RESUMO
Wax apple is one of the underutilized fruits that is considered a good source of fibers, vitamins, minerals as well as antioxidants. In this study, a comparative analysis of the developments of wax fruit ripening at the proteomic and metabolomic level was reported. 2D electrophoresis coupled with MALDI-TOF/TOF was used to compare the proteome profile from three developmental stages named immature, young, and mature fruits. In general, the protein expression profile and the identified proteins function were discussed for their potential roles in fruit physiological development and ripening processes. The metabolomic investigation was also performed on the same samples using quadrupole LC-MS (LC-QTOF/MS). Roles of some of the differentially expressed proteins and metabolites are discussed in relation to wax apple ripening during the development. This is the first study investigating the changes in the proteins and metabolites in wax apple at different developmental stages. The information obtained from this research will be helpful in developing biomarkers for breeders and help the plant researchers to avoid wax apple cultivation problems such as fruit cracking.
Assuntos
Frutas , Metabolômica/métodos , Proteômica/métodos , Syzygium , Biomarcadores , Cromatografia Líquida , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteínas de Plantas/análise , Proteínas de Plantas/metabolismo , Mapas de Interação de Proteínas , Syzygium/química , Syzygium/crescimento & desenvolvimento , Syzygium/metabolismo , Espectrometria de Massas em TandemRESUMO
Oxidation is a major cause of protein quality deterioration during the storage and processing of food. This study investigated the effects of clove extract (CE) on structural and rheological changes in porcine longissimus myofibrillar proteins (MP) and the effects of oxidizing radicals produced by a Fenton reaction system (FRS). Increased oxidation time was accompanied by increased carbonyl content, reduced Ca-ATPase activity, decreased enthalpy of denaturation, decreased thermal transition temperatures (P<0.05), and increased protein susceptibility to thermal aggregation. The addition of CE significantly inhibited carbonyl formation (P<0.05), enhanced solubility and thermal stability, and improved the gel formation ability (storage modulus, loss modulus) of MP. The protective effect of CE on protein denaturation was demonstrated by its efficacy in maintaining Ca-ATPase activity and decreasing the degree of protein aggregation. Overall, the hydroxyl radical-induced loss of the structural and functional properties of MP was significantly reduced by the presence of CE.
Assuntos
Antioxidantes/química , Proteínas Alimentares/química , Conservantes de Alimentos/química , Carne/análise , Proteínas Musculares/química , Extratos Vegetais/química , Syzygium/química , Animais , Antioxidantes/isolamento & purificação , Varredura Diferencial de Calorimetria , China , Proteínas Alimentares/análise , Proteínas Alimentares/isolamento & purificação , Flores/química , Flores/crescimento & desenvolvimento , Conservantes de Alimentos/isolamento & purificação , Géis , Radical Hidroxila/análise , Radical Hidroxila/antagonistas & inibidores , Radical Hidroxila/química , Carne/economia , Proteínas Musculares/análise , Proteínas Musculares/isolamento & purificação , Oxirredução , Extratos Vegetais/isolamento & purificação , Carbonilação Proteica , Conformação Proteica , Estabilidade Proteica , Reologia , Solubilidade , Sus scrofa , Syzygium/crescimento & desenvolvimento , Temperatura de Transição , ViscosidadeRESUMO
Despite the various reports on the pharmacology of Clove bud [Syzygium aromaticum]-derived essential oil and its major component eugenol, systematic information on the bioactivity of clove polyphenols is very limited. Clove buds being one of the richest sources of dietary polyphenols with many traditional medicinal uses, the present contribution attempted to derive their standardized polyphenol-rich extracts as a water soluble free flowing powder (Clovinol) suitable for functional food applications, without the issues of its characteristic pungency and aroma. The extract was characterized by electrospray ionization-time of flight mass spectrometry (ESI-TOF-MS), and investigated for in vivo antioxidant, anti-inflammatory and anti-ulcerogenic activities. Clovinol showed significant antioxidant and anti-inflammatory effects as measured by cellular antioxidant levels, and the ability to inhibit carrageenan-induced paw swelling in mice. Further investigations revealed its significant anti-ulcerogenic activity (>97% inhibition of ethanol-induced stomach ulcers in Wistar rats when orally administered at 100 mg per kg b.w.) and up regulation of in vivo antioxidants such as superoxide dismutase (SOD), glutathione (GSH), and catalase (CAT). Clovinol also reduced the extent of lipid peroxidation among ulcer induced rats, indicating its usefulness in ameliorating oxidative stress and improving gastrointestinal health, especially upon chronic alcohol consumption. The extract was also shown to be safe and suitable for further investigations and development upon acute toxicity studies at 5 g per kg body weight and 28 days of repeated dose toxicity studies at 2.5 g per kg b.w.
Assuntos
Antiulcerosos/uso terapêutico , Suplementos Nutricionais , Flores/química , Extratos Vegetais/uso terapêutico , Polifenóis/uso terapêutico , Úlcera Gástrica/prevenção & controle , Syzygium/química , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/metabolismo , Anti-Inflamatórios não Esteroides/uso terapêutico , Antiulcerosos/administração & dosagem , Antiulcerosos/efeitos adversos , Antiulcerosos/metabolismo , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Suplementos Nutricionais/efeitos adversos , Etnofarmacologia , Feminino , Flores/crescimento & desenvolvimento , Mucosa Gástrica/imunologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Índia , Masculino , Medicina Tradicional , Camundongos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/efeitos adversos , Extratos Vegetais/metabolismo , Polifenóis/administração & dosagem , Polifenóis/efeitos adversos , Polifenóis/metabolismo , Distribuição Aleatória , Ratos Wistar , Úlcera Gástrica/dietoterapia , Úlcera Gástrica/imunologia , Úlcera Gástrica/patologia , Syzygium/crescimento & desenvolvimento , Testes de Toxicidade Aguda , Testes de Toxicidade SubagudaRESUMO
An efficient method for cloning Syzygium cumini (above 40 years old) through mature nodal segments has been successfully developed and that could be exploited for large-scale production of this valuable multipurpose tree. Nodal segments from mature tree were taken as explants and cultured on MS basal medium with different cytokinins (BA, Kin, AdS). The application of BA proved to be the best responsive cytokinin for the induction of shoot buds and shoots, but the proliferated shoots exhibited slower and stunted growth accompanied with abscission of leaves and shoot tip necrosis (STN). The problem of leaf abscission and STN was considerably reduced by the application of an adjuvant, adenine sulphate (AdS) in the optimal medium which led to the production of a maximum of 14 shoots. Further improvement in shoot bud regeneration and improved growth pattern of the regenerating tissue was obtained on the media comprised of MS + BA (10 µM) + GA3 (2.5 µM). A total number of 15 shoots with mean shoot length of 5.9 cm was obtained. The healthy elongated shoots were then rooted on MS basal augmented with NAA (5 µM). The plantlets obtained were healthy and were successfully acclimatized and transferred under field condition with 70 % survival rate.
Assuntos
Adenina/metabolismo , Técnicas de Cultura de Células/métodos , Sulfatos/metabolismo , Syzygium/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Técnicas de Cultura de Células/instrumentação , Meios de Cultura/metabolismo , Citocininas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Árvores/metabolismoRESUMO
BACKGROUND: Syzygium aromaticum (L.) Merr. & Perry (clove) bud is an important spice used in the preparation of several delicacies and in folklore for diabetes management. The present study was convened to assess the effects of dietary clove bud powder (CBP) on biochemical parameters in a type 2 diabetes rat model, induced by a combination of high-fat diet and low-dose streptozotocin (35 mg kg⻹) for 30 days. RESULTS: Diabetic rats were placed on dietary regimen containing 20-40 g kg⻹ clove bud powder. The results revealed that there was no significant (P > 0.05) difference in the average feed intake and weight changes between the rat groups. Furthermore, supplementation with CBP gradually reduced blood glucose level in diabetic rat compared to control diabetic rats without CBP supplementation (DBC). Moreover, reduced activity of α-glucosidase was observed in CBP and metformin-treated rat groups when compared to that of the DBC rat group. In addition, the DBC group had significantly (P < 0.05) higher lipid concentrations (except for high-density lipoprotein cholesterol) when compared to all other groups. Furthermore, CBP had significantly (P < 0.05) reduced activity of liver enzymes (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase) and showed elevated levels of antioxidant status (glutathione, ascorbic acid, superoxide dismutase and catalase). CONCLUSION: The results suggest that the clove bud diet may attenuate hyperglycemia, hyperlipidemia, hepatotoxicity and oxidative stress in the type 2 diabetic condition.
Assuntos
Diabetes Mellitus Tipo 2/dietoterapia , Suplementos Nutricionais , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Preparações de Plantas/uso terapêutico , Syzygium/química , Animais , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/uso terapêutico , Biomarcadores/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Etnofarmacologia , Flores/química , Flores/crescimento & desenvolvimento , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/efeitos adversos , Hipolipemiantes/administração & dosagem , Hipolipemiantes/efeitos adversos , Lipotrópicos/administração & dosagem , Lipotrópicos/efeitos adversos , Lipotrópicos/uso terapêutico , Fígado/enzimologia , Fígado/metabolismo , Fígado/fisiopatologia , Masculino , Medicinas Tradicionais Africanas , Nigéria , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Estresse Oxidativo , Fitoterapia/efeitos adversos , Preparações de Plantas/administração & dosagem , Preparações de Plantas/efeitos adversos , Distribuição Aleatória , Ratos Wistar , Syzygium/crescimento & desenvolvimentoRESUMO
2',4'-Dihydroxy-6'-methoxy-3',5'-dimethylchalcone (DMC) is a chalcone isolated from the buds of Cleistocalyx operculatus (Roxb.) Merr. et Perry, and the hepatoprotective effects of DMC on Kunming mice have been studied in previous study. However, the effects of DMC on hepatocyte toxicity and corresponding mechanism remain unclear. The aim of this study was to evaluate the hepatoprotective mechanism of DMC in human hepatocytes (L02) treated with H2O2. The results demonstrated that pretreatment with DMC effectively protected H2O2-induced cell viability loss, cell membrane damage (lactate dehydrogenase, nitric oxide production and caspase-3 accumulation. Besides, DMC pretreatment increased the amount of glutathione, decreased malondialdehyde and the percentage of apoptotic L02 cells compared with only H2O2 treated group. Taken together, these results indicated that DMC had hepatoprotective effects against H2O2-induced liver injury by alleviating oxidative stress and apoptosis process in L02 cells, and DMC might be a potential candidate for the intervention of liver diseases.
Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Chalconas/farmacologia , Hepatócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Caspase 3/química , Caspase 3/metabolismo , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Etnofarmacologia , Flores/química , Flores/crescimento & desenvolvimento , Glutationa/agonistas , Glutationa/metabolismo , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/toxicidade , Medicina Tradicional Chinesa , Óxido Nítrico/metabolismo , Concentração Osmolar , Oxidantes/antagonistas & inibidores , Oxidantes/toxicidade , Syzygium/química , Syzygium/crescimento & desenvolvimentoRESUMO
One of the most commonly cited hypotheses explaining invasion success is the enemy release hypothesis (ERH), which maintains that populations are regulated by coevolved natural enemies where they are native but are relieved of this pressure in the new range. However, the role of resident enemies in plant invasion remains unresolved. We conducted a field experiment to test predictions of the ERH empirically using a system of native, introduced invasive, and introduced non-invasive Eugenia congeners in south Florida. Such experiments are rarely undertaken but are particularly informative in tests of the ERH, as they simultaneously identify factors allowing invasive species to replace natives and traits determining why most introduced species are unsuccessful invaders. We excluded insect herbivores from seedlings of Eugenia congeners where the native and invasive Eugenia co-occur, and compared how herbivore exclusion affected foliar damage, growth, and survival. We found no evidence to support the ERH in this system, instead finding that the invasive E. uniflora sustained significantly more damage than the native and introduced species. Interestingly, E. uniflora performed better than, or as well as, its congeners in terms of growth and survival, in spite of higher damage incidence. Further, although herbivore exclusion positively influenced Eugenia seedling survival, there were few differences among species and no patterns in regard to invasion status or origin. We conclude that the ability of E. uniflora to outperform its native and introduced non-invasive congeners, and not release from insect herbivores, contributes to its success as an invader in Florida.
Assuntos
Herbivoria , Espécies Introduzidas , Plântula/crescimento & desenvolvimento , Syzygium/crescimento & desenvolvimento , Animais , Florida , InsetosRESUMO
BACKGROUND: The use of plants and their derived substances increases day by day for the discovery of therapeutic agents owing to their versatile applications. Current research is directed towards finding naturally-occurring antioxidants having anticancer properties from plant origin since oxidants play a crucial role in developing various human diseases. The present study was designed to investigate the antioxidant and anticancer properties of Sygygium fruticosum (Roxb.) (abbreviated as SF). METHODS: The dried coarse powder of seeds of SF was exhaustively extracted with methanol and the resulting crude methanolic extract (CME) was successively fractionated with petroleum ether, chloroform and ethyl acetate to get petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF) and lastly aqueous (AQF) fraction. The antioxidant activities were determined by several assays: total antioxidant capacity assay, DPPH free radical scavenging assay, hydroxyl radical scavenging assay, ferrous reducing antioxidant capacity and lipid peroxidation inhibition assay. The in vivo anticancer activity of SF was determined on Ehrlich's Ascite cell (EAC) induced Swiss albino mice. RESULTS: All the extractives showed strong antioxidant activities related to the standard. The total antioxidant capacity (TAC) of the fractions was in the following order: EAF>AQF>CME>PEF>CHF. The TAC of EAF at 320 µg/mL was 2.60±0.005 which was significantly higher (p < 0.01) than that of standard catechin (1.37 ± 0.005). The ferrous reducing antioxidant capacity of the extracts was in the following order: EAF>AQF>CME>AA>CHF>PEF. In DPPH free radical scavenging assay, the IC50 value of EAF was 4.85 µg/mL, whereas that of BHT was 9.85 µg/mL. In hydroxyl radical scavenging assay and lipid peroxidation inhibition assay, the EAF showed the most potent inhibitory activity with IC50 of 43.3 and 68.11 µg/mL, respectively. The lipid peroxidation inhibition assay was positively correlated (p < 0 .001) with both DPPH free radical scavenging and hydroxyl radical scavenging assay. The total phenolic contents of SF were also positively correlated (p < 0 .001) with DPPH free radical scavenging, hydroxyl radical scavenging and lipid peroxidation inhibition assay. Based on antioxidant activity, EAF was selected for cytotoxic assay and it was found that EAF inhibited 67.36% (p < 0.01) cell growth at a dose of 50 mg/kg (ip) on day six of EAC cell incubation. CONCLUSIONS: Our results suggest that EAF of seeds of SF possess significant antioxidant and moderate anticancer properties. Seeds of SF may therefore be a good source for natural antioxidants and a possible pharmaceutical supplement.
Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antioxidantes/administração & dosagem , Extratos Vegetais/administração & dosagem , Sementes/química , Syzygium/química , Animais , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Bangladesh , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos , Extratos Vegetais/química , Sementes/crescimento & desenvolvimento , Syzygium/crescimento & desenvolvimentoRESUMO
In the last few years there has been an exponential growth in the field of herbal medicine, and these drugs are gaining popularity in both developing and developed countries because of their natural origin and lesser side effects. Syzygium cumini (syn. Eugenia jambolana, Syzygium jambolana, Eugenia cumini, Syzygium jambos), commonly known as jamun in India, is an evergreen tree distributed throughout the Indian subcontinent, Southeast Asia and East Africa. It is mainly utilised as a fruit producer and for its timber. Medicinally, the fruit is reported to have antidiabetic, antihyperlipidaemic, antioxidant, antiulcer, hepatoprotective, antiallergic, antiarthritic, antimicrobial, anti-inflammatory, antifertility, antipyretic, antiplaque, radioprotective, neuropsychopharmacological, nephroprotective and antidiarrhoeal activities. Among these beneficial physiological effects, the antidiabetic property of S. cumini has the most promising nutraceutical value. The health-beneficial effects of S. cumini are mainly attributed to various phytoconstituents such as tannins, alkaloids, steroids, flavonoids, terpenoids, fatty acids, phenols, minerals, carbohydrates and vitamins present in the fruit. This review paper presents an overview of experimental evidence for the pharmacological potential of S. cumini.
Assuntos
Compostos Fitoquímicos/farmacologia , Syzygium/química , África Oriental , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Sudeste Asiático , Descoberta de Drogas , Etnofarmacologia , Frutas/química , Humanos , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Hipolipemiantes/isolamento & purificação , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Índia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/uso terapêutico , Casca de Planta/química , Folhas de Planta/química , Sementes/química , Syzygium/crescimento & desenvolvimentoRESUMO
This study aims to analyze the maturation and dispersal of Eugenia pyriformis Cambess. seeds produced in different years, and the influence of variation in thermal and hydric environment on seed physical and physiological characteristics at dispersal. Fruits at different developmental stages were harvested in the city of São Paulo between 2003 and 2010, as well as in the cities of Campinas and Lavras, in 2009 and 2010 and analyzed for size and color. The seeds were extracted from the fruits and their dry mass, water content, germination and vigor were assessed. Results showed that seed maturation is unsynchronized to the maturation of the fruit, taking 45 days on average (430 growing degree-days), longer in rainy times or lower temperatures. Seeds with higher physiological quality were produced in rainy years and when the temperature range was larger. We concluded therefore that hydric and thermal environmental variations during development influence the maturation of Eugenia pyriformis seeds and are able to determine the formation cycle and the final seed quality.
Assuntos
Germinação/fisiologia , Sementes/crescimento & desenvolvimento , Syzygium/crescimento & desenvolvimento , Syzygium/classificação , Temperatura , ÁguaRESUMO
Balady cultivar and six Chinese lines were planted to study their developmental growth, yield and essential oil variations. Bulb of Balady cultivar had more two folds of cloves number per bulb than the Chinese lines. On the contrary Balady cv had the lowest clove weight compared to all Chinese lines. Chinese lines significantly surppassed the Balady cultivar in the bulb yield ha(-1). The bulb yield ha(-1) could be arrangement in descending order as follow Line B > Line F > Line D > Line C > Line A > Line E > Balady cv. Line B significantly surpassed the other tested lines in oil yield and had 7 folds oil yield plant(-1) than the local cultivar. The main compound in the bulb was found to be methylallay disulfide in both Chinese lines and Balady cultivar. Some components which found in the garlic bulbs at the age 150 days disappeared at the maturity time. Chinese Line B recorded the highest bulb yield and volatile oil content comparing with other lines.
Assuntos
Alho/crescimento & desenvolvimento , Alho/metabolismo , Óleos Voláteis/metabolismo , Óleos de Plantas/metabolismo , Syzygium/crescimento & desenvolvimento , Syzygium/metabolismoRESUMO
Fungal colonization of litter has been described mostly in terms of fructification succession in the decomposition process or the process of fungal ligninolysis. No studies have been conducted on litter colonization by arbuscular mycorrhizal fungi (AMF) and their relationship with the presence of saprotrophic fungi. The aim of the present study was to evaluate the relationships that exist in simultaneous leaf litter colonization by AMF and saprotrophic fungi and the relationships between rates of litter and associated root colonization by AMF at different soil depths. We selected Eugenia sp. and Syzygium sp. in a riparian tropical forest, with an abundant production of litter (O horizon), we evaluated litter and root colonization at different depths, its C:N ratios, and the edaphic physico-chemical parameters of the A horizon immediately below the litter layer. Litter colonization by saprotrophic fungi and AMF increased with depth, but the saprotrophic fungal colonization of some litter fragments decreased in the lowermost level of the litter while AMF litter colonization continued to increase. Plant roots were present only in the middle and bottom layers, but their mycorrhizal colonization did not correlate with litter colonization. The external hyphae length of AMF is abundant (ca. 20 m g(-1) sample) and, in common with sample humidity, remained constant with increasing depth. We conclude that in zones of riparian tropical forest with abundant sufficient litter accumulation and abundant AMF external hyphae, the increase in litter colonization by AMF with depth correlates to the colonization by saprotrophic fungi, but their presence in the deepest layers is independent of both litter colonization by saprotrophic fungi and root colonization by AMF.
Assuntos
Raízes de Plantas/microbiologia , Microbiologia do Solo , Syzygium/crescimento & desenvolvimento , Hifas/crescimento & desenvolvimento , Árvores , Clima TropicalRESUMO
The biotransformation of [14C]4-n-nonylphenol (5 mg l(-1); 10 mg l(-1)) by Agrostemma githago cell suspensions was studied using a batch two-liquid-phase system (medium/n-hexadecane 200:1, v/v). The highly lipophilic 4-n-nonylphenol was applied via n-hexadecane phase. After 7 d of incubation, more than 85% of applied 4-n-nonylphenol was absorbed by the cells, and 40% was transformed to 10 side-chain monohydroxylated metabolites (two with additional double bond at side-chain). The primary metabolites were analyzed by GC-EIMS. In the cells, the monohydroxylated products and residual 4-n-nonylphenol were present as glycosides. The method proved to be suitable for the production of primary metabolites of 4-n-nonylphenol on a larger scale for identification purposes and for metabolic profiling of the compound.
Assuntos
Fenóis/metabolismo , Syzygium/crescimento & desenvolvimento , Syzygium/metabolismo , Biotransformação , Radioisótopos de Carbono , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Resíduos Industriais/prevenção & controleRESUMO
Iron has proved to be an integral component of the culture medium supporting the caulogenic response of the epicotyl segments of S. cuminii. In the absence of both the iron and EDTA even the shoot buds failed to develop, while in the presence of either of these, though the shoot buds developed, their elongation was adversely affected. Among the three iron sources tested, ferrous sulphate proved to be the best, as the ferric chloride was not as effective as the former when used either alone or along with EDTA. Ferric citrate, on the other hand, when provided alone, elicited better response than that induced by ferrous sulphate alone. However, in combination with EDTA, the response declined significantly. The estimation of endogenous levels of iron in the explants further supported these results. The quantum of iron absorption was at a maximum during the first week of the culture and the explants, once deprived of iron during the first week, failed to catch up to the level of iron accumulated in the explants maintained continuously on complete medium, even after transfer to the complete medium. Likewise, the level of copper ions did not come up to comparable levels even if the explants were transferred to the complete medium after initial deprivation.