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HPLC-Based Qualitative and Quantitative Analyses of Alkaloids in Chewable Areca Products from Different Geographic Regions

Cao M, Liu Y, Yuan H, Qiu Y, Xie Q, Yi P, et al.

J AOAC Int, 2020 Sep 01;103(5):1400-1405.
PMID: 33241395 DOI: 10.1093/jaoacint/qsaa048

BACKGROUND: Chewable areca products are popular in Asian countries, including India, Pakistan, Malaysia, and China. The major alkaloids present in areca products are guvacine, arecaidine, guvacoline, and arecoline which cause carcinogenicity and addiction.
OBJECTIVE: The objective of this study was the quantitative analysis of the alkaloid content of areca chewable products from different countries and regions using HPLC-UV, as well as the benefit of their safety evaluation products.
METHOD: An HPLC-UV method was established for qualitative and quantitative analyses of 65 batches of areca chewable products from different countries and regions. Additionally, similarity evaluation of chromatographic fingerprints was applied for data analysis.
RESULTS: These results reveal a significant variation in the levels of areca alkaloids among tested products, specifically guvacoline (0.060-1.216 mg/g), arecoline (0.376-3.592 mg/g), guvacine (0.028-1.184 mg/g), and arecaidine (0.184-1.291 mg/g). There were significant differences in the alkaloid content of areca chewable products from different producing areas.
CONCLUSIONS: The method will be useful in the safety evaluation of different areca chewable products.
HIGHLIGHTS: The established HPLC-UV method can be adopted for safety evaluation of areca chewable products from different countries and regions due to its general applicability.

Matched MeSH terms: Nicotinic Acids
Nicotinic acid content of foods

Leong PC

Journal of the Malaya Branch of the British Medical Association, 1940;4:261-78.

Matched MeSH terms: Nicotinic Acids
Degradation of imazapic and imazapyr herbicides in the presence of optimized oil palm empty fruit bunch and rice husk biochars in soil

Yavari S, Sapari NB, Malakahmad A, Yavari S

J Hazard Mater, 2019 03 15;366:636-642.
PMID: 30579230 DOI: 10.1016/j.jhazmat.2018.12.022

Imidazolinones as a persistent and active herbicides group have potential risks to non-target organisms in the environment. Biochar is a carbon-rich sorbent used as an amendment to change soil properties and its microbial communities effective on pesticides degradation rate. The present study was the first to compare empty fruit bunch (EFB) of oil palm and rice husk (RH) biomasses as biochar feedstock for remediation of imidazolinones-contaminated soils. Degradations of imazapic, imazapyr, and a mixture of them (Onduty®) was investigated in the presence of the optimized biochars in the soil during a 70-days incubation. Based on the results, the polar herbicides were resistant to hydrolysis degradation. Photolysis rates of the herbicides reduced significantly in the presence of the biochars in the soil. EFB biochar had greater effects due to its chemical compositions and surface functional groups. Photo-degradation of imazapyr was more affected by biochars amendment. The imidazolinones bio-degradation, however, accelerated significantly with the presence of EFB and RH biochars in soil with the greater effects of RH biochar. It was concluded that the application of the optimized EFB and RH biochars as an innovative sustainable strategy has the potential to decrease the persistence of the imidazolinones and minimize their environmental hazards.

Matched MeSH terms: Nicotinic Acids/chemistry*
Adsorption-Desorption Behavior of Polar Imidazolinone Herbicides in Tropical Paddy Fields Soils

Yavari S, Sapari NB, Malakahmad A, Razali MAB, Gervais TS, Yavari S

Bull Environ Contam Toxicol, 2020 Jan;104(1):121-127.
PMID: 31807794 DOI: 10.1007/s00128-019-02759-y

Analysis of herbicides sorption behavior in soil is critical in predicting their fate and possible harmful side effects in the environment. Application of polar imidazolinone herbicides is growing in tropical agricultural fields. Imidazolinones have high leaching potential and are persistent. In this study, adsorption-desorption of imazapic and imazapyr herbicides were evaluated in different types of Malaysian agricultural soils. Effects of soil parameters were also investigated on the soils' sorption capacities. The adsorption data fitted best to Freundlich isotherm (R2 > 0.991). The herbicides adsorptions were physical and spontaneous processes as ΔG values were negative and below 40 kJ/mol. The adsorption correlated positively with clay content, total organic carbon (TOC) content, and cation exchange capacity (CEC). There were strong negative correlations between hysteresis index and these factors indicating their importance in imidazolinones immobilization and, thus, their pollution reduction in the environment.

Matched MeSH terms: Nicotinic Acids/analysis*
Tissue-specific and maturity-dependent distribution of pyridine alkaloids in Areca triandra

Wu J, Zhang H, Wang S, Yuan L, Grünhofer P, Schreiber L, et al.

J Plant Res, 2019 Jul;132(4):531-540.
PMID: 31127431 DOI: 10.1007/s10265-019-01115-9

Areca nuts (seeds of Areca catechu L.) are a traditional and popular masticatory in India, Bangladesh, Malaysia, certain parts of China, and some other countries. Four related pyridine alkaloids (arecoline, arecaidine, guvacoline, and guvacine) are considered being the main functional ingredients in areca nut. Until now, A. catechu is the only known species producing these alkaloids in the Arecaceae family. In the present study, we investigated alkaloid contents in 12 Arecaceae species and found that only Areca triandra Roxb. contained these pyridine alkaloids. We further analyzed in more detail tissue-specific and development-related distribution of these alkaloids in leaves, male and female flowers and fruits in different stages of maturity in A. triandra by ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry. Results revealed that the alkaloids were most abundant in young leaves, the pericarp of ripe fruits and the endosperm of unripe fruits in developmental stage 2. Abundance of the 4 different alkaloids in A. triandra fruits varied during maturation. Pericarps of ripe fruits had the highest arecaidine concentration (4.45 mg g-1) and the lowest guvacoline concentration (0.0175 mg g-1), whereas the endosperm of unripe fruits of developmental stage 2 contained the highest guvacoline concentration (3.39 mg g-1) and the lowest guvacine concentration (0.245 mg g-1). We conclude that A. triandra is useful in future as a further valuable source of Areca alkaloids.

Matched MeSH terms: Nicotinic Acids/metabolism
Fulltext Global MLST of Salmonella Typhi Revisited in Post-genomic Era: Genetic Conservation, Population Structure, and Comparative Genomics of Rare Sequence Types

Yap KP, Ho WS, Gan HM, Chai LC, Thong KL

Front Microbiol, 2016;7:270.
PMID: 26973639 DOI: 10.3389/fmicb.2016.00270

Typhoid fever, caused by Salmonella enterica serovar Typhi, remains an important public health burden in Southeast Asia and other endemic countries. Various genotyping methods have been applied to study the genetic variations of this human-restricted pathogen. Multilocus sequence typing (MLST) is one of the widely accepted methods, and recently, there is a growing interest in the re-application of MLST in the post-genomic era. In this study, we provide the global MLST distribution of S. Typhi utilizing both publicly available 1,826 S. Typhi genome sequences in addition to performing conventional MLST on S. Typhi strains isolated from various endemic regions spanning over a century. Our global MLST analysis confirms the predominance of two sequence types (ST1 and ST2) co-existing in the endemic regions. Interestingly, S. Typhi strains with ST8 are currently confined within the African continent. Comparative genomic analyses of ST8 and other rare STs with genomes of ST1/ST2 revealed unique mutations in important virulence genes such as flhB, sipC, and tviD that may explain the variations that differentiate between seemingly successful (widespread) and unsuccessful (poor dissemination) S. Typhi populations. Large scale whole-genome phylogeny demonstrated evidence of phylogeographical structuring and showed that ST8 may have diverged from the earlier ancestral population of ST1 and ST2, which later lost some of its fitness advantages, leading to poor worldwide dissemination. In response to the unprecedented increase in genomic data, this study demonstrates and highlights the utility of large-scale genome-based MLST as a quick and effective approach to narrow the scope of in-depth comparative genomic analysis and consequently provide new insights into the fine scale of pathogen evolution and population structure.

Matched MeSH terms: Nicotinic Acids
The potential use of oil palm frond mulch treated with imazethapyr for weed control in Malaysian coconut plantation

Masilaman D, Mazira Che Mat, Chuah TS

Sains Malaysiana, 2017;46:1171-1182.

ntroduction of new weed management strategy for coconut plantation in Malaysia is essential since the current weed control methods are less effective and highly herbicide dependent, thus leading to development of herbicide resistance in weeds as well as environmental and human health concerns. Thus, the present study aimed to evaluate the phytotoxic effects of oil palm frond mulch treated with imazethapyr at a reduced rate on weed emergence and growth. The results of glasshouse experiments have shown that imazethapyr at 12 g a.i. ha-1 in combination with oil palm residues of leaflet (OPL), rachis (OPR) or frond (OPF) at rates of 1.4-1.8 t ha-1 inhibited Eleusine indica emergence and growth by 90-100%, implying that imazethapyr is compatible with oil palm residue mulches. In the field experiment, hand weeding followed by OPF at 3.4 t ha-1 treated with imazethapyr at 24 g a.i. ha-1 have demonstrated excellent control of Mikania micrantha, Asystasia gangetica, Phyllanthus amarus, Panicum sp. and Echinochloa colona by reducing their total dry weight up to 95% at three months after treatment. The present results suggested that the integration of chemical, physical and mechanical methods can provide effective weed control in the coconut plantation for months.

Matched MeSH terms: Nicotinic Acids
Synthesis, spectral studies and biological evaluation of 2-aminonicotinic acid metal complexes

Nawaz M, Abbasi MW, Hisaindee S, Zaki MJ, Abbas HF, Mengting H, et al.

Spectrochim Acta A Mol Biomol Spectrosc, 2016 May 15;161:39-43.
PMID: 26945123 DOI: 10.1016/j.saa.2016.02.022

We synthesized 2-aminonicotinic acid (2-ANA) complexes with metals such as Co(II), Fe(III), Ni(II), Mn(II), Zn(II), Ag(I),Cr(III), Cd(II) and Cu(II) in aqueous media. The complexes were characterized and elucidated using FT-IR, UV-Vis, a fluorescence spectrophotometer and thermo gravimetric analysis (TGA). TGA data showed that the stoichiometry of complexes was 1:2 metal/ligand except for Ag(I) and Mn(II) where the ratio was 1:1. The metal complexes showed varied antibacterial, fungicidal and nematicidal activities. The silver and zinc complexes showed highest activity against Bacillus subtilis and Bacillus licheniformis respectively. Fusarium oxysporum was highly susceptible to nickel and copper complexes whereas Macrophomina phaseolina was completely inert to the complexes. The silver and cadmium complexes were effective against the root-knot nematode Meloidogyne javanica.

Matched MeSH terms: Nicotinic Acids
Immunohistochemical expression of Tazarotene-induced Gene 3 in oral squamous cell carcinoma

Venkataswamy P, Samudrala Venkatesiah S, Rao RS, Banavar SR, Patil S, Augustine D, et al.

J Oral Pathol Med, 2020 Dec 01.
PMID: 33259689 DOI: 10.1111/jop.13144

BACKGROUND: The prognosis of hyperproliferative skin lesions, such as psoriasis, basal cell carcinoma, and non-melanoma skin cancers, is significantly benefited from the levels of tazarotene-induced gene-1 (TIG3) expression and subsequent treatment with tazarotene. Such observations suggest that TIG3 could be used as a biomarker for apoptosis, differentiation, and proliferation. The current study aimed to evaluate the expression of TIG3 in normal oral mucosa (NOM) and oral squamous cell carcinoma (OSCC) compared with normal skin (NS) and skin squamous cell carcinoma (SSCC) using immunohistochemistry.
METHODS: Seventeen cases each of SSCC, OSCC, NOM, and NS were evaluated. Each section was immunohistochemically stained with a rabbit polyclonal TIG3 antibody. The entire procedure was blinded and evaluated by 5 observers. Statistical analysis was performed using the chi-square test.
RESULTS: There was a significant decrease in TIG3 protein expression in OSCC and SSCC compared with that in NOM and NS (P = 0.008). The progressive loss of expression was observed as the grade of both malignancies increased. However, there was no significant difference in the expression among the normal tissue groups and within SCC groups of similar grades.
CONCLUSION: The present study suggests that the loss of TIG3 is an important event in carcinogenesis. TIG3 acts as a regulator of keratinocyte proliferation and terminal differentiation. Therefore, TIG3 could be a potential biomarker to differentiate aggressive and non-aggressive neoplasms.

Matched MeSH terms: Nicotinic Acids
Fulltext Ser-653-Asn substitution in the acetohydroxyacid synthase gene confers resistance in weedy rice to imidazolinone herbicides in Malaysia

Ruzmi R, Ahmad-Hamdani MS, Mazlan N

PLoS One, 2020;15(9):e0227397.
PMID: 32925921 DOI: 10.1371/journal.pone.0227397

The continuous and sole dependence on imidazolinone (IMI) herbicides for weedy rice control has led to the evolution of herbicide resistance in weedy rice populations across various countries growing IMI herbicide-resistant rice (IMI-rice), including Malaysia. A comprehensive study was conducted to elucidate occurrence, level, and mechanisms endowing resistance to IMI herbicides in putative resistant (R) weedy rice populations collected from three local Malaysian IMI-rice fields. Seed bioassay and whole-plant dose-response experiments were conducted using commercial IMI herbicides. Based on the resistance index (RI) quantification in both experiments, the cross-resistance pattern of R and susceptible (S) weedy rice populations and control rice varieties (IMI-rice variety MR220CL2 and non-IMI-rice variety MR219) to imazapic and imazapyr was determined. A molecular investigation was carried out by comparing the acetohydroxyacid synthase (AHAS) gene sequences of the R and S populations and the MR220CL2 and MR219 varieties. The AHAS gene sequences of R weedy rice were identical to those of MR220CL2, exhibiting a Ser-653-Asn substitution, which was absent in MR219 and S plants. In vitro assays were conducted using analytical grade IMI herbicides of imazapic (99.3%) and imazapyr (99.6%) at seven different concentrations. The results demonstrated that the AHAS enzyme extracted from the R populations and MR220CL2 was less sensitive to IMI herbicides than that from S and MR219, further supporting that IMI herbicide resistance was conferred by target-site mutation. In conclusion, IMI resistance in the selected populations of Malaysian weedy rice could be attributed to a Ser-653-Asn mutation that reduced the sensitivity of the target site to IMI herbicides. To our knowledge, this study is the first to show the resistance mechanism in weedy rice from Malaysian rice fields.

Matched MeSH terms: Nicotinic Acids/pharmacology