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Production, structure and morphology of exopolysaccharides yielded by submerged fermentation of Antrodia cinnamomea

Chen L, Wang Z, Zhang B, Ge M, Ng H, Niu Y, et al.

Carbohydr Polym, 2019 Feb 01;205:271-278.
PMID: 30446105 DOI: 10.1016/j.carbpol.2018.10.070

Carbon and nitrogen sources in culture medium of Antrodia cinnamomea were optimized to eliminate the interference of exterior macromolecules on exopolysaccharide (EPS) yield by submerged fermentation. The results suggested that culture medium containing 50 g/L of glucose and 20 g/L of yeast extract as the optimal carbon and nitrogen sources could produce 1.03 g/L of exopolysaccharides. After purification, two heteropolysaccharides (AC-EPS1 and AC-EPS2) were obtained and characterized to provide the basic structure information. As the main component of the produced EPS, AC-EPS2 (accounting for 89.63%) was mainly composed of galactose (87.42%) with Mw (molecular weight) and R.M.S. (root-mean-square) radius of 1.18 × 105 g/mol and 25.3 nm, respectively. Furthermore, the spherical and flexible chain morphologies of EPS were observed in different solvents by TEM. The structural and morphological information of purified EPS were significant for further study on their structure-activity relationship and related applications.

Matched MeSH terms: Culture Media/chemistry; Polysaccharides/chemistry*; Antrodia/chemistry
L-Glutamine-assisted synthesis of ZnO oatmeal-like/silver composites as an electrochemical sensor for Pb2+ detection

Mahmoudian MR, Basirun WJ, Woi PM, Yousefi R, Alias Y

Anal Bioanal Chem, 2019 Jan;411(2):517-526.
PMID: 30498983 DOI: 10.1007/s00216-018-1476-x

We report a green synthesis of oatmeal ZnO/silver composites in the presence of L-glutamine as an electrochemical sensor for Pb2+ detection. The synthesis was performed via the direct reduction of Ag+ in the presence of L-glutamine in NaOH. X-ray diffraction indicated that the Ag+ was completely reduced to metallic Ag. The field emission scanning electron microscopy (FESEM) and energy dispersive X-ray results confirmed an oatmeal-like morphology of the ZnO with the presence of Ag. The FESEM images showed the effect of L-glutamine on the ZnO morphology. The EIS results confirmed a significant decrease in the charge transfer resistance of the modified glassy carbon electrode due to the presence of Ag. From the differential pulse voltammetry results, a linear working range for the concentration of Pb2+ between 5 and 6 nM with LOD of 0.078 nM (S/N = 3) was obtained. The sensitivity of the linear segment is 1.42 μA nM-1 cm-2. The presence of L-glutamine as the capping agent and stabilizer decreases the size of Ag nanoparticles and prevents the agglomeration of ZnO, respectively. Graphical abstract ᅟ.

Matched MeSH terms: Glutamine/chemistry*; Lead/chemistry*; Avena/chemistry*
Effect of Solution Properties and Operating Parameters on Needleless Electrospinning of Poly(Ethylene Oxide) Nanofibers Loaded with Bovine Serum Albumin

Ramakrishnan R, Gimbun J, Ramakrishnan P, Ranganathan B, Reddy SMM, Shanmugam G

Curr Drug Deliv, 2019;16(10):913-922.
PMID: 31663478 DOI: 10.2174/1567201816666191029122445

BACKGROUND: This paper presents the effect of solution properties and operating parameters of polyethylene oxide (PEO) based nanofiber using a wire electrode-based needleless electrospinning.
METHODS: The feed solution was prepared using a PEO dissolved in water or a water-ethanol mixture. The PEO solution is blended with Bovine Serum Albumin protein (BSA) as a model drug to study the effect of the electrospinning process on the stability of the loaded protein. The polymer solution properties such as viscosity, surface tension, and conductivity were controlled by adjusting the solvent and salt content. The morphology and fiber size distribution of the nanofiber was analyzed using scanning electron microscopy.
RESULTS: The results show that the issue of a beaded nanofiber can be eliminated either by increasing the solution viscosity or by the addition of salt and ethanol to the PEO-water system. The addition of salt and solvent produced a high frequency of smaller fiber diameter ranging from 100 to 150 nm. The encapsulation of BSA in PEO nanofiber was characterized by three different spectroscopy techniques (i.e. circular dichroism, Fourier transform infrared, and fluorescence) and the results showed the BSA is well encapsulated in the PEO matrix with no changes in the protein structure.
CONCLUSION: This work may serve as a useful guide for a drug delivery industry to process a nanofiber at a large and continuous scale with a blend of drugs in nanofiber using a wire electrode electrospinning.

Matched MeSH terms: Polyethylene Glycols/chemistry*; Serum Albumin, Bovine/chemistry*; Nanofibers/chemistry*
Absolute Configuration of Alkaloids from Uncaria longiflora through Experimental and Computational Approaches

Salim F, Yunus YM, Anouar EH, Awang K, Langat M, Cordell GA, et al.

J Nat Prod, 2019 11 22;82(11):2933-2940.
PMID: 31686505 DOI: 10.1021/acs.jnatprod.8b00380

The structure elucidation of three new alkaloids named isoformosaninol (1), formosaninol (2), and longiflorine (3), isolated from the leaves of Uncaria longiflora var. pteropoda (Miq.) Ridsdale, along with their biosynthetic pathways are discussed. Their absolute structures were determined through a combination of physical data interpretation and quantum chemical calculations using the time-dependent density functional theory (TDDFT) method.

Matched MeSH terms: Alkaloids/chemistry*; Plant Leaves/chemistry; Uncaria/chemistry*
Fulltext Improving Water Permeability of Hydrophilic PVDF Membrane Prepared via Blending with Organic and Inorganic Additives for Humic Acid Separation

Arahman N, Mulyati S, Fahrina A, Muchtar S, Yusuf M, Takagi R, et al.

Molecules, 2019 Nov 13;24(22).
PMID: 31766222 DOI: 10.3390/molecules24224099

The removal of impurities from water or wastewater by the membrane filtration process has become more reliable due to good hydraulic performance and high permeate quality. The filterability of the membrane can be improved by having a material with a specific pore structure and good hydrophilic properties. This work aims at preparing a polyvinylidene fluoride (PVDF) membrane incorporated with phospholipid in the form of a 2-methacryloyloxyethyl phosphorylcholine, polymeric additive in the form of polyvinylpyrrolidone, and its combination with inorganic nanosilica from a renewable source derived from bagasse. The resulting membrane morphologies were analyzed by using scanning electron microscopy. Furthermore, atomic force microscopy was performed to analyze the membrane surface roughness. The chemical compositions of the resulting membranes were identified using Fourier transform infrared. A lab-scale cross-flow filtration system module was used to evaluate the membrane's hydraulic and separation performance by the filtration of humic acid (HA) solution as the model contaminant. Results showed that the additives improved the membrane surface hydrophilicity. All modified membranes also showed up to five times higher water permeability than the pristine PVDF, thanks to the improved structure. Additionally, all membrane samples showed HA rejections of 75-90%.

Matched MeSH terms: Polyvinyls/chemistry*; Pyrrolidines/chemistry; Water/chemistry*
Synergistic effect of probe sonication and ionic liquid for extraction of phenolic acids from oak galls

Sukor NF, Jusoh R, Kamarudin NS, Abdul Halim NA, Sulaiman AZ, Abdullah SB

Ultrason Sonochem, 2020 Apr;62:104876.
PMID: 31796331 DOI: 10.1016/j.ultsonch.2019.104876

Phenolic acids of oak gall were extracted using ultrasonic-probe assisted extraction (UPAE) method in the presence of ionic liquid. It was compared with classical ultrasonic-bath assisted extraction (CUBAE) and conventional aqueous extraction (CAE) method, with and without the presence of ionic liquid. Remarkably, the UPAE method yielded two-fold higher extraction yield with the presence of ionic liquid, resulting 481.04 mg/g for gallic acids (GA) and 2287.90 mg/g for tannic acids (TA), while a decreased value of 130.36 mg/g for GA and 1556.26 mg/g for TA were resulted with the absence of ionic liquid. Intensification process resulted the highest yield of 497.34 mg/g and 2430.48 mg/g for GA and TA, respectively, extracted at temperature 50 °C with sonication intensity of 8.66 W/cm2 and 10% duty cycle, diluted in ionic liquid, 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [Bmim][Tf2N] at concentration of 0.10 M with sample-to-solvent ratio 1:10 for 8 h. Peleg's model successfully predicted the UPAE process confirming that extraction capacity is the controlling factor in extracting phenolic acids. Hence, it can be concluded that UPAE method and ionic liquid have synergistic effect as it effectively enhanced the extraction efficiency to increase the bioactive constituents yield.

Matched MeSH terms: Solvents/chemistry; Quercus/chemistry*; Ionic Liquids/chemistry*
Oxidative properties of Moringa oleifera kernel oil from different extraction methods during storage

Mat Yusoff M, Niranjan K, Mason OA, Gordon MH

J Sci Food Agric, 2020 Mar 15;100(4):1588-1597.
PMID: 31773733 DOI: 10.1002/jsfa.10167

BACKGROUND: Moringa oleifera (MO) kernel oil is categorized as a high-oleic oil that resembles olive oil. However, unlike olive trees, MO trees are largely present in most subtropical and tropical countries. In these countries, therefore, the benefits of oleic acid can be obtained at a cheaper price through the consumption of MO kernel oil. This study reports on the effect of different extraction methods on oxidative properties of MO kernel oil during storage for 140 days at 13, 25, and 37 °C.
RESULTS: All aqueous enzymatic extraction (AEE)-based methods generally resulted in oil with better oxidative properties and higher tocopherol retention than the use of solvent. Prior to AEE, boiling pre-treatment deactivated the hydrolytic enzymes and preserved the oil's quality. In contrast, high-pressure processing (HPP) pre-treatment accelerated hydrolytic reaction and resulted in an increase in free fatty acids after 140 days at all temperatures. No significant changes were detected in the oils' iodine values and fatty acid composition. The tocopherol content decreased significantly at both 13 and 25 °C after 60 days in the oil from SE method, and after 120 days in oils from AEE-based methods.
CONCLUSION: These findings are significant in highlighting the extraction methods resulting in crude MO kernel oil with greatest oxidative stability in the storage conditions tested. Subsequently, the suitable storage condition of the oil prior to refining can be determined. Further studies are recommended in determining the suitable refining processes and parameters for the MO kernel oil prior to application in variety food products. © 2019 Society of Chemical Industry.

Matched MeSH terms: Plant Oils/chemistry*; Seeds/chemistry; Moringa oleifera/chemistry*
Fulltext A Potent Antifungal Agent for Basal Stem Rot Disease Treatment in Oil Palms Based on Chitosan-Dazomet Nanoparticles

Maluin FN, Hussein MZ, Yusof NA, Fakurazi S, Idris AS, Hilmi NHZ, et al.

Int J Mol Sci, 2019 May 07;20(9).
PMID: 31067720 DOI: 10.3390/ijms20092247

The use of nanotechnology could play a significant role in the agriculture sector, especially in the preparation of new-generation agronanochemicals. Currently, the economically important plant of Malaysia, the oil palm, faces the threat of a devastating disease which is particularly caused by a pathogenic fungus, Ganoderma boninense. For the development of an effective antifungal agent, a series of chitosan nanoparticles loaded with a fumigant, dazomet, were prepared using various concentrations of sodium tripolyphosphate (TPP)-2.5, 5, 10, and 20 mg/mL, abbreviated as CDEN2.5, CDEN5, CDEN10, and CDEN20, respectively. The effect of TPP as a crosslinking agent on the resulting particle size of the synthesized nanoparticles was investigated using a particle size analyzer and high-resolution transmission electron microscopy (HRTEM). Both methods confirmed that increasing the TPP concentration resulted in smaller particles. In addition, in vitro fumigant release at pH 5.5 showed that the release of the fumigant from the nanoparticles was of a sustained manner, with a prolonged release time up to 24 h. Furthermore, the relationship between the chitosan-dazomet nanoparticles and the in vitro antifungal activity against G. boninense was also explored, where the nanoparticles of the smallest size, CDEN20, gave the highest antifungal efficacy with the lowest half maximum effective concentration (EC50) value of 13.7 ± 1.76 ppb. This indicates that the smaller-sized agronanoparticles were more effective as an antifungal agent. The size can be altered, which plays a crucial role in combatting the Ganoderma disease. The agronanoparticles have controlled release properties and high antifungal efficacy on G. boninense, thus making them a promising candidate to be applied in the field for Ganoderma treatment.

Matched MeSH terms: Antifungal Agents/chemistry*; Thiadiazines/chemistry*; Nanoparticles/chemistry*
Enantioseparation of Selected Imidazole Drugs Using Dual Cyclodextrin-Modified Micellar Electrokinetic Chromatography

Ibrahim WAW, Wahib SMA, Hermawan D, Sanagi MM

Methods Mol Biol, 2019;1985:407-416.
PMID: 31069749 DOI: 10.1007/978-1-4939-9438-0_24

Particular attention has been paid to capillary electrophoresis as versatile and environmentally friendly approach for enantioseparations of a wide spectrum of compounds. Cyclodextrin-modified micellar electrokinetic chromatography (CD-MEKC) is a method of choice to provide effective separation toward hydrophobic and uncharged stereoisomers. The chiral discrimination of the solutes relies upon the partitioning between a given CD in the aqueous phase and micelles formed from a surfactant. Synergistic combinations of chiral selectors, surfactant, and modifier contribute to successful enantioseparations of the enantiomers. In this chapter, an application of CD-MEKC for the enantioseparation of selected imidazole drugs employing a dual CDs system is described.

Matched MeSH terms: Cyclodextrins/chemistry*; Pharmaceutical Preparations/chemistry; Imidazoles/chemistry*
Current potential and challenges in the advances of liquid crystalline nanoparticles as drug delivery systems

Madheswaran T, Kandasamy M, Bose RJ, Karuppagounder V

Drug Discov Today, 2019 07;24(7):1405-1412.
PMID: 31102731 DOI: 10.1016/j.drudis.2019.05.004

Lyotropic nonlamellar liquid crystalline nanoparticles (NPs) (LCN), such as cubosomes and hexosomes, are useful tools for applications in drug delivery because of their unique structural properties. LCNs are highly versatile carriers that can be applied for use with topical, oral, and intravenous treatments. In recent years, significant research has focused on improving their preparation and characterization, including controlling drug release and enhancing the efficacy of loaded bioactive molecules. Nevertheless, the clinical translation of LCN-based carriers has been slow. In this review, we highlight recent advances and challenges in the development and application of LCN, providing examples of their topical, oral, and intravenous drug delivery applications, and discussing translational obstacles to LCN as a NP technology.

Matched MeSH terms: Drug Carriers/chemistry; Liquid Crystals/chemistry*; Nanoparticles/chemistry*
Structures of triterpenoids from the leaves of Lansium domesticum

Matsumoto T, Kitagawa T, Ohta T, Yoshida T, Imahori D, Teo S, et al.

J Nat Med, 2019 Sep;73(4):727-734.
PMID: 31104253 DOI: 10.1007/s11418-019-01319-2

From the methanolic extract of the leaves of Lansium domesticum, three new onoceranoid-type triterpenoids, lansium acids X-XII and a new cycloartane-type triterpene, lansium acid XIII, were isolated. The chemical structures of the isolated new compounds were elucidated on the basis of chemical/physicochemical evidence. For new onoceranoid-type triterpenoids, the absolute configurations were established by comparison of experimental and predicted electronic circular dichroism (ECD) data. The isolated onoceranoid-type triterpenoids showed antimutagenic effects in the Ames assay against 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1).

Matched MeSH terms: Plant Extracts/chemistry*; Triterpenes/chemistry*; Meliaceae/chemistry*
The indole-based subincanadine alkaloids and their biogenetic congeners

Kalshetti MG, Argade NP

Alkaloids Chem Biol, 2020;83:187-223.
PMID: 32098650 DOI: 10.1016/bs.alkal.2019.12.001

The tryptamine-derived polycyclic bridged bioactive indole alkaloids subincanadines A-G were isolated in 2002 by Ohsaki and coworkers from the bark of the Brazilian medicinal plant Aspidosperma subincanum. Kobayashi proposed that subincanadines D-F could be biosynthetically resulting from stemmadenine via two different pathways and, furthermore, that the subincanadines A-C could be biogenetically resulting from subincanadines D and E. Kam and coworkers, in their focused efforts, isolated five indole alkaloids from Malaysian Kopsia arborea species, namely valparicine, apparicine, arboridinine, arborisidine, and arbornamine in combination with subincanadine E. On the basis of structural features, it has been proposed and proved in some examples that subincanadine E is a biogenetic precursor of these five different bioactive indole alkaloids bearing complex structural architectures. All important information on isolation, characterization, bioactivity, probable biogenetic pathways, and more specifically racemic and enantioselective total synthesis of subincanadine alkaloids and their biogenetic congeners are summarized in the present chapter. Special importance is given to the total synthesis and the synthetic strategies intended therein, comprising a set of main reactions.

Matched MeSH terms: Plants, Medicinal/chemistry*; Indole Alkaloids/chemistry*; Apocynaceae/chemistry*
Comparison of Disintegrant-addition Methods on the Compounding of Orodispersible Tablets

Mahesparan VA, Bin Abd Razak FS, Ming LC, Uddin AH, Sarker MZI, Bin LK

Int J Pharm Compd, 2020 3 21;24(2):148-155.
PMID: 32196477

Orodispersible tablets disintegrate rapidly (within 3 minutes) in the oral cavity and release the medicament before swallowing. The mode of disintegrant addition might affect the properties of orodispersible tablets. The objective of this study was to formulate and evaluate orodispersible tablets by studying different modes of disintegration addition with varying concentrations of disintegrants. The wet granulation method was used to produce the orodispersible tablets. Two methods of disintegration addition were compared (i.e., intragranular, extragranular). Three disintegrants (i.e., cornstarch, sodium starch glycolate, crospovidone) were used at three levels (5%, 10%, and 15%) in the study. The formulations were tested for the powder flowability (angle of repose) and characterized physically (hardness, weight, thickness, friability, disintegration time). The mangosteen pericarp extract was used as a model active pharmaceutical ingredient to be incorporated into the optimum formulation. It was observed that the extragranular method produced granules with better flowability compared to that of the intragranular method. Crospovidone was found as the most efficient disintegrant among the three. The optimum formulation selected was one with the highest concentration of crospovidone (15%), which showed the fastest disintegration time. The mode of disintegrant addition into the orodispersible tablets formulation was found to show a marked difference in the disintegration, as well as other physical characteristics of the orodispersible tablets where the extragranular mode of addition showed better property, which caused the orodispersible tablets to disintegrate the fastest.

Matched MeSH terms: Chemistry, Pharmaceutical/methods; Tablets/chemistry*
Fulltext Kinetics Study of Microwave-Assisted Brine Extraction of Lipid from the Microalgae Nannochloropsis sp

Zghaibi N, Omar R, Kamal SMM, Biak DRA, Harun R

Molecules, 2020 Feb 12;25(4).
PMID: 32059440 DOI: 10.3390/molecules25040784

The kinetics of lipid extraction utilizing microwave-assisted extraction (MAE) from Nannochloropsis sp. microalgae were studied using a low cost and green solvent, namely brine (NaCl) solution. The kinetic modelling of the lipid extraction was performed to evaluate the mechanism of the lipid mass transfer using different extraction models, including Fick's Law, First and Second-order Rate Law and the Patricelli mathematical model. The Patricelli mathematical model described the kinetics of lipid extraction well, with the highest average values of determination coefficient (R2 ≥ 0.952) and the lowest average values of mean relative percentage deviation (MRPD ≤ 8.666%). The lipid analysis indicated a positive influence of the microwave temperature and time on the quantity and quality of extracted lipids. SEM analysis of spent microalgae clearly shows an increase in the distorted cell with increase microwave temperature and time, which could be directly correlated to the mechanism of the MAE-brine technique.

Matched MeSH terms: Lipids/chemistry*; Salts/chemistry*; Microalgae/chemistry*
Alginate graft copolymers and alginate-co-excipient physical mixture in oral drug delivery

Wong TW

J Pharm Pharmacol, 2011 Dec;63(12):1497-512.
PMID: 22060280 DOI: 10.1111/j.2042-7158.2011.01347.x

Use of alginate graft copolymers in oral drug delivery reduces dosage form manufacture complexity with reference to mixing or coating processes. It is deemed to give constant or approximately steady weight ratio of alginate to covalently attached co-excipient in copolymers, thereby leading to controllable matrix processing and drug release. This review describes various grafting approaches and their outcome on oral drug release behaviour of alginate graft copolymeric matrices. It examines drug release modulation mechanism of alginate graft copolymers against that of co-excipients in non-grafted formulations.

Matched MeSH terms: Alginates/chemistry*; Chemistry, Pharmaceutical; Excipients/chemistry*
Protective potential of cerium oxide nanoparticles in diabetes mellitus

Chai WF, Tang KS

J Trace Elem Med Biol, 2021 Jul;66:126742.
PMID: 33773280 DOI: 10.1016/j.jtemb.2021.126742

BACKGROUND: Diabetes mellitus (DM) is a non-communicable metabolic disease which is closely related to excessive oxidative stress after constant exposure to high plasma glucose. Although the current antidiabetic medications are effective in lowering blood glucose, these medications do not prevent or reverse the disease progression. Thus, there is a crucial need to explore new therapeutic interventions that could address this shortcoming. As cerium oxide nanoparticles (CONPs) possess antioxidant property, this agent may be used as a treatment option for the management of DM.
PURPOSE: This review aims to provide a critical evaluation of the pharmacological and antidiabetic effects of CONPs in cell and animal models. The roles of CONPs in attenuating DM complications are also presented in this report.
METHODS: We conducted a literature search in the PubMed database using the keywords "cerium oxide", "cerous oxide", "ceria", "nanoceria", and "diabetes" from inception to December 2020. The inclusion criteria were primary source articles that investigated the role of CONPs in DM and diabetic complications.
RESULTS: We identified 47 articles from the initial search. After the thorough screening, only 31 articles were included in this study. We found that CONPs can attenuate parameters that are related to DM and diabetic complications in various animals and cell culture models.
CONCLUSION: CONPs could potentially be used in the treatment of those with DM and complications caused by the disease.

Matched MeSH terms: Cerium/chemistry; Protective Agents/chemistry; Nanoparticles/chemistry*
Fulltext Botanical Origin Differentiation of Malaysian Stingless Bee Honey Produced by Heterotrigona itama and Geniotrigona thoracica Using Chemometrics

Ng WJ, Sit NW, Ooi PA, Ee KY, Lim TM

Molecules, 2021 Dec 16;26(24).
PMID: 34946710 DOI: 10.3390/molecules26247628

Stingless bee honey, specifically honeydew honey, is generally valued for its better health benefits than those of most blossom types. However, scientific studies about the differentiation of stingless bee honey based on honeydew and blossom origins are very limited. In this study, 13C NMR spectroscopy was employed to quantify the seven major sugar tautomers in stingless bee honey samples, and the major sugar compositions of both honeydew and blossom types were found not significantly different. However, several physicochemical properties of honeydew honey including moisture content, free acidity, electrical conductivity, ash content, acetic acid, diastase, hydrogen peroxide, and mineral elements levels were significantly higher; while total soluble solid, proline, and hydroxymethylfurfural were significantly lower than blossom honey. Greater antioxidant capacity in honeydew honey was proven with higher total phenolic compounds, ABTS, DPPH, superoxide radical scavenging activities, peroxyl radical inhibition, iron chelation, and ferric reducing power. Using principal component analysis (PCA), two clusters of stingless bee honey from the honeydew and blossom origin were observed. PCA also revealed that the differentiation between honeydew and blossom origin of stingless bee honey is possible with certain physicochemical and antioxidant parameters. The combination of NMR spectroscopy and chemometrics are suggested to be useful to determine the authenticity and botanical origin of stingless bee honey.

Matched MeSH terms: Antioxidants/chemistry*; Carbohydrates/chemistry*; Phenols/chemistry*
Fulltext Malaysian researchers bet big on home-grown Viagra

Cyranoski D

Nat Med, 2005 Sep;11(9):912.
PMID: 16145563 DOI: 10.1038/nm0905-912a
Matched MeSH terms: Aphrodisiacs/chemistry; Plant Extracts/chemistry; Eurycoma/chemistry*
Fulltext Variations in Antioxidant Capacity, Oxidative Stability, and Physicochemical Quality Parameters of Walnut (Juglans regia) Oil with Roasting and Accelerated Storage Conditions

Elouafy Y, El Idrissi ZL, El Yadini A, Harhar H, Alshahrani MM, Al Awadh AA, et al.

Molecules, 2022 Nov 09;27(22).
PMID: 36431794 DOI: 10.3390/molecules27227693

Walnut oil, like all vegetable oils, is chemically unstable because of the sensitivity of its unsaturated fatty acids to the oxidation phenomenon. This phenomenon is based on a succession of chemical reactions, under the influence of temperature or storage conditions, that always lead to a considerable change in the quality of the oil by promoting the oxidation of unsaturated fatty acids through the degradation of their C-C double bonds, leading to the formation of secondary oxidation products that reduce the nutritional values of the oil. This research examines the oxidative stability of roasted and unroasted cold-pressed walnut oils under accelerated storage conditions. The oxidative stability of both oils was evaluated using physicochemical parameters: chemical composition (fatty acids, phytosterols, and tocopherols), pigment content (chlorophyll and carotenoids), specific extinction coefficients (K232 and K270), and quality indicators (acid and peroxide value) as well as the evaluation of radical scavenging activity by the DPPH method. The changes in these parameters were evaluated within 60 days at 60 ± 2 °C. The results showed that the levels of total phytosterols, the parameters of the acid and peroxide value, K232 and K270, increased slightly for both oils as well as the total tocopherol content and the antioxidant activity affected by the roasting process. In contrast, the fatty acid profiles did not change considerably during the 60 days of our study. After two months of oil treatment at 60 °C, the studied oils still showed an excellent physicochemical profile, which allows us to conclude that these oils are stable and can withstand such conditions. This may be due to the considerable content of tocopherols (vitamin E), which acts as an antioxidant.

Matched MeSH terms: Antioxidants/chemistry; Fatty Acids/chemistry; Plant Oils/chemistry
Fulltext Green photosensitisers for the degradation of selected pesticides of high risk in most susceptible food: A safer approach

Baig A, Zubair M, Sumrra SH, Rashid U, Zafar MN, Ahmad F, et al.

PLoS One, 2021;16(10):e0258864.
PMID: 34710164 DOI: 10.1371/journal.pone.0258864

Pesticides are the leading defence against pests, but their unsafe use reciprocates the pesticide residues in highly susceptible food and is becoming a serious risk for human health. In this study, mint extract and riboflavin were tested as photosensitisers in combination with light irradiation of different frequencies, employed for various time intervals to improve the photo-degradation of deltamethrin (DM) and lambda cyhalothrin (λ-CHT) in cauliflower. Different source of light was studied, either in ultraviolet range (UV-C, 254 nm or UV-A, 320-380 nm) or sunlight simulator (> 380-800 nm). The degradation of the pesticides varied depending on the type of photosensitiser and light source. Photo-degradation of the DM and λ-CHT was enhanced by applying the mint extracts and riboflavin and a more significant degradation was achieved with UV-C than with either UV-A or sunlight, reaching a maximum decrement of the concentration by 67-76%. The light treatments did not significantly affect the in-vitro antioxidant activity of the natural antioxidants in cauliflower. A calculated dietary risk assessment revealed that obvious dietary health hazards of DM and λ-CHT pesticides when sprayed on cauliflower for pest control. The use of green chemical photosensitisers (mint extract and riboflavin) in combination with UV light irradiation represents a novel, sustainable, and safe approach to pesticide reduction in produce.

Matched MeSH terms: Nitriles/chemistry*; Pesticides/chemistry*; Pyrethrins/chemistry*

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