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Removal of pesticides from water and wastewater by different adsorbents: a review

Ahmad T, Rafatullah M, Ghazali A, Sulaiman O, Hashim R, Ahmad A

J Environ Sci Health C Environ Carcinog Ecotoxicol Rev, 2010 Oct;28(4):231-71.
PMID: 21069614 DOI: 10.1080/10590501.2010.525782

In this review article, the use of various low-cost adsorbents for the removal of pesticides from water and wastewater has been reviewed. Pesticides may appear as pollutants in water sources, having undesirable impacts to human health because of their toxicity, carcinogenicity, and mutagenicity or causing aesthetic problems such as taste and odors. These pesticides pollute the water stream and it can be removed very effectively using different low-cost adsorbents. It is evident from a literature survey of about 191 recently published papers that low-cost adsorbents have demonstrated outstanding removal capabilities for pesticides.
The use of date palm as a potential adsorbent for wastewater treatment: a review

Ahmad T, Danish M, Rafatullah M, Ghazali A, Sulaiman O, Hashim R, et al.

Environ Sci Pollut Res Int, 2012 Jun;19(5):1464-84.
PMID: 22207239 DOI: 10.1007/s11356-011-0709-8

BACKGROUND: In tropical countries, the palm tree is one of the most abundant and important trees. Date palm is a principal fruit grown in many regions of the world. It is abundant, locally available and effective material that could be used as an adsorbent for the removal of different pollutants from aqueous solution.
REVIEW: This article presents a review on the role of date palm as adsorbents in the removal of unwanted materials such as acid and basic dyes, heavy metals, and phenolic compounds. Many studies on adsorption properties of various low cost adsorbent, such as agricultural waste and activated carbons based on agricultural waste have been reported in recent years.
CONCLUSION: Studies have shown that date palm-based adsorbents are the most promising adsorbents for removing unwanted materials. No previous review is available where researchers can get an overview of the adsorption capacities of date palm-based adsorbent used for the adsorption of different pollutants. This review provides the recent literature demonstrating the usefulness of date palm biomass-based adsorbents in the adsorption of various pollutants.
Atomistic simulation studies of the α/β-glucoside and galactoside in anhydrous bilayers: effect of the anomeric and epimeric configurations

Ahmadi S, Manickam Achari V, Nguan H, Hashim R

J Mol Model, 2014 Mar;20(3):2165.
PMID: 24623320 DOI: 10.1007/s00894-014-2165-0

Fully atomistic molecular dynamics simulation studies of thermotropic bilayers were performed using a set of glycosides namely n-octyl-β-D-glucopyranoside (β-C8Glc), n-octyl-α-D-glucopyranoside (α-C8Glc), n-octyl-β-D-galactopyranoside (β-C8Gal), and n-octyl-α-D-galactopyranoside (α-C8Gal) to investigate the stereochemical relationship of the epimeric/anomeric quartet liner glycolipids with the same octyl chain group. The results showed that, the anomeric stereochemistry or the axial/equatorial orientation of C1-O1 (α/β) is an important factor controlling the area and d-spacing of glycolipid bilayer systems in the thermotropic phase. The head group tilt angle and the chain ordering properties are affected by the anomeric effect. In addition, the L(C) phase of β-C8Gal, is tilting less compared to those in the fluid L(α). The stereochemistry of the C4-epimeric (axial/equatorial) and anomeric (α/β) centers simultaneously influence the inter-molecular hydrogen bond. Thus, the trend in the values of the hydrogen bond for these glycosides is β-C8Gal > α-C8Glc > β-C8Glc > α-C8Gal. The four bilayer systems showed anomalous diffusion behavior with an observed trend for the diffusion coefficients; and this trend is β-C8Gal > β-C8Glc > α-C8Gal > α-C8Glc. The "bent" configuration of the α-anomer results in an increase of the hydrophobic area, chain vibration and chain disorganization. Since thermal energy is dispensed more entropically for the chain region, the overall molecular diffusion decreases.
Fulltext Lactobacillus acidophilus Antimicrobial Peptide Is Antagonistic to Aeromonas hydrophila

Akter N, Hashim R, Pham HQ, Choi SD, Lee DW, Shin JH, et al.

Front Microbiol, 2020;11:570851.
PMID: 33162953 DOI: 10.3389/fmicb.2020.570851

We identified an antimicrobial peptide (AMP) from Lactobacillus acidophilus that was antagonistic to Aeromonas hydrophila. In vitro studies such as well-diffusion and field trials revealed that the AMP was active against A. hydrophila. The field trials of AMP using A. hydrophila-infected Channa striatus with a mannone oligosaccharide (MOS) prebiotic, A. hydrophila antigens, A. hydrophila-infected fish serum, L. acidophilus, and Lactobacillus cell free-supernatant (LABS-CFS) on an indicator organism further revealed that the antimicrobial agent could protect C. striatus. Other than the AMP, none of the above were able to eliminate the infectious agent A. hydrophila, and were only able to delay the death rate for 3-4 days. Thus, we conclude that the AMP is antagonistic to A. hydrophila and may be used for treatment of A. hydrophila infections. Subsequent L. acidophilus whole-genome sequence analyses enabled an understanding of the (probable) gene arrangement and its location on the chromosome. This information may be useful in the generation of recombinant peptides to produce larger quantities for treatment.
Fulltext Pneumococcal serotype distribution and antibiotic susceptibility in Malaysia: A four-year study (2014-2017) on invasive paediatric isolates

Arushothy R, Ahmad N, Amran F, Hashim R, Samsudin N, Azih CRC

Int J Infect Dis, 2019 Mar;80:129-133.
PMID: 30572022 DOI: 10.1016/j.ijid.2018.12.009

OBJECTIVE: This study was performed to analyze the serotype distribution of Streptococcus pneumoniae causing invasive pneumococcal disease (IPD) in children aged 5 years and under in Malaysia and to assess the antimicrobial resistance.
METHODS: From 2014 to 2017, a total of 245 invasive S. pneumoniae isolates from children ≤5 years of age were received from hospitals all around Malaysia. All isolates were identified and subjected to serotyping and antimicrobial susceptibility testing.
RESULTS: Of the 245 isolates, 117 (48.0%) were from children aged <1year, 46 (19.05%) were from children aged 1-2 years, and 82 (33.0%) were from children aged 2-5 years. The most common serotypes were 14 (26.9%), 6B (19.6%), 19A (11.8%), 6A (10.6%), and 19F (6.9%) and vaccine coverage was 88.2% for PCV13, 64.1% for PCV10, and 63.3% for PCV7. Resistance to penicillin was 0.2% for non-meningitis cases and 22.2% for meningitis cases; erythromycin resistance was reported in 42.9%, co-trimoxazole in 35.9%, and tetracycline in 42.9%.
CONCLUSIONS: Serotypes 14, 6B, 19A, 6A, and 19F were the most common serotypes isolated from children with IPD in Malaysia during this pre-vaccination era. The lack of reports on the serotype distribution has limited action for the implementation of PCV in the national immunization programme (NIP). The information from this study may benefit future policies for the introduction of PCV in the Malaysian NIP and ultimately may reduce the morbidity and mortality among children in Malaysia.
Draft Genome Sequence of a Highly Resistant Streptococcus pneumoniae Serotype 15A Strain Isolated from Blood

Arushothy R, Ahmad N, Amran F, Hashim R, Samsuddin N, Che Azih CR

Genome Announc, 2018 Apr 19;6(16).
PMID: 29674530 DOI: 10.1128/genomeA.00167-18

After the introduction of the pneumococcal conjugate vaccine in Malaysia in recent years, the emergence of nonvaccine serotypes is of concern, particularly the antibiotic-resistant strains, with an increase specifically in serotype 15A. Here, we report the draft genome sequence of Streptococcus pneumoniae strain SS40_16, isolated from the blood sample of a 19-month-old female in 2016. SS40_16 is a multidrug-resistant strain with resistance to penicillin (MIC, ≥2 µg/ml), tetracycline, and trimethoprim-sulfamethoxazole. The strain belongs to serotype 15A and sequence type 1591 (ST1591).
Fulltext Multidrug-resistant Streptococcus pneumoniae causing invasive pneumococcal disease isolated from a paediatric patient

Arushothy R, Ramasamy H, Hashim R, Raj A S S, Amran F, Samsuddin N, et al.

Int J Infect Dis, 2020 Jan;90:219-222.
PMID: 31682962 DOI: 10.1016/j.ijid.2019.10.037

The emergence of non-vaccine multidrug-resistant Streptococcus pneumoniae serotypes is on rise. This study was performed to investigate a highly resistant serotype 15A S. pneumoniae isolated from the blood specimen of a 20-month-old patient who died of her infection. The SS40_16 isolate was resistant to erythromycin, co-trimoxazole, tetracycline, and chloramphenicol, as well as to penicillin, ceftriaxone, and cefotaxime (using meningitis cut-off points, Clinical and Laboratory Standards Institute). The isolate belonged to sequence type 1591 (ST1591) and was related to CC81 clonal complex, suggesting the possibility of horizontal gene transfer. Scanning electron microscopy comparison between resistant and sensitive pneumococcal isolates also indicated similar phenotypic characteristics that confer high resistance. The emergence of highly resistant non-vaccine pneumococci is of great concern to public health and in the clinical setting. Pneumococcal surveillance programs represent a crucial tool, not only for determining the impact of pneumococcal conjugate vaccines, but also for monitoring the selective pressure of serotype replacement with regard to the treatment of invasive pneumococcal disease.
Fulltext Assessing the national antibiotic surveillance data to identify burden for melioidosis in Malaysia

Arushothy R, Mohd Ali MR, Zambri HF, Muthu V, Hashim R, Chieng S, et al.

IJID Reg, 2024 Mar;10:94-99.
PMID: 38179416 DOI: 10.1016/j.ijregi.2023.11.014

OBJECTIVES: A leading cause of morbidity and mortality in Southeast Asia, the epidemiological data on melioidosis disease occurrence and mortality in Malaysia is not comprehensive. The aim of this study is to determine the burden of melioidosis and assess the National Surveillance for Antibiotic Resistance (NSAR) data as a potential tool melioidosis surveilance in Malaysia.
METHODS: We performed a retrospective analysis on the B. pseudomallei reposited data submitted to the NSAR network between January 2014 and December 2020. The data were screened for information on patient demographics and specimen types. Additional patient comorbidities and outcomes were drawn from parallel surveillance for bacteremic melioidosis.
RESULTS: The average annual incidence rate of melioidosis between 2014-2020 was 3.41 per 100,000 population and was significantly different between states (P <0.001). The highest incidence was observed in Pahang at 11.33 per 100,000 population. Individuals of Malay ethnicity, from the states of Pahang, Johor, Perak, and Negeri Sembilan aged 40-49, who were diabetic and working in agriculture-related sectors had a higher risk of succumbing to the infection.
CONCLUSION: Assessing the NSAR data proved to be a useful tool for the determination of the incidence and socio-demographic risk factors attributed to melioidosis in Malaysia.
The interplay of socio-psychological factors on school engagement among early adolescents

Awang-Hashim R, Kaur A, Noman M

J Adolesc, 2015 Dec;45:214-24.
PMID: 26513126 DOI: 10.1016/j.adolescence.2015.10.001

The study examined a conceptual model integrating existing knowledge on the linkages between life satisfaction, affect, purpose in life, and resilience with school engagement. This model posits direct relationships between all the social psychological variables and school engagement, and also indirect relationships between life satisfaction and school engagement as mediated by all the other variables in the study. The participants were 2381 students (1119 boys and 1262 girls) with average age of 15 years, from 40 national secondary schools in Malaysia. The findings supported the theoretical conceptualization. All variables were positively associated with school engagement. The strongest relationship was observed between overall life satisfaction and school engagement. The mediating model was partially supported. The study reiterates the adage that "it takes a village to raise a child". Implications for practice and future research are discussed in the context of engagement in school learning.
Reinforced lignin-phenol-glyoxal (LPG) wood adhesives from coconut husk

Aziz NA, Latip AFA, Peng LC, Latif NHA, Brosse N, Hashim R, et al.

Int J Biol Macromol, 2019 Dec 01;141:185-196.
PMID: 31479667 DOI: 10.1016/j.ijbiomac.2019.08.255

Lignin was extracted from coconut husk via alkaline pulping, either Kraft or soda. The isolated lignin samples were classified as hydroxy-benzaldehyde, vanillin, and syringaldehyde type according to Fourier-transform Infrared Spectroscopy, 1H and 13C Nuclear Magnetic Resonance (NMR) spectra. Soda lignin (SL) showed higher thermal stability and glass transition temperature (Tg) than Kraft lignin (KL) as proven by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. The soda-lignin-phenol-glyoxal (SLPG) resins with the optimum percentage of lignin substitution at 30% showed improved solid content and gel time in comparison to 30% of Kraft-lignin-phenol-glyoxal (KLPG) and phenol-glyoxal (PG) resin. The good mechanical properties in SLPG is due to the higher amount of molecular weight as well as higher phenolic and G-type unit in lignin that improve the properties of 30% SLPG adhesive. Moreover, the addition of layered double hydroxides (LDH) as reinforced filler up to 15%-30% SLPG adhesive blend shows a great performance (especially mechanical properties) as compared to 30% SLPG adhesive alone.
The effectiveness of pure Stichopus horrens extract toothpaste in reducing plaque-induced gingivitis following orthodontic bonding: A triple-blinded randomized controlled trial

Bakar NA, Jayah NI, Mohamed NR, Ali SM, Nasir SH, Hashim R, et al.

J World Fed Orthod, 2020 03;9(1):3-8.
PMID: 32672665 DOI: 10.1016/j.ejwf.2019.11.004

INTRODUCTION: Gingivitis is one of the commonest problems faced by patients with fixed appliances (FA) as there is close relation between the appliances to gingival sulcus. Stichopus horrens (SH) is a sea cucumber from the Indo-Pacific that has medical healing properties which have been traditionally used.
OBJECTIVE: To assess the effects of toothpaste containing aqueous SH extract on plaque-induced gingivitis following orthodontic bond-up and to identify the optimal concentration of SH.
METHODS: A single-centred; triple-blinded randomized controlled trial conducted in 40 patients with FA. Participants were randomly assigned to one of the four groups with toothpaste which has concentration of SH extract of 0%, 3%, 6% or 9%. The statistician, the participants and the researchers involved in data collection were kept blinded from the allocation. Gingival Index (GI) and Bleeding on Probing (BOP) for each group were taken at day 0,7,14 and 30.
RESULTS: 9% of SH-containing toothpaste (SHCT) showed most substantial result as there were significance difference of GI (P = 0.020) from Day 7 to 14 and from Day 0 to 14 (P = 0.020). There was also significance difference of BOP from Day 0 to 14 (P = 0.022) and from Day 0 to 30 (P = 0.027). Significant difference was seen in 3% of SHCT group with the decrease of GI (P = 0.004) from Day 1 to 14. There were no significant difference noted for 0% and 6% SHCT.
CONCLUSION: The 9% SHCT is the most effective concentration to reduce both the gingival inflammation (up to day 14) and bleeding on probing (up to day 30).
Survey of the exocrine system in Protanilla wallacei (Hymenoptera, Formicidae)

Billen J, Bauweleers E, Hashim R, Ito F

Arthropod Struct Dev, 2013 May;42(3):173-83.
PMID: 23333930 DOI: 10.1016/j.asd.2013.01.001

We studied the exocrine system of both workers and ergatoid queens of Protanilla wallacei using light, scanning and transmission electron microscopy. Our survey revealed the presence of 26 glands, of which 6 had never been found before in ants. Five of these represent novel discoveries for social insects in general. The overall novel discoveries comprise an epithelial stipes gland, a pharyngeal wall gland, a central petiole gland, a lateral postpetiole gland and a foot-sole gland in the hindleg pretarsi. The intramandibular epithelial gland was already reported in some bees previously, but is now for the first time also reported in ants. The exocrine system of workers and ergatoid queens is very similar, with only the spermathecal gland showing an obvious difference. This is in line with the limited anatomical as well as behavioural difference between both castes in Protanilla compared to the situation in Leptanilla.
Diversity and morphology of abdominal glands in workers of the ant genus Myopias (Formicidae, Ponerinae)

Billen J, Stroobants Z, Wenseleers T, Hashim R, Ito F

Arthropod Struct Dev, 2013 May;42(3):165-72.
PMID: 23333627 DOI: 10.1016/j.asd.2012.12.001

Histological examination of serial sections through the abdomen of workers of three species of Myopias ants revealed the presence of several exocrine glands. These include the common venom and Dufour glands as well as the pygidial gland, but also more specific sternal glands and glands associated with the sting base and the gonostyli. Two of these glands have not been reported previously among ants: one is the paired oblong plate gland, that occurs next to the oblong plate and may have a pheromonal function. The other novel gland is the paired sting shaft gland, that occurs at the dorsal side in the proximal region of the sting shaft. A remarkable characteristic of these Myopias ants is that all glands of class-3 show ducts with gradually widening internal diameter. Myopias emeryi shows a clearly more simple variety of abdominal glands than Myopias maligna and M. sp.1.
Ultrastructure of the mandibular gland of the ant Myrmoteras iriodum

Billen J, Hashim R, Ito F

Arthropod Struct Dev, 2016 May 1.
PMID: 27130260 DOI: 10.1016/j.asd.2016.04.003

The mandibular gland in workers of the formicine ant Myrmoteras iriodum differs from other ants both in its general morphology and ultrastructural organization. The secretory cells appear in a pseudo-epithelial arrangement that gives them a clear polarity. At their apical side, the cells are characterized by a large cup-like extension of the reservoir, from which a bulbous invagination connects to a branched end apparatus. At the basal side, the cells show a labyrinth of basal invaginations, while the lateral cell contacts show clear interdigitations. The cytoplasmic composition reveals the presence of numerous round or elongate inclusions that contain crystalline material. Microtubules are abundant, and locally fibrillar regions are found. The function of the mandibular gland in M. iriodum has not yet been documented, and should be studied using gland extracts and behavioural observations.
Born-Oppenheimer Molecular Dynamics Study on Proton Dynamics of Strong Hydrogen Bonds in Aspirin Crystals, with Emphasis on Differences between Two Crystal Forms

Brela MZ, Wójcik MJ, Witek ŁJ, Boczar M, Wrona E, Hashim R, et al.

J Phys Chem B, 2016 04 28;120(16):3854-62.
PMID: 27045959 DOI: 10.1021/acs.jpcb.6b01601

In this study, the proton dynamics of hydrogen bonds for two forms of crystalline aspirin was investigated by the Born-Oppenheimer molecular dynamics (BOMD) method. Analysis of the geometrical parameters of hydrogen bonds using BOMD reveals significant differences in hydrogen bonding between the two crystalline forms of aspirin, Form I and Form II. Analysis of the trajectory for Form I shows spontaneous proton transfer in cyclic dimers, which is absent in Form II. Quantization of the O-H stretching modes allows a detailed discussion on the strength of hydrogen-bonding interactions. The focal point of our study is examination of the hydrogen bond characteristics in the crystal structure and clarification of the influence of hydrogen bonding on the presence of the two crystalline forms of aspirin. In the BOMD method, thermal motions were taken into account. Solving the Schrödinger equation for the snapshots of 2D proton potentials, extracted from MD, gives the best agreement with IR spectra. The character of medium-strong hydrogen bonds in Form I of aspirin was compared with that of weaker hydrogen bonds in aspirin Form II. Two proton minima are present in the potential function for the hydrogen bonds in Form I. The band contours, calculated by using one- and two-dimensional O-H quantization, reflect the differences in the hydrogen bond strengths between the two crystalline forms of aspirin, as well as the strong hydrogen bonding in the cyclic dimers of Form I and the medium-strong hydrogen bonding in Form II.
Fulltext Infection of army ant pupae by two new parasitoid mites (Mesostigmata: Uropodina)

Brückner A, Klompen H, Bruce AI, Hashim R, von Beeren C

PeerJ, 2017;5:e3870.
PMID: 29038753 DOI: 10.7717/peerj.3870

A great variety of parasites and parasitoids exploit ant societies. Among them are the Mesostigmata mites, a particularly common and diverse group of ant-associated arthropods. While parasitism is ubiquitous in Mesostigmata, parasitoidism has only been described in the genus Macrodinychus. Yet information about the basic biology of most Macrodinychus species is lacking. Out of 24 formally described species, information about basic life-history traits is only available for three species. Here we formally describe two new Macrodinychus species, i.e. Macrodinychus hilpertae and Macrodinychus derbyensis. In both species, immature stages developed as ecto-parasitoids on ant pupae of the South-East Asian army ant Leptogenys distinguenda. By piercing the developing ant with their chelicera, the mites apparently suck ant hemolymph, ultimately killing host individuals. We compare infection rates among all studied Macrodinychus species and discuss possible host countermeasures against parasitoidism. The cryptic lifestyle of living inside ant nests has certainly hampered the scientific discovery of Macrodinychus mites and we expect that many more macrodinychid species await scientific discovery and description.
Fulltext A preliminary report on ants (Hymenoptera: Formicidae) recovered from forensic entomological studies conducted in different ecological habitats in Malaysia

Chen CD, Nazni WA, Lee HL, Hashim R, Abdullah NA, Ramli R, et al.

Trop Biomed, 2014 Jun;31(2):381-6.
PMID: 25134909 MyJurnal

This study reported the ant species that were recovered from monkey carcasses in three different ecological habitats in Malaysia. The study was conducted from 9 May - 10 October 2007, 6 May - 6 August 2008 and 26 May - 14 July 2009 in forested area (Gombak, Selangor), coastal area (Tanjong Sepat, Selangor) and highland area (Bukit Cincin, Pahang), respectively. Monkey carcass was used as a model for human decomposition in this study. A total of 4 replicates were used in each of the study sites. Ants were observed to prey on eggs, larvae, pupae and newly emerged flies. This study found that ant species could be found at all stages of decomposition, indicating that ants were not a significant indicator for faunal succession. However, different species of ants were obtained from monkey carcasses placed in different ecological habitats. Cardiocondyla sp. was only found on carcasses placed in the coastal area; while Pheidole longipes, Hypoponera sp. and Pachycondyla sp. were solely found on carcasses placed in the highland area. On the other hand, Pheidologeton diversus and Paratrechina longicornis were found in several ecological habitats. These data suggests that specific ant species can act as geographic indicators for different ecological habitats in forensic entomology cases in Malaysia.
Molecular dynamics simulation of monoalkyl glycoside micelles in aqueous solution: influence of carbohydrate headgroup stereochemistry

Chong TT, Hashim R, Bryce RA

J Phys Chem B, 2006 Mar 16;110(10):4978-84.
PMID: 16526739

Comparative molecular dynamics simulations of n-octyl-beta-D-galactopyranoside (beta-C8Gal) and n-octyl-beta-D-glucopyranoside (beta-C8Glc) micelles in aqueous solution have been performed to explore the influence of carbohydrate stereochemistry on glycolipid properties at the atomic level. In particular, we explore the hypothesis that differences in T(m) and T(c) for beta-C8Gal and beta-C8Glc in lyotropic systems arise from a more extensive hydrogen bonding network between beta-C8Gal headgroups relative to beta-C8Glc, due to the axial 4-OH group in beta-C8Gal. Good agreement of the 13 ns micelle-water simulations with available experimental information is found. The micelles exhibit a similar shape, size, and degree of exposed alkyl chain surface area. We find net inter- and intra-headgroup hydrogen bonding is also similar for beta-C8Gal and beta-C8Glc, although n-octyl-beta-D-galactopyranoside micelles do exhibit a slightly greater degree of inter- and intra-headgroup hydrogen bonding. However, the main distinction in the calculated microscopic behavior of beta-C8Glc and beta-C8Gal micelles lies in solvent interactions, where beta-d-glucosyl headgroups are considerably more solvated (mainly at the equatorial O4 oxygen). These results agree with preceding theoretical and experimental studies of monosaccharides in aqueous solution. A number of long water residence times are found for solvent surrounding both micelle types, the largest of which are associated with surface protrusions involving headgroup clusters. Our simulations, therefore, predict differences in hydrogen bonding for the two headgroup stereochemistries, including a small difference in inter-headgroup interactions, which may contribute to the higher T(m) and T(c) values of beta-C8Gal surfactants relative to beta-C8Glc in lyotropic systems.
Fulltext Bioprospecting medicinal plants for antioxidant components

Coulibaly AY, Hashim R, Sulaiman SF, Sulaiman O, Ang LZ, Ooi KL

Asian Pac J Trop Med, 2014 Sep;7S1:S553-9.
PMID: 25312183 DOI: 10.1016/S1995-7645(14)60289-3

OBJECTIVE: To evaluate antioxidant activities of seven medicinal plant species and their fractions, and to identify their phenolic compounds.
METHODS: Two extractions were processed and further fractionated by column chromatography to evaluate the concentration that inhibit 50% of 2,2'-azinobis (3-ethylbenzothiazoline-6-suslfonic acid, 1,1-diphenyl-2-picryl-hydrazyl radicals, and their ferric reducing antioxidant power. The identification of the fractions of phenolic compounds was done by ultra performance liquid chromatography.
RESULTS: The aqueous-acetone extracts of Feretia apodanthera and Ozoroa insignis exhibited the highest antioxidant potentials comparable to those of the standard quercetin. Their subsequently silica gel column fractionation showed three most active fractions from which the major constituents quercetin, myricetin, kampferol, rutin and isoquercetin were identified.
CONCLUSIONS: These plant species have potent antioxidant profiles and polyphenol compounds that may help to manage with radical related disease and aging.
Fulltext Scavenging of caffeine from aqueous medium through optimized H3PO4-activated Acacia mangium wood activated carbon: Statistical data of optimization

Danish M, Birnbach J, Mohamad Ibrahim MN, Hashim R

Data Brief, 2020 Feb;28:105045.
PMID: 31921950 DOI: 10.1016/j.dib.2019.105045

The optimization data presented here are part of the study planned to remove the caffeine from aqueous solution through the large surface area optimized H3PO4-activated Acacia mangium wood activated carbon (OAMW-AC). The maximum adsorption capacity of the OAMW-AC for caffeine adsorption was achieved (30.3 mg/g) through optimized independent variables such as, OAMW-AC dosage (3.0 g/L), initial caffeine concentration (100 mg/L), contact time (60 min), and solution pH (7.7). The adsorption capacity of OAMW-AC was optimized with the help of rotatable central composite design of response surface methodology. Under the stated optimized conditions for maximum adsorption capacity, the removal efficiency was calculated to be 93%. The statistical significance of the data set was tested through the analysis of variance (ANOVA) study. Data confirmed the statistical model for caffeine adsorption was significant. The regression coefficient (R2) of curve fitting through the quadratic model was found to be 0.9832, and the adjusted regression coefficient was observed to be 0.9675.

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