Narender Singh Atri

Optimization, Composition, and Antioxidant Activities of Exo- and Intracellular Polysaccharides in Submerged Culture of Cordyceps gracilis (Grev.) Durieu & Mont.

Under present experiments, EPS and IPS production, monosaccharide composition, and antioxidant activities of C. gracilis were studied for the first time under submerged culture conditions. Effect of different factors on polysaccharides production was studied by orthogonal experiments using one-factor-at-a-time method. Incubation of culture in the medium with capacity 200 mL (675.12 ± 5.01 and 385.20 ± 5.01 mg/L), rotation speed 150 rpm (324.62 ± 3.32 and 254.62 ± 4.62 mg/L), 6-day culture incubation time (445.24 ± 1.11, 216.60 ± 1.71 mg/L), pH 6.0 (374.81 ± 2.52 and 219.45 ± 2.59 mg/L), and temperature 23°C (405.24 ± 1.11 and 215.60 ± 1.71 mg/L) produced higher EPS and IPS, respectively. Maximum EPS and IPS production was observed in the medium supplemented with glucose as a carbon source (464.82 ± 2.12 and 264.42 ± 2.62 mg/L) and yeast extract as a nitrogen source (465.21 ± 3.11 and 245.17 ± 3.24 mg/L), respectively. Carbon to nitrogen ratio for maximum EPS and IPS production was observed as 10 : 1 (395.29 ± 2.15 and 235.62 ± 1.40 mg/L), respectively. Glucose was found to be the major monosaccharide (62.15 ± 7.33%). Both EPS and IPS of C. gracilis showed significant DPPH radical scavenging activity, ABTS radical scavenging activity, reducing power, and iron chelating activity.

Characterization of Lamellate Mushrooms—An Appraisal

Ever since the work on mushroom systematics started, it remained centred around conventional morphology-based parameters. Over a period of time with the advancement of microscopic techniques, the use of internal anatomical details and other microscopic features including SEM details strengthened the taxonomic conclusions leading to the discovery of newer characters for supplementing the morphological features. Simultaneously, the importance of macrochemical and microchemical reactions in mushroom systematics has been emphasized along with the utility of chemotaxonomic and numerical taxonomic methods, although all such characters play a supplementary role in their taxonomic categorization. All such studies enabled the mushroom mycologists to reach right taxonomic conclusions. Towards the end of 1990s, there has been a rapid transformation from conventional morphology-based system to contemporary molecular phylogenetic system based on sequence analysis employing next-generation sequencing technology. Presently, the scientists are trying to understand the higher level of relationship among lamellate mushrooms and their non-lamellate relatives by sequencing gene coding for several specific non-coding ribosomal DNA regions such as ITS, nLSU, nSSU, mitochondrial non-coding gene like mtSSU and protein coding genes such as rpb1, rpb2, atp6, tef1. Of late the use of newer techniques to study mushroom taxonomy and to understand their phylogeny has started slowly picking up in India as well, which is a welcome step. Mushrooms exhibit immense variation of shape, texture, colour, smell, taste and have varied ecological preferences. In the present paper, the importance of morphological, anatomical, chemical, numerical and molecular aspects in the characterization of mushrooms on modern lines has been discussed.

Taxonomical Establishment and Compositional Studies of a New Cordyceps (Ascomycetes) Species from the Northwest Himalayas (India)

During a frequent survey in the northwest Indian Himalayan region, a new species-Cordyceps macleodganensis-was encountered. This species is described on the basis of its macromorphological features, microscopic details, and internal transcribed spacer sequencing. This species showed only 90% resemblance to Cordyceps gracilis. The chemical composition of the mycelium showed protein (14.95 ± 0.2%) and carbohydrates (59.21 ± 3.8%) as the major nutrients. This species showed appreciable amounts of P-carotene, lycopene, phenolic compounds, polysaccharides, and flavonoids. Mycelial culture of this species showed higher effectiveness for ferric-reducing antioxidant power, DPPH radical scavenging activity, ferrous ion-chelating activity, and scavenging ability on superoxide anion-derived radicals, calculated by half-maximal effective concentrations.