Melanogenesis-inhibitory saccharide fatty acid esters and other constituents of the fruits of Morinda citrifolia (noni)

Five new saccharide fatty acid esters, named nonioside P (3), nonioside Q (4), nonioside R (8), nonioside S (10), and nonioside T (14), and one new succinic acid ester, butyl 2-hydroxysuccinate (=4-butoxy-3-hydroxy-4-oxobutanoic acid) (31), were isolated, along with 26?known compounds, including eight saccharide fatty acid esters, 1, 2, 5, 6, 7, 9, 12, and 13, three hemiterpene glycosides, 15, 17, and 18, six iridoid glycosides, 21-25, and 27, and nine other compounds, 20, 28, 29, and 32-37, from a MeOH extract of the fruit of Morinda citrifolia (noni). Upon evaluation of these and five other glycosidic compounds, 11, 16, 19, 26, and 30, from M. citrifolia fruit extract for their inhibitory activities against melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), most of the saccharide fatty acid esters, hemiterpene glycosides, and iridoid glycosides showed inhibitory effects with no or almost no toxicity to the cells. These compounds were further evaluated with respect to their cytotoxic activities against two human cancer cell lines (HL-60 and AZ521) and their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells.     

Antileukemic effects of Didemnum psammatodes (Tunicata: Ascidiacea) constituents

Chemical investigation of the methanolic extract of the ascidian Didemnum psammatodes has led to the identification of fourteen known compounds: three methyl esters (methyl myristate, methyl palmitate and methyl stearate), four steroids (cholesterol, campesterol, stigmasterol and beta-sitosterol), two fatty acids (palmitic acid and stearic acid), three glyceryl ethers {(1,2-propanediol, 3-(heptadecyloxy), batyl alcohol and 1,2-propanediol, 3-[(methyloctadecyl)oxy]} and two nucleosides (thymidine and 2'-deoxyguanosine). Their structures were proposed by NMR and comparison with literature data and GC analysis in comparison with authentic sample. The cytotoxic activity of these compounds was evaluated against human leukemia cell line panel using the MTT assay. The mixture of the three methyl esters was the most active group of compounds, showing antiproliferative and cytotoxic effects. Further studies on their mode of action suggest that these activities are connected with inhibition of DNA synthesis and induction of both necrosis and apoptosis.     

具有细胞毒活性红树林真菌094811的鉴定

为鉴定合成细胞毒活性及多羟基甾醇脂肪酸酯新结构代谢产物的红树林真菌094811,采用形态观察、BIOLOG生理特征鉴定及核糖体18S rDNA测序对菌株094811进行了鉴定。菌株094811与模式菌株黑曲霉As3.40、泡盛曲霉As3.44形态特征极为相似,难以区分。扫描电镜下分别观察且比较菌株094811、模式菌株黑曲霉As3.40、泡盛曲霉As3.44分生孢子的形态,判断菌株094811为泡盛曲霉;根据BIOLOG微生物鉴定系统给出的相似菌种名称及综合形态和生理生化特征,推断菌株094811为泡盛曲霉;通过18S rDNA部分序列测序、GenBank比对,及系统演化分析进一步确认菌株094811为泡盛曲霉。菌株094811的形态、生理特征及其核糖体18S rDNA的序列特征给出了一致的结论。首次鉴定发现1株具有合成细胞毒活性及新的多羟基甾醇脂肪酸酯结构化合物的能力的泡盛曲霉。     

Melanogenesis‐Inhibitory Saccharide Fatty Acid Esters and Other Constituents of the Fruits of Morinda citrifolia (Noni)

Five new saccharide fatty acid esters, named nonioside P ( 3 ), nonioside Q ( 4 ), nonioside R ( 8 ), nonioside S ( 10 ), and nonioside T ( 14 ), and one new succinic acid ester, butyl 2‐hydroxysuccinate (=4‐butoxy‐3‐hydroxy‐4‐oxobutanoic acid) ( 31 ), were isolated, along with 26 known compounds, including eight saccharide fatty acid esters, 1, 2, 5, 6, 7, 9, 12 , and 13 , three hemiterpene glycosides, 15, 17 , and 18 , six iridoid glycosides, 21 – 25 , and 27 , and nine other compounds, 20, 28, 29 , and 32 – 37 , from a MeOH extract of the fruit of Morinda citrifolia (noni). Upon evaluation of these and five other glycosidic compounds, 11, 16, 19, 26 , and 30 , from M. citrifolia fruit extract for their inhibitory activities against melanogenesis in B16 melanoma cells induced with α‐melanocyte‐stimulating hormone (α‐MSH), most of the saccharide fatty acid esters, hemiterpene glycosides, and iridoid glycosides showed inhibitory effects with no or almost no toxicity to the cells. These compounds were further evaluated with respect to their cytotoxic activities against two human cancer cell lines (HL‐60 and AZ521) and their inhibitory effects on Epstein? Barr virus early antigen (EBV‐EA) activation induced with 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) in Raji cells.     

Fatty acid alcohol ester-synthesizing activity of lipoprotein lipase

The fatty acid alcohol ester-synthesizing activity of lipoprotein lipase (LPL) was characterized using bovine milk LPL. Synthesizing activities were determined in an aqueous medium using oleic acid or trioleylglycerol as the acyl donor and equimolar amounts of long-chain alcohols as the acyl acceptor. When oleic acid and hexadecanol emulsified with gum arabic were incubated with LPL, palmityl oleate was synthesized, in a time- and dose-dependent manner. Apo-very low density lipoprotein (apoVLDL) stimulated LPL-catalyzed palmityl oleate synthesis. The apparent equilibrium ratio of fatty acid alcohol ester/oleic acid was estimated using a high concentration of LPL and a long (20 h) incubation period. The equilibrium ratio was affected by the incubation pH and the alcohol chain length. When the incubation pH was below pH 7.0 and long chain fatty acyl alcohols were used as substrates, the fatty acid alcohol ester/free fatty acid equilibrium ratio favored ester formation, with an apparent equilibrium ratio of fatty acid alcohol ester/fatty acid of about 0.9/0.1. The equilibrium ratio decreased sharply at alkaline pH (above pH 8.0). The ratio also decreased when fatty alcohols with acyl chains shorter than dodecanol were used. When a trioleoylglycerol/fatty acyl alcohol emulsion was incubated with LPL, fatty acid alcohol esters were synthesized in a dose- and time-dependent fashion. Fatty acid alcohol esters were easily synthesized from trioleoylglycerol when fatty alcohols with acyl chains longer than dodecanol were used, but synthesis was decreased with fatty alcohols with acyl chain lengths shorter than decanol, and little synthesizing activity was detected with shorter-chain fatty alcohols such as butanol or ethanol.     

Modification of fatty acid selectivity of <Emphasis Type="Italic">Candida antarctica</Emphasis> lipase A by error-prone PCR

Objective

To generate Candida antarctica lipase A (CAL-A) mutants with modified fatty acid selectivities and improved lipolytic activities using error-prone PCR (epPCR).

Results

A Candida antarctica lipase A mutant was obtained in three rounds of epPCR. This mutant showed a 14 times higher ability to hydrolyze triacylglycerols containing conjugated linoleic acids, and was 12 and 14 times more selective towards cis-9, trans-11 and trans-10, cis-12 isomers respectively, compared to native lipase. Lipolytic activities towards fatty acid esters were markedly improved, in particular towards butyric, lauric, stearic and palmitic esters.

Conclusion

Directed molecular evolution is an efficient method to generate lipases with desirable selectivity towards CLA isomers and improved lipolytic activities towards esters of fatty acids.

     

Feeding stimulants eliciting the probing behavior for Peregrinator blannulipes Montrouzier et Signore (Hemiptera: Ruduviidae) from Tribolium confusum (Jacquelin du Val)

Four fatty acid methyl esters identified in the solvent extract of Tribolium confusum (Jacquelin du Val) larvae as kairomones were individually and collectively tested for probing behavior of Peregrinator biannulipes Montrouzier et Signoret. All identified fatty acid methyl eaters, methyl palmitate, methyl linolate, methyl oleate and methyl stearate, exhibited characterisitic kairomonal probing behavior of P. biannulipe toward the lure. These fatty acid methyl ester were active at 0.2 microg/lure but a synergistic effect was not observed among them. Commercially available C8-C14 even-numbered fatty acid methyl esters that were not detected in the extract of T. confusum larvae also elicited a probing behavior but their activities were weaker than those of four fatty acid methyl ester (C16:0, C18:0, C18:1 and C18:2) identified in the extract. On the other hand, C17 and C19 odd-numbered fatty acid methyl esters did not show any activity at all.     

Cuticular waxes from potato (Solanum tuberosum) leaves

The qualitative and quantitative compositions of leaf cuticular waxes from potato (Solanum tuberosum) varieties were studied. The principal components of the waxes were very long chain n-alkanes, 2-methylalkanes and 3-methylalkanes (3.1-4.6 microg cm(-2)), primary alcohols (0.3-0.7 microg cm(-2)), fatty acids (0.3-0.6 microg cm(-2)), and wax esters (0.1-0.4 microg cm(-2)). Methyl ketones, sterols, beta-amyrin, benzoic acid esters and fatty acid methyl, ethyl, isopropyl and phenylethyl esters were found for the first time in potato waxes. The qualitative composition of the waxes was quite similar but there were quantitative differences between the varieties studied. A new group of cuticular wax constituents consisting of free 2-alkanols with odd and even numbers of carbon atoms ranging from C25 to C30 was identified.     

Quantitative analysis of fatty acid precursors in marine samples: direct conversion of wax ester alcohols and dimethylacetals to FAMEs

To apply fatty acid analyses to the study of foraging ecology and diet determination, all compounds that may be deposited as fatty acids in a predator must be quantified in the prey. These compounds include the usual fatty acids in acyl lipids, but also the alcohols of wax esters and the vinyl ethers of plasmalogens. In routine fatty acid analysis, samples are extracted and transesterified (methylated), resulting in the formation of fatty acid methyl esters (FAMEs); however, fatty alcohols and dimethylacetals (DMAs) are also generated if wax esters or plasmalogens are present. Here, we present a new method using a modified Jones' reagent to oxidize these alcohols and DMAs to free fatty acids (FFAs). These FFAs are then easily methylated and quantitatively recombined with FAMEs from the same sample. This generates a fatty acid signature of prey that is equivalent to that which the predator has available for deposition upon digestion of that prey. This method is validated with alcohol and DMA standards. Its application to typical marine samples is also presented, demonstrating the change in effective fatty acid signature after inclusion of fatty acids derived from wax esters and plasmalogens.     

One-pot synthesis of polyunsaturated fatty acid amides with anti-proliferative properties

A one-pot environmentally friendly transamidation of ω-3 fatty acid ethyl esters to amides and mono- or diacylglycerols was investigated via the use of a polymer-supported lipase. The method was used to synthesize a library of fatty acid monoglyceryl esters and amides. These new derivatives were found to have potent growth inhibition effects against A549 lung cancer cells.     

An investigation of the use of recovered vegetable oil for the preparation of starch thermoplastics

The main components (90%) in recovered vegetable oil (RVO) are esters of higher carboxylic acids and glycerol (triglycerides) which consist of three fatty acids: oleic (C18:1, Z), palmitic (C16:0) and linoleic (C18:2, Z) in the ratio 2.8:1.4:1. RVO may provide a low cost new supply of unsaturated fatty acid chlorides. Modification of potato starch using the mixture of fatty acid chlorides derived from RVO and using acid chlorides of the two major pure component acids has been performed. Films were prepared from the starch esters and mechanical properties tested. Commercially available potato starch, modified to DS-value 1.5 with RVO-derived acyl chlorides, was thermoplastic with a maximum tensile strength of 1.4 MPa and an elongation at break of 54%.     

A comparison of the fatty acid esters of estradiol and corticosterone synthesized by tissues of the rat

The biosynthesis of the fatty acid esters of the corticoid (corticosterone) and estrogen (estradiol) was compared in parallel incubations of corticosterone and estradiol with several tissues of the rat. The fatty acid composition of the esters of the two steroids was characterized in mammary and uterine tissue. In both of these tissues, the esters of estradiol were extremely heterogeneous. To the contrary, in the same tissues only one predominant ester of corticosterone, corticosterone-21-oleate, was formed. It comprised 70-80% of the total. The oleate ester of estradiol accounted for only 20% of the esters of this estrogen. In addition, fatty acid esters of an A-ring reduced metabolite of corticosterone, 5 beta-dihydrocorticosterone, was also identified. Its fatty acid composition is identical to that of corticosterone. In other experiments the fatty acid esters of both steroids were isolated from several tissues and quantified. When the amount of steroidal ester formed was compared, there was over a 100-fold difference among the various tissues in the ratio of estradiol to corticosterone ester synthesized. Thus, the rate of synthesis of the fatty acid esters of each class of steroid varies dramatically from tissue to tissue, and their fatty acid composition differs markedly as well. If the same enzyme synthesized both the estrogen and corticoid esters, then it would be expected that the relative amount of both esters synthesized in various tissues should be constant and likewise that their composition should be the same. Since neither occurred, these results suggest that the enzyme which produces the C-17 fatty acid esters of the estrogens may be different from the one which synthesizes the C-21 esters of the corticoids. The existence of separate enzyme systems for the synthesis of the fatty acid esters of these steroid hormones opens the possibility of specific physiological controls of each of these unusual steroidal metabolites.     

Fatty acid metabolism in liver of rats treated with hypolipidemic sulphur-substituted fatty acid analogues

The purpose of this study was to investigate early biochemical changes and possible mechanisms via which alkyl(C12)thioacetic acid (CMTTD, blocked for beta-oxidation), alkyl(C12)thiopropionic acid (CETTD, undergo one cycle of beta-oxidation) and a 3-thiadicarboxylic acid (BCMTD, blocked for both omega- (and beta-oxidation) influence the peroxisomal beta-oxidation in liver of rats. Treatment of rats with CMTTD caused a stimulation of the palmitoyl-CoA synthetase activity accompanied with increased concentration of hepatic acid-insoluble CoA. This effect was already established during 12-24 h of feeding. From 2 days of feeding, the cellular level of acid-insoluble CoA began to decrease, whereas free CoASH content increased. Stimulation of [1-14C]palmitoyl-CoA oxidation in the presence of KCN, palmitoyl-CoA-dependent dehydrogenase (termed peroxisomal beta-oxidation) and palmitoyl-CoA hydrolase activities were revealed after 36-48 h of CMTTD-feeding. Administration of BCMTD affected the enzymatic activities and altered the distribution of CoA between acid-insoluble and free forms comparable to what was observed in CMTTD-treated rats. It is evident that treatment of peroxisome proliferators (BCMTD and CMTTD), the level of acyl-CoA esters and the enzyme activity involved in their formation precede the increase in peroxisomal and palmitoyl-CoA hydrolase activities. In CMTTD-fed animals the activity of cyanide-insensitive fatty acid oxidation remained unchanged when the mitochondrial beta-oxidation and carnitine palmitoyltransferase operated at maximum rates. The sequence and redistribution of CoA and enzyme changes were interpreted as support for the hypothesis that substrate supply is an important factor in the regulation of peroxisomal fatty acid metabolism, i.e., the fatty acyl-CoA species appear to be catabolized by peroxisomes at high rates only when uptake into mitochondria is saturated. Administration of CETTD led to an inhibition of mitochondrial fatty acid oxidation accompanied with a rise in the concentration of acyl-CoA esters in the liver. Consequently, fatty liver developed. The peroxisomal beta-oxidation was marginally affected. Whether inhibition of mitochondrial beta-oxidation may be involved in regulation of peroxisomal fatty acid metabolism and in development of fatty liver should be considered.     

Esterification of vertebrate-type steroids in the Eastern oyster (Crassostrea virginica)

Characteristics of acyl-coenzyme A (acyl-CoA):steroid acyltransferase from the digestive gland of the oyster Crassostrea virginica were determined by using estradiol (E2) and dehydroepiandrosterone (DHEA) as substrates. The apparent Km and Vmax values for esterification of E2 with the six fatty acid acyl-CoAs tested (C20:4, C18:2, C18:1, C16:1, C18:0, and C16:0) were in the range of 9-17 microM E2 and 35-74 pmol/min/mg protein, respectively. Kinetic parameters for esterification of DHEA (Km: 45-120 microM; Vmax: 30-182 pmol/min/mg protein) showed a lower affinity of the enzyme for this steroid. Formation of endogenous fatty acid esters of steroids by microsomes of digestive gland and gonads incubated in the presence of ATP and CoA was assessed, and at least seven E2 fatty acid esters and five DHEA fatty acid esters were observed. Some peaks eluted at the same retention times as palmitoleoyl-, linoleoyl-, oleoyl/palmitoyl-, and stearoyl-E2; and palmitoleoyl-, oleoyl/palmitoyl-, and stearoyl-DHEA. The same endogenous esters, although in different proportions, were produced by gonadal microsomes. The kinetic parameters for both E2 (Km: 10 microM; Vmax: 38 pmol/min/mg protein) and DHEA (Km: 61 microM; Vmax: 60 pmol/min/mg protein) were similar to those obtained in the digestive gland. Kinetic parameters obtained are similar to those observed in mammals; thus, fatty acid esterification of sex steroids appears to be a well-conserved conjugation pathway during evolution.     

Enzymatic synthesis and anti-oxidative activities of plant oil-based ascorbyl esters in 2-methyltetrahydrofuran-containing mixtures

Ascorbyl fatty acid esters are commercially interesting fat-soluble antioxidants. In this work, enzymatic synthesis of ascorbyl esters from less expensive and readily available plant oils, and their anti-oxidative activities are described. Among the immobilized lipases tested, Candida antarctica lipase B was the best for the synthesis of plant oil-based ascorbyl esters. The enzyme showed much better catalytic performances in the binary mixtures of biomass-based 2-methyltetrahydrofuran (MeTHF) and t-butanol than the previously preferred t-butanol. The conversions of 70–73% were obtained under the optimal reaction conditions after 24?h, with the unsaturated fatty acid esters (oleate and linoleate, 80–90%) as the major products. The immobilized lipase kept the relative activity of 80% after reuse for 6 batches in MeTHF-containing system. Besides, anti-oxidative activities of plant oil-based ascorbyl esters and ascorbic acid were comparable, which could remove α,α-diphenyl-β-picrylhydrazyl (DPPH) free radical of >87%.     

播娘蒿种子脂肪油组分的GC-MS分析

播娘蒿[Descurainia sophia（L．）Webb ex Prantl]为十字花科（Cruciferae）播娘蒿属（Descuainia Webb et Berth）1～2年生草本植物,其成熟的种子俗称南葶苈子,为临床常用中药材。葶苈子味辛、苦、大寒,具泻肺降气、祛痰平喘、行水消肿之功效。用于痰涎壅肺、喘咳痰多、胸肋胀满、胸腹水肿、小便不利、肺原性心脏病水肿等症。     

Turnover of cholesteryl esters of plasma lipoproteins in the rat

Turnover of individual classes of cholesteryl esters (classified on the basis of the degree of unsaturation of the fatty acid moiety) in rat plasma lipoproteins and liver was studied after the administration of mevalonic acid-5-(3)H and mevalonic acid-2-(14)C. The relative turnover rate was greatest in the d < 1.019 lipoproteins, with monoenes > saturated = dienes > tetraenes. In the d > 1.063 lipoproteins, all cholesteryl esters had slower turnover rates, but tetraenes = pentaenes > dienes > monoenes = saturated. Comparisons of specific activities of individual cholesteryl ester classes of liver subcellular fractions and lipoproteins suggest that the d < 1.019 lipoprotein cholesteryl esters are synthesized from newly synthesized cholesterol in the liver and are rapidly released into this lipoprotein. Tetraenoic cholesteryl esters, however, may originate from esterification of free cholesterol in plasma. Tetraenoic esters are formed from cholesterol in plasma during incubation or ultracentrifugation unless a thiol-reacting or alkylating agent is added. Failure to add such a reagent to plasma results in erroneous specific activities. In the adrenal, relative rates of synthesis of cholesteryl esters are monoenes = dienes > tetraenes > trienes = pentaenes > saturated. It is concluded that cholesteryl ester turnover in the rat, as opposed to man, is determined not only by the particular lipoprotein class but also by the fatty acid moiety of the ester.     

Isolation and characterization of fatty acid methyl ester (FAME)‐producing Streptomyces sp. S161 from sheep (Ovis aries) faeces

An actinomycete producing oil‐like mixtures was isolated and characterized. The strain was isolated from sheep faeces and identified as Streptomyces sp. S161 based on 16S rRNA gene sequence analysis. The strain showed cellulase and xylanase activities. The ¹H nuclear magnetic resonance (NMR) spectra of the mixtures showed that the mixtures were composed of fatty acid methyl esters (52·5), triglycerides (13·7) and monoglycerides (9·1) (mol.%). Based on the gas chromatography–mass spectrometry (GC‐MS) analysis, the fatty acid methyl esters were mainly composed of C14‐C16 long‐chain fatty acids. The results indicated that Streptomyces sp. S161 could produce fatty acid methyl esters (FAME) directly from starch. To our knowledge, this is the first isolated strain that can produce biodiesel (FAME) directly from starch.

Significance and Impact of the Study

Nowadays, production of biodiesel is based on plant oils, animal fats, algal oils and microbial oils. Lipid mostly consists of triacylglycerols (TAG), and conversion of these lipids into fatty acid short‐chain alcohol esters (methanol or ethanol) is the final step in biodiesel production. In this study, an oil‐producing Streptomyces strain was isolated from sheep faeces. The oil was composed of C₁₄‐C₁₆ long‐chain fatty acid methyl esters, triglycerides and monoglycerides. This is the first isolated strain‐producing biodiesel (FAME) directly from starch. Due to showing cellulase and xylanase activities, the strain would be helpful for converting renewable lignocellulose into biodiesel directly.     

Metabolism of chylomicrons by the isolated rat liver

Isolated livers perfused with washed corn oil chylomicrons labeled in vivo with palmitic acid-1-(14)C removed a large proportion of the chylomicrons. Slices from these livers oxidized chylomicron fatty acid esters to both carbon dioxide and acetoacetate. The liver slices also generated free fatty acids from chylomicron lipids and converted chylomicron triglycerides to phospholipids. Similar activities were observed in rat liver slices prepared shortly after the intravenous administration of chylomicrons to intact rats. The observed chylomicron uptake and lipid conversions were similar in livers from both fed and fasted rats. Fasting increased the oxidation of chylomicron fatty acid esters by livers labeled in vivo and by perfusion. In livers removed from intact rats given labeled chylomicrons, the triglyceride-(14)C to phospholipid-(14)C ratio was high, a finding unexpected if the liver had acquired this (14)C by removal of circulating fatty acids formed by extrahepatic lipolysis. These results demonstrate the ability of the liver to remove and utilize chylomicrons directly and suggest that direct removal accounts for a significant portion of the chylomicron fatty acids utilized by the liver of intact rats.