A comprehensive review on natural occurrence, synthesis and biological activities of glycolipids.

Glycolipids are ubiquitous and biologically important molecules and are involved in diverse biological functions and exhibit biosurfactant applications due to their surface-active and biodegradability properties. Despite showing a wide range of biological functions, not enough commercial exploitation has been taken place. Possible reasons for this could be the lack of focus or commercially viable processes for isolation/purification, as these glycolipids are found to be complex mixtures in their respective natural sources. Keeping these complexities in view, in this review, we focused on natural occurrences, including plants, marine micro algae, microorganisms, and salient features of various chemical methods, including glycosylation methods for the synthesis of different types of glycolipids. Further, this review significantly summarises the biological evaluation of a diverse class of glycolipids isolated and/or synthesized either by partial or total synthesis.

New indenopyrazole linked oxadiazole conjugates as anti-pancreatic cancer agents: Design, synthesis, in silico studies including 3D-QSAR analysis.

To continue the quest of newer anticancer agents, herein a novel class of 1,4-Dihydroindenopyrazole linked oxadiazole conjugates 9(a-r) was designed, synthesized and experimented for their anti-proliferative activities against four different cancer cell lines (human) such as MDA MB-231 (breast), PANC-1 (pancreatic), MCF-7 (breast), and Caco-2 (Colorectal) by using MTT assay. Among the series compound 9h and 9 m demonstrated significant potency against the PANC-1 (human pancreatic cancer cells) with IC50 value 7.4 µM and 4.3 µM respectively. While compound 9 m was found to be equipotent to standard Gomitabine (IC50 = 4.2 µM). The detailed biological assays revealed S phase cell cycle arrest and their ability to propagate apoptosis by activating caspase 3 and 9 enzymes which was confirmed by Annexin-FITC assay and caspase assay. Moreover, docking study suggested their binding modes and interactions with caspase-3. In addition, in silico studies revealed that they exhibit good pharmacokinetics and drug likeliness properties. Furthermore, 3D-QSAR was carried out to achieve a pharmacophoric model with CoMFA (q2 = 0.631, r2 = 0.977) and CoMSIA (q2 = 0.686, r2 = 0.954) on PANC-1 cancer cells which were established, generated and validated to be reliable models for further design and optimization of newer molecules with enhanced anticancer activity.

Anti-hyperglycemic and genotoxic studies of 1-O-methyl chrysophanol, a new anthraquinone isolated from Amycolatopsis thermoflava strain SFMA-103.

The compound 1-O-methyl chrysophanol (OMC) which belongs to a class of hydroxyanthraquinones was isolated from Amycolatopsis thermoflava strain SFMA-103 and studied for their anti-diabetic properties. OMC was evaluated as an anti-diabetic agent based on in silico studies which initially predicted the binding energy with α-amylase (-188.81 KJ mol-1) and with α-glucosidase (70.53 KJ mol-1). Further, these results were validated based on enzyme inhibition assays where OMC demonstrated enzyme inhibitory activity towards α-amylase (IC50 3.4 mg mL-1) and α-glucosidase (IC50 38.49 µg mL-1). To confirm the anti-diabetic activity, in vivo studies (oral dose in Wistar rats) revealed that OMC inhibited significantly the increase in glucose concentration at 100 mg/kg as compared to starch control (p < 0.05). Further, to understand the safety of OMC as a therapeutic agent, the genotoxic analysis was performed in both in vitro Chinese Hamster Ovary cells (250, 500, and 1000 µM/mL) and in vivo Swiss albino mice (250, 500, and 1000 mg/kg). In vitro results showed that OMC concentration of up to 250 µM/mL did not elicit significant changes in CAs, MI, and MN counts in CHO cells. Similarly, in mice experiments (i.p. injection), no significant changes in CAs, MI, and MN induction were observed till 500 mg/kg of OMC when compared with chrysophanic acid (Cy) (200 mg/kg). In addition, mice that received the lowest dose of OMC (250 mg/kg) did not show any histological changes in liver, kidney, and heart. The study concluded that five times higher therapeutic dose (100 mg/kg) of OMC can be utilized against hyperglycemia with no genotoxic effects.

New imidazo[2,1-b]thiazole-based aryl hydrazones: unravelling their synthesis and antiproliferative and apoptosis-inducing potential.

Herein, we have designed and synthesized new imidazo[2,1-b]thiazole-based aryl hydrazones (9a-w) and evaluated their anti-proliferative potential against a panel of human cancer cell lines. Among the synthesized compounds, 9i and 9m elicited promising cytotoxicity against the breast cancer cell line MDA-MB-231 with IC50 values of 1.65 and 1.12 µM, respectively. Cell cycle analysis revealed that 9i and 9m significantly arrest MDA-MB-231 cells in the G0/G1 phase. In addition, detailed biological studies such as annexin V-FITC/propidium iodide, DCFH-DA, JC-1 and DAPI staining assays revealed that 9i and 9m triggered apoptosis in MDA-MB-213 cells. Overall, the current work demonstrated the cytotoxicity and apoptosis-inducing potential of 9i and 9m in breast cancer cells and suggested that they could be explored as promising antiproliferative leads in the future.

Chumacin-1 and Chumacin-2 from Pseudomonas aeruginosa strain CGK-KS-1 as novel quorum sensing signaling inhibitors for biocontrol of bacterial blight of rice.

The in vitro inhibition of quorum sensing signal, xanthan gum secretion, biofilm formation in different Xanthomonas pathovars and biological control of bacterial blight of rice by the two bioactive extrolites produced by Pseudomonas aeruginosa strain CGK-KS-1 were explored. These extrolites were extracted from Diaion HP-20 resin with methanol and purified by preparative-thin layer chromatography. Further, spectroscopic structural elucidation revealed the tentative identity of these extrolites to be (R,3E,5E,9Z,11E)-13-((3S,5R)-5-acetyl-2,6-dimethylheptan-3-yl)-10-hydroxy-4-methyl-1,8-diazabicyclo[9.3.1]pentadeca-3,5,9,11(15),13-pentaen-2-one and (R,3E,5E,8E,11E)-13-((3S,5R)-5-acetyl-2,6-dimethylheptan-3-yl)-4-methyl-1,8-diazabicyclo[9.3.1]pentadeca-3,5,8,11(15),13-pentaene-2,10-dione, named as Chumacin-1 and Chumacin-2, respectively. Antimicrobial assay showed Chumacin-1 and Chumacin-2 exhibited a strong in vitro growth inhibition against various Xanthomonas pathovars. Quorum sensing overlay assay using a reporter strain Chromobacterium violaceum strain CV026 showed that Chumacin-1 and Chumacin-2 inhibited quorum sensing signaling. The mechanistic studies revealed that these extrolites inhibited the production of quorum sensing signaling factor, cis-11-methyl-2-dodecenoic acid; suppressed the xanthan gum secretion and also inhibited the biofilms formed by various Xanthomonas pathovars. Both Chumacin-1 and Chumacin-2 showed ROS generation in the test Xanthomonas strains, resulting in in vitro cell membrane damage was revealed through CSLM and FE-SEM micrographs. Further, greenhouse experiments using Samba Mashuri (BPT-5204) revealed that seed treatment with Chumacin-1 and Chumacin-2 along with foliar spray groups showed up to ˜80% reduction in bacterial blight disease in rice. To the best of our knowledge, this is the first report on new quorum sensing inhibitors, Chumacin-1 and Chumacin-2 produced by Pseudomonas aeruginosa strain CGK-KS-1 exhibiting DSF inhibition activity in Xanthomonas oryzae pv. oryzae.

Design, synthesis, and antimicrobial evaluation of 1,4-dihydroindeno[1,2-c]pyrazole tethered carbohydrazide hybrids: exploring their in silico ADMET, ergosterol inhibition and ROS inducing potential.

A series of new 1,4-dihydroindeno[1,2-c]pyrazole tethered carbohydrazide hybrids (5a-u) were designed, synthesized and evaluated for their antimicrobial activity. Compounds 5d, 5g, 5j, 5k and 5q demonstrated significant activity against the entire panel of test pathogens. Further, compounds 5d and 5g exhibited significant anti-Candida activity. These potential hybrids (5d and 5g) also exhibited promising ergosterol biosynthesis inhibition against Candida albicans, which was further validated through molecular docking studies. Furthermore, compounds 5d and 5g caused intracellular ROS accumulation in C. albicans MTCC 3017 and were non-toxic to normal human lung cell line MRC5. In silico studies revealed that they demonstrated drug likeness and an appreciable pharmacokinetic profile. Overall, the findings demonstrate that 5d and 5g may be considered as promising leads for further development of new antifungal drugs.

An overview on the synthetic and medicinal perspectives of indenopyrazoles.

Indenopyrazole is emerging as one of the most promising and privileged scaffold in medicinal chemistry. This scaffold have been investigated for the development of novel derivatives and hybrids with other moieties and substituents exhibiting a wide range of medicinal properties like antimycobacterial, antipsychotic, antihypertensive, cannabinoid receptor affinity, anti-tumor, antimicrobial, etc. Furthermore, indenopyrazoles function as inhibitors in various mechanistic pathways which has been well established based on its anticancer potential. This review illustrates various synthetic strategies adopted and reveals the extensive significant biological properties of indenopyrazoles. Furthermore, ample scope is available for this scaffold which needs to be explored by medicinal chemists for the development of new potential drug candidates.

Phenazine-1-carboxamide functionalized mesoporous silica nanoparticles as antimicrobial coatings on silicone urethral catheters.

Microbial infections due to biofilms on medical implants can be prevented by antimicrobial coatings on biomaterial surfaces. Mesoporous silica nanoparticles (MSNPs) were synthesized via base-catalyzed sol-gel process at room temperature, functionalized with phenazine-1-carboxamide (PCN) and characterized by UV-visible, FT-IR, DLS, XRD spectroscopic techniques, SEM, TEM, TGA and BET analysis. Native MSNPs, PCN and PCN-MSNPs were evaluated for anti-Candida minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), Candida albicans (C. albicans) biofilms and C. albicans-Staphylococcus aureus (S. aureus) polymicrobial biofilm inhibition. PCN-MSNPs were four-fold effective (MIC 3.9 µg mL-1; 17.47 µM) and MFC (7.8 µg mL-1; 34.94 µM) as compared to pure PCN (MIC 15.6 µg mL-1; 69.88 µM) and MFC (31.2 µg mL-1; 139.76 µM). PCN-MSNPs inhibited in vitro C. albicans MTCC 227-S. aureus MTCC 96 biofilms at very low concentration (10 µg mL-1; 44.79 µM) as compared to pure PCN (40 µg mL-1; 179.18 µM). Mechanistic studies revealed that PCN induced intracellular ROS accumulation in C. albicans MTCC 227, S. aureus MTCC 96 and S. aureus MLS-16 MTCC 2940, reduction in total ergosterol content, membrane permeability, disruption of ionic homeostasis followed by Na+, K+ and Ca2+ leakage leading to cell death in C. albicans MTCC 227 as confirmed by confocal laser scanning micrographs. The silicone urethral catheters coated with PCN-MSNPs (500 µg mL-1; 2.23 mM) exhibited no formation of C. albicans MTCC 227 - S. aureus MTCC 96 and C. albicans MTCC 227 - S. aureus MLS -16 MTCC 2940 biofilms. This is the first report on PCN-MSNPs for use as antimicrobial coatings against microbial adhesion and biofilm formation on silicone urethral catheters.

Synthesis, antiproliferative and apoptosis induction potential activities of novel bis(indolyl)hydrazide-hydrazone derivatives.

In recent years, indole-indazolyl hydrazide-hydrazone derivatives with strong cell growth inhibition and apoptosis induction characteristics are being strongly screened for their cancer chemo-preventive potential. In the present study, N-methyl and N,N-dimethyl bis(indolyl)hydrazide-hydrazone analog derivatives were designed, synthesized and allowed to evaluate for their anti-proliferative and apoptosis induction potential against cervical (HeLa), breast (MCF-7 and MDA-MB-231) and lung (A549) cancer cell lines relative to normal HEK293 cells. The MTT assay in conjunction with mitochondrial potential assays and the trypan blue dye exclusion were employed to ascertain the effects of the derivatives on the cancer cells. Further, mechanistic studies were conducted on compound 14a to understand the biochemical mechanisms and functional interactions with various signaling pathways triggered in HeLa and MCF-7 cells. Compound 14a induced apoptosis via caspase independent pathway through the participation of mitogen-activated protein kinases (MAPK) such as extracellular signal related kinase (ERK) and p38 as well as p53 pathways. It originates the activation of pro-apoptotic proteins such as Bak and Mcl-1s and also strongly induced the generation of reactive oxygen species. In downstream signaling pathway, activated p53 protein interacted with MAPK pathways, including SAPK/c-Jun N-terminal protein kinase (JNK), p38 and ERK kinases resulting in apoptotic cell death. The involvement of MAPK cascades such as p38, ERK and p38 on compound 14a induced apoptotic cell death was evidenced by the fact that the inclusion of specific inhibitors of p38, ERK1/2 and JNK MAPK (SB2035809, PD98059 and SP600125) prevented the compound 14a towards induced apoptosis. The results clearly showed that MAP kinase cascades were crucial for apoptotic response in compound 14a induced cellular killing and were dependent on p53 activity. Based on the results, compound 14a was identified as a promising candidate for cancer therapeutics and these findings furnish a basis for further in vivo experiments on anti-proliferative activity.

Synthesis and biological evaluation of pyrazole linked benzothiazole-ß-naphthol derivatives as topoisomerase I inhibitors with DNA binding ability.

A series of new pyrazole linked benzothiazole-ß-naphthol derivatives were designed and synthesized using a simple, efficient and ecofriendly route under catalyst-free conditions in good to excellent yields. These derivatives were evaluated for their cytotoxicity on selected human cancer cell lines. Among those, the derivatives 4j, 4k and 4l exhibited considerable cytotoxicity with IC50 values ranging between 4.63 and 5.54 µM against human cervical cancer cells (HeLa). Structure activity relationship was elucidated by varying different substituents on benzothiazoles and pyrazoles. Further, flow cytometric analysis revealed that these derivatives induced cell cycle arrest in G2/M phase and spectroscopic studies such as UV-visible, fluorescence and circular dichroism studies showed that these derivatives exhibited good DNA binding affinity. Additionally, these derivatives can effectively inhibit the topoisomerase I activity. Viscosity studies and molecular docking studies demonstrated that the derivatives bind with the minor groove of the DNA.

Structural characterization and biological evaluation of Staphylosan (dimannooleate), a new glycolipid surfactant produced by a marine Staphylococcus saprophyticus SBPS-15.

Marine microbes have gained significant attention as potential biofactories for broad spectrum bioactive compounds. In the recent years, bioactive biosurfactants have warranted renewed interest from both environmental and clinical sectors as anti-biofilm agents due to their excellent properties of dispersing microbial biofilms. The present study explores a new glycolipid biosurfactant produced by a marine Staphylococcus saprophyticus exhibiting interesting biological activities. This glycolipid biosurfactant was purified and identified as Mannose-Mannose-Oleic acid (named as Staphylosan) based on the results of NMR, GC, GC-MS, MALDI-TOF-MS and tandem MS analysis. The surface tension and critical micelle concentration of purified Staphylosan was 30.9 mN m-1 and 24 mg L-1. Further, it showed promising biofilm inhibition and dislodging activities against a panel of profuse biofilm forming bacteria at both single and multi-species level which were isolated from boat hull biofilm environment such as Bacillus subtilis BHKH-7, Acinetobacter beijerinckii BHKH-11, Pseudomonas aeruginosa BHKH-19, Serratia liquefaciens BHKH-23, Marinobacter lipolyticus BHKH-31 and Micrococcus luteus BHKH-39. Moreover, it exhibited anionic charge and revealed non-toxicity towards brine shrimps, suggesting its environmental safety. This is a first report on Staphylosan, a multifunctional glycolipid surfactant from a marine Staphylococcus saprophyticus SBPS-15, exhibiting promising anti-biofilm activities and non-toxic in nature and thus finds possible potential use in many environmental applications especially under marine conditions.

Design, synthesis, in silico pharmacokinetics prediction and biological evaluation of 1,4-dihydroindeno[1,2-c]pyrazole chalcone as EGFR /Akt pathway inhibitors.

In an attempt to develop potent and selective anticancer agents, a series of 15 conjugates of 1,4-dihydroindeno[1,2-c]pyrazole chalcone (12a-o) were designed, synthesized and evaluated for their antiproliferative activity against MCF7, A549, MDA-MB-231, HCT116 and SKBR3 human cancer cell lines. Among them, 12h, 12l and 12m showed IC50 values: 3.82, 5.33 and 4.21 µM, respectively, on A549 cell with respect to the positive control, Erlotinib (IC50 value: 10.26 µM). Detailed biological assays showed accumulation of mitotic cells in G2/M phase. In addition, Western blot analysis and immunofluorescence study revealed inhibition of EGFR and Akt pathways. In silico computational studies were also carried out to predict the binding modes and pharmacokinetic parameters of these conjugates.

A novel templates of piperazinyl-1,2-dihydroquinoline-3-carboxylates: Synthesis, anti-microbial evaluation and molecular docking studies.

A series of piperazinyl-1,2-dihydroquinoline carboxylates were synthesized by the reaction of ethyl 4-chloro-1-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylates with various piperazines and their structures were confirmed by 1H NMR, 13C NMR, IR and mass spectral analysis. All the synthesized compounds were screened for their in vitro antimicrobial activities. Further, the in silico molecular docking studies of the active compounds was performed to explore the binding interactions between piperazinyl-1,2-dihydroquinoline carboxylate derivatives and the active site of the Staphylococcus aureus (CrtM) dehydrosqualene synthase (PDB ID: 2ZCQ). The docking studies revealed that the synthesized derivatives showed high binding energies and strong H-bond interactions with the dehydrosqualene synthase validating the observed antimicrobial activity data. Based on antimicrobial activity and docking studies, the compounds 9b and 10c were identified as promising antimicrobial lead molecules. This study might provide insights to identify new drug candidates that target the S. aureus virulence factor, dehydrosqualene synthase.

Synthesis and Bioevaluation of Quaternary Centered 3-hydroxy-3 (alkynyl)indolin-2-one Derivatives as Potential Cytotoxic Agents and Akt Kinase Inhibitors.

BACKGROUND: Alkynes are fundamental building blocks in synthetic chemistry with high pharmaceutical applications. Among the bioactive acetylenic molecules, propargylic alcohol is most important as almost all the marketed drugs contains quaternary centered propargylic alcohol functionality. OBJECTIVE: In this study we have synthesised and evaluated 3-hydroxy-3-ethynylindolin-2-one derivatives for in vitro cytotoxic activity. METHOD: An expeditious method for direct alkynylation of isatins (ketones) has been developed using tetrabutylammonium fluoride (TBAF) as a catalyst in THF solvent at room temperature under metal-free conditions. Furthermore, this method is an economically viable process that also compliments green aspects like being a ligand/metal free process under ambient conditions. This reaction tolerated a wide range of substrates with good to excellent yields (80-94%). RESULTS: The results showed that the synthesized compounds (4m, 4n and 4p) has the ability to inhibit Akt kinase activity with IC50 values ranging from 7.7 to 9.8 µM. CONCLUSION: All the 3-hydroxy-3-ethynylindolin-2-one derivatives were subjected for in vitro cytotoxic activity on five different cancer cell lines. Further, the synthesized compounds (4m, 4n and 4p) were evaluated for their ability to inhibit Akt kinase activity and exhibited good inhibition with IC50 values ranging from 7.7 to 9.8 µM..

Design, synthesis and biological evaluation of 1, 4-dihydro indeno[1,2-c] pyrazole linked oxindole analogues as potential anticancer agents targeting tubulin and inducing p53 dependent apoptosis.

A series of 1, 4-dihydroindeno-[1,2-c] pyrazole linked oxindole conjugates have been synthesized by using Knoevenagel condensation method and further evaluated for their antiproliferative activity against HeLa, A549 and MDA-MB-231 human cancer cell lines along with HEK-293 (normal human embryonic kidney cells). Among the derivatives, compounds 12a, 12b, and 12d showed excellent cytotoxicity with IC50 values ranging between 1.33 to 4.33 µM. Furthermore, detailed biological assays showed that there was accumulation of mitotic cells in G2/M phase, disruption of microtubule network and increase in the G2/M checkpoint proteins (Cyclin B1 and CDK1). Moreover, compound 12d with IC50 value of 1.33 µM showed significant upregulation of tumor suppressor proteins like p53, p21 and pro-apoptotic Bax. The molecular docking analysis demonstrated that these congeners occupy the colchicine binding pocket of the tubulin.

Potential antimicrobial agents from triazole-functionalized 2H-benzo[b][1,4]oxazin-3(4H)-ones.

A series of substituted triazole functionalized 2H-benzo[b][1,4]oxazin-3(4H)-ones were synthesized by employing click chemistry and further characterized based on 1H NMR, 13C NMR, IR and mass spectral studies. All the synthesized derivatives were screened for their in vitro antimicrobial activities. Further, molecular docking studies were accomplished to explore the binding interactions between 1,2,3-triazol-4-yl-2H-benzo[b][1,4]oxazin-3(4H)-one and the active site of Staphylococcus aureus (CrtM) dehydrosqualene synthase (PDB ID: 2ZCS). These docking studies revealed that the synthesized derivatives showed high binding energies and strong H-bond interactions with the dehydrosqualene synthase validating the observed antimicrobial activity data. Based on antimicrobial activity and docking studies, the compounds 9c, 9d and 9e were identified as promising antimicrobial leads.

Design, synthesis and biological evaluation of novel pyrazolochalcones as potential modulators of PI3K/Akt/mTOR pathway and inducers of apoptosis in breast cancer cells.

Cancer has been established as the "Emperor of all maladies". In recent years, medicinal chemistry has focused on identifying novel anti-cancer compounds; though discovery of these compounds appears to be a herculean task. In present study, we synthesized forty pyrazolochalcone conjugates and explored their cytotoxic activity against a panel of sixty cancer cell lines. Fifteen conjugates of the series showed excellent growth inhibition (13b-e, 13h-j, 14c-d, 15 a, 15 c-d, 16b, 16d and 18f; GI50 for MCF-7: 0.4-20 µM). Conjugates 13b, 13c, 13d, 16b and 14d were also evaluated for their cytotoxic activity in human breast cancer cell line (MCF-7). The promising candidates induced cell cycle arrest, mitochondrial membrane depolarization and apoptosis in MCF-7 cells at a 2 µM concentration. Furthermore, inhibition of PI3K/Akt/mTOR pathway-regulators such as PI3K, p-PI3K, p-AKT, and mTOR were observed; as well as upregulation of p-GSK3ß and tumor-suppressor protein, PTEN. Our study indicates that pyrazolochalcone conjugates could serve as potential leads in the development of tailored cancer therapeutics.

Biological evaluation of 3-hydroxybenzyl alcohol, an extrolite produced by Aspergillus nidulans strain KZR-132.

AIMS: The aim of the study was to purify and characterize a bioactive compound from Aspergillus nidulans strain KZR-132 and its biological evaluation. METHODS AND RESULTS: A bioactive extolite was purified from A. nidulans strain KZR-132, and its chemical structure was elucidated as 3-hydroxylbenzyl alcohol (3-HBA) based on 1 H and 13 C NMR, FT-IR and mass spectroscopic analysis. The antimicrobial efficacy of 3-HBA was established against Gram-positive, Gram-negative bacteria and different Candida strains. It also showed promising antibiofilm activity against various tested microbial strains. Reactive oxygen species induced by 3-HBA treatment on different Candida strains killed most of the cells and showed necrotic effect. It also exhibited dose-dependent antioxidant and anti-inflammatory activities. CONCLUSIONS: This bioactive extrolite produced by A. nidulans isolated from a niche habitat was demonstrated to possess significant biotechnological and pharmacological potential since it exhibited broad-spectrum antimicrobial and antibiofilm activities which are reported for the first time. SIGNIFICANCE AND IMPACT OF THE STUDY: The overall study demonstrates that 3-HBA produced by A. nidulansKZR-132 is a promising bioactive metabolite and possibly can function as a pharmacologically suitable broad-spectrum antimicrobial drug candidate against various dreaded human-related bacterial and fungal pathogens.

Synthesis and in vitro antioxidant and antimicrobial studies of novel structured phosphatidylcholines with phenolic acids.

Novel phenoylated phosphatidylcholines were synthesized from 1,2-dipalmitoyl phosphatidylcholine/egg 1,2-diacyl phosphatidylcholine and phenolic acids such as ferulic, sinapic, vanillic and syringic acids. The structures of phenoylated phosphatidylcholines were confirmed by spectral analysis. 2-acyl-1-lyso phosphatidylcholine was synthesized from phosphatidylcholine via regioselective enzymatic hydrolysis and was reacted with hydroxyl protected phenolic acids to produce corresponding phenoylated phosphatidylcholines in 48-56% yields. Deprotection of protected phenoylated phosphatidylcholines resulted in phenoylated phosphatidylcholines in 87-94% yields. The prepared compounds were evaluated for their preliminary in vitro antimicrobial and antioxidant activities. Among the active derivatives, compound 1-(4-hydroxy-3,5-dimethoxy) cinnamoyl-2-acyl-sn-glycero-3-phosphocholine exhibited excellent antioxidant activity with EC50 value of 16.43µg/mL. Compounds 1-(4-hydroxy-3-methoxy) cinnamoyl-2-acyl-sn-glycero-3-phosphocholine and 1-(4-hydroxy-3,5-dimethoxy) cinnamoyl-2-palmitoyl-sn-glycero-3-phosphocholine exhibited good antioxidant activity with EC50 values of 36.05 and 33.35µg/mL respectively. Compound 1-(4-hydroxy-3-methoxy) cinnamoyl-2-palmitoyl-sn-glycero-3-phosphocholine exhibited good antibacterial activity against Klebsiella planticola with MIC of 15.6µg/mL and compound 1-(4-hydroxy-3-methoxy) benzoyl-2-acyl-sn-glycero-3-phosphocholine exhibited good antifungal activity against Candida albicans with MIC of 15.6µg/mL.

Aneurinifactin, a new lipopeptide biosurfactant produced by a marine Aneurinibacillus aneurinilyticus SBP-11 isolated from Gulf of Mannar: Purification, characterization and its biological evaluation.

Biosurfactants are microbial-derived amphiphilic molecules having hydrophobic and hydrophilic moieties produced by bacteria, fungi, yeasts and algae and are extracellular or cell wall-associated compounds. In an ongoing survey for bioactive microbial metabolites from microbes isolated from diverse ecological niches, a new lipopeptide biosurfactant was identified from a marine bacterium; Aneurinibacillus aneurinilyticus strain SBP-11, which was isolated from a marine diversity hotspot, Gulf of Mannar, India. A new lipopeptide biosurfactant was purified and characterized based on TLC, FT-IR, NMR, GC-MS, HPLC, MALDI-TOF-MS and tandem MS analysis as Stearic acid-Thr-Tyr-Val-Ser-Tyr-Thr (named as Aneurinifactin). The critical micelle concentration of Aneurinifactin was 26mgL-1 at a surface tension of 26mNm-1. Further, the biosurfactant showed stable emulsification at a wide range of pH (2-9) and temperature up to 80°C. Aneurinifactin showed promising antimicrobial activity and concentration dependent efficient oil recovery. This is the first report on Aneurinifactin, a lipopeptide biosurfactant produced by a marine A. aneurinilyticus SBP-11, which could be explored as a promising candidate for use in various biomedical and industrial applications.