The role of organic nutrients in structuring freshwater phytoplankton communities in a rapidly changing world.

Carbon, nitrogen, and phosphorus are critical macroelements in freshwater systems. Historically, researchers and managers have focused on inorganic forms, based on the premise that the organic pool was not available for direct uptake by phytoplankton. We now know that phytoplankton can tap the organic nutrient pool through a number of mechanisms including direct uptake, enzymatic hydrolysis, mixotrophy, and through symbiotic relationships with microbial communities. In this review, we explore these mechanisms considering current and projected future anthropogenically-driven changes to freshwater systems. In particular, we focus on how naturally- and anthropogenically- derived organic nutrients can influence phytoplankton community structure. We also synthesize knowledge gaps regarding phytoplankton physiology and the potential challenges of nutrient management in an organically dynamic and anthropogenically modified world. Our review provides a basis for exploring these topics and suggests several avenues for future work on the relation between organic nutrients and eutrophication and their ecological implications in freshwater systems.

Indian spices: past, present and future challenges as the engine for bio-enhancement of drugs: impact of COVID-19.

Spices are natural plant products enriched with the history of being used as herbal medicine for prevention of diseases. India is also known as the 'Land of Spices'. Out of 109 spices recognized by the International Organization for Standardization (ISO) more than 52-60 spice crops are grown in India. The major spices exported by India are turmeric, cumin, coriander, fenugreek, peppers, etc. The Indian spices are divided into three era viz. early period, middle age and early modern period. Spices are used in beverages, liquors, and pharmaceutical, cosmetic and perfumery products. The major issue with spices is their handling and storage. This review article mainly focuses on two aspects: at the outset the handling and storage of the spices is an essential factor as spices are available in different forms like raw, processed, fresh, whole dried, or pre-ground dried. Therefore, the need of processing, packaging, storage and handling of the spices is important as the deterioration of spices can lead to the loss of therapeutic activity. Furthermore, many herbal constituents have the capability to enhance the bioavailability of drugs. Therefore, an attempt has been made to throw a light on the bioenhancer activity and therapeutic activity along with their mechanism of action of some Indian spices which are regularly used for cooking purpose on a daily basis to enhance the taste of food. The spices suggested by ministry of AYUSH which is relevant to its medicinal and biological property in treatment and prevention from COVID-19 are discussed. © 2022 Society of Chemical Industry.