The effect of the tidal cycle on the phytoplankton community assemblage in a mangrove-dominated tropical tidal creek.

A comparative assessment of phytoplankton dynamics during low tide (LT) and high tide (HT) was conducted from February 2022 to January 2023 in a tropical mesotidal creek, Manori, Mumbai, India. In total, 124 phytoplankton species were recorded. The HT resulted in greater species richness (124 species) and diversity indices (Shannon-Wiener's index) than the LT (102 species). The Pielou's evenness (J') and Simpson's dominance index (1-D) did not show significant fluctuations with the tides due to the marine phytoplankton species moving rhythmically in and out of the creek with the tides. Overall, the seasonal abundance was maximum during pre-monsoon at HT (5.79 × 103 u/L) and lowest in monsoon at LT (0.45 × 103 u/L), whereas spatial abundance was maximum at S1 (HT- 4.04 × 103 u/L) at HT and lowest at S3 (LT- 0.75 × 103 u/L) at LT. The diatoms dominated in their abundance (1.83 × 103 u/L and 3.82 × 103 u/L in HT) and diversity (77 in LT and 92 in HT). The species such as Coscinodiscus centralis, Coscinodiscus granii, Coscinodiscus radiatus, Triops furca, Melosira varians, Nitzchsia palea, Chaetoceros affinis, Skeletonema marinoi, Stephanocyclus meneghinianus, Planktoniella sol and Skeletonema costatum were the dominant native residents in the creek. SIMPER analysis revealed that the maximum similarity was during the monsoon (47.65%), and the minimum was during the pre-monsoon (38.10%) at LT. However, in HT, the maximum similarity of phytoplankton shifted to post-monsoon (63.85%) and the minimum during the pre-monsoon (46.71%). The mean value of richness (d') and Shannon's diversity (H') showed a moderate phytoplankton diversity in the system. The environmental parameters (water temperature > pH > nitrate > salinity > DO > Alk > silicate) have a greater influence on the distribution of the phytoplankton community with tides as revealed by the Canonical correspondence analysis. Therefore, it has been found that tides play a significant role in the distribution and abundance of the phytoplankton community in a mesotidal creek environment.

Terpenoid and flavonoid spectrum of in vitro cultures of Glycyrrhiza glabra revealed high chemical heterogeneity: platform to understand biosynthesis.

Simultaneous qualitative and quantitative assessment of eight flavonoids and two terpenoids were performed in fourteen in vitro raised morphogenic cultures of Glycyrrhiza glabra. Our study revealed that the spectrum and production of ten compounds, under investigation, were higher in organized tissue than the undifferentiated mass, however, aerial portions of the in vitro raised plants (leaf and stem) were found to be devoid of therapeutically relevant triterpenoid, glycyrrhizin. A correlation was observed between cell maturation, morphological differentiation and glycyrrhizin accumulation. Mature stolons (4 months) were characterized by the maximum accumulation of glycyrrhizin (8.60 µg/mg) in in vitro plantlets. The cytotoxic effect of the extracts evaluated against a panel of human cancer cell lines (in vitro) indicated that the pancreatic cell line (MIA-PaCa-2) were sensitive to all the fourteen extracts investigated. To the best of our knowledge this is the first comprehensive report relating plant growth regulators to metabolite spectrum and cytotoxic assessment in in vitro raised G. glabra cultures. Overall, our findings demonstrated that the metabolite spectrum of in vitro raised morphogenetic lines, under different stages of maturation, might offer a platform to understand the regulatory aspects of the concerned metabolite pathway and their consequent role in differentiation.

Leptospira infection in animals and humans: a potential public health risk in India.

Leptospirosis is recognised as one of the commonest zoonotic infections in the world. In India, where animals provide the draught power for agriculture, which is the main profession of the population, the incidence of leptospirosis among animals and humans is high. In this paper, the isolation of pathogenic leptospires from human and animal hosts from several parts of India is reported. Because there are only limited facilities for serotyping within the country, most of the isolates were typed to the serogroup level only. In addition, the potential of leptospirosis to be a serious public health problem in India is discussed.