The Genus Gracilaria (Gracilariales, Rhodophyta) has compressed, cylindrical, fleshy, or succulent thallus that contains a wide variety of secondary metabolites, like agarans, lipids, steroids, mycosporine-like amino acids (MAAs), diterpenes, phenolic acids, sulfonic acids, bromophenols, heterosides, oxylipins, and xanthoproteins. Several of these metabolites are biologically active and particularly interested in pharmaceutical and nutraceutical applications. This review provides a comprehensive account of studies conducted on Gracilaria species demonstrating their cytotoxic, antioxidant, anticancer, antibacterial, anti-viral, antifungal, antidiabetic, and anti-inflammatory activities. We tried to elaborate the possible signaling pathways such as the NF-κB pathway, JAK–STAT pathway, apoptotic pathway, and Nrf-2-Keap1-ARE pathway, followed by Gracilaria secondary metabolites to suppress oxidative stress, inflammatory response, and inducing apoptosis, thereby treating various ailments. Improvements in biotechnological applications have enabled it to utilize and characterize the mechanisms through which Gracilaria modulate anticancer, anti-inflammatory, and apoptotic responses. However, a combination of therapies and clinical trials is needed for further research.

Recently, many studies have revealed the association between environmental stresses and skin disorders. Skin protects the inner body organs as a first line of defence against various environmental detriments. The physical, chemical, biological, and environmental stresses and internal factors, including reactive oxygen species, can lead to skin aging, laxity, wrinkles, dryness, and coarse texture. Therefore, utilizing naturally occurring bioactive phytochemicals has increased in recent years because of advancements in green technology, and new extraction techniques have made their use more compatible, enabling sustainable development. Alga, both macroalgae and microalgae are photosynthetic organisms that are highly exploited in food, feed, pharmaceuticals, nutraceutical, and cosmetic industries. Algae widely synthesize primary and secondary bioactive metabolites such as polysaccharides, vitamins, flavonoids, carotenoids, pigments, phenolic, and mycosporine-like amino acids, etc. Many cosmetic formulations use algal bioactive metabolites or algal cells as a moisturizer, texture-enhancing agents, anti-wrinkle agents, whitening agents, sunscreen, anti-cellulite, thickening agents, and also for hair care. The current review focuses on a better understanding and recent advancements in the application of algal extract and its biomass in a cosmetic formulation. It also briefly describes the current market scenario, challenges, and future prospectus of algae-based cosmetic products.

In recent years, nanotechnology has fascinated the scientific community due to its application in diverse fields such as medical, electrical and agricultural practices. The nanoparticle with size ranging between 1 and 100 nm is the essence of nanotechnology. Nanoparticles (NPs) exhibit amplified properties such as large surface area, stability and high reactivity due to their small size. These particles are prepared by physical, chemical and biological means. Due to some limitations in physical and chemical modes, biological modes are considered as a more reliable tool for NP synthesis because it is eco-friendly and cost-effective besides the ubiquitous nature of microbes. NPs can be synthesized by fungi, algae, viruses and bacteria. Bio-fabrication of nanoparticles has immense importance as a more decisive, defensible, prudent and eco-friendly method. This chapter emphasizes on the green synthesis of nanoparticles using microorganisms.

The present study focused on the antiproliferative effect of methanolic extracts of Ulva paschima (MEUP) on lung cancer cell lines A549 and H1299. The superoxide dismutase, catalase and glutathione reductase activities in MEUP were assayed. The intracellular reactive oxygen species, antioxidant potential, mitochondrial membrane potential and cell proliferation ability were also determined using standard methods while the extracts were analysed by GCMS. The study showed that MEUP had selective antiproliferative effect on cancer cell lines with IC50 0.187 +/- 0.120 mu g mu L-1 for A549 and 0.130 +/- 0.031 mu g mu L-1 for H1299 cells as determined by 3-(4,5-dimethylthiazol-2-cyl)-2,5-diphenyltetrazolium bromide (MTT) assay. MEUP induced oxidative stress in dose-dependent manner as measured by dihydro-ethidium (DHE) and 2 ',7 '-dichloro-dihydro-fluorescein diacetate (H2DCFDA) assays. Due to the induced oxidative stress by MEUP treatment, a rise in intracellular levels of antioxidant enzymes (glutathione reductase, superoxide dismutase, and catalase) was observed. A dose-dependent depolarization of mitochondrial membrane potential by 38% for A549 and 41% for H1299 cell lines was observed. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was 61.69% as compared to the ascorbic acid with EC50 of 176.7 +/- 0.09 mu g mL-1. GC-MS analysis of MEUP showed the presence of 1-dodecanol, 5-eicosene, neophytadiene, stearic acid, lauric acid, hexadecanoic acid, margaric acid, linoleic acid, L-alpha-terpineol, oleic acid, 9-octadecenamide, myristic acid and phytol known for their anticancerous properties. The phytochemical profile was evaluated for potential for serving as novel anticancer drug candidates.

The present study was aimed to assess the methanolic extracts of Gracilaria corticata and G. foliifera for anti-proliferative and anti-oxidant potency against breast cancer cell line MDA-MB-231. The antitumor activity of G. corticata methanolic extract (GCME) and G. foliifera methanolic extract (GFME) against MDA-MB-231 cells was assessed by 3-(4,5-dimethylthiazol-2-cyl)-2,5-diphenyltetrazolium bromide (MTT) assay. The extracts decreased cell viability of MDA-MB-231 cells with an estimated half-maximal inhibitory concentration (IC50) of 0.18 ± 1 and 0.078 ± 1 for GFMEs; and 0.116 ± 1 and 0.107 ± 1 for GCMEs. GCME significantly increased ROS level after 48 h of treatment and decreased glutathione (GSH) level (p<0.01) in a dose-and time-response manner. Intracellular ROS in MDA-MB-231 cells was determined by staining with fluorogenic agent 2',7'-dichloro-dihydrofluorescein diacetate (H2DCFDA). The mitochondrial membrane potential (Δψm)) disruption of GFME and GCME treated cells were maximum at 0.078 and 0.107 μg μL-1 (p<0.005). G. foliifera showed significantly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (78.6%) as compared to G. corticata(68.3%). This study also explored the phytochemical constituents of GFME and GCME such as hexadecanoic acid, methyl ester and cholesta-4,6-dien-3-ol, (3 beta), through GC-MS analysis.

The present study was aimed to assess the methanolic extracts of Gracilaria corticata and G. foliifera for anti-proliferative and anti-oxidant potency against breast cancer cell line MDA-MB-231. The antitumor activity of G. corticata methanolic extract (GCME) and G. foliifera methanolic extract (GFME) against MDA-MB-231 cells was assessed by 3-(4,5-dimethylthiazol-2-cyl)-2,5-diphenyltetrazolium bromide (MTT) assay. The extracts decreased cell viability of MDA-MB-231 cells with an estimated half-maximal inhibitory concentration (IC50) of 0.18 +/- 1 and 0.078 +/- 1 for GFMEs; and 0.116 +/- 1 and 0.107 +/- 1 for GCMEs. GCME significantly increased ROS level after 48 h of treatment and decreased glutathione (GSH) level (p<0.01) in a dose-and time-response manner. Intracellular ROS in MDA-MB-231 cells was determined by staining with fluorogenic agent 2 ',7 '-dichloro-dihydrofluorescein diacetate (H2DCFDA). The mitochondrial membrane potential (Delta psi m) disruption of GFME and GCME treated cells were maximum at 0.078 and 0.107 mu g mu L-1 (p<0.005). G. foliifera showed significantly higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (78.6%) as compared to G. corticata (68.3%). This study also explored the phytochemical constituents of GFME and GCME such as hexadecanoic acid, methyl ester and cholesta-4,6-dien-3-ol, (3 beta), through GC-MS analysis.

Oxidative stress originates from an elevated intracellular level of free oxygen radicals that cause lipid peroxidation, protein denaturation, DNA hydroxylation, and apoptosis, ultimately impairing cell viability. Antioxidants scavenge free radicals and reduce oxidative stress, which further helps to prevent cellular damage. Medicinal plants, fruits, and spices are the primary sources of antioxidants from time immemorial. In contrast to plants, microorganisms can be used as a source of antioxidants with the advantage of fast growth under controlled conditions. Further, microbe-based antioxidants are nontoxic, noncarcinogenic, and biodegradable as compared to synthetic antioxidants. The present review aims to summarize the current state of the research on the antioxidant activity of microorganisms including actinomycetes, bacteria, fungi, protozoa, microalgae, and yeast, which produce a variety of antioxidant compounds, i.e., carotenoids, polyphenols, vitamins, and sterol, etc. Special emphasis is given to the mechanisms and signaling pathways followed by antioxidants to scavenge Reactive Oxygen Species (ROS), especially for those antioxidant compounds that have been scarcely investigated so far.

Microorganisms including actinomycetes, archaea, bacteria, fungi, yeast, and micro algae are the auspicious source of vital bioactive compounds. In this review, the existing state of the art re-garding antimicrobial molecules from microorganisms has been summarized. The potential an-timicrobial compounds from actinomycetes, particularly Streptomyces sp.; archaea; fungi including endophytic and marine-derived fungi, mushroom; yeast, and microalgae were briefly described. Furthermore, this review briefly summarized the activity and mode of action of bacteriocins, a ribosomally synthesized antimicrobial peptides product of Eurotium sp., Streptomyces parvulus, S. thermophiles, Lactococcus lactis, etc. Bacteriocins have inherent properties such as targeting multi-ple-drug resistant pathogens, which allows them to be considered next-generation antibiotics. Similarly, Glarea lozoyensis derived antifungal lipohexpeptides i.e., pneumocandins, inhibits 1,3-β-glucan synthase of the fungal cell wall and acts as a precursor for the synthesis of caspo-fungin, is also elaborated. In conclusion, this review highlights the possibility of using microor-ganisms as an antimicrobial resource for biotechnological, nutraceutical, and pharmaceutical ap-plications. However, more investigations are still required to separate, purify, and characterize these bioactive compounds and transfer these primary drugs into clinically approved antibiotics.

India harbors the wealthiest biodiversity of mangroves, yet the utilization of sequence-based DNA barcodes for the characterization of mangrove diversity from the Indian coastal region is needed to be explored. In the present study, we assessed DNA barcode-based phylogenetics of mangroves from Sundarbans Delta and Kerala at the ITS locus of the nuclear genome. The phylogenetic analysis was performed using Bayesian inference, which proved to resolve the evolutionary affinities effectively. Our study presents mangroves’ systematic assessment with total 6 DNA sequences generated from 5 genera, and the first DNA barcode of Volkameria inermis and Avicennia marina from Payyanur Kerala, Avicennia alba and Suaeda maritima from the Sundarbans Delta was reported from ITS locus. The phylogenetic assessment confirmed that Avicennia belong s to the family Acanthaceae and placed the Volkameria inermis from Payyanur and Clerodendrum eriophyllum under the same monophyletic clade.

Arctic region is at the forefront of climate crisis; this is where the planet is warming maximally and the effects of climate change are most obvious. In this review, we introduce the topic in broader perspective by discussing first on why Arctic biodiversity matters, and scientific evidences for a changing Arctic biodiversity due to climate change. The Arctic then dwells into the current status of Arctic biodiversity covering species diversity and its conservation status with an emphasis on species important for bioprospecting. Subsequently, threats to Arctic biodiversity will be reviewed including climate change, shipping, oil exploration, overfishing, and overharvesting. This essay would then further deliberate why Arctic matters to India in particular. Himadri—Indian research station at Svalbard, Norway—will be briefed followed by an overview of Svalbard Global Seed Vault and why signing a pact with this international facility would benefit the country. The essay concludes with final thoughts and way forward including strategies to minimize Arctic biodiversity loss, UN SDGs (Ssustainable Ddevelopment Ggoals), and climate action.

Microorganisms including actinomycetes, archaea, bacteria, fungi, yeast, and microalgae are an auspicious source of vital bioactive compounds. In this review, the existing research regarding antimicrobial molecules from microorganisms is summarized. The potential antimicrobial compounds from actinomycetes, particularly Streptomyces spp.; archaea; fungi including endophytic, filamentous, and marine-derived fungi, mushroom; and microalgae are briefly described. Furthermore, this review briefly summarizes bacteriocins, halocins, sulfolobicin, etc., that target multiple-drug resistant pathogens and considers next-generation antibiotics. This review highlights the possibility of using microorganisms as an antimicrobial resource for biotechnological, nutraceutical, and pharmaceutical applications. However, more investigations are required to isolate, separate, purify, and characterize these bioactive compounds and transfer these primary drugs into clinically approved antibiotics.

The chemokine receptor 7 is a G-protein coupled, receptors coordinates the migration of cancer cells towards CCL19 and CCL21 constitutively expressed lymphatic organs. Chemokine receptor 7 facilitates cancer progression by generating new lymphatic vessels that serve as conduits for tumor dissemination to lymph nodes. In this context, chemokine receptor 7 inhibitor recently caught an attention for cancer cell growth inhibitor. The 3-D crystalline structure of chemokine receptor 7 not available in protein data bank (PDB), first we predicted the 3-D structure of chemokine receptor 7 and then performed receptor-based molecular docking of chemokine receptor 7 against natural and marine compounds. Semiquantitative polymerase chain reaction (PCR) and quantitative real-time PCR were performed for mRNA expression of chemokine receptor 7 and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) used as internal control. The best-docked compounds have been selected for chemokine receptor 7 inhibitors by optimal energy value (Gscore), types of interactions, and conformations. CID6441009, 42607750, 72276, 6711419, 56835050, 65064, 23663412, 72277, 643668, 54679285 compound have a better binding energy −11.35, −10.51, −10.16, −9.98, −9.95, −9.86, −9.83, −9.57, −9.47, and −9.45 respectively against chemokine receptor 7. Protein–ligand interactions profile highlighted that amino acid Glu45, Lys50, Arg54, Lys57, Trp114, Met260, Glu205, Gln227, Gln276, and Asp309 involved in the hydrophobic, hydrogen bonding, and π-π stacking interactions play a central role at the active site. Moreover, treatment with the Epigallocatechin gallate led to down-regulation of mRNA expression of chemokine receptor 7 in HepG2 and PC3 cells. This molecular docking study recapitulates the docking free energy, protein—ligands interactions profile, pharmacokinetic, and the pharmacodynamic parameter of lead molecules, which are extremely helpful to improve the activity of natural and marine compounds against chemokine receptor 7.