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Chitosan nanocarriers containing essential oils as a green strategy to improve the functional properties of chitosan: A review

Yang Y, Aghbashlo M, Gupta VK, Amiri H, Pan J, Tabatabaei M, et al.

Int J Biol Macromol, 2023 May 01;236:123954.
PMID: 36898453 DOI: 10.1016/j.ijbiomac.2023.123954

Large amounts of agricultural waste, especially marine product waste, are produced annually. These wastes can be used to produce compounds with high-added value. Chitosan is one such valuable product that can be obtained from crustacean wastes. Various biological activities of chitosan and its derivatives, especially antimicrobial, antioxidant, and anticancer properties, have been confirmed by many studies. The unique characteristics of chitosan, especially chitosan nanocarriers, have led to the expansion of using chitosan in various sectors, especially in biomedical sciences and food industries. On the other hand, essential oils, known as volatile and aromatic compounds of plants, have attracted the attention of researchers in recent years. Like chitosan, essential oils have various biological activities, including antimicrobial, antioxidant, and anticancer. In recent years, one of the ways to improve the biological properties of chitosan is to use essential oils encapsulated in chitosan nanocarriers. Among the various biological activities of chitosan nanocarriers containing essential oils, most studies conducted in recent years have been in the field of antimicrobial activity. It was documented that the antimicrobial activity was increased by reducing the size of chitosan particles in the nanoscale. In addition, the antimicrobial activity was intensified when essential oils were in the structure of chitosan nanoparticles. Essential oils can increase the antimicrobial activity of chitosan nanoparticles with synergistic effects. Using essential oils in the structure of chitosan nanocarriers can also improve the other biological properties (antioxidant and anticancer activities) of chitosan and increase the application fields of chitosan. Of course, using essential oils in chitosan nanocarriers for commercial use requires more studies, including stability during storage and effectiveness in real environments. This review aims to overview recent studies on the biological effects of essential oils encapsulated in chitosan nanocarriers, with notes on their biological mechanisms.

Matched MeSH terms: Antioxidants/chemistry
Cholinesterase inhibitory triterpenoids from the bark of Garcinia hombroniana

Jamila N, Khairuddean M, Yeong KK, Osman H, Murugaiyah V

J Enzyme Inhib Med Chem, 2015 Feb;30(1):133-9.
PMID: 24666300 DOI: 10.3109/14756366.2014.895720

Context: Garcinia hombroniana Pierre, known as manggis hutan in Malaysia is a rich source of xanthones and benzophenones.

Matched MeSH terms: Antioxidants/chemistry*
Fulltext Co-Solvent Selection for Supercritical Fluid Extraction (SFE) of Phenolic Compounds from Labisia pumila

Radzali SA, Markom M, Saleh NM

Molecules, 2020 Dec 11;25(24).
PMID: 33322389 DOI: 10.3390/molecules25245859

A preliminary study was conducted to study the effects of different types and concentrations of co-solvents based on yield, composition and antioxidants capacity of extract prior to optimization studies of supercritical fluid extraction (SFE) of Labisia pumila (locally referred to as 'kacip fatimah'). The following co-solvents were studied prior to the optimization of supercritical carbon dioxide (SC-CO2) technique: ethanol, water, methanol, as well as aqueous solutions of ethanol-water and methanol-water (50% and 70% v/v). By using the selected co-solvents, identification of phenolic acids (gallic acid, methyl gallate and caffeic acid) was determined by using High-Performance Liquid Chromatography (HPLC). Then, the antioxidant capacity was evaluated by using three different assays: total phenolic content (TPC), ferric reducing/antioxidant power (FRAP) and free radical-scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). SC-CO2 with 70% ethanol-water co-solvent was superior in terms of a higher combination of phenolic compounds extracted and antioxidants capacity. Overall, SC-CO2 with co-solvent 70% ethanol-water technique was efficient in extracting phenolic compounds from L. pumila, and thus the usage of this solvent system should be considered for further optimization studies.

Matched MeSH terms: Antioxidants/chemistry*
Fulltext Coconut water vinegar ameliorates recovery of acetaminophen induced liver damage in mice

Mohamad NE, Yeap SK, Beh BK, Ky H, Lim KL, Ho WY, et al.

BMC Complement Altern Med, 2018 Jun 25;18(1):195.
PMID: 29940935 DOI: 10.1186/s12906-018-2199-4

BACKGROUND: Coconut water has been commonly consumed as a beverage for its multiple health benefits while vinegar has been used as common seasoning and a traditional Chinese medicine. The present study investigates the potential of coconut water vinegar in promoting recovery on acetaminophen induced liver damage.
METHODS: Mice were injected with 250 mg/kg body weight acetaminophen for 7 days and were treated with distilled water (untreated), Silybin (positive control) and coconut water vinegar (0.08 mL/kg and 2 mL/kg body weight). Level of oxidation stress and inflammation among treated and untreated mice were compared.
RESULTS: Untreated mice oral administrated with acetaminophen were observed with elevation of serum liver profiles, liver histological changes, high level of cytochrome P450 2E1, reduced level of liver antioxidant and increased level of inflammatory related markers indicating liver damage. On the other hand, acetaminophen challenged mice treated with 14 days of coconut water vinegar were recorded with reduction of serum liver profiles, improved liver histology, restored liver antioxidant, reduction of liver inflammation and decreased level of liver cytochrome P450 2E1 in dosage dependent level.
CONCLUSION: Coconut water vinegar has helped to attenuate acetaminophen-induced liver damage by restoring antioxidant activity and suppression of inflammation.

Matched MeSH terms: Antioxidants/chemistry
Coenzyme Q10-Loaded Fish Oil-Based Bigel System: Probing the Delivery Across Porcine Skin and Possible Interaction with Fish Oil Fatty Acids

Zulfakar MH, Chan LM, Rehman K, Wai LK, Heard CM

AAPS PharmSciTech, 2018 Apr;19(3):1116-1123.
PMID: 29181705 DOI: 10.1208/s12249-017-0923-x

Coenzyme Q10 (CoQ10) is a vitamin-like oil-soluble molecule that has anti-oxidant and anti-ageing effects. To determine the most optimal CoQ10 delivery vehicle, CoQ10 was solubilised in both water and fish oil, and formulated into hydrogel, oleogel and bigel. Permeability of CoQ10 from each formulation across porcine ear skin was then evaluated. Furthermore, the effects of the omega-3 fatty eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids from fish oil on skin permeation were investigated by means of nuclear magnetic resonance (NMR) and computerised molecular modelling docking experiments. The highest drug permeation was achieved with the bigel formulation that proved to be the most effective vehicle in delivering CoQ10 across the skin membrane due to a combination of its adhesive, viscous and lipophilic properties. Furthermore, the interactions between CoQ10 and fatty acids revealed by NMR and molecular modelling experiments likely accounted for skin permeability of CoQ10. NMR data showed dose-dependent changes in proton chemical shifts in EPA and DHA. Molecular modelling revealed complex formation and large binding energies between fatty acids and CoQ10. This study advances the knowledge about bigels as drug delivery vehicles and highlights the use of NMR and molecular docking studies for the prediction of the influence of drug-excipient relationships at the molecular level.

Matched MeSH terms: Antioxidants/chemistry
Colloidal astaxanthin: preparation, characterisation and bioavailability evaluation

Anarjan N, Tan CP, Nehdi IA, Ling TC

Food Chem, 2012 Dec 1;135(3):1303-9.
PMID: 22953858 DOI: 10.1016/j.foodchem.2012.05.091

Astaxanthin colloidal particles were produced using solvent-diffusion technique in the presence of different food grade surface active compounds, namely, Polysorbate 20 (PS20), sodium caseinate (SC), gum Arabic (GA) and the optimum combination of them (OPT). Particle size and surface charge characteristics, rheological behaviour, chemical stability, colour, in vitro cellular uptake, in vitro antioxidant activity and residual solvent concentration of prepared colloidal particles were evaluated. The results indicated that in most cases the mixture of surface active compounds lead to production of colloidal particles with more desirable physicochemical and biological properties, as compared to using them individually. The optimum combination of PS20, SC and GA could produce the astaxanthin colloidal particles with small particle size, polydispersity index (PDI), conductivity and higher zeta potential, mobility, cellular uptake, colour intensity and in vitro antioxidant activity. In addition, all prepared astaxanthin colloidal particles had significantly (p<0.05) higher cellular uptake than pure astaxanthin powder.

Matched MeSH terms: Antioxidants/chemistry*
Fulltext Colostrum supplementation protects against exercise-induced oxidative stress in skeletal muscle in mice

Appukutty M, Radhakrishnan AK, Ramasamy K, Ramasamy R, Abdul Majeed AB, Noor MI, et al.

BMC Res Notes, 2012;5:649.
PMID: 23173926 DOI: 10.1186/1756-0500-5-649

This study examined the effects of bovine colostrum on exercise -induced modulation of antioxidant parameters in skeletal muscle in mice. Adult male BALB/c mice were randomly divided into four groups (control, colostrum alone, exercise and exercise with colostrum) and each group had three subgroups (day 0, 21 and 42). Colostrum groups of mice were given a daily oral supplement of 50 mg/kg body weight of bovine colostrum and the exercise group of mice were made to exercise on the treadmill for 30 minutes per day. Total antioxidants, lipid hydroperoxides, xanthine oxidase and super oxide dismutase level was assayed from the homogenate of hind limb skeletal muscle.

Matched MeSH terms: Antioxidants/chemistry
Colour, phenolic content and antioxidant capacity of some fruits dehydrated by a combination of different methods

Chong CH, Law CL, Figiel A, Wojdyło A, Oziembłowski M

Food Chem, 2013 Dec 15;141(4):3889-96.
PMID: 23993562 DOI: 10.1016/j.foodchem.2013.06.042

The objective of this study was to improve product quality of dehydrated fruits (apple, pear, papaya, mango) using combined drying techniques. This involved investigation of bioactivity, colour, and sensory assessment on colour of the dried products as well as the retention of the bio-active ingredients. The attributes of quality were compared in regard to the quality of dehydrated samples obtained from continuous heat pump (HP) drying technique. It was found that for apple, pear and mango the total colour change (ΔE) of samples dried using continuous heat pump (HP) or heat pump vacuum-microwave (HP/VM) methods was lower than of samples dried by other combined methods. However, for papaya, the lowest colour change exhibited by samples dried using hot air-cold air (HHC) method and the highest colour change was found for heat pump (HP) dehydrated samples. Sensory evaluation revealed that dehydrated pear with higher total colour change (ΔE) is more desirable because of its golden yellow appearance. In most cases the highest phenol content was found from fruits dried by HP/VM method. Judging from the quality findings on two important areas namely colour and bioactivity, it was found that combined drying method consisted of HP pre-drying followed by VM finish drying gave the best results for most dehydrated fruits studied in this work as the fruits contain first group of polyphenol compounds, which preferably requires low temperature followed by rapid drying strategy.

Matched MeSH terms: Antioxidants/chemistry*
Combination of light and oxygen accelerates formation of covalent protein-polyphenol bonding during chill storage of meat added 4-methyl catechol

Zainudin MAM, Jongberg S, Lund MN

Food Chem, 2021 Jan 01;334:127611.
PMID: 32712493 DOI: 10.1016/j.foodchem.2020.127611

Plant polyphenols applied as natural antioxidant ingredients, are known to bind to cysteine residues on meat proteins. The aim of this study was to examine the effect of light exposure on the formation of cysteine-phenol adduct in meat added 4-methylcatechol (4MC), a model polyphenol, during storage through quantitative LC-MS/MS-based analysis. Cysteine-4-methylcatechol adduct (Cys-4MC) formation in meat added 1500 ppm 4-MC increased significantly (by 50%) when stored under light in oxygen at 4 °C for 7 days as compared to storage in the dark. This was reflected by a significant decrease in thiol concentrations in the same sample. Gel electrophoresis showed loss in myosin heavy chain (MHC), and a resulting increase in cross-linked MHC (CL-MHC) and larger protein polymers in samples added 4MC. Protein blots stained with nitroblue tetrazolium (NBT) showed intensive protein-polyphenol binding in the meat samples added 4MC, but no major differences between storage conditions.

Matched MeSH terms: Antioxidants/chemistry
Combination of phenolic profiles, pharmacological properties and in silico studies to provide new insights on Silene salsuginea from Turkey

Zengin G, Rodrigues MJ, Abdallah HH, Custodio L, Stefanucci A, Aumeeruddy MZ, et al.

Comput Biol Chem, 2018 Dec;77:178-186.
PMID: 30336375 DOI: 10.1016/j.compbiolchem.2018.10.005

The genus Silene is renowned in Turkey for its traditional use as food and medicine. Currently, there are 138 species of Silene in Turkey, amongst which have been several studies for possible pharmacological potential and application in food industry. However, there is currently a paucity of data on Silene salsuginea Hub.-Mor. This study endeavours to access its antioxidant, enzyme inhibitory, and anti-inflammatory properties. Besides, reversed-phase high-performance liquid chromatography-diode array detector (RP-HPLC-DAD) was used to detect phenolic compounds, and molecular docking was performed to provide new insights for tested enzymes and phenolics. High amounts of apigenin (534 μg/g extract), ferulic acid (452 μg/g extract), p-coumaric acid (408 μg/g extract), and quercetin (336 μg/g extract) were detected in the methanol extract while rutin (506 μg/g extract) was most abundant in the aqueous extract. As for their biological properties, the methanol extract exhibited the best antioxidant effect in the DPPH and CUPRAC assays, and also the highest inhibition against tyrosinase. The aqueous extract was the least active enzyme inhibitor but showed the highest antioxidant efficacy in the ABTS, FRAP, and metal chelating assays. At a concentration of 15.6 μg/mL, the methanol extract resulted in a moderate decrease (25.1%) of NO production in lipopolysaccharide-stimulated cells. Among the phenolic compounds, epicatechin, (+)-catechin, and kaempferol showed the highest binding affinity towards the studied enzymes in silico. It can be concluded that extracts of S. salsuginea are a potential source of functional food ingredients but need further analytical experiments to explore its complexity of chemical compounds and pharmacological properties as well as using in vivo toxicity models to establish its maximum tolerated dose.

Matched MeSH terms: Antioxidants/chemistry
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: Antioxidants/chemistry*
Fulltext Comparative effect of Piper betle, Chlorella vulgaris and tocotrienol-rich fraction on antioxidant enzymes activity in cellular ageing of human diploid fibroblasts

Makpol S, Yeoh TW, Ruslam FA, Arifin KT, Yusof YA

BMC Complement Altern Med, 2013;13:210.
PMID: 23948056 DOI: 10.1186/1472-6882-13-210

Human diploid fibroblasts (HDFs) undergo a limited number of cellular divisions in culture and progressively reach a state of irreversible growth arrest, a process termed cellular ageing. Even though beneficial effects of Piper betle, Chlorella vulgaris and tocotrienol-rich fraction (TRF) have been reported, ongoing studies in relation to ageing is of interest to determine possible protective effects that may reverse the effect of ageing. The aim of this study was to evaluate the effect of P. betle, C. vulgaris and TRF in preventing cellular ageing of HDFs by determining the activity of antioxidant enzymes viz.; catalase, superoxide dismutase (SOD) and glutathione peroxidase.

Matched MeSH terms: Antioxidants/chemistry
Comparative nutritional and mycochemical contents, biological activities and LC/MS screening of tuber from new recipe cultivation technique with wild type tuber of tiger's milk mushroom of species Lignosus rhinocerus

Jamil NAM, Rashid NMN, Hamid MHA, Rahmad N, Al-Obaidi JR

World J Microbiol Biotechnol, 2017 Dec 04;34(1):1.
PMID: 29204733 DOI: 10.1007/s11274-017-2385-4

Tiger's milk mushroom is known for its valuable medicinal properties, especially the tuber part. However, wild tuber is very hard to obtain as it grows underground. This study first aimed to cultivate tiger's milk mushroom tuber through a cultivation technique, and second to compare nutritional and mycochemical contents, antioxidant and cytotoxic activities and compound screening of the cultivated tuber with the wild tuber. Results showed an increase in carbohydrate content by 45.81% and protein content by 123.68% in the cultivated tuber while fat content reduced by 13.04%. Cultivated tuber also showed an increase of up to 64.21% for total flavonoid-like compounds and 62.51% of total β-D-glucan compared to the wild tuber. The antioxidant activity of cultivated tuber and wild tuber was 760 and 840 µg mL-1, respectively. The cytotoxic activity of boiled water extract of cultivated tuber against a human lung cancer cell line (A549) was 65.50 ± 2.12 µg mL-1 and against a human breast cancer cell line (MCF7) was 19.35 ± 0.11 µg mL-1. β-D-glucan extract from the purification of boiled water extract of cultivated tuber showed cytotoxic activity at 57.78 ± 2.29 µg mL-1 against A549 and 33.50 ± 1.41 µg mL-1 against MCF7. However, the β-glucan extract from wild tuber did not show a cytotoxic effect against either the A549 or MCF7 cell lines. Also, neither of the extracts from cultivated tuber and wild tuber showed an effect against a normal cell line (MRC5). Compound profiling through by liquid chromatography mass spectrometry (LC/MS) showed the appearance of new compounds in the cultivated tuber. In conclusion, our cultivated tuber of tiger's milk mushroom using a new recipe cultivation technique showed improved nutrient and bioactive compound contents, and antioxidant and cytotoxic activities compared to the wild tuber. Further investigations are required to obtain a better quality of cultivated tuber.

Matched MeSH terms: Antioxidants/chemistry
Comparative phytochemical composition, oleuropein quantification, antioxidant and cytotoxic properties of Olea europaea L. leaves

Anwar S, Saleem H, Khurshid U, Ansari SY, Alghamdi S, Al-Khulaidi AWA, et al.

Nat Prod Res, 2023 Mar;37(6):1023-1029.
PMID: 35815778 DOI: 10.1080/14786419.2022.2097230

In the present research, oleuropein (OLE) contents from two Saudi Arabian wild olive trees (Olea europaea L.) leaves (O1 and O2), were collected from two nearby geographical sites differing in altitudes, and were determined via UHPLC-MS analysis. Moreover, total bioactive contents, antioxidant, and cytotoxicity (against MCF-7 and MDA-MB-231 cells) potential were also evaluated. The sample (O2) was found to contain significantly (p

Matched MeSH terms: Antioxidants/chemistry
Comparative study of the antioxidant activities of some lipase-catalyzed alkyl dihydrocaffeates synthesized in ionic liquid

Gholivand S, Lasekan O, Tan CP, Abas F, Wei LS

Food Chem, 2017 Jun 01;224:365-371.
PMID: 28159281 DOI: 10.1016/j.foodchem.2016.12.075

The solubility limitations of phenolic acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of dihydrocaffeic acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester.

Matched MeSH terms: Antioxidants/chemistry*
Comparison of free amino acids, antioxidants, soluble phenolic acids, cytotoxicity and immunomodulation of fermented mung bean and soybean

Ali NM, Yeap SK, Yusof HM, Beh BK, Ho WY, Koh SP, et al.

J Sci Food Agric, 2016 Mar 30;96(5):1648-58.
PMID: 26009985 DOI: 10.1002/jsfa.7267

BACKGROUND: Mung bean and soybean have been individually reported previously to have antioxidant, cytotoxic and immunomodulatory effects, while fermentation is a well-known process to enhance the bioactive compounds that contribute to higher antioxidant, cytotoxic and immunomodulation effects. In this study, the free amino acids profile, soluble phenolic acids content, antioxidants, cytotoxic and immunomodulatory effects of fermented and non-fermented mung bean and soybean were compared.
RESULTS: Fermented mung bean was recorded to have the highest level of free amino acids, soluble phenolic acids (especially protocatechuic acid) and antioxidant activities among all the tested products. Both fermented mung bean and soybean possessed cytotoxicity activities against breast cancer MCF-7 cells by arresting the G0/G1 phase followed by apoptosis. Moreover, fermented mung bean and soybean also induced splenocyte proliferation and enhanced the levels of serum interleukin-2 and interferon-γ.
CONCLUSION: Augmented amounts of free amino acids and phenolic acids content after fermentation enhanced the antioxidants, cytotoxicity and immunomodulation effects of mung bean and soybean. More specifically, fermented mung bean showed the best effects among all the tested products. This study revealed the potential of fermented mung bean and soybean as functional foods for maintenance of good health.

Matched MeSH terms: Antioxidants/chemistry*
Fulltext Competing role of bioactive constituents in Moringa oleifera extract and conventional nutrition feed on the performance of Cobb 500 broilers

Karthivashan G, Arulselvan P, Alimon AR, Safinar Ismail I, Fakurazi S

Biomed Res Int, 2015;2015:970398.
PMID: 25793214 DOI: 10.1155/2015/970398

The influence of Moringa oleifera (MO) leaf extract as a dietary supplement on the growth performance and antioxidant parameters was evaluated on broiler meat and the compounds responsible for the corresponding antioxidant activity were identified. 0.5%, 1.0%, and 1.5% w/v of MO leaf aqueous extracts (MOLE) were prepared, and nutritional feed supplemented with 0%, 0.5%, 1.0%, and 1.5% w/w of MO leaf meal (MOLM) extracts were also prepared and analysed for their in vitro antioxidant potential. Furthermore, the treated broiler groups (control (T1) and treatment (T2, T3, and T4)) were evaluated for performance, meat quality, and antioxidant status. The results of this study revealed that, among the broilers fed MOLM, the broilers fed 0.5% w/w MOLM (T2) exhibited enhanced meat quality and antioxidant status (P < 0.05). However, the antioxidant activity of the MOLE is greater than that of the MOLM. The LC-MS/MS analysis of MOLM showed high expression of isoflavones and fatty acids from soy and corn source, which antagonistically inhibit the expression of the flavonoids/phenols in the MO leaves thereby masking its antioxidant effects. Thus, altering the soy and corn gradients in conventional nutrition feed with 0.5% w/w MO leaves supplement would provide an efficient and cost-effective feed supplement.

Matched MeSH terms: Antioxidants/chemistry
Complete NMR assignments of bioactive rotameric (3 → 8) biflavonoids from the bark of Garcinia hombroniana

Jamila N, Khairuddean M, Khan SN, Khan N

Magn Reson Chem, 2014 Jul;52(7):345-52.
PMID: 24700704 DOI: 10.1002/mrc.4071

The genus Garcinia is reported to possess antimicrobial, anti-inflammatory, anticancer, hepatoprotective and anti-HIV activities. Garcinia hombroniana in Malaysia is used to treat itching and as a protective medicine after child birth. This study was aimed to isolate the chemical constituents from the bark of G. hombroniana and explore their possible pharmacological potential. Ethyl acetate extract afforded one new (1) and six (2-7) known 3 → 8 rotameric biflavonoids. Their structures were elucidated by UV, IR and NMR (1D and 2D) spectroscopy together with electron ionization/ESI mass spectrometric techniques and were identified as (2R, 3S) volkensiflavone-7-O-rhamnopyranoside (1), volkensiflavone (2), 4″-O-methyl-volkensiflavone (3), volkensiflavone-7-O-glucopyranoside (4), morelloflavone (5), 3″-O-methyl-morelloflavone (6) and morelloflavone-7-O-glucopyranoside (7). The absolute configuration of compound 1 was assigned by circular dichroism spectroscopy as 2R, 3S. The coexistence of conformers of isolated biflavonoids in solution at 25 °C in different solvents was confirmed by variable temperature NMR studies. At room temperature (25 °C), compounds 1-7 exhibited duplicate NMR signals, while at elevated temperature (90 °C), a single set of signals was obtained. Compound 5 showed significant in vitro antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis-3-ethyl benzthiazoline-6-sulfonic acid radicals. The antibacterial studies showed that compounds 5 and 6 are the most active against Staphylococcus aureus, Bacillus subtilis and Escherichia coli. Compounds 3 and 6 also showed moderate antituberculosis activity against H38 Rv. Based on the research findings, G. hombroniana could be concluded as a rich source of flavanone-flavone (3 → 8) biflavonoids that exhibit rotameric behaviour at room temperature and display significant antioxidant and antibacterial activities.

Matched MeSH terms: Antioxidants/chemistry
Fulltext Composition and Bioactivity of Essential Oil from Citrus grandis (L.) Osbeck 'Mato Peiyu' Leaf

Tsai ML, Lin CD, Khoo KA, Wang MY, Kuan TK, Lin WC, et al.

Molecules, 2017 Dec 05;22(12).
PMID: 29206180 DOI: 10.3390/molecules22122154

'Mato Peiyu' pomelo (Citrus grandis (L.) Osbeck 'Mato Peiyu') leaves from pruning are currently an agricultural waste. The aim of this study was to isolate essential oils from these leaves through steam distillation (SD) and solvent-free microwave extraction (SFME) and to evaluate their applicability to skin care by analyzing their antimicrobial, antioxidant (diphenyl-1-picrylhydrazyl scavenging assay, β-carotene/linoleic acid assay, and nitric oxide scavenging assay), anti-inflammatory (5-lipoxygenase inhibition assay), and antityrosinase activities. The gas chromatography-mass spectrometry results indicated that the main components of 'Mato Peiyu' leaf essential oils were citronellal and citronellol, with a total percentage of 50.71% and 59.82% for SD and SFME, respectively. The highest bioactivity among all assays was obtained for 5-lipoxygenase inhibition, with an IC50 value of 0.034% (v/v). The MIC90 of the antimicrobial activity of essential oils against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans ranged from 0.086% to 0.121% (v/v). Citronellal and citronellol were the main contributors, accounting for at least 54.58% of the essential oil's bioactivity. This paper is the first to report the compositions and bioactivities of 'Mato Peiyu' leaf essential oil, and the results imply that the pomelo leaf essential oil may be applied in skin care.

Matched MeSH terms: Antioxidants/chemistry*
Fulltext Compositional analyses of white, brown and germinated forms of popular Malaysian rice to offer insight into the growing diet-related diseases

Abubakar B, Yakasai HM, Zawawi N, Ismail M

J Food Drug Anal, 2018 04;26(2):706-715.
PMID: 29567241 DOI: 10.1016/j.jfda.2017.06.010

Diet-related metabolic diseases, and especially obesity, are metabolic disorders with multifactorial aetiologies. Diet has been a cornerstone in both the aetiology and management of this metabolic disorders. Rice, a staple food for over half of the world's population, could be exploited as part of the solution to check this menace which has been skyrocketing in the last decade. The present study investigated nine forms of rice from three widely grown Malaysian rice cultivars for in vitro and in vivo (glycaemic index and load) properties that could translate clinically into a lower predisposition to diet-related diseases. The germinated brown forms of MRQ 74 and MR 84 rice cultivars had high amylose content percentages (25.7% and 25.0%), high relative percentage antioxidant scavenging abilities of 85.0% and 91.7%, relatively low glycaemic indices (67.6 and 64.3) and glycaemic load (32.3 and 30.1) values, and modest glucose uptake capabilities of 33.69% and 31.25%, respectively. The results show that all things being equal, rice cultivars that are germinated and high in amylose content when compared to their white and low amylose counterparts could translate into a lower predisposition to diet-related diseases from the dietary point of view in individuals who consume this cereal as a staple food.

Matched MeSH terms: Antioxidants/chemistry

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