Synthesis and biological evaluation of ricinoleic acid-based lipoamino acid derivatives.

A series of novel ricinoleic acid based lipoamino acid derivatives were synthesized from (Z)-methyl-12-aminooctadec-9-enoate and different l-amino acids (glycine, alanine, phenyl alanine, valine, leucine, isoleucine, proline and tryptophan). The structures of all the prepared compounds were characterized by 1H NMR, 13C NMR and mass spectral studies. The title compounds were evaluated for their antimicrobial and anti-biofilm activities. Among all the derivatives, compound 7a (Z)-methyl-12-(2-aminoacetamido)octadec-9-enoate exhibited promising antibacterial activity (MIC, 3.9-7.8µg/mL) and compounds 7b (Z)-methyl 12-(2-aminopropanamido)octadec-9-enoate and 7g (Z)-methyl-12-(pyrrolidine-2-carboxamido)octadec-9-enoate exhibited moderate activity (MIC, 7.8-31.2µg/mL) selectively against four different Gram-positive bacterial strains such as Staphylococcus aureus MTCC 96, Bacillus subtilis MTCC 121, S. aureus MLS-16 MTCC 2940, Micrococcus luteus MTCC 2470. These compounds also exhibited excellent antifungal activity against studied fungal strains. Further, the compounds 7a, 7b and 7g were also screened for anti-biofilm activity. Among these lipoamino acid derivatives, compound 7a exhibited good anti-biofilm activity (IC50, 1.9-4.1µg/mL) against four Gram-positive bacterial strains.

Synthesis, antimicrobial and anti-biofilm activities of novel Schiff base analogues derived from methyl-12-aminooctadec-9-enoate.

A novel library of Schiff base analogues (5a-q) were synthesized by the condensation of methyl-12-aminooctadec-9-enoate and different substituted aromatic aldehydes. The synthesized compounds were thoroughly characterized by spectroscopic techniques (FT-IR, (1)H NMR, (13)C NMR, ESI-MS and HRMS). The Schiff base analogues with different substitutions were screened for in vitro antibacterial activity against 7 different bacterial strains. Among these, the compounds with electron withdrawing substituent, namely chlorine (5a) and electron donating substituents, namely hydroxy (5 n) and methoxy (5 o), were found to exhibit excellent to good antimicrobial activities (MIC value 9-18 µM) against Staphylococcus aureus MTCC 96, Staphylococcus aureus MLS-16 MTCC 2940 and Bacillus subtilis MTCC 121. The products were also screened for anti-biofilm and MBC (Minimum Bactericidal Concentration) activities which exhibited promising activities.

Studies on lipid profiles and fatty acid composition of roe from rohu (Labeo rohita) and murrel (Channa striatus).

The lipid profiles and fatty acid composition of roes from two common fresh water fish viz., rohu (Labeo rohita) and murrel (Channa striatus) have been studied. The dehydrated fish egg was ground to fine powder and extracted with chloroform/methanol (2:1, v/v) to recover the total lipid in 20.2 and 22.7% on dry weight basis. The fat free meal was found to contain 70 and 58% protein in rohu and murrel, respectively. The total lipids were separated into neutral lipids, glycolipids and phospholipids using silica gel column chromatography and found to be 43.8, 72.9% neutral lipids; 12.7, 9.4% glycolipids and 43.5, 17.7% phospholipids in rohu and murrel roes, respectively. The fatty acid compositions of all lipid classes were analysed by GC and GC-MS. Among the saturated fatty acids, hexadecanoic acid (16:0) was found to be 30.2 and 30.4% respectively in rohu and murrel total lipid. n-3 Fatty acids namely eicosapentaenoic acid (20:5, EPA) was observed to an extent of 1.5 and 0.6% and docosahexaenoic acid (22:6, DHA) to an extent of 11.8 and 6.1% respectively in rohu and murrel total lipids. Stearic acid (18:0) was also seen at 12.2 and 6% respectively in rohu and murrel lipids. The fatty acid composition was found to be almost similar in all the lipid classes. The study indicated that rohu and murrel fish egg lipids are good sources for polyunsaturated n-3 fatty acids.

Phospholipase-mediated preparation of 1-ricinoleoyl-2-acyl-sn-glycero-3-phosphocholine from soya and egg phosphatidylcholine.

1-Ricinoleoyl-2-acyl-sn-glycero-3-phosphocholine was prepared by incorporating ricinoleic acid completely in the sn-1 position of egg and soya phosphatidylcholine (PC) using immobilized phospholipase A(1) as the catalyst. The optimum reaction conditions for maximum incorporation of ricinoleic acid into PC through transesterification were 10% (w/w) immobilized enzyme (116 mg), a 1:5 mol ratio of PC (soya, 387 mg; egg, 384 mg) to methyl ricinoleate (780 mg) at 50 degrees C for 24 h in hexane.