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  1. Fulltext Evaluation of antioxidant compounds, antioxidant activities, and mineral composition of 13 collected purslane (Portulaca oleracea L.) accessions
    Alam MA, Juraimi AS, Rafii MY, Abdul Hamid A, Aslani F, Hasan MM, et al.
    Biomed Res Int, 2014;2014:296063.
    PMID: 24579078 DOI: 10.1155/2014/296063
    The methanolic extracts of 13 accessions of purslane were analyzed for their total phenol content (TPC), total flavonoid contents (TFC), and total carotenoid contents (TCC) and antioxidant activity of extracts was screened using FRAP assay and DPPH radical scavenging methods. The TPC, TFC, and TCC ranged from 0.96 ± 0.04 to 9.12 ± 0.29 mg GAE/g DW, 0.13 ± 0.04 to 1.44 ± 0.08 mg RE/g DW, and 0.52 ± 0.06 to 5.64 ± 0.09 mg (β-carotene equivalent) BCE/g DW, respectively. The DPPH scavenging (IC50) activity varied between 2.52 ± 0.03 mg/mL and 3.29 ± 0.01 mg/mL and FRAP ranged from 7.39 ± 0.08 to 104.2 ± 6.34  μmol TE/g DW. Among all the measured micro- and macrominerals K content was the highest followed by N, Na, Ca, Mg, P, Fe, Zn, and Mn. The overall findings proved that ornamental purslane was richer in antioxidant properties, whereas common purslane possesses more mineral contents than ornamental ones.
    Matched MeSH terms: Phenols/analysis
  2. Phytochemical quantification and HPLC analysis of Parkia speciosa pod extract
    Cheong NDH, Mohamed E, Haron N, Camalxaman SN, Abdullah A, Mohamad Yusof MI, et al.
    Med J Malaysia, 2024 Mar;79(Suppl 1):34-39.
    PMID: 38555883
    INTRODUCTION: Parkia speciosa Hassk., commonly known as bitter bean or twisted cluster bean, is a tropical leguminous plant species native to Southeast Asia. The plant's edible pods have been traditionally used in various cuisines, particularly in Malaysian, Thai, and Indonesian cooking. Apart from being used as a food ingredient, the pods of P. speciosa also have a range of potential applications in other fields, including medicine, agriculture, and industry. The pods are said to have several phytochemicals that hold great therapeutic values such as reducing inflammation, improving digestion, and lowering blood sugar levels. However, there is limited information on the specific phytochemical contents of the pods in the literature. Thus, the aim of this study is to quantify the total phenolic and flavonoid compounds and to determine the concentrations of four selected phytochemical compounds in the P. speciosa pod extract (PSPE).

    MATERIALS AND METHODS: Quantification of the total phenolic (TPC) and flavonoid contents (TFC) in PSPE were done via colourimetric methods; and the determination of the concentrations of four specific phytochemicals (gallic acid, caffeic acid, rutin, and quercetin) were done via High- Performance Liquid Chromatography (HPLC).

    RESULTS: Colourimetric determination of PSPE showed TPC and TFC values of 84.53±9.40 mg GAE/g and 11.96±4.51 mg QE/g, respectively. Additional analysis of the phytochemicals using HPLC revealed that there were 6.45±3.36 g/kg, 5.91±1.07 g/kg, 0.39±0.84 g/kg, and 0.19±0.47 g/kg of caffeic acid, gallic acid, rutin, and quercetin, respectively.

    CONCLUSION: The findings show that PSPE contains substantial amounts of caffeic acid, gallic acid, rutin, and quercetin, which may indicate its potential as antibacterial, anti-inflammatory, anti-lipid, and antiviral medicines.

    Matched MeSH terms: Phenols/analysis; Phenols/chemistry
  3. Antioxidant properties of phenolic Schiff bases: structure-activity relationship and mechanism of action
    Anouar el H, Raweh S, Bayach I, Taha M, Baharudin MS, Di Meo F, et al.
    J Comput Aided Mol Des, 2013 Nov;27(11):951-64.
    PMID: 24243063 DOI: 10.1007/s10822-013-9692-0
    Phenolic Schiff bases are known for their diverse biological activities and ability to scavenge free radicals. To elucidate (1) the structure-antioxidant activity relationship of a series of thirty synthetic derivatives of 2-methoxybezohydrazide phenolic Schiff bases and (2) to determine the major mechanism involved in free radical scavenging, we used density functional theory calculations (B3P86/6-31+(d,p)) within polarizable continuum model. The results showed the importance of the bond dissociation enthalpies (BDEs) related to the first and second (BDEd) hydrogen atom transfer (intrinsic parameters) for rationalizing the antioxidant activity. In addition to the number of OH groups, the presence of a bromine substituent plays an interesting role in modulating the antioxidant activity. Theoretical thermodynamic and kinetic studies demonstrated that the free radical scavenging by these Schiff bases mainly proceeds through proton-coupled electron transfer rather than sequential proton loss electron transfer, the latter mechanism being only feasible at relatively high pH.
    Matched MeSH terms: Phenols/pharmacology; Phenols/chemistry*
  4. Inducing antioxidant and antimicrobial activities in endophytic and endolichenic fungi by the use of light spectra treatments
    Gan PT, Lim YY, Ting ASY
    Arch Microbiol, 2023 Aug 11;205(9):304.
    PMID: 37566125 DOI: 10.1007/s00203-023-03649-y
    The influence of light exposure on antioxidant and antimicrobial activities of nine fungal isolates [Pseudopestalotiopsis theae (EF13), Fusarium solani (EF5), Xylaria venustula (PH22), Fusarium proliferatum (CCH), Colletotrichum boninese (PL9), Colletotrichum boninese (PL1), Colletotrichum boninese (OL2), Colletotrichum gloeosporioides (OL3) and Colletotrichum siamense (PL3)] were determined. The isolates were incubated in blue, red, green, yellow and white fluorescent light (12 h photoperiod of alternating light/dark). It was observed that green light induced higher total phenolic content (TPC) (2.96 ± 0.16 mg-30.71 ± 1.03 mg GAE/g) and ferric reducing antioxidant power (FRAP) in most isolates (4.82 ± 0.04-53.55 ± 4.33 mg GAE/g), whereas red light induced higher total flavonoid content (TFC) levels (1.14 ± 0.08-18.40 ± 1.12 mg QE/g). The crude extracts from most fungal cultures exposed to green and red lights were also notably more potent against the tested pathogens, as larger zones of inhibition (ZOI) (9.00 ± 1.00-38.30 ± 2.90 mm) and lower minimum inhibitory concentration (MIC) (0.0196-1.25 mg/mL) were achieved for antimicrobial effect. This study showed that light treatments are effective strategies in enhancing production of more potent antimicrobial compounds and valuable antioxidants from fungal isolates.
    Matched MeSH terms: Phenols
  5. Equilibrium isotherms, kinetics and thermodynamics studies of phenolic compounds adsorption on palm-tree fruit stones
    Ahmed MJ, Theydan SK
    Ecotoxicol Environ Saf, 2012 Oct;84:39-45.
    PMID: 22795888 DOI: 10.1016/j.ecoenv.2012.06.019
    Adsorption capacity of an agricultural waste, palm-tree fruit stones (date stones), for phenolic compounds such as phenol (Ph) and p-nitro phenol (PNPh) at different temperatures was investigated. The characteristics of such waste biomass were determined and found to have a surface area and iodine number of 495.71 m2/g and 475.88 mg/g, respectively. The effects of pH (2-12), adsorbent dose (0.6-0.8 g/L) and contact time (0-150 min) on the adsorptive removal process were studied. Maximum removal percentages of 89.95% and 92.11% were achieved for Ph and PNPh, respectively. Experimental equilibrium data for adsorption of both components were analyzed by the Langmuir, Freundlich and Tempkin isotherm models. The results show that the best fit was achieved with the Langmuir isotherm equation with maximum adsorption capacities of 132.37 and 161.44 mg/g for Ph and PNPh, respectively. The kinetic data were fitted to pseudo-first order, pseudo-second order and intraparticle diffusion models, and was found to follow closely the pseudo-second order model for both components. The calculated thermodynamic parameters, namely ΔG, ΔH, and ΔS showed that adsorption of Ph and PNPh was spontaneous and endothermic under examined conditions.
    Matched MeSH terms: Phenols/metabolism*
  6. Fulltext Nutritional Composition and Antioxidant Properties of Golden Lily and Chokanan Mango (Mangifera indica) Peels
    Jing Wen Kok, Tengku Rozaina Tengku Mohamad, Tengku Rozaina Tengku Mohamad
    UMT Journal of Undergraduate Research, 2020;2(3):35-44.
    MyJurnal
    Mango is one of the popular fruits in Malaysia and has been used in the jam, puree and drinks production. Production of food products using mango pulp has generated by-products such as peel and kernel. Disposal of these by-products will cause environmental pollution if not properly treated. Mango peel contains high nutritional composition and antioxidant properties and can be utilised as food ingredients. The objectives of this study are to determine the nutritional composition and antioxidant properties of the peels of two selected mango varieties, namely Golden Lily and Chokanan. Analysis of proximate composition, minerals, total phenolic compounds, carotenoids, and antioxidant activity (DPPH and ABTS) were carried out in this study. Results of the proximate analysis showed that the peels of both mango varieties were a good source of fibre, which were 14.45% for Golden Lily and 14.89% for Chokanan. The crude fat, crude protein, and total carbohydrate of Chokanan peel (2.62%, 4.67% and 57.74%, respectively) were higher than the Golden Lily peel (1.13%, 2.90% and 53.16%, respectively). Contrastingly, the moisture content of the Golden Lily peel (24.67%) was higher than the Chokanan peel (16.61%). Potassium was the main mineral found in both Golden Lily and Chokanan mango peels (8802.10 mg/kg and 8443.60 mg/kg, respectively). The total phenolic compounds in the peels of both mango varieties were not significantly different. The Chokanan peel contained a higher carotenoids content (35.26 µg/g) than the Golden Lily peel (15.03 µg/g). The ABTS value for Chokanan peel was higher (1406.00 μmol TE/g) than Golden Lily peel (1314.00 μmol TE/g). This study showed that Chokanan and Golden Lily mango peels have the potential to be utilised as ingredient in food products due to their high fibre content.
    Matched MeSH terms: Phenols
  7. Fulltext Potential uses of cocoa bean infested by Conopomorpha cramerella for polyphenol extraction
    Misnawi, Teguh, W.
    International Food Research Journal, 2008;15(1):27-34.
    MyJurnal
    Cocoa pod borer (Conopomorpha cramerella (Snellen)) is the main fatal pest that destroys cocoa plantations in South East Asia, mainly in Indonesia and Malaysia. Infested cocoa beans stick to each other, the pulp become hard and normal fermentation process to produce flavour precursors cannot be done. This research aimed to utilize the infested cocoa beans as a source of phenolic compounds. Extraction of phenolic compounds was carried out for three infestation levels regarded as low, medium and heavy. Parameters of study were bean size, shell content, fat content, total polyphenol and antioxidant activity. Results of the study showed that the increase in cocoa pod borer infestation significantly decreased cocoa bean size, fat content and total polyphenol; but shell content was increased. Antioxidant activity of the extracted polyphenol was not significantly affected by the infestation. The results clearly indicate that cocoa beans infested by cocoa pod borer can potentially to be used as a source of phenolic compounds for natural antioxidant uses.
    Matched MeSH terms: Phenols; Polyphenols
  8. Fulltext Comparative Evaluation of Different Extraction Techniques and Solvents for the Assay of Phytochemicals and Antioxidant Activity of Hashemi Rice Bran
    Ghasemzadeh A, Jaafar HZ, Juraimi AS, Tayebi-Meigooni A
    Molecules, 2015 Jun 11;20(6):10822-38.
    PMID: 26111171 DOI: 10.3390/molecules200610822
    Secondary metabolite contents (total phenolic, flavonoid, tocopherol, and tocotrienol) and antioxidant activities of Hashemi rice bran extracts obtained by ultrasound-assisted and traditional solvent (ethanol and 50:50 (v/v) ethanol-water) extraction techniques were compared. Phenolic and, flavonoid compounds were identified using ultra-high performance liquid chromatography and method validation was performed. Significant differences (p < 0.05) were observed among the different extraction techniques upon comparison of phytochemical contents and antioxidant activities. The extracts obtained using the ethanol-water (50:50 v/v) ultrasonic technique showed the highest amounts of total phenolics (288.40 mg/100 g dry material (DM)), total flavonoids (156.20 mg/100 g DM), and total tocotrienols (56.23 mg/100 g DM), and the highest antioxidant activity (84.21% 1,1-diphenyl-2-picrylhydrazyl (DPPH), 65.27% β-carotene-linoleic bleaching and 82.20% nitric oxide scavenging activity). Secondary metabolite contents and antioxidant activities of the rice bran extracts varied depending of the extraction method used, and according to their effectiveness, these were organized in a decreasing order as follows: ethanol-water (50:50 v/v) ultrasonic, ethanol-water (50:50 v/v) maceration, ethanol ultrasonic and ethanol maceration methods. Ferulic, gallic and chlorogenic acids were the most abundant phenolic compounds in rice bran extracts. The phytochemical constituents of Hashemi rice bran and its antioxidant properties provides insights into its potential application to promote health.
    Matched MeSH terms: Phenols
  9. Fulltext Alpha-Mangostin-Rich Extracts from Mangosteen Pericarp: Optimization of Green Extraction Protocol and Evaluation of Biological Activity
    Ghasemzadeh A, Jaafar HZE, Baghdadi A, Tayebi-Meigooni A
    Molecules, 2018 Jul 25;23(8).
    PMID: 30044450 DOI: 10.3390/molecules23081852
    Since α-mangostin in mangosteen fruits was reported to be the main compound able to provide natural antioxidants, the microwave-assisted extraction process to obtain high-quality α-mangostin from mangosteen pericarp (Garcinia mangostana L.) was optimized using a central composite design and response surface methodology. The parameters examined included extraction time, microwave power, and solvent percentage. The antioxidant and antimicrobial activity of optimized and non-optimized extracts was evaluated. Ethyl acetate as a green solvent exhibited the highest concentration of α-mangostin, followed by dichloromethane, ethanol, and water. The highest α-mangostin concentration in mangosteen pericarp of 121.01 mg/g dry matter (DM) was predicted at 3.16 min, 189.20 W, and 72.40% (v/v). The verification of experimental results under these optimized conditions showed that the α-mangostin value for the mangosteen pericarp was 120.68 mg/g DM. The predicted models were successfully developed to extract α-mangostin from the mangosteen pericarp. No significant differences were observed between the predicted and the experimental α-mangostin values, indicating that the developed models are accurate. The analysis of the extracts for secondary metabolites showed that the total phenolic content (TPC) and total flavonoid content (TFC) increased significantly in the optimized extracts (OE) compared to the non-optimized extracts (NOE). Additionally, trans-ferulic acid and catechin were abundant among the compounds identified. In addition, the optimized extract of mangosteen pericarp with its higher α-mangostin and secondary metabolite concentrations exhibited higher antioxidant activities with half maximal inhibitory concentration (IC50) values of 20.64 µg/mL compared to those of the NOE (28.50 µg/mL). The OE exhibited the highest antibacterial activity, particularly against Gram-positive bacteria. In this study, the microwave-assisted extraction process of α-mangostin from mangosteen pericarp was successfully optimized, indicating the accuracy of the models developed, which will be usable in a larger-scale extraction process.
    Matched MeSH terms: Phenols/chemistry
  10. A comparative study of storage stability in virgin coconut oil and extra virgin olive oil upon thermal treatment
    Henna Lu, F.S., Tan, P.P
    International Food Research Journal, 2009;16(3):343-354.
    MyJurnal
    This aim of this research is to investigate thermal stability of virgin coconut oil, (VCO) which was heated at 190°C upon 40 days storage as compared to extra virgin olive oil (EVOO). The changes in fatty acids composition through (GC), Fourier Transform Infrared (FTIR) spectra, iodine value (IV) and total phenolic content were determined throughout the period of study. Results from GC showed that there was significant changes (P
    Matched MeSH terms: Phenols
  11. Effect of steam blanching on lycopene and total phenolics in pink guava puree industry by-products
    Kong, K.W., Emmy, H.K.I., Azizah, O., Amin, I., Tan, C.P.
    International Food Research Journal, 2010;17(2):461-468.
    MyJurnal
    Lycopene and total phenolics of pink guava puree industry by-products (refiner, siever and decanter)
    were evaluated after steam blanching at selected temperatures and times. Lycopene content was in the order of decanter > siever > refiner (7.3, 6.3 and 1.5 mg/100 g, respectively), and the content of total phenolics was in the order of refiner > siever > decanter (4434.1, 2881.3 and 1529.3 mg GAE/100 g, respectively). Regression coefficients for temperatures (x1) and times (x2) from multiple linear regression models of siever and decanter showed significant (p
    Matched MeSH terms: Phenols
  12. Fulltext Impact of optimised cooking on the antioxidant activity in edible mushrooms
    Ng ZX, Tan WC
    J Food Sci Technol, 2017 Nov;54(12):4100-4111.
    PMID: 29085153 DOI: 10.1007/s13197-017-2885-0
    This study aimed to investigate the effect of four cooking methods with different durations on the in vitro antioxidant activities of five edible mushrooms, namely Agaricus bisporus, Flammulina velutipes, Lentinula edodes, Pleurotus ostreatus and Pleurotus eryngii. Among the raw samples, A. bisporus showed the highest total antioxidant activity (reducing power and radical scavenging), total flavonoid, ascorbic acid and water soluble phenolic contents. Short-duration steam cooking (3 min) increased the total flavonoid and ascorbic acid while prolonged pressure cooking (15 min) reduced the water soluble phenolic content in the mushrooms. The retention of antioxidant value in the mushrooms varied with the variety of mushroom after the cooking process. The cooking duration significantly affected the ascorbic acid in the mushrooms regardless of cooking method. To achieve the best antioxidant values, steam cooking was preferred for F. velutipes (1.5 min), P. ostreatus (4.5 min) and L. edodes (4.5 min) while microwave cooking for 1.5 min was a better choice for A. bisporus. Pressure cooked P. eryngii showed the best overall antioxidant value among the cooked samples. Optimised cooking method including pressure cooking could increase the antioxidant values in the edible mushrooms.
    Matched MeSH terms: Phenols
  13. Fulltext Standardised herbal extract of chlorogenic acid from leaves of Etlingera elatior (Zingiberaceae)
    Chan EW, Lim YY, Tan SP
    Pharmacognosy Res, 2011 Jul;3(3):178-84.
    PMID: 22022166 DOI: 10.4103/0974-8490.85003
    Chlorogenic acid (CGA) or 5-caffeoylquinic acid, was found to be the dominant phenolic compound in leaves of Etlingera elatior (Zingiberaceae). The CGA content of E. elatior leaves was significantly higher than flowers of Lonicera japonica (honeysuckle), the commercial source. In this study, a protocol to produce a standardised herbal CGA extract from leaves of E. elatior using column chromatography was developed.
    Matched MeSH terms: Phenols
  14. Evaluation of phytochemicals and antioxidant potential of a new polyherbal formulation TC-16: additive, synergistic or antagonistic?
    Yap VL, Tan LF, Rajagopal M, Wiart C, Selvaraja M, Leong MY, et al.
    BMC Complement Med Ther, 2023 Mar 28;23(1):93.
    PMID: 36978110 DOI: 10.1186/s12906-023-03921-0
    BACKGROUND: Scientific literature has demonstrated the association of free radicals in the aetiology of various chronic diseases. Hence, the identification of potent antioxidants remains a useful task. The combination of multiple herbs in polyherbal formulations (PHF) is often associated with greater therapeutic efficacy due to synergistic interactions. However, antagonism can occur in natural product mixtures and the resultant antioxidant potential might not always be the additive value of the antioxidant properties of each component. In this study, we aimed to evaluate the phytochemicals, antioxidative potential and interaction among the herbs in TC-16, a new PHF comprising Curcuma longa L., Zingiber officinale var. Bentong, Piper nigrum L., Citrofortunella microcarpa (Bunge) Wijnands and Apis dorsata honey.

    METHODS: TC-16 was screened for phytochemicals. Phenolic and flavonoid contents of TC-16 and its individual ingredients were determined, followed by assessment of antioxidant properties using in vitro assays including 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC) and β-carotene bleaching (BCB) assays. Interactions among the herbs were also investigated by calculating the difference in antioxidant activity and combination index.

    RESULTS: Alkaloids, flavonoids, terpenoids, saponins and glycosides were present in TC-16. TC-16 possessed the highest phenolic (46.14 ± 1.40 mg GAE/g) and flavonoid (132.69 ± 1.43 mg CE/g) contents following C. longa. Synergistic antioxidant activity among the herbs was evident in ORAC and BCB assays which uses mainly hydrogen atom transfer-based antioxidant mechanisms.

    CONCLUSIONS: TC-16 demonstrated roles in combating free radicals. In a PHF, synergistic interaction among the herbs is observed in some but not all mechanisms. Mechanisms showing synergistic interactions should be highlighted to maximise the beneficial property of the PHF.

    Matched MeSH terms: Phenols/chemistry
  15. Assessment of the potential allelopathic effects of pennisetum purpureum schumach. on the germination and growth of eleusine indica (l.) gaertn.
    Ismail B, Chuah T, Tan P
    Sains Malaysiana, 2015;44:269-274.
    Pennisetum purpureum Schumach. is a weed that is currently spreading rapidly to many parts of the world particularly tropical countries. The abundance of P. purpureum in Malaysia is presently a serious problem. A study was conducted to investigate and evaluate the potential allelopathic effects of P. purpureum on Eleusine indica L. Gaertn. using the aqueous leaf extract and plant debris incorporated into the soil. Low concentrations of the P. purpureum aqueous extract (2%) and debris incorporated into the soil (25/500 g) inhibited germination and seedling growth of the bioassay species (E. indica) by >80%. The responses of the bioassay species to the aqueous extract and debris-incorporated soil were concentration dependent. The aqueous extract had higher total phenolic content compared to that from the debris incorporated soil, indicating the presence of certain phytotoxic compounds in the leaf debris and leaf extracts.
    Matched MeSH terms: Phenols
  16. Fulltext Energy and nutritional composition of Tiger milk mushroom (Lignosus tigris Chon S. Tan) sclerotia and the antioxidant activity of its extracts
    Yap HY, Aziz AA, Fung SY, Ng ST, Tan CS, Tan NH
    Int J Med Sci, 2014;11(6):602-7.
    PMID: 24782649 DOI: 10.7150/ijms.8341
    The Lignosus is a genus of fungi that have useful medicinal properties. In Southeast Asia, three species of Lignosus (locally known collectively as Tiger milk mushrooms) have been reported including L. tigris, L. rhinocerotis, and L. cameronensis. All three have been used as important medicinal mushrooms by the natives of Peninsular Malaysia. In this work, the nutritional composition and antioxidant activities of the wild type and a cultivated strain of L. tigris sclerotial extracts were investigated. The sclerotia are rich in carbohydrates with moderate amount of protein and low fat content. Free radical scavenging activities of L. tigris sclerotial extracts correlate with their phenolic content, which ranges from 6.25 to 45.42 mg GAE/g extract. The FRAP values ranged from 0.002 to 0.041 mmol/min/g extract, while the DPPH(•), ABTS(•+), and superoxide anion (SOA) scavenging activities ranged from 0.18 to 2.53, 0.01 to 0.36, and -4.53 to 10.05 mmol Trolox equivalents/g extract, respectively. L. tigris cultivar shows good prospect to be developed into functional food due to its good nutritional value and potent SOA scavenging activity.
    Matched MeSH terms: Phenols/metabolism*; Phenols/chemistry
  17. Influence of sodium chloride treatment and polysaccharides as debittering agent on the physicochemical properties, antioxidant capacity and sensory characteristics of bitter gourd (Momordica charantia) juice
    Siti Rashima R, Maizura M, Kang WM, Fazilah A, Tan LX
    J Food Sci Technol, 2017 Jan;54(1):228-235.
    PMID: 28242920 DOI: 10.1007/s13197-016-2454-y
    The effects of sodium chloride (NaCl) (3.5%) solution and polysaccharides, such as carboxymethyl cellulose (CMC) (0.1, 0.3 and 0.5%) and gum arabic (5, 10 and 15%), on the physicochemical properties, antioxidant capacity and sensory characteristics of bitter gourd juice were investigated. An increase in the concentration of CMC and gum arabic significantly was observed to increase the lightness (L value) and the viscosity (mPas) of bitter gourd juice at all levels. Increased concentrations of gum arabic significantly increased the total soluble solids. The bitter gourd fruit treated with NaCl solution produced the highest lightness (L value) and scavenging activity of free radical 2,2-diphenyl-1-picrylhydrazyl of bitter gourd juice. Increased concentration of gum arabic up to 15% significantly increased the total phenolic content. The addition of 5% gum arabic effectively reduced the bitterness of the bitter gourd juice. Viscosity of the juice resulted in negative correlation for bitterness.
    Matched MeSH terms: Phenols
  18. Bioactive fractions containing methyl eugenol-derived sex pheromonal components in haemolymph of the male fruit fly Bactrocera dorsalis (Diptera: Tephritidae)
    Hee AK, Tan KH
    Bull. Entomol. Res., 2005 Dec;95(6):615-20.
    PMID: 16336709 DOI: 10.1079/BER2005392
    Sex pheromonal components of the tephritid fruit fly Bactrocera dorsalis (Hendel), 2-allyl-4,5-dimethoxyphenol and (E)-coniferyl alcohol, are biosynthesized from a highly potent male attractant, methyl eugenol, then sequestered and stored in the rectal gland prior to their release during courtship at dusk. These sex pheromonal components have been detected in the haemolymph and crop organ. Hence, attempts were made to separate and identify the haemolymph fractions which contained the sex pheromonal components. Identification of these bioactive fractions in methyl eugenol-fed male flies using gel filtration column chromatography and biodetection using live male flies showed two fractions as highly attractive to conspecific males. These fractions show a significant increase in protein absorbance in the elution profile of haemolymph from methyl eugenol-fed males compared with that from methyl eugenol-deprived males. The molecular mass of these bioactive fractions as determined by using gel filtration was in the peptide range of 3.3 to 5.5 kDa. Subsequent gas chromatography-mass spectrometry analyses further confirmed the presence of the pheromonal components in the bioactive fractions. The presence of these methyl eugenol-derived sex pheromonal components in specific haemolymph fractions suggests the involvement of a sex pheromone binding complex.
    Matched MeSH terms: Phenols/blood*
  19. Rectal gland of Bactrocera papayae: ultrastructure, anatomy, and sequestration of autofluorescent compounds upon methyl eugenol consumption by the male fruit fly
    Khoo CC, Tan KH
    Microsc Res Tech, 2005 Aug 1;67(5):219-26.
    PMID: 16170821 DOI: 10.1002/jemt.20199
    Sexually mature males of Bactrocera papayae are strongly attracted to and consume methyl eugenol (ME). Upon consumption, ME is biotransformed to two phenylpropanoids, 2-allyl-4,5-dimethoxyphenol (DMP) and (E)-coniferyl alcohol (CF), that are transported in the hemolymph, sequestered and stored in the rectal glands, and subsequently released as sex and aggregation pheromones during courtship. To date, very little work on the ultrastructure and anatomy of the rectal gland has been done, and the accumulation of phenylpropanoids in the rectal glands of males has not been observed visually. Our objectives are to describe the anatomy and fine structures of the rectal glands of males and females and to observe the accumulation of autofluorescent compounds in the rectal glands of males. The rectal glands of males and females have four rectal papillae with each papilla attached to a rectal pad. The rectal pads protrude from the rectal gland as the only surfaces of the gland that are not surrounded by muscles. The rectal papillae of ME-fed males had oil droplets and autofluorescent compounds that were absent from those of ME-deprived males. The autofluorescent compounds accumulated in the rectal sac, which is an evagination that is not found in rectal glands of females. The accumulation of these compounds increased with time and reached maximum at a day post-ME feeding and decreased thereafter. This trend is similar to the accumulation pattern of phenylpropanoids, CF and DMP in the rectal gland.
    Matched MeSH terms: Phenols/metabolism
  20. Male sex pheromonal components derived from methyl eugenol in the hemolymph of the fruit fly Bactrocera papayae
    Hee AK, Tan KH
    J Chem Ecol, 2004 Nov;30(11):2127-38.
    PMID: 15672660 DOI: 10.1023/B:JOEC.0000048778.02561.70
    Pharmacophagy of methyl eugenol (ME)--a highly potent male attractant, by Bactrocera papayae results in the hydroxylation of ME to sex pheromonal components, 2-ally-4,5-dimethoxyphenol (DMP) and (E)-coniferyl alcohol (CF). These compounds, which are also male attractants, are then sequestered and stored in the rectal gland prior to their release during courtship at dusk. Chemical analyses of the digestive tract (excluding the crop and rectal gland) showed the absence of the sex pheromonal components and their precursor, ME. However, B. papayae males were attracted to and fed on the ME-fed male hemolymph extracts but not on hemolymph extracts of ME-deprived males. After thin layer chromatography in a hexane:ethyl acetate solvent system, flies were attracted to and fed on the original point on the TLC plate where the hemolymph extract had been spotted, suggesting that the pheromone components were bound in polar complexes. Chemical analyses of the ME-fed male hemolymph and crop extracts revealed the presence of the sex pheromonal components. The presence of the ME-derived pheromonal components and the absence of ME in the hemolymph suggest that the hemolymph is involved in the transportation of sex pheromonal components from the crop to the rectal gland.
    Matched MeSH terms: Phenols/analysis; Phenols/chemistry
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