The unicellular marine alga Dunaliella salina is a most interesting green cell factory for the production of carotenes and lipids under extreme environment conditions. However, the culture conditions and their productivity are the major challenges faced by researchers which still need to be addressed. In this study, we investigated the effect of bicarbonate amendment on biomass, photosynthetic activity, biochemical constituents, nutrient uptake and antioxidant response of D. salina during macronutrient deficit conditions (N⁻, P⁻ and S⁻). Under nutrient deficit conditions, addition of sodium bicarbonate (100 mM) significantly increased the biomass, carotenoids including β-carotene and lutein, lipid, and fatty acid content with concurrent enhancement of the activities of nutrient assimilatory and carbonic anhydrase enzymes. Maximum accumulation of carotenoid especially β-carotene (192.8 ± 2.11 µg/100 mg) and lipids (53.9%) was observed on addition of bicarbonate during nitrate deficiency compared to phosphate and sulphate deficiency. Supplementation of bicarbonate reduced the oxidative stress caused by ROS, lowered lipid peroxidation damage and improved the activities of antioxidant enzymes (SOD, CAT and APX) in D. salina cultures under nutrient stress.

Carbon nanodots (CNDs) are advanced nanomaterials with a size of 2–10 nm and are considered zero-dimensional carbonaceous materials. CNDs have received great attention in the area of cancer theranostics. The majority of review articles have shown the improvement of CNDs for use in cancer therapy and bioimaging applications. However, there is a minimal number of consolidated studies on the currently developed doped CNDs that are used in various ways in cancer therapies. Hence, in this review, we discuss the current developments in different types of heteroatom elements/metal ion-doped CNDs along with their preparations, physicochemical and biological properties, multimodal-imaging, and emerging applications in image-guided photodynamic therapies for cancer.

Dunaliella salina is a photosynthetic cell factory used for the commercial production of food additives, cattle stock feed and cosmetics as well as active ingredients for pharmaceutical industries. The investigation of the in vivo antitumor activity of D. salina lyophilized powder (DSLP) against 7,12-dimethylbenz(a)anthracene (DMBA) induced mammary carcinogenesis in female Wistar rats indicated a dose-dependent effect of DSLP. We studied the effect of DSLP at two different dosages of 500 and 1000 mg per kg bw on DMBA induced mammary cancer in rats by measuring the status of antioxidant enzymes, phase I and phase II detoxification enzymes, lipid peroxidation, and glycoconjugated proteins and by investigating the expression pattern of cell proliferation (Ki-67), hormonal receptor (ER, PR and HER2) status by immunohistochemical analysis, and apoptotic (caspase-3 and -9) and pro-inflammatory (COX-2) markers by colorimetric analysis. After 16 weeks of the study, we observed 100% tumor formation (including high tumor incidence and tumor volume) and a significant increase in the level of hormonal receptors, cell proliferation, and pro-inflammatory and apoptosis markers in tumor-bearing animals compared to the control. The oral administration of DSLP (1000 mg per kg bw) to the DMBA treated animals showed up to 83.4% reduction of tumors and effectively restored the levels of biochemical markers in the mammary tissues in addition to the downregulation of the expression of molecular markers. In conclusion, DSLP was found to show a chemopreventive effect against breast cancer induced in rats through the suppression of cell proliferation and the induction of apoptosis.

Enzymes find their applications in various industries, due to their error free conversion of substrate into product. Tannase is an enzyme used by various industries for degradation of tannin. Biochemical characterization of a specific enzyme from one organism to other is one of the ways to search for enzymes with better traits for industrial applications. Here, tannase encoding gene from Staphylococcus lugdunensis was cloned and suitability of the enzyme in various conditions was analysed to find its application in various industry. The recombinant protein was expressed with 6× His tag and purified using nickel affinity beads. The enzyme was purified up to homogeneity, with approximate molecular weight of 66 kDa. Purified tannase exhibited specific activity of about 716 U/mg. Optimum enzyme activity was found to be 40 °C at pH 7.0. Biochemical characterization revealed; metal ions such as Zn2+, Fe2+, Fe3+ and Mn2+ inhibited tannase activity, and SDS at lower concentration, increased tannase activity. Non polar organic solvents increased the tannase activity and polar solvents inhibited the tannase activity. Tannase immobilization studies show protection of the enzyme under wide range of pH and temperature. Also in this study we report a method for recovery and repeated use of the tannase.

The potentiality of nanomedicine in the cancer treatment being widely recognized in the recent years. In the present investigation, the synergistic effects of chitosan-modified selenium nanoparticles loaded with paclitaxel (PTX-chit-SeNPs) were studied. These selenium nanoparticles were tested for drug release analysis at a pH of 7.4 and 5.5, and further characterized using FTIR, DLS, zeta potential, and TEM to confirm their morphology, and the encapsulation of the drug was carried out using UPLC analysis. Quantitative evaluation of anti-cancer properties was performed via MTT analysis, apoptosis, gene expression analysis, cell cycle arrest, and over-production of ROS. The unique combination of phytochemicals from the seed extract, chitosan, paclitaxel, and selenium nanoparticles can be effectively utilized to combat cancerous cells. The production of the nanosystem has been demonstrated to be cost-effective and have unique characteristics, and can be utilized for improving future diagnostic approaches.