Insoluble Acid Research Articles

Nutrient allocation in the gonads of the sea urchin Arbacia dufresnii in different stages of gonadal development

This study reports nutrient allocation in different stages of gonadal development for two populations of the sea urchin Arbacia dufresnii off the Patagonian coast of Argentina (Nuevo Gulf and San Jorge Gulf). The biochemical composition of gonads was used to assess nutrient allocation by measuring ash, soluble protein, lipid and trichloroacetic acid-soluble carbohydrate concentrations, and absolute contents over a 24-month period. Reproductive output in terms of energy was calculated for females. Results were correlated with histological stage of the gonads. Soluble proteins were the main component for the Nuevo Gulf population while unmeasured organic material (i.e. insoluble proteins and nucleic acids, especially in testes) was prevalent in gonads from San Jorge Gulf. Soluble protein and lipid concentrations followed the gonadal cycle, while carbohydrate concentration was almost negligible, especially in the Nuevo Gulf population. The different patterns in the gonadal cycle in the two populations were reflected in the biochemical composition of gonads. Concentrations and contents of the biochemical components and reproductive output were higher in the population from San Jorge Gulf owing to the larger size of gonads and gametes. These findings contribute to the better understanding of the plasticity of the reproductive biology of A. dufresnii in different environments.

Dendeng Ikan Leubiem (Canthidermis maculatus) dengan Variasi Metode Pembuatan, Jenis Gula, dan Metode Pengeringan

Leubiem fish (Canthidermis maculatus) is one of marine species in Aceh. As a perishable food product, this fish is needed to be processed becoming jerky products to prevent the damage. Jerky is a semi-moist food which is usually made from meat or fish, slab, wide and dried with additional of sugar, salt, spices and others. This study aims to determine the effect of jerk’s making methods (sliced and milled), types of sugars (white sugar and brown sugar), and drying methods (cabinet and sun drying) on the quality of the fish jerky. This study was conducted using a randomized block design (RBD) factorial with three replications. Analysis of the products includes of yields, moisture content, protein content, insoluble acid ash content, and organoleptic test. The results showed that the milled jerky had a higher yield and higher organoleptic texture score than sliced jerky. However, sliced jerky had a lower moisture content and higher protein content than milled jerky. The best quality of leubiem fish jerky was obtained in milled jerky, using white sugar, and sun drying method with the characteristics: yield 51.81%, moisture content 8.20%, protein content 53.94%, insoluble acid ash content 0.36%, and organoleptic tests scores: color 3.28 (neutral), flavor 3.35 (neutral), taste 3.33 (neutral), and texture 3.15 (neutral).

Effect of physical effectiveness on digestibility of ration for cows in early lactation

A study was conducted to investigate the effects of a diet particle size on nutrient digestibility in cows in early lactation. Treatments were diets with forage to concentrate ratio 43:57% in diet dry matter, with four different physically effective fibres (peNDF) content based on different cut length of corn silage and alfalfa haylage. The physical effectiveness factors (pef) and peNDF content of TMRs (total mixed ration) were determined using Penn State Particle Separator (PSPS) with two (pef8.0 , peNDF8.0) or three (pef1.18, peNDF1.18) sieves. The reducing of cut length of forages and particle size of diets did not affect on dry matter intake, while decreased peNDF intake by 16.34 and 8.83%, for peNDF8.0 and peNDF1.18 respectively. Apparent total tract digestibility of the nutrients was measured using two indicators: acid insoluble ash (AIA) and acid detergent insoluble lignin (ADL). Decreasing of forages cut length significantly increased apparent total tract digestibility of neutral detergent fibre (NDF) from 48.39% to 53.84% and from 53.9% to 58.66%, of crude protein from 73.96% to 79.24% and from 71.56% to 77.90%, with contemporary decreasing of non-fibre carbohydrate from 90.89% to 84.81% and from 91.99% to 86.80%, with AIA or ADL as indicator respectively. Dietary value of net energy for lactation (NEL) and energy intake was not affected by the peNDF content of the diet.

Dynamic characteristics of sugar accumulation and related enzyme activities in sweet and non-sweet watermelon fruits

Sugar content largely determines watermelon fruit quality. We compared changes in sugar accumulation and activities of carbohydrate enzymes in the flesh (central portion) and mesocarp of elite sweet watermelon line 97103 (Citrullus lanatus subsp. vulgaris) and exotic non-sweet line PI296341-FR (C. lanatus subsp. lanatus) to elucidate the physiological and biochemical mechanisms of sugar accumulation in watermelon fruit. The major translocated sugars, raffinose and stachyose, were more unloaded into sweet watermelon fruit than non-sweet fruit. During the fruit development, acid α-galactosidase activity was much higher in flesh of 97103 than in mesocarp of 97103, in flesh and mesocarp of PI296341-FR fruit. Insoluble acid invertase activity was higher in 97103 flesh than in 97103 mesocarp, PI296341-FR flesh or mesocarp from 18 days after pollination (DAP) to 34 DAP. Changes in soluble acid invertase activity in 97103 flesh were similar to those in PI296341-FR flesh and mesocarp from 18 DAP to full ripening. Sucrose synthase and sucrose phosphate synthase activities in 97103 flesh were significantly higher than those in 97103 mesocarp and PI296341-FR fruits from 18 to 34 DAP. Only insoluble acid invertase and sucrose phosphate synthase activities were significantly positively correlated with sucrose content in 97103 flesh. Therefore, phloem loading, distribution and metabolism of major translocated sugars, which are controlled by key sugar metabolism enzymes, determine fruit sugar accumulation in sweet and non-sweet watermelon and reflect the distribution diversity of translocated sugars between subspecies.

Standardization and Preliminary Anti-Angiogenic Study of Labisia Pumila

Labisia pumila var. alata (Myrinaceae) locally known as Kacip Fatimah is widely used as traditional medicine in Malaysia. Standardization of herbal preparations is vital to maintain quality, efficacy and safety. This study aims to obtain the phytochemical profile of L. pumila and to study the anti-angiogenic effect of the ethanolic, 50% ethanolic and water extracts of the whole plant. The standardization was done according to the WHO guidelines. Three testing parameters tested including identity (microscopic and TLC profiling), purity (foreign matter, total ash, insoluble acid ash, moisture content and content of extractable matter) and chromatographic and spectroscopic analysis (HPLC, UV-Vis and FT-IR profiling). The rat aortic ring assay was performed to investigate the anti-angiogenic effect of the extracts. Identity of the plant was confirmed by comparing the results with the Malaysian Herbal Monograph Vol.1 (MHM). The purity test results showed studied parameters fall within the normal range of the MHM. HPLC chromatography showed the presence of gallic acid at the retention time of 6.9 min. The maxima absorbance of UV-Vis was at 270nm and the main FT-IR bands vibration were obtained at 3335, 1604 and 1042 cm. The anti-angiogenic test showed 100% inhibition of microvessels outgrowth in the ethanolic and 50% ethanolic extracts at 100 μg/ml whereas the water extract showed 32% inhibition. The rat aortic rings test showed a possible anti-angiogenic effect which may have interesting applications in the treatment of angiogenesis related disorders.

PEMERIKSAAN FARMAKOGNOSTIK DAN PROFIL KROMATOGRAFI LAPIS TIPIS TUMBUHAN SARANG SEMUT (Myrmeco diapendans Merr. & Perry) ASAL KABUPATEN TELUK BINTUNI PAPUA BARAT

Pharmacognostic assay and Profile of Thin Layer Chromatography Myrmecodia Plant (Myrmecodia pendens Merr & Perry) from Bintuni Bay, west Papua. Morphologycal Identification showed that Myrmecodia Plant (Myrmecodia pendens Merr & Perry) include magnoliopsida class with steep root system. Leaf anantomy from the leaf showed that anomositic type stomata.Powder extracbility of Myrmecodia Plant (Myrmecodia pendens Merr & Perry) including total ash is 33,92% and insoluble acid ash is 7,78%. While in the water soluble extractive 15,09% and aethanol soluble extractive 5,40%. Chemical identification on the tuberous powder showed that it is consist of tannin (pirogalotanin) and flavanoid. Profile of Thin layer chromatography obtained total spot more diethyl ether extract equel to 8 spot and n-butanol extract equal to 5 spot with n-hexene : ethyl acetate (8:2( and Chloroform : methanol : water (10:6:0,5). Key words : Pharmacognostic , Myrmecodia pendens , Thin layer chromatography

Preliminary research of quality standard on Brassica rapa

To explore the physical and behavioral, microscopic and chemical characteristic traits of Brassica rapa, and supply scientific bases for establishing its quality control standard. Microscopic identification method was adopted to observe the microscopic characters of ten batches crude drugs, the contents of water, impurity, total ash, insoluble acid ash and extractives were detected based on Chinese Pharmacopoeia (2010) , and the oil constituents were analyzed by gas chromatography-mass spectrometry (GC-MS). The microscopic traits were cotyledon, palisade cells, non-glandular hairs and inner endosperm, while the palisade cells, cotyledon cells and non-glandular hairs existed in its powders. The results confirmed the contents of water, impurity, total ash and insoluble acid ash should be fewer than 6%, 4.5%, 6%, 0.7%, while the content of extractives should exceed 11%. The main oil compounds in it were erucic acid, oleic acid and gamma-sitosterol through the GC-MS analysis. The experimental methods were accurate and reliable, and the indexes and parameters may be thought as the quality standards for B. rapa.

Characterization of Za'tar (thyme) mixture

Introduction Five formulae of Za’tar mixtures were analysed to determine the characterization and identify the quality factors of this food product. Methods The formulae were based on differing mixtures of ingredients which affect the characteristics and qualities of the product. Results The averages of moisture, ash, oil, protein, crude fibre and available carbohydrate percentage for the tested mixtures were 4.21, 9.15, 6.86, 11, 8.5 and 60.2, respectively. The extracted essential oil content in Za’tar mixtures ranged from 2.7% in Jabali to 2.01% in Extra Za’tar. Salt, acidity, insoluble ash in hydrochloric acid, gross energy and density values were of higher formulae, containing less than 25% of thyme and 3% sumac. The overall acceptability of the Za’tar mixture showed Super and Jabali Za’tar mixtures which are high in thyme, sesame, sumac that are more preferred by the consumers. The overall acceptability as well as preference sensory tests correlated positively (P < 0.005) with both thyme and sumac which are the major ingredients in Za’tar mixtures. In contrast, all of the other components in the Za’tar mixture were negatively correlated (P < 0.005) with the overall panellist acceptability and preference. Conclusions Ingredients, proximate analysis, gross energy, insoluble acid ash, essential oil content, acidity, density, microscopic test and sensory properties can be used to measure the quality of this food product.

Characterization of Antioxidant Compounds and Antioxidant Activity of Indian Rice Varieties

The present work is aimed at characterisation of phenolic acids and rice bran oil (RBO) of Njavara, a medicinal red rice variety and other rice varieties. The antioxidant activities of the rice polyphenols were also studied by radical scavenging assay, reducing power and microsomal lipid peroxidation. Pigmented rice varieties (Njavara and Jyothi) had high antioxidant activities than non-pigmented variety (IR 64). Acetone extracts showed higher phenol content and antioxidant potency compared to methanol and ethanol extracts. Njavara showed higher reducing capability and higher soluble (15%–46%) and insoluble phenolic acids (51%–75%) compared to Jyothi and IR 64. An array of phenolic acids were identified, the major being ferulic and p-coumaric acid. The ferulic acid concentration of Njavara in soluble and insoluble form was 33%-66% and 51%–75% higher, respectively, than non-medicinal rice. Njavara RBO was a better source of tocopherols. However, oryzanol composition of Njavara was similar to Jyothi and IR 64.

Composition of Bark Fiber of Wild Pteroceltis tatarinowii in Daguisi National Forest Park

The compositions of bark fiber in 64 samples(2-3 year old branches) of wild Pteroceltis tatarinowii population in Daguisi National Forest Park,Hubei province were analyzed.Results showed that the average value of moisture,ash,cold water extraction,and hot water extraction was 8.267%,6.273%,24.025%,and 26.594%,respectively;of 1%NaOH extraction,benzene-alcohol extraction,holocellulose,and acid accumulator insoluble lignin was 60.904%,11.011%,56.759% and 9.698%,respectively;cellulose absorbance value was 0.373.The distribution of four indices,namely acid accumulator insoluble lignin,ash,cellulose absorbance,and 1%NaOH extraction,was near to normal distribution,but other variables had large skewness.The inter-correlations between moisture and 1%NaOH extraction,ash and acid accumulator insoluble lignin,holocellulose and acid accumulator insoluble lignin were significant(p 0.05).The inter-correlations between moisture and ash,moisture and hot water extraction,moisture and holocellulose,benzene-alcohol extraction and holocellulose,benzene-alcohol extracts and acid accumulator insoluble lignin were highly significant(p 0.01).The 64 samples could be divided into 23 groups with average linkage of 5.627,which showed high phenotypic diversity in the wild Pteroceltis tatarinowii population in Daguisi National Forest Park and its broad prospect of genetic improvement.

Purification and biochemical characterization of insoluble acid invertase (INAC-INV) from pea seedlings.

Invertase (EC 3.2.1.26) catalyzes the hydrolysis of sucrose into D-glucose and D-fructose. Insoluble acid invertase (INAC-INV) was purified from pea (Pisum sativum L.) by sequential procedures entailing ammonium sulfate precipitation, ion exchange chromatography, absorption chromatography, reactive green-19 affinity chromatography, and gel filtration. The purified INAC-INV had a pH optimum of 4.0 and a temperature optimum of 45 °C. The effects of various concentrations of Tris-HCl, HgCl(2), and CuSO(4) on the activities of the purified invertase were examined. INAC-INV was not affected by Tris-HCl and HgCl(2). INAC-INV activity was inhibited by 6.2 mM CuSO(4) up to 50%. The enzymes display typical hyperbolic saturation kinetics for sucrose hydrolysis. The K(m) and V(max) values of INAC-INV were determined to be 4.41 mM and 8.41 U (mg protein)(-1) min(-1), respectively. INAC-INV is a true member of the β-fructofuranosidases, which can react with sucrose and raffinose as substrates. SDS-PAGE and immunoblotting were used to determine the molecular mass of INAC-INV to be 69 kDa. The isoelectric point of INAC-INV was estimated to be about pH 8.0. Taken together, INAC-INV is a pea seedling invertase with a stable and optimum activity at lower acid pH and at higher temperature than other invertases.

Post-anthesis alternate wetting and moderate soil drying enhances activities of key enzymes in sucrose-to-starch conversion in inferior spikelets of rice

This study tested the hypothesis that a post-anthesis moderate soil drying can improve grain filling through regulating the key enzymes in the sucrose-to-starch pathway in the grains of rice (Oryza sativa L.). Two rice cultivars were field grown and two irrigation regimes, alternate wetting and moderate soil drying (WMD) and conventional irrigation (CI, continuously flooded), were imposed during the grain-filling period. The grain-filling rate and activities of four key enzymes in sucrose-to-starch conversion, sucrose synthase (SuSase), adenosine diphosphate-glucose pyrophosphorylase (AGPase), starch synthase (StSase), and starch branching enzyme (SBE), showed no significant difference between WMD and CI regimes for the earlier flowering superior spikelets. However, they were significantly enhanced by the WMD for the later flowering inferior spikelets. The activities of both soluble and insoluble acid invertase in the grains were little affected by the WMD. The two cultivars showed the same tendencies. The activities of SuSase, AGPase, StSase, and SBE in grains were very significantly correlated with the grain-filling rate. The abscisic acid (ABA) concentration in inferior spikelets was remarkably increased in the WMD and very significantly correlated with activities of SuSase, AGPase, StSase, and SBE. Application of ABA on plants under CI produced similar results to those seen in plants receiving WMD. Applying fluridone, an indirect inhibitor of ABA synthesis, produced the opposite effect. The results suggest that post-anthesis WMD could enhance sink strength by regulating the key enzymes involved, and consequently, increase the grain-filling rate and grain weight of inferior spikelets. ABA plays an important role in this process.

Electrophoretic deposition of chitosan–albumin and alginate–albumin films

Electrophoretic deposition methods have been developed for the fabrication of composite films containing biopolymers and bovine serum albumin (BSA). The mechanism of the deposition of chitosan–BSA films was based on electrophoresis of chitosan and BSA in acidic solutions, and co‐precipitation of insoluble chitosan and BSA in the high pH region at the cathode surface. The mechanism of the anodic deposition of alginic acid–BSA films was based on electrophoresis of alginate and BSA in basic solutions and precipitation of insoluble alginic acid and BSA in the low pH region at the anode surface. The deposition yield measurements and scanning electron microscopy investigations showed that the amount of the deposited material can be controlled by variation of the deposition time. Uniform films with thickness of 0–15 μm were obtained on conductive substrates. The films were studied by thermogravimetric analysis, differential thermal analysis and Fourier transform infrared spectroscopy.

Determination of insoluble soap in agricultural soil and sewage sludge samples by liquid chromatography with ultraviolet detection

We have developed a new analytical procedure for determining insoluble Ca and Mg fatty acid salts (soaps) in agricultural soil and sewage sludge samples. The number of analytical methodologies that focus in the determination of insoluble soap salts in different environmental compartments is very limited. In this work, we propose a methodology that involves a sample clean-up step with petroleum ether to remove soluble salts and a conversion of Ca and Mg insoluble salts into soluble potassium salts using tripotassium ethylenediaminetetraacetate salt and potassium carbonate, followed by the extraction of analytes from the samples using microwave-assisted extraction with methanol. An improved esterification procedure using 2,4-dibromoacetophenone before the liquid chromatography with ultraviolet detection analysis also has been developed. The absence of matrix effect was demonstrated with two fatty acid Ca salts that are not commercial and are never detected in natural samples (C₁₃:₀ and C₁₇:₀). Therefore, it was possible to evaluate the matrix effect because both standards have similar environmental behavior (adsorption and precipitation) to commercial soaps (C₁₀:₀) to C₁₈:₀). We also studied the effect of the different variables on the clean-up, the conversion of Ca soap, and the extraction and derivatization procedures. The quantification limits found ranged from 0.4 to 0.8 mg/kg. The proposed method was satisfactorily applied for the development of a study on soap behavior in agricultural soil and sewage sludge samples.

THE ORIGIN AND DEVELOPMENT OF SECONDARY SOMATIC EMBRYOS IN BANANA CV. NANJANGUD RASBALE (SILK GP. RASTHALI, AAB)

Studies were initiated to develop regeneration protocol through somatic embryogenesis in banana cv. Rasthali. Embryogenic callus and somatic embryos were generated with male flower buds on MS medium supplemented with 2,4-D (18.10 μM ), NAA (5.37 μM) and IAA (5.71 μM ) with 3% sucrose and 0.2% gelrite. After 6-8 months well developed somatic embryos were sub cultured on to MS supplemented with NAA (1.07 μM), Zeatin (0.23 μM) ,2-ip (0.60 μM) and kinetin (0. 46 μM) for further maturation. Plantlets were obtained when somatic embryos were cultured on MS with Morel vitamin, IAA (11.42 μM)), and BAP (2.22 μM). Formation secondary somatic embryos on the primary embryos were observed if the primary embryos were left in the induction media a little longer (8-9 months). Transparent, fragile, secondary buds emerged either on top of young globular embryos or on cotyledonary region of matured primary somatic embryos. Histological and histochemical studies were carried out to verify the mode of development of secondary somatic embryos on the primary somatic embryos and it revealed that the secondary embryos were formed directly on the epidermis of primary somatic embryos without intervening callus. The study has shown two modes of development of direct secondary embryogenesis. In the first mode, the secondary somatic embryos originated from single epidermal cells of the young globular primary embryos. In the second mode several epidermal cells of matured primary somatic embryo were involved in the formation of secondary somatic embryos. Localization of starch, total insoluble proteins and nucleic acids were seen in the secondary somatic embryos.

Chemical and bromatological characteristics of elephant grass silages with the addition of dried cashew stalk

The objective of this study was to evaluate the nutritive value of elephant grass (Pennisetum purpureum, Schum.) silages with the addition of 0, 4, 8, 12 and 16% dried cashew stalk (Anacardium occidentale L.) - DCS, based on the fresh matter. A randomized complete design with four replications was used. Twenty 210 L plastic drums were used as experimental silos. The levels were determined of the dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, ether extract (EE), total carbohydrates (TC), non-fibrous carbohydrates (NFC), neutral detergent insoluble nitrogen (NDIN,% total N), acid detergent insoluble nitrogen (ADIN, % total N), pH values, ammonia nitrogen (in percentage of the total nitrogen, N-NH3, % total N), lactic acid, acetic acid, butyric acid and propionic acid. Adding DCS resulted in higher values of DM, CP, EE, NFC, NDIN (% total N), ADIN (% total N), pH, lactic acid and propionic acid. On the other hand, with increasing DCS levels, a linear decline was observed in values of NDF, ADF, hemicellulose, ammonia nitrogen (% total N) and butyric acid. DCS did not show effect on the TC and acetic acid in the silages. As a result, up to 16% dehydrated cashew stalk may be added to elephant-grass silages, based on the fresh matter, to increase CP and NFC levels and decrease NDF and ADF and improve the fermentation patterns. It should be taken into account that higher NDIN and ADIN values may interfere in nitrogen availability and therefore in further DM intake.

Fatty acids do not stimulate enteroendocrine cells via particle sensing mechanisms

Lipid digestion and absorption are closely regulated to achieve maximal assimilation. Cholecystokinin (CCK) is the key regulator of the gastrointestinal responses to fat, and is secreted by enteroendocrine cells (EEC) in response to luminal free fatty acids. The mechanisms by which EEC sense fatty acids remain unresolved, but could be attractive targets in strategies aiming to alter food intake and digestion. Previous evidence suggested that aggregates of insoluble fatty acids were principally detected, rather than free fatty acids in solution. Supportive observations followed which demonstrated that latex microparticles of similar size to fatty acid aggregates also activated CCK secretion via a rise in intracellular calcium. However, in the current report we show that this effect of latex microparticles is not specific to EEC. Three other cell types exposed to the microparticles also responded with a rise in intracellular calcium, and this occurred independently of any ability to sense fatty acids. In addition, latex microparticles operate via entry of extracellular calcium whilst fatty acids stimulate release of calcium from intracellular stores. Therefore fatty acids do not act upon the same pathway as latex microparticles. Nonetheless activating nutrient sensing cells by non-nutrient luminal factors that are not absorbed from the gut remains a potentially novel means to manipulate gut function and satiety.

Magnetized carrier as novel drug delivery system

The aim of the present study was to determine the nutritional value of Phalaris minor seeds in comparison to conventional cereal grains. P. minor seeds had higher ether extract (6.3%), total ash (7.5%), acid insoluble ash (AIA, 4.5%), acid detergent fibre (ADF, 10.2%), cellulose (5.5%), acid detergent lignin (ADL, 2.0%), neutral detergent insoluble crude protein (NDICP, 4.0%) and acid detergent insoluble crude protein (ADICP, 2.7%) content in comparison to conventional cereal grains. The crude protein of P. minor seeds (12.3%) was similar to that of wheat (12.0%), but higher than other conventional cereal grains including maize (9.0%). The amino acid composition of P. minor seeds was more or less similar to conventional cereal grains. P. minor seeds had a superior mineral profile (Ca, P, Na, K, Mg, Fe, Cu, Zn and Mn) than conventional cereal grains. In vitro evaluation revealed that net gas production was lowest (P less than 0.05) in P. minor seeds (216.37 L/kg DM/24 h). The methane production (L/kg DM/24 h)from P. minor seeds (43.03)was lower (P less than 0.05) than that from wheat (54.33) and barley (57.35). The organic matter digestibility of P. minor seeds (83.27%) was similar to that of barley (81.69%).It was concluded that P. minor seeds could be considered as potential source of nutrients for livestock.

Mimicking Biological Systems through Modular Control of Solvation: A Synthetic Receptor that Binds in Both Water or Chloroform

Two receptors are described which are designed to complex barbiturates and cyanuric acids. The functional groups at the binding pocket are polar and are designed to enable guest exchange from water to occur by a dispersion of the host. One receptor has a charged binding pocket lined with two phosphate groups resembling a surfactant. Evidence for the partial extraction of diethylbarbituric acid from water is presented. The more polar guest sodium alloxan 5-f-sulfonatophenylhydrazone was not complexed. The receptors were both used to solubilise two insoluble bis-isocyanuric acids by forming 2:1 complexes in chloroform.

Lyso-phosphatidylethanolamine-enhanced phenylalanine ammonia-lyase and insoluble acid invertase in isolated radish cotyledons

Application of lyso-phosphatidylethanolamine (LPE) is purported to suppress fruit ripening and delay foliar senescence. However, the endogenous LPE response of plants is more typically associated with propagation of wound and stress signals. Experiments were therefore carried out to determine whether exogenous LPE could elicit defense responses in plants by determining the effect of this lyso-phospholipid on activity of two key metabolic enzymes and pathogenesis-related proteins viz phenylalanine ammonia-lyase (PAL; EC 4.3.1.5) and insoluble acid invertase (Ac INV; EC 3.2.1.26) in expanding cotyledons of Raphanus sativus L. cv. Cherry Belle (radish). Activity of both enzymes was increased following exposure of tissue to 18:0-LPE and the response was dose dependent. Soluble Ac INV activity was not enhanced by exogenous 18:0-LPE. Increased PAL activity appeared to coincide with a decline in phenolic acid content and a rise in sinapine and lignin. An increase in insoluble Ac INV by 18:0-LPE was associated with a reduction in sucrose concentration. However, levels of glucose and fructose were unaffected. In view of these findings it is proposed that applied LPE acts to co-ordinate carbohydrate partitioning locally to fulfill anabolic respiratory requirements associated with the propagation of systemic wound and stress responses. Furthermore, the impact of exogenous 18:0-LPE on insoluble Ac INV activity is discussed in relation to the proposed role of this enzyme in cytokinin-mediated senescence delay.