The deleterious effects of synthetic dyes evoked great enthusiasm in many scientists to search for eco-friendly natural colorants for morphological study and identification of microorganisms. The aim of the study was to develop a mycological staining reagent from the red pigments extracted from beet root pomace (Beta vulgaris L.). Beet root rich in water soluble betalains was extracted with distilled water at 40ºC.The conventional easy and economical wet mount procedure was followed to prepare the fungal slides. Glycerol was used as a hygroscopic agent which did not affected the colour of the extract. In the current investigation the extract was evaluated as a staining reagent to study the morphology of the test fungal samples viz. Rhizopus sp., Microsporum gypseum and Aspergillus niger. The study revealed that the use of citric acid buffer intensified its red colour potentially at pH 5.This novel staining reagent was proved to be reliable and safe with satisfactory visual clarity of the characteristic fungal structures. In conclusion, this ecofriendly alternative method of staining by such non-toxic vegetal active principle provided a promising way to support environmental sustainability.

Objective: The present study aimed to evaluate dried pomegranate peels as a substrate for citric acid production by Aspergillus niger. Methods: The morphological study of Aspergillus niger was carried out by wet mount with lactophenol cotton blue and slide culture method. A preliminary qualitative screening of citric acid-producing ability of this fungal strain was also performed by using the Czapek-Dox agar medium containing Bromocresol green. Dried and finely powdered Pomegranate peel was used as a principal substrate for the production of citric acid by submerged fermentation. Classical method of citric acid recovery involved a precipitation technique using calcium hydroxide followed by filtration and subsequent treatment with sulphuric acid. The citric acid produced was also chemically detected and titrimetrically estimated by 0.1 N NaOH. Results: The present experiment demonstrated that pomegranate peels may serve as an inexpensive medium for the production of citric acid with a yield of 19.39 g/l by using Aspergillus niger. Conclusion: This study provided an alternative basis to recycle the fruit peel waste of pomegranate in order to achieve industrially feasible and environmentally sustainable bio-production of pharmaceutically significant citric acid.

No abstract

No abstract