 30%, respectively. In the present investigation, free radical damage was assessed by measuring thiobarbituric acid reactive substance (TBARS) in postmitochondrial fractions of brain homogenate. The magnitude of TBARS has been reported to be decreased by 26% in the Geriforte-treated rat brain. In conclusion, it seems logical to suppose that Geriforte, a combination of several plant ingredients and minerals, protects the body against the damaging effects of free radicals by producing large amounts of antioxidant enzymes.