25Phylogenetic diversity of cultivable actinobacteria isolated from sponges and associated 26 environments of intertidal zones, along the northern parts of west coast of India, were studied 27 using 16S rRNA gene sequences. A subset of actinobacteria were screened for three activities, 28 namely predatory behavior, antibacterial activity and enzyme inhibition. We recovered 207 29 isolates of actinobacteria belonging to 16 families and 25 genera, which could be attributed to 30 55 putative species using Poisson Tree Processes and 60 putative species based on Bayesian 31Poisson Tree Processes. Although the trends in the discovery of actinobacterial genera isolated 32 from sponges was consistent with previous studies from different study areas, we provide first 33 report of six actinobacterial species from sponges. We observed widespread non-obligate 34 epibiotic predatory behavior in eight actinobacterial genera and we provide first report of 35 predatory activity in Brevibacterium, Glutamicibacter, Micromonospora, Nocardiopsis, 36Rhodococcus and Rothia. Sponge associated actinobacteria showed significantly more 37 predatory behavior than environmental isolates. While antibacterial activity by actinobacterial 38 isolates mainly affected Gram-positive target bacteria with little to no effect on Gram-negative 39 bacteria, predation targeted both Gram-positive and Gram-negative prey with equal propensity. 40 Actinobacterial isolates from both sponge and associated environment produced inhibitors of 41 serine proteases and angiotensin converting enzyme. Predatory behavior was strongly 42 associated with inhibition of trypsin and chymotrypsin. Our study suggests that sponge and 43 associated environment of western coast of India are rich in actinobacterial diversity with 44 widespread predatory activity, antibacterial activity and production of enzyme inhibitors. 45

The phylogenetic diversity of cultivable actinobacteria isolated from sponges (Haliclona spp.) and associated intertidal zone environments along the northern parts of the western coast of India were studied using 16S rRNA gene sequences. A subset of randomly selected actinobacterial cultures were screened for three activities, namely predatory behaviour, antibacterial activity and enzyme inhibition. We recovered 237 isolates from the phylum Actinobacteria belonging to 19 families and 28 genera, which could be attributed to 95 putative species using maximum-likelihood partition and 100 putative species using Bayesian partition in Poisson tree processes. Although the trends in the discovery of actinobacterial genera isolated from sponges were consistent with previous studies from different study areas, we provide the first report of nine actinobacterial species from sponges. We observed widespread non-obligate epibiotic predatory behaviour in eight actinobacterial genera and we provide the first report of predatory activity in Brevibacterium , Glutamicibacter , Micromonospora , Nocardiopsis , Rhodococcus and Rothia . Sponge-associated actinobacteria showed significantly more predatory behaviour than environmental isolates. While antibacterial activity by actinobacterial isolates mainly affected Gram-positive target bacteria with little or no effect on Gram-negative bacteria, predation targeted both Gram-positive and Gram-negative prey with equal propensity. Actinobacterial isolates from both sponges and associated environments produced inhibitors of serine proteases and angiotensin-converting enzyme. Predatory behaviour was strongly associated with inhibition of trypsin and chymotrypsin. Our study suggests that the sponges and associated environments of the western coast of India are rich in actinobacterial diversity, with widespread predatory activity, antibacterial activity and production of enzyme inhibitors. Understanding the diversity and associations among various actinobacterial activities – with each other and the source of isolation – can provide new insights into marine microbial ecology and provide opportunities to isolate novel therapeutic agents.

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Salt stress adversely influences growth, development, and productivity in plants, resulting in a limitation on agriculture production worldwide. Therefore, this study aimed to investigate the effect of four different salts, i.e., NaCl, KCl, MgSO4, and CaCl2, applied at various concentrations of 0, 12.5, 25, 50, and 100 mM on the physico-chemical properties and essential oil composition of M. longifolia. After 45 days of transplantation, the plants were irrigated at different salinities at 4-day intervals for 60 days. The resulting data revealed a significant reduction in plant height, number of branches, biomass, chlorophyll content, and relative water content with rising concentrations of NaCl, KCl, and CaCl2. However, MgSO4 poses fewer toxic effects than other salts. Proline concentration, electrolyte leakage, and DPPH inhibition (%) increase with increasing salt concentrations. At lower-level salt conditions, we had a higher essential oil yield, and GC–MS analysis reported 36 compounds in which (−)-carvone and D-limonene covered the most area by 22%–50% and 45%–74%, respectively. The expression analyzed by qRT-PCR of synthetic Limonene (LS) and Carvone (ISPD) synthetic genes has synergistic and antagonistic relationships in response to salt treatments. To conclude, it can be said that lower levels of salt enhanced the production of essential oil in M. longifolia, which may provide future benefits commercially and medicinally. In addition to this, salt stress also resulted in the emergence of novel compounds in essential oils, for which future strategies are needed to identify the importance of these compounds in M. longifolia.