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At least 19 recordsLinked to original sources
PubMed2004

Mixture additives inhibit the dermal permeation of the fatty acid, ricinoleic acid.

Ricinoleic acid (RA) like many of the ingredients in machine cutting fluids and other industrial formulations are potential dermal irritants, yet very little is known about its permeability in skin. 3H-ricinoleic acid mixtures were formulated with three commonly used cutting fluid additives; namely, triazine (TRI), linear alkylbenzene sulfonate (LAS), and triethanolamine (TEA) and topically applied to inert silastic membranes and porcine skin in vitro as aqueous mineral oil (MO) or polyethylene glycol (PEG) mixtures. These additives significantly decreased ricinoleic acid partitioning from the formulation into the stratum corneum (SC) in PEG-based mixtures. Except for LAS, all other additives produced a more basic formulation (pH = 9.3-10.3). In silastic membranes and porcine skin, individual additives or combination of additives significantly reduced ricinoleic permeability. This trend in ricinoleic acid disposition in both membranes suggests that the mixture interaction is more physicochemical in nature and probably not related to the chemical-induced changes in the biological membrane as may be assumed with topical exposures to potentially irritant formulations.

Alkanesulfonic Acids↗
PubMed2004

Diversity of oleic acid, ricinoleic acid and linoleic acid conversions among Pseudomonas aeruginosa strains.

Sixteen Pseudomonas aeruginosa strains, including patent strain NRRL B-18602, three recent isolates from composted materials amended with ricinoleic acid, and 12 randomly selected from the holdings of the ARS Culture Collection, were examined for their fatty acid converting abilities. The study examined the bioconversion of oleic acid to 7,10-dihydroxy-8( E)-octadecenoic acid (DOD) and ricinoleic acid to 7,10,12-trihydroxy-8( E)-octadecenoic acid (TOD). A new DOD-like compound from linoleic acid was observed. All strains except NRRL B-247 exhibited varying levels of DOD production. NRRL B-1000, NRRL B-18602 and NRRL B-23258 with yields up to 84% were among the best DOD producers. TOD production generally paralleled DOD production at a relatively lower yield of up to 15%. Strains NRRL B-1000 and NRRL B-23260 were the best TOD producers. A DOD-like product in low yields was obtained from linoleic acid. The fatty acid bioconversion capability was related neither to growth rate nor to variation in the greenish pigmentation of the strains. Production of significant quantities of DOD and TOD from oleic and ricinoleic acids, respectively, appeared to be a characteristic trait of P. aeruginosa strains. A number of highly effective strains for DOD production were identified.

Culture Media↗
PubMed2006

Poly(sebacic acid-co-ricinoleic acid) biodegradable injectable in situ gelling polymer.

The investigated polymers, poly(sebacic acid-co-ricinoleic acid) containing > or =70% ricinoleic acid, may be injected via a 22 gauge needle and become gel upon contact with aqueous medium, both in vitro and in vivo. Various properties of the polymers including viscosity, thermal analysis, and in vivo behavior, before and after exposure to aqueous medium, were determined. These polymers were observed using scanning electron microscopy (SEM) at dry and wet states. It was found that the viscosity and melting temperature of P(SA:RA) increased after exposure to buffer. The viscosity at 37 degrees C of P(SA:RA)3:7 had the highest increase: from 4200 cP before to 8940 cP after exposure to buffer; in the case of P(SA:RA)25:75 before exposure to buffer the viscosity was 1150 cP while after it raised to 3200 cP. The viscosity of P(SA:RA)2:8 also increased from 400 cP before exposure to buffer to 1000 cP after. On the other hand polymer without sebacic acid, (poly(ricinoleic acid)), did not show gelation properties. Thermal analysis also showed an increase in the melting point of the polymers exposed to the aqueous medium during the first 24 h of incubation. Images obtained by SEM showed formation of a three-dimensional network in polymers exposed to buffers. When injected into animals, P(SA:RA) forms a solid implant in the injection site already at 8 h postinjection.

Animals↗
PubMed2005

Poly(sebacic acid-co-ricinoleic acid) biodegradable carrier for paclitaxel--effect of additives.

Injectable polymeric formulation for paclitaxel was studied. Poly ricinoleic acid and sebacic acid were synthesized. The effect of additives on the viscosity of polymer, paclitaxel release, and polymer degradation was investigated both in vitro and in vivo. Additives that were used in this study were ricinoleic acid, phospholipid, PEG 400, and PEG 2000. Addition of 20% ricinoleic acid to P(SA:RA)3:7 liquefied the formulation and allowed injection of the formulation containing paclitaxel via a 22-G needle at room temperature with no effect on paclitaxel release rate. Addition of PEG 400, PEG 2000, and phospholipid to the formulation did not affect the paclitaxel release from the formulation. The degradation of modified formulations with paclitaxel and additives was examined in vitro and by subcutaneous injection of liquid formulations to the backspace via a 22-G needle into seven groups of four C3H mice. In vivo formulations with additives (20% ricinoleic acid and PEG or phospholipid) and 5% paclitaxel content degraded faster than the formulation with only 20% ricinoleic acid and the same paclitaxel content: 51% and 54% versus 43%. The slowest degradation (26% in 1 week) was of the formulation containing 10% paclitaxel. The release rate in vivo was affected by the paclitaxel content; the higher the content, the slower was the release. By using additives, we could adjust the physical characteristics of the surgical paste while maintaining a desirable system for sustained paclitaxel release.

Animals↗
PubMed2004

Poly(sebacic acid-co-ricinoleic acid) biodegradable carrier for paclitaxel: in vitro release and in vivo toxicity.

Polyesteranhydrides synthesized by the transesterification of ricinoleic acid and sebacic acid followed by anhydride polymerization were examined as potential controlled delivery carrier for paclitaxel. Solid and liquid polymers were used. Polymers containing 30% ricinoleic acid are solid whereas polymers containing 70% ricinoleic acid are liquid at body temperature and semisolid at room temperature. It was found that upon addition of the liquid polymer to water it solidifies to form a stable semisolid. Paclitaxel, a potent antitumor agent, was incorporated in the polymers (5-20% w/w) and its release in buffer solution was monitored. Paclitaxel was released for over 100 days while the polymer carrier was being degraded. The release rate was affected by the paclitaxel content; the higher the content, the slower was the release. The toxicity of the polymers and formulations with paclitaxel was examined by subcutaneous injection of liquid polymer samples or implantation of solid polymer specimens to mice for different time periods. Histopathological examination of the tissue surrounding the implant showed minor inflammation 1 week after the injection and no inflammation 3 weeks after implantation. Injection of the polymer without paclitaxel showed no adverse effects.

Animals↗
PubMed2001

Production of a novel compound, 7,10,12-trihydroxy-8(E)-octadecenoic acid from ricinoleic acid by Pseudomonas aeruginosa PR3.

The production and its potential use of a novel trihydroxy unsaturated fatty acid, 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD), were investigated. TOD was formed by Pseudomonas aeruginosa PR3 (NRRL B-18602) in a culture supplied with exogenous ricinoleic acid. The yield of TOD production was always higher in a rich culture medium than in minimal screening medium. Extending the conversion time from 48 to 72 h prior to lipid extraction led to a 65% reduction in yield, indicating that TOD was further metabolized by strain PR3 and that control of reaction time is important to achieving a maximum yield. The optimum culture density, reaction time, pH, temperature, and substrate concentration for the production of TOD were: 20-24 h culture growth, 48 h, 7.0, 25 degrees C, and 1% (vol/vol), respectively. Under optimum conditions, the yield of TOD production was greater than 45%. TOD was found to be an antifungal agent most active against the fungus that causes blast disease in rice plants, the most important fungal disease affecting rice production worldwide.

Culture Media↗
PubMed1965

THE BIOSYNTHESIS OF RICINOLEIC ACID.

1. Ricinoleic acid is shown to be synthesized in the immature castor bean seed only after 3-4 weeks from the time of fertilization. 2. Synthesis occurs both in the isolated embryo and the endosperm. 3. Linoleic acid does not act as precursor of ricinoleic acid in the isolated bean embryo. 4. Oleic acid is shown to be the direct precursor of ricinoleic acid. 5. The reaction does not use molecular oxygen. This suggests that ricinoleic acid is not a precursor of linoleic acid.

Acetates↗
PubMed1974

Effects of oleic and ricinoleic acids on net jejunal water and electrolyte movement. Perfusion studies in man.

To examine the effects of oleic acid and ricinoleic acid on jejunal absorption, steady-state jejunal perfusions were performed in healthy volunteers. Taurocholate, used to solubilize the fatty acids, did not influence absorption. Both fatty acids (concentration, 10 mM) reversed electrolyte and water net movement; that is, they induced fluid secretion; this effect was rapidly reversible. Ricinoleic acid (the active principle of castor oil) was the more potent, producing fluid secretion when perfused at concentrations at which oleic acid was without effect. However, ricinoleic acid was absorbed more slowly than was oleic acid, and hence was associated with higher intraluminal concentrations. Addition of lecithin and monoolein did not diminish the secretory effect of ricinoleic acid; addition of a secretory bile acid (taurodeoxycholate) did not enhance the effect. The response of the jejunal mucosa to a known cathartic provides observations pertinent to the pathophysiology of steatorrheal diseases in man. Dietary fatty acid also has secretory properties with respect to the human intestine; bacterial hydration, to hydroxy fatty acids, is not required to induce fluid secretion.

Body Water↗
PubMed2000

Metabolism of ricinoleic acid into gamma-decalactone: beta-oxidation and long chain acyl intermediates of ricinoleic acid in the genus Sporidiobolus sp.

In order to study differences in gamma-decalactone production in yeast, four species of Sporidiobolus were cultivated with 5% of methyl ricinoleate as the lactone substrate. In vivo studies showed different time courses of intermediates of ricinoleic acid breakdown between the four species. In vitro studies of the beta-oxidation system were conducted with crude cell extracts of Sporidiobolus spp. and with ricinoleyl-CoA (RCoA) as substrate. The beta-oxidation was detected by measuring acyl-CoA oxidase, 3-hydroxyacyl-CoA dehydrogenase activities, and acetyl-CoA production. The time courses of the CoA esters resulting from RCoA breakdown by crude extract of Sporidiobolus spp. permit the proposal of different metabolic models in the yeast. These models explained the differences observed during in vivo studies.

Acylation↗
PubMed1978

Stimulation of adenylate cyclase in homogenates of isolated intestinal epithelial cells from hamsters. Effects of gastrointestinal hormones, prostaglandins, and deoxycholic and ricinoleic acids.

The mechanism by which intestinal secretagogues evoke fluid secretion in the small bowel and colon has been suggested to involve mucosal adenylate cyclase. Adenylate cyclase activity was assayed by conversion of [32P]ATP to [32P]cyclic AMP in a system of pure epithelial cells isolated from the small intestine of the hamster by vibration in buffer. Several gastrointestinal hormones were tested for their capacity to stimulate adenylate cyclase; vasoactive intestinal peptide and impure cholecystokinin-pancreozymin (but not the 99% pure preparation or pure cholecystokinin octapeptide) were potent stimuli, but pentagastrin, glucagon, secretin, and gastric inhibitory peptide were impotent. Two prostaglandins, PGE1 and PGE2, were potent stimuli of adenylate cyclase. Two other compounds that provoke intestinal secretion of fluid, deoxycholic acid and ricinoleic acid (castor oil), were ineffective stimuli of adenylate cyclase. These experiments do not support a clear-cut relationship between a compound's ability to stimulate adenylate cylase and its activity as an intestinal secretagogue.

Adenylyl Cyclases↗
PubMedDate not supplied

Macrolactones and polyesters from ricinoleic acid.

A systematic study on the synthesis, characterization, and polymerization of ricinoleic acid (RA) lactone is reported. Ricinoleic acid lactones were synthesized by refluxing pure ricinoleic acid in chloroform (10 mg/mL) with dicyclohexylcarbodimide and (dimethylamino)pyridine as catalyst. Purification of RA lactones was performed by silica gel chromatography. The reaction resulted in a 75% yield of ricinoleic acid lactones. IR and NMR analysis confirmed the formation of cyclic compounds. Polymerization of the ricinoleic acid lactones with catalysts commonly used for ring-opening polymerization of lactones, under specific reaction conditions, resulted in oligomers. Copolymerization with lactide (LA) by ring-opening polymerization, using Sn(Oct) as catalyst, yielded copolyesters with molecular weights (M(w)) in the range of 5000-16000 and melting temperatures of 100-130 degrees C for copolymers containing 10-50% w/w ricinoleic acid residues. Degradation studies of the copolymers were performed in 0.1 M phosphate buffer solution, pH 7.4, at 37 degrees C. P(LA-RA)s with up to 20% w/w RA slowly degraded and released only approximately 7% of its lactic acid content after 60 days of study, while pure PLA under similar conditions released more than 20% of its lactic acid content. On the other hand, copolyesters containing more then 20% w/w RA degraded and released lactic acid faster than pure PLA due to the low crystallinity of the copolymers.

Lactones↗
PubMed2002

Ricinoleic acid and castor oil as substrates for conjugated linoleic acid production by washed cells of Lactobacillus plantarum.

Ricinoleic acid (12-hydroxy-cis-9-octadecaenoic acid) was an effective substrate for conjugated linoleic acid (CLA) production by washed cells of Lactobacillus plantarum AKU 1009a. The CLA produced was a mixture of cis-9,trans-11- and trans-9,trans-11-octadecadienoic acids. Addition of alpha-linolenic acid to the culture medium increased the CLA productivity of the washed cells. In the presence of lipase, castor oil, in which the main fatty acid component is ricinoleic acid, also was a substrate for CLA.

Castor Oil↗
PubMed2002

Production of conjugated linoleic acids through KOH-catalyzed dehydration of ricinoleic acid.

Production of conjugated linoleic acids (CLA) using castor oil as starting material involves conversion of ricinoleic acid to methyl 12-mesyloxy-octadec-9-enoate (MMOE) followed by dehydration. This process usually uses 1,8-diazabicyclo-(5.4.0)-undec-7-ene (DBU) as an expensive dehydrating reagent. The present study reports that potassium hydroxide (KOH) can serve as a dehydrating reagent in replacement of DBU. The results showed that conversion of MMOE to CLA catalyzed by KOH was an efficient reaction, with a 77% conversion efficiency at 80 degrees C. The CLA isomeric profile produced in KOH-catalyzed dehydration reaction was similar to that catalyzed by DBU. The CLA mixture produced in KOH-catalyzed dehydration of MMOE at 80 degrees C contained 72% 9c,11t-18:2 and 26% 9c,11c-18:2 while in that catalyzed by DBU, 9c,11t-18:2 and 9c,11c-18:2 accounted for 78 and 16%, respectively. It was found that the temperature of dehydration was an important factor in the determination of CLA isomer composition and yield of conversion. Elevating the temperature from 78 to 180 degrees C decreased not only the conversion efficiency but also production of total c,t-18:2 and c,c-18:2 isomers regardless of dehydration catalyzed by either DBU or KOH. It is concluded that KOH may replace DBU as a dehydrating reagent in conversion of MMOE to CLA when the reaction conditions are optimized.

Castor Oil↗
PubMed1986

Translocation of indigenous bacteria from the gastrointestinal tract of mice after oral ricinoleic acid treatment.

A single dose of ricinoleic acid, the active component of castor oil, administered intragastrically to specific pathogen-free mice produced significant alterations in the proximal small intestinal mucosa. Two hours after drug administration, the duodenal villi were markedly shortened with massive exfoliation of columnar and goblet cells. This disruption of the mucosal barrier resulted in continuity between the intestinal lumen and the lamina propria of the villi. Because of the loss of the mucosal barrier, bacteria of the indigenous gastrointestinal flora translocated from the gastrointestinal lumen to the mesenteric lymph nodes, spleen, and liver. The peak incidence of bacterial translocation occurred 4 days after the ricinoleic acid treatment. Strictly anaerobic bacteria, which normally colonize the gastrointestinal tract at greater levels than aerobic or facultatively anaerobic bacteria, were translocated at a greater incidence to the mesenteric lymph nodes than were the other indigenous bacteria. The mucosa began regenerating within 4 h after the ricinoleic acid treatment and viable translocated bacteria were no longer cultured from the mesenteric lymph nodes by 7 days after treatment.

Animals↗
PubMed2000

Antinociceptive activity of ricinoleic acid, a capsaicin-like compound devoid of pungent properties.

The antinociceptive effect of ricinoleic acid ([R-(Z)]-12-hydroxy-9-octadecenoic acid) in comparison with capsaicin (trans-8-methyl-N-vanillyl-6-nonenamide) has been investigated in several "in vivo" tests. Acute topical application of capsaicin, but not ricinoleic acid, produced by itself an hyperalgesic effect detected as a decrease in paw withdrawal latency in response to a painful (heat) stimulus in mice. Capsaicin, but not ricinoleic acid at any dose tested, showed an irritant effect in the wiping test in guinea pig conjunctiva after local application and in the paw licking test in mice after intradermal injection. Whereas acute application of ricinoleic acid or capsaicin decreased paw withdrawal latency to heat in the presence of a pre-existing inflammation (injection of carrageenan in the mouse paw), the repeated local treatment for 8 days with either compounds markedly increased paw withdrawal latency. In a chronic model of inflammation (complete Freund's adjuvant arthritis in mice), the repeated topical and intradermal treatments with both ricinoleic acid and capsaicin increased paw withdrawal latency to heat, the antinociceptive effect of ricinoleic acid being more persistent than that of capsaicin. Antinociceptive effect of 8 days of treatment with ricinoleic acid and capsaicin was observed in acetic acid-induced writhing in mice, capsaicin-induced foot licking in mice and capsaicin-induced wiping movements in guinea pig conjunctiva. A decrease of substance P tissue levels in the mouse paw was found after repeated treatment with ricinoleic acid. In conclusion, ricinoleic acid seems to be a new antinociceptive agent lacking the pungent and acute hyperalgesic properties of capsaicin.

Administration, Topical↗
PubMed1992

PAF formation by human gastrointestinal mucosa/submucosa in-vitro: release by ricinoleic acid, and inhibition by 5-aminosalicylic acid.

Human isolated gastrointestinal mucosa/submucosa incubated with ricinoleic acid (12.5-100 micrograms mL-1) or the calcium ionophore A23187 (10 micrograms mL-1) released platelet-activating factor (PAF) as determined by a scintillation proximity assay after extraction and purification. 5-Aminosalicylic acid (25-100 micrograms mL-1) inhibited PAF release by ricinoleic acid in a concentration-dependent manner, and 50 micrograms mL-1 reduced the effect of A23187. We suggest that PAF may play a role in the laxation and mucosal damage by ricinoleic acid released from castor oil.

Aminosalicylic Acids↗