Tunable durian seed gum-derived eutectogel as a novel coating material: Rheological, thermal, textural and barrier properties for enhanced food preservation

As a promising green and sustainable coating material, gum was extracted from durian seed to produce eutectogel, which the properties were tunable using natural deep eutectic solvent (NADES). Ten different eutectogels were successfully synthesized using durian seed gum (DSG) and xanthan gum (XG) gelators at different composition (5, 10, 15 %) to gel choline chloride-glucose (1:1), choline chloride-fructose (1:2) and betaine-glucose-water (1:1:1) NADESs. Results revealed that eutectogel was non-Newtonian and weak gel material with excellent thermostability up to 200 °C. When the gum content increased, the resulted eutectogel showed higher viscosity, yield stress, hardness, gumminess, adhesiveness, and weight holding capacity. In overall, choline chloride-fructose (1:2) NADES and 10 % of DSG formed an excellent eutectogel which remained stable and compatible upon 12 weeks of storage. It displayed superior viscoelastic, texture, gases and moisture barrier properties which were beneficial for food coating application. This eutectogel was able to extend the shelf life of fresh-cut apples during storage with lower weight loss and higher total phenolic content (TPC). The potential future of this well-characterized tunable DSG-derived eutectogel includes, but not limited to, food and pharmaceutical industries, smart sensing, flexible wearable electronics, water purification, supercapacitors and batteries.

Comparative Study on Volatile Compounds and Taste Components of Different Durian Cultivars Based on GC-MS, UHPLC, HPAEC-PAD, E-Tongue and E-Nose

In order to comprehensively evaluate the aroma-active substances and taste components of durian, solid-phase microextraction combined with gas chromatography mass spectrometry (SPME/GC-MS), high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and ultra-high-performance liquid chromatography (UHPLC) were used to test the key components of three popular durian cultivars. A total of 27 volatile compounds, 5 sugars, 27 organic acids and 19 free amino acids were detected in Black Thorn (BT) durian. A total of 38 volatile compounds, 4 sugars, 27 organic acids and 19 free amino acids were detected in Monthong (MT) durian. A total of 36 volatile compounds, 4 sugars, 27 organic acids and 20 free amino acids were detected in Musang King (MK) durian. Finally, the flavor differences of the three durians were evaluated using electronic nose (e-nose) and electronic tongue (e-tongue), and different cultivars were classified through principal component analysis (PCA).

Isohemigossypolone: Antiophidic properties of a naphthoquinone isolated from Pachira aquatica Aubl

We investigated the antiophidic properties of isohemigossypolone (ISO), a naphthoquinone isolated from the outer bark of the Pachira aquatic Aubl. The inhibition of phospholipase A₂, coagulant, fibrinogenolytic, hemorrhagic and myotoxic activities induced by Bothrops pauloensis venom (Pb) was investigated. For this, we use samples resulting from the incubation of Pb with ISO in different concentrations (1:1, 1:5 and 1:10 w/w), we also evaluated the condition of treatment using ISO after 15 min of venom inoculation. The activities of phospholipase A₂, coagulant, fibrinogenolytic, hemorrhagic and myotoxic induced by the B. pauloensis venom were significantly inhibited when the ISO was pre-incubated with the crude venom. For in vivo neutralization tests, the results were observed even when the ISO was applied after 15 min of inoculation of the venom or metalloprotease (BthMP). Also, to identify the inhibition mechanism, we performed in silico assays, across simulations of molecular coupling and molecular dynamics, it was possible to identify the modes of interaction between ISO and bothropic toxins BmooMPα-I, Jararacussin-I and BNSP-7. The present study shows that naphthoquinone isohemigossypolone isolated from the P. aquatica plant inhibited part of the local and systemic damage caused by venom proteins, demonstrating the pharmacological potential of this compound in neutralizing the harmful effects caused by snakebites.

Identification of an Important Odorant Precursor in Durian: First Evidence of Ethionine in Plants

On the basis of the following data from the literature, we hypothesized the presence of ethionine in durian pulp: (1) the major odorants in terms of quantity as well as odor potency in durian pulp are ethanethiol and its derivatives; (2) genome analysis of durian assigned methionine γ-lyase (MGL), the enzyme that converts methionine to methanethiol, a key role for durian odor formation; and (3) MGL accepts not only methionine but also ethionine as a substrate. A targeted search by liquid chromatography-tandem mass spectrometry allowed us to confirm the presence of ethionine in durian pulp. Quantitation of ethionine in samples of different varieties (Monthong, Krathum, Chanee, and Kanyao) showed concentrations (621-9600 μg/kg) in the same range but below the methionine concentrations (16100-30200 μg/kg). During fruit ripening, the ethionine concentration increased as well as the ethanethiol concentration. Final evidence for the role of ethionine as an ethanethiol precursor was provided by demonstrating the formation of (²H₅)ethanethiol after adding (²H₅)ethionine to durian pulp.

Effect of Durio zibethinus rind polysaccharide on functional constipation and intestinal microbiota in rats

The prevalence of constipation increases rapidly with the increased pressure of some people's life, which seriously affects the quality of life in related patients. In this study, the improvement of functional constipation by Durio zibethinus Murr rind polysaccharide (DZMP) and the effects of DZMP on intestinal microbiota were investigated in a constipation model of Sprague-Dawley (SD) rats established by loperamide hydrochloride. Results showed that DZMP at 200 mg/kg could significantly (P < 0.05) increase the intestinal transit rate, motilin, gastrin, substance P levels and concentration of short-chain fatty acids (SCFAs), reduce the somatostatin levels and improve the gastrointestinal peristalsis of rats. Sequencing showed that the Lachnospiraceae-NK4A136-group in the rats given 200 mg/kg DZMP (16.07%) was significantly higher than that of the model group (10.13%), while the Desulfovibrio was lower (2.99%) than that of the model group (4.19%). Principal co-ordinates analysis (PcoA) revealed a significant difference in intestinal microbiota composition between the model group and the high-dose DZMP group (200 mg/kg). The results demonstrated that DZMP has a regulatory effect of treating functional constipation and regulating intestinal flora in rats.

Phyto-Mediated Photo Catalysed Green Synthesis of Silver Nanoparticles Using Durio Zibethinus Seed Extract: Antimicrobial and Cytotoxic Activity and Photocatalytic Applications

In the present study, we have developed a green approach for the synthesis of silver nanoparticles (DSAgNPs) using aqueous extract of Durio zibethinus seed and determined its antibacterial, photocatalytic and cytotoxic effects. Surface plasmon resonance confirmed the formation of DSAgNPs with a maximum absorbance (λ_max) of 420 nm. SEM and TEM images revealed DSAgNPs were spherical and rod shaped, with a size range of 20 nm and 75 nm. The zeta potential was found to be −15.41 mV. XRD and EDX analyses confirmed the nature and presence of Ag and AgCl. DSAgNPs showed considerable antibacterial activity, exhibited better cytotoxicity against brine shrimp, and shown better photocatalytic activity against methylene blue. Based on the present research work, it can be concluded that DSAgNPs could be used in the field of water treatment, pharmaceuticals, biomedicine, biosensor and nanotechnology in near future.

Rarasaponin-bentonite-activated biochar from durian shells composite for removal of crystal violet and Cr(VI) from aqueous solution

This paper presents the preparation of composite material and its application for the adsorption of crystal violet and Cr(VI) from aqueous solution onto acid-activated bentonite (AAB) and rarasaponin-bentonite-activated biochar from durian shells composite (RBAB). The influence of initial pH of the solution and the temperature of adsorption on the adsorbents adsorption performance was also studied. Langmuir and Freundlich models could represent the adsorption equilibria equally well. Thermodynamic parameters such as ∆G°, ∆H°, and ∆S° were evaluated based on the adsorption isotherms. The values of ∆G°, ∆H°, and ∆S° for crystal violet adsorption system demonstrate behavior contrary to the Cr(VI) adsorption system. Where crystal violet adsorption is preferred at high temperatures with q_max, value is 518.64 mg/L; while adsorption Cr(VI) is better at low temperature with q_max, value is 106.30 mg/L. Pseudo-first-order and pseudo-second-order kinetic models could represent the kinetic data well.

Insights into the Key Compounds of Durian (Durio zibethinus L. 'Monthong') Pulp Odor by Odorant Quantitation and Aroma Simulation Experiments

Sixteen compounds, previously identified as potent odorants by application of an aroma extract dilution analysis and the gas chromatography-olfactometry analysis of static headspace samples, were quantitated in the pulp of durians, variety Monthong, and odor activity values (OAVs) were calculated by dividing the concentrations obtained by the odor thresholds of the compounds in water. In combination with data recently reported for hydrogen sulfide and short-chain alkanethiols, OAVs > 1 were obtained for 19 compounds, among which ethyl (2S)-2-methylbutanoate (fruity; OAV 1700000), ethanethiol (rotten onion; OAV 480000), and 1-(ethylsulfanyl)ethane-1-thiol (roasted onion; OAV 250000) were the most potent, followed by methanethiol (rotten, cabbage; OAV 45000), ethane-1,1-dithiol (sulfury, durian; OAV 23000), and ethyl 2-methylpropanoate (fruity; OAV 22000). Aroma simulation and omission experiments revealed that the overall odor of durian pulp could be mimicked by only two compounds, namely, ethyl (2S)-2-methylbutanoate and 1-(ethylsulfanyl)ethane-1-thiol, when combined in their natural concentrations.

Phenolics from Durian Exert Pronounced NO Inhibitory and Antioxidant Activities

Durian, known as the king of fruits, is native to Southeast Asia and popular in many countries. Bioactivity-guided fractionation of the peel of durian was applied to determine its bioactive constituents. Four novel phenolics, along with 16 known, were purified and identified. Four novel phenolics were elucidated to be durianol A (1), durianol B (2), durianol C (3), and 5'-methoxy-7'-epi-jatrorin A (4), respectively. The antioxidant and NO inhibitory activities were evaluated for the isolated phenolics. Some phenolics showed significant antioxidant activity in the DPPH and superoxide anion radical scavenging capacity assay. Most of the phenolics revealed pronounced inhibitory effects on NO production in murine RAW 264.7 cells induced by LPS, which showed more potent NO inhibitory activity compared to indomethacin. The results strongly demonstrated that the phenolics may be partially responsible for durian's NO inhibitory activity.

Chemistry and Pharmacognosy of the Genus Durio

Durio is well known as one of the sources of seasonal fruit production in Southeast Asia with its center of diversity in Borneo. Thailand, Indonesia, and Malaysia are the main Durio producers in the world. Besides having much information about the utilization and benefit from its timber and fruits as a food substance, traditionally some parts of this plant, such as leaves, bark and root, can also be used for medical purposes. This review deals with chemical constituents and the biological activities of Durio plants.

Cempedak durian as a potential biosorbent for the removal of Brilliant Green dye from aqueous solution: equilibrium, thermodynamics and kinetics studies

Cempedak durian peel (CDP) was used to remove Brilliant Green (BG) dye from aqueous solution. The adsorption of BG onto CDP was studied as functions of contact time, pH, temperature, ionic strength and initial concentration. In order to understand the adsorption process and its mechanisms, adsorption isotherm and kinetics models were used. The experiments were done under optimized 2-h contact time and ambient pH. Adsorption study showed that the Langmuir model best fitted with experimental data, and the maximum adsorption capacity was determined as 0.203 mmol g(-1) (97.995 mg g(-1)). Adsorption kinetics followed the pseudo 2nd order model, and intraparticle diffusion is involved but not as the rate-limiting step while Boyd model suggests that film diffusion might be in control of the adsorption process. Fourier transform infrared (FTIR) analysis showed that OH, C=O, C=C and NH functional groups might be involved in the adsorption of BG onto CDP. Thermodynamic study suggested that the adsorption of BG onto CDP is endothermic with ΔH (o) value of 12 kJ mol(-1) and adsorption is feasible. Regeneration of CDP's ability to remove BG was also studied using three different washing solutions. NaOH (0.1 M) was not only sufficient to be used to regenerate CDP's ability to remove BG but also improved its adsorption capability.

Implications of partial conjugation of whey protein isolate to durian seed gum through Maillard reactions: foaming properties, water holding capacity and interfacial activity

This paper deals with the conjugation of durian seed gum (DSG) with whey protein isolate (WPI) through Maillard reactions. Subsequently, the functional properties of durian seed gum in the non-conjugated (control sample) and conjugated forms were compared with several commercial gums (i.e., Arabic gum, sodium alginate, kappa carrageenan, guar gum, and pectin). The current study revealed that the conjugation of durian seed gum with whey protein isolate significantly (p < 0.05) improved its foaming properties. In this study, the conjugated durian seed gum produced the most stable foam among all samples. On the other hand, the emulsion stabilized with the conjugated durian seed gum also showed more uniform particles with a larger specific surface area than the emulsion containing the non-conjugated durian seed gum. The conjugated durian seed gum showed significant different foaming properties, specific surface area, particle uniformity and water holding capacity (WHC) as compared to the target polysaccharide gums. The conjugated durian seed gum showed more similar functional properties to Arabic gum rather than other studied gums.

Secondary metabolites in durian seeds: oligomeric proanthocyanidins

Ethanolic extract of durian seeds was fractionated by reverse phase flash column chromatography and the fractions characterized by electrospray ionization mass spectroscopy. Among a few unknown compounds collected, oligomeric proanthocyanidins (OPCs) were found to be one of the main compounds. Based on this result, the OPCs were purified the first time from the durian seeds using standard procedures and gave a yield of 1.8 mg/g dry matter after fractionation by Sephadex LH-20 column. Structural analysis by ¹³C{¹H} NMR and ESI-MS spectra showed the presence of primarily B-type procyanidins with mainly epicatechin as the extension units, which was further verified by matrix assisted laser desorption/ionization–time of flight mass spectra (MALDI-TOF MS), which shows a distribution of dimers to decamers. In addition, hydroxylated peaks with molecular weight 16 units more than the poly-epicatechins represented significant peaks. We suggest this might be due to hydroxylation occurring under the MALDI-TOF MS conditions. Consistently, depolymerization with α-toluenethiol resulted in epicatechin thioether as the major product, but undetectable amount of gallocatechin or its α-toluenethiol derivatives. The oligomershave a mean degree of polymerization of 7.30.

Bombacaceae: a phytochemical review

CONTEXT

Bombacaceae is a small family of the order Malvales and contains about 28 genera and 200 species. Members of this family are not only showy ornamentals but they possess significant economical and commercial reputation as well. In addition, various plant parts of several species are widely used as foods and traditional medicines in many parts of the world.

OBJECTIVE

Chemical analyses of Bombacaceae species have recently yielded a number of important phytocompounds belonging to different classes. Hence, this work represents a comprehensive appraisal of the phytochemical studies conducted on Bombacaceae plants.

MATERIALS AND METHODS

Searches were conducted using electronic databases (e.g., Medline, Pubmed, Academic Journals, and Springer Link); general web searches were also undertaken using Google applying some related search terms "e.g., Bombacaceae, phytochemical studies of Bombacaeae plants, and chemical investigation of Bombacaeae", journals and scientific theses. The bibliographies of papers relating to the review subject were also searched for further relevant references.

RESULTS

Chemical investigations were concentrated primarily on certain species leaving fertile fields for further phytopharmacological research.

CONCLUSION

The reviewed findings present Bombacaceae species as an untapped reservoir of phytocompounds which may play a supportive role in the pharmaceutical field and will be of high chemotaxonomic value within this recently separated family.

Characterization of the major odor-active compounds in Thai durian ( Durio zibethinus L. 'Monthong') by aroma extract dilution analysis and headspace gas chromatography-olfactometry

An aroma extract dilution analysis applied on the volatile fraction isolated from Thai durian by solvent extraction and solvent-assisted flavor evaporation resulted in 44 odor-active compounds in the flavor dilution (FD) factor range of 1-16384, 41 of which could be identified and 24 that had not been reported in durian before. High FD factors were found for ethyl (2S)-2-methylbutanoate (fruity; FD 16384), ethyl cinnamate (honey; FD 4096), and 1-(ethylsulfanyl)ethanethiol (roasted onion; FD 1024), followed by 1-(ethyldisulfanyl)-1-(ethylsulfanyl)ethane (sulfury, onion), 2(5)-ethyl-4-hydroxy-5(2)-methylfuran-3(2H)-one (caramel), 3-hydroxy-4,5-dimethylfuran-2(5H)-one (soup seasoning), ethyl 2-methylpropanoate (fruity), ethyl butanoate (fruity), 3-methylbut-2-ene-1-thiol (skunky), ethane-1,1-dithiol (sulfury, durian), 1-(methylsulfanyl)ethanethiol (roasted onion), 1-(ethylsulfanyl)propane-1-thiol (roasted onion), and 4-hydroxy-2,5-dimethylfuran-3(2H)-one (caramel). Among the highly volatile compounds screened by static headspace gas chromatography-olfactometry, hydrogen sulfide (rotten egg), acetaldehyde (fresh, fruity), methanethiol (rotten, cabbage), ethanethiol (rotten, onion), and propane-1-thiol (rotten, durian) were found as additional potent odor-active compounds. Fourteen of the 41 characterized durian odorants showed an alkane-1,1-dithiol, 1-(alkylsulfanyl)alkane-1-thiol, or 1,1-bis(alkylsulfanyl)alkane structure derived from acetaldehyde, propanal, hydrogen sulfide, and alkane-1-thiols. Among these, 1-(propylsulfanyl)ethanethiol, 1-{[1-(methylsulfanyl)ethyl]sulfanyl}ethanethiol, and 1-{[1-(ethylsulfanyl)ethyl]sulfanyl}ethanethiol were reported for the first time in a natural product.

Influence of chemical extraction on rheological behavior, viscoelastic properties and functional characteristics of natural heteropolysaccharide/protein polymer from Durio zibethinus seed

In recent years, the demand for a natural plant-based polymer with potential functions from plant sources has increased considerably. The main objective of the current study was to study the effect of chemical extraction conditions on the rheological and functional properties of the heteropolysaccharide/protein biopolymer from durian (Durio zibethinus) seed. The efficiency of different extraction conditions was determined by assessing the extraction yield, protein content, solubility, rheological properties and viscoelastic behavior of the natural polymer from durian seed. The present study revealed that the soaking process had a more significant (p < 0.05) effect than the decolorizing process on the rheological and functional properties of the natural polymer. The considerable changes in the rheological and functional properties of the natural polymer could be due to the significant (p < 0.05) effect of the chemical extraction variables on the protein fraction present in the molecular structure of the natural polymer from durian seed. The natural polymer from durian seed had a more elastic (or gel like) behavior compared to the viscous (liquid like) behavior at low frequency. The present study revealed that the natural heteropolysaccharide/protein polymer from durian seed had a relatively low solubility ranging from 9.1% to 36.0%. This might be due to the presence of impurities, insoluble matter and large particles present in the chemical structure of the natural polymer from durian seed.

Effect of different purification techniques on the characteristics of heteropolysaccharide-protein biopolymer from durian (Durio zibethinus) seed

Natural biopolymers from plant sources contain many impurities (e.g., fat, protein, fiber, natural pigment and endogenous enzymes), therefore, an efficient purification process is recommended to minimize these impurities and consequently improve the functional properties of the biopolymer. The main objective of the present study was to investigate the effect of different purification techniques on the yield, protein content, solubility, water- and oil-holding capacity of a heteropolysaccharide-protein biopolymer obtained from durian seed. Four different purification methods using different chemicals and solvents (i.e., A (isopropanol and ethanol), B (isopropanol and acetone), C (saturated barium hydroxide), and D (Fehling solution)] to liberate the purified biopolymer from its crude form were compared. In most cases, the purification process significantly (p < 0.05) improved the physicochemical properties of heteropolysaccharide-protein biopolymer from durian fruit seed. The present work showed that the precipitation using isopropanol and acetone (Method B) resulted in the highest purification yield among all the tested purification techniques. The precipitation using saturated barium hydroxide (Method C) led to induce the highest solubility and relatively high capacity of water absorption. The current study reveals that the precipitation using Fehling solution (Method D) most efficiently eliminates the protein fraction, thus providing more pure biopolymer suitable for biological applications.

Performances of toluene removal by activated carbon derived from durian shell

In the effort to find alternative low cost adsorbent for volatile organic vapors has prompted this research in assessing the effectiveness of activated carbon produced from durian shell in removing toluene vapors. Durian shells were impregnated with different concentrations of H3PO4 followed by carbonization at 500 °C for 20 min under nitrogen atmosphere. The prepared durian shell activated carbon (DSAC) was characterized for its physical and chemical properties. The removal efficiency of toluene by DSAC was performed using different toluene concentrations. Results showed that the highest BET surface area of the produced DSAC was 1404 m2/g. Highest removal efficiency of toluene vapors was achieved by using DSAC impregnated with 30% of acid concentration heated at 500 °C for 20 min heating duration. However, there is insignificant difference between removal efficiency of toluene by DSAC and different toluene concentrations. The toluene adsorption by DSAC was better fitted into Freundlich model.

[Anti-HIV activities of extracts from Chinese medicinal fromula Liangcha]

OBJECTIVE

To screen and evaluate the anti-HIV activities of extracts from Chinese medicinal formula Liangcha.

METHODS

The anti-HIV-1 activities of extracts from Chinese medicinal formula Liangcha were evaluated by cytotoxicity assay,syncytium reduction assay, protection for HIV-1 induced lytic assay, and ELISA assay for HIV-1 p24 antigen expression. The primary mechanisms were investigated by fusion inhibition assay, inhibition of viral replication in HIV-1 chronically infected H9 cell and inhibition assay of HIV-1 RT activity.

RESULTS

The extracts from Chinese medicinal formula Liangcha exhibited potent and broad-spectrum anti-HIV-1 activity on different HIV-1 strains with EC50 range 12.74 -116.87 microg/mL, but weakly inhibited HIV-2 replication. Meantime, it was not significantly cytotoxic in several T lymphocytes cell lines with CC50 range 564.79 - 1699.22 microg/mL. The activity of recombinant HIV-1 reverse transcriptase was inhibited by extracts from Chinese medicinal formula Liangcha, inhibition rate more than 50% at the concentration of 5.3 microg/mL. It also weakly inhibited the cell-to-cell fusion in co-culture with EC50 of 101.94 microg/mL.

CONCLUSION

The extracts from Chinese medicinal formula Liangcha exhibited potent and broad-spectrum anti-HIV-1 activity on different HIV-1 strains in vitro. Its anti-HIV-1 mechanism might be inhibiting HIV-1 reverse transcriptase and cell entry.

[Cough-relieving, analgesic and antibiotic effects of durian shell extracts: a study in mice]

OBJECTIVE

To investigate the cough-relieving, analgesic and antibiotic effects of durian shell extract (DSE) in relieving cough and its analgesic and antibiotic effects.

METHODS

The effect of DSE in relieving cough was assessed in mice challenged with ammonia and SO(2) to induce coughing. The analgesic and antibiotic effects of DSE in mice were evaluated by hot plate test and twisting reaction induced by acetic acid, and by minimal inhibitory concentration (MIC) and disc-agar diffusion tests, respectively.

RESULTS

Compared with the control group, the mice treated with 300 and 900 mg/kg DSE showed significantly prolonged latency with decreased number of coughing induced by ammonia and SO(2), and the effect was dose-dependent. DSE markedly prolonged the latency and decreased the twisting number of the mice induced by acetic acid without affecting the pain threshold in hot plate test. DSE produced no significant inhibitory effects against Staphylococcus aureus, Staphylococcus epidermidis, or E. coli, and showed a week inhibition against Bacillus aeruginosus.

CONCLUSION

DSE shows obvious effect in relieving cough and produces better analgesic effect against chemical factor-induced pain than against physical agent-induced pain sensation. DSE has a moderate inhibitory effect against Bacillus aeruginosus.

Studies on the immunomodulatory effect of polysaccharide gel extracted from Durio zibethinus in Penaeus monodon shrimp against Vibrio harveyi and WSSV

Oral administration of polysaccharide gel (PG) in shrimp diets revealed immunostimulating potential and disease resistance in Penaeus monodon (black tiger shrimp). PG from the fruit-rind of Durio zibethinus has been characterized to be a pectic polysaccharide with immunomodulating and antibacterial activities. PG inhibited growth of the shrimp bacterial pathogen, Vibrio harveyi 1526, by agar diffusion and broth microdilution tests. Clear inhibition zones on agar plates were observed at the lowest PG concentration of 3.1 mg/ml, where minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for PG were 6.3 and 12.5 mg/ml, respectively. Each group of juvenile shrimps, initial mean body weight 0.29 +/- 0.04 g, was housed in a closed-recirculating treated water system and was fed with PG-supplemented diets containing 1, 2 and 3% PG or shrimp basal diet in the control group for 8 and 12 weeks. PG-supplemented diets did not contribute to the overall growth of black tiger shrimp. The immune response was evaluated by analysis of prophenoloxidase activity and total hemocyte count in the shrimp fed PG-supplemented diets for 12 weeks. Prophenoloxidase activity in shrimp fed the 1, 2 and 3% PG-supplemented diet and total hemocyte count in shrimp fed the 1 and 2% PG-supplemented diet were higher (P < 0.05) than those of the control group. The percent survival was higher in groups fed the 1-3% PG-supplemented diets in challenge tests with either white spot syndrome virus (WSSV) or the bacterium V. harveyi 1526 than that of the control group. Relative percent survival (RPS) values in groups fed the 2% PG-supplemented diet showed the highest RPS value for disease resistance of 100% (at Day 6) and 36% (at Day 4) in treated shrimp against viral and bacterial infection, respectively. Mortality of PG-supplemented diets in treated shrimps against WSSV infection was also found to be much lower (P < 0.05) than that of the control group.

Influences of pyrolysis condition and acid treatment on properties of durian peel-based activated carbon

Durian peel was used for the synthesis of activated carbon used for adsorption of Basic Green 4 dye. Activated carbon was synthesised under either nitrogen (N(2)) atmospheric or vacuum pyrolysis, followed by carbon dioxide (CO(2)) activation. The synthesised activated carbon then was treated with hydrochloric acid (HCl) solution. The results showed that activated carbon synthesised under vacuum pyrolysis exhibited better properties and adsorption capacities than that under nitrogen atmospheric pyrolysis. The HCl treatment improved properties and adsorption capacities of activated carbons. Pseudo-second-order kinetics well described the adsorption of Basic Green 4.

Glycemic index of common Malaysian fruits

The objective of the present study was to measure the glycemic index of durian, papaya, pineapple and water-melon grown in Malaysia. Ten (10) healthy volunteers (5 females, 5 males; body mass index 21.18+/-1.7 kg/m2) consumed 50 g of available carbohydrate portions of glucose (reference food) and four test foods (durian, papaya, pineapple and watermelon) in random order after an overnight fast. Glucose was tested on three separate occasions, and the test foods were each tested once. Postprandial plasma glucose was measured at intervals for two hours after intake of the test foods. Incremental areas under the curve were calculated, and the glycemic index was determined by expressing the area under the curve after the test foods as a percentage of the mean area under the curve after glucose. The results showed that the area under the curve after pineapple, 232+/-24 mmolxmin/L, was significantly greater than those after papaya, 147+/-14, watermelon, 139+/-8, and durian, 124+/-13 mmolxmin/L (p<0.05). Similarly, the glycemic index of pineapple, 82+/-4, was significantly greater than those of papaya, 58+/-6, watermelon, 55+/-3, and durian, 49+/-5 (p<0.05). The differences in area under the curve and glycemic index among papaya, watermelon and durian were not statistically significant. We conclude that pineapple has a high glycemic index, whereas papaya is intermediate and watermelon and durian are low glycemic index foods. The validity of these results depends on the accuracy of the data in the food tables upon which the portion sizes tested were based.

Comparative study of health properties and nutritional value of durian, mangosteen, and snake fruit: experiments in vitro and in vivo

In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus Murr.) were compared with snake fruit (Salacca edulis Reinw.) and mangosteen (Garcinia mangostana). Dietary fibers, minerals, and trace metals were comparable. Total polyphenols (mg of GAE/100 g of FW) and flavonoids (85.1+/-6.1) were significantly higher (p<0.05) than in snake fruit (217.1+/-13.2 (mg of CE/100 g of FW)), durian (309.7+/-19.3 and 61.2+/-4.9), and mangosteen (190.3+/-12.1 and 54.1+/-3.8). Antioxidant activity (microM TE/100 g of FW) of durian measured by DPPH and ABTS assays (228.2+/-13.4 and 2016.3+/-81.1) was significantly higher (p<0.05) than in snake fruit (110.4+/-7.9 and 1507.5+/-70.1) and mangosteen (79.1+/-5.9 and 1268.6+/-62.3). HPLC/DAD analysis of durian (microg/100 g of FW) showed that quercetin (1214.23+/-116.7) was present at levels three times that of caffeic acid, and twice as high as p-coumaric and cinnamic acids. The correlation coefficients between the bioactive compounds of fruits and their antioxidant activities were high (R2=0.99). Male Wistar rats (25) were divided into five dietary groups: the control group was fed the basal diet (BD); in addition to BD, the cholesterol (Chol) group was supplemented with 1% of Chol; the diets of the Chol/Durian, Chol/Snake, and Chol/Mangosteen groups were supplemanted with 5% of these fruits, respectively. It was found that diets supplemented with durian, and to a lesser degree with snake fruit and mangosteen, significantly hindered the rise in plasma lipids and the decrease in antioxidant activity. The nutritional values were comparably high. In conclusion, it could be suggested that inclusion of studied tropical fruits, especially durian, in known disease-preventing diets could be beneficial.

Secondary metabolites from the wood bark of Durio zibethinus and Durio kutejensis

Phytochemical exploration of a wood bark extract from Durio zibethinus afforded two new triterpenoids, namely, methyl 27-O-trans-caffeoylcylicodiscate (1) and methyl 27-O-cis-caffeoylcylicodiscate (2), a new phenolic, 1,2-diarylpropane-3-ol (3), and seven known compounds, fraxidin, eucryphin, boehmenan, threo-carolignan E, (-)-(3R,4S)-4-hydroxymellein, methyl protocatechuate, and (+)-(R)-de-O-methyllasiodiplodin (4). In addition, chemical analysis of a wood bark extract from Durio kutejensis yielded the new triterpenes 3beta-O-trans-caffeoyl-2alpha-hydroxyolean-12-en-28-oic acid (5) and 3beta-O-trans-caffeoyl-2alpha-hydroxytaraxest-12-en-28-oic acid (6) together with four known compounds, maslinic acid, arjunolic acid, 2,6-dimethoxy-p-benzoquinone, and fraxidin. The structures of all compounds were determined on the basis of spectroscopic data.

2-O-methylisohemigossylic acid lactone, a sesquiterpene, isolated from roots of mokumen (Gossampinus malabarica) induces cell death and morphological change indicative of apoptotic chromatin condensation in human promyelotic leukemia HL-60 cells

2-O-methylisohemigossylic acid lactone, a sesquiterpene, was purified from roots of mokumen (Gossampinus malabarica) and identified by Mass, and (1)H- and (13)-NMR. This sesquiterpene displayed strong growth inhibitory effect against human promyelotic leukemia HL-60 cells. Apoptotic morphological change of the nucleus, including chromatin condensation was induced in the HL-60 cells treated with the sesquiterpene. The fragmentation of DNA by the sesquiterpene to oligonucleosomal-sized fragments, a characteristic of apoptosis, was observed to be dose- and time-dependent in the HL-60 cells. Inhibitors of caspases suppressed the DNA fragmentation induced by the sesquiterpene. These findings suggest that growth inhibition by the sesquiterpene of HL-60 cells results from the induction of apoptosis by the sesqui-terpene, and that caspase cascade is involved in the induction of apoptosis by the compound in the HL-60 cells.

Syntheses of (−)-Funebrine and (−)-Funebral, Using Sequential Transesterification and Intramolecular Cycloaddition of a Chiral Nitrone

The first syntheses of (-)-funebrine [(-)-1] and (-)-funebral [(-)-2] are described. The syntheses feature sequential formation of nitrone VI from methyl glyoxylate (5) with oxime 6, transesterification of nitrone VI with (E)-crotyl alcohol (4), and intramolecular cycloaddition of the resulting nitrone VII bearing crotyl ester to afford cycloadduct 7 as a major product. The adduct 7 was readily elaborated to amino lactone (-)-3, the key synthetic intermediate of (-)-1 and (-)-2.

Induction of apoptosis by lupeol isolated from mokumen (Gossampinus malabarica L. Merr) in human promyelotic leukemia HL-60 cells

We have investigated the effect of lupeol (lup-20(29)-ene-3beta-ene-3-ol) isolated from mokumen (Gossampinus malabarica L. Merr) on DNA of human promyelotic HL-60 leukemia cells. Induction of apoptosis by lupeol was observed in human leukemia HL-60 cells. Morphological change showing apoptotic bodies was observed in the HL-60 cells treated with lupeol. The fragmentation of DNA by lupeol to oligonucleosomal-sized fragments that is a characteristic of apoptosis was observed to be concentration- and time-dependent in the HL-60 cells. Flow cytometric analysis showed that the hypodiploid nuclei of HL-60 cells were increased to 28.5, 42.0 and 70.9% after a 3-day treatment with 75, 100 and 150 micro M lupeol, respectively. The data of the present study show that the suppression by lupeol of growth of the HL-60 cells results from the induction of apoptosis by this compound.