Publications by authors named "Uthaiwan Suttisansanee"

27 Publications

  • Page 1 of 1

Synergistic Antibacterial and Anti-inflammatory Activities of Ethanolic Extract against Major Bacterial Mastitis Pathogens.

Antibiotics (Basel) 2022 Apr 12;11(4). Epub 2022 Apr 12.

Department of Pre-Clinical and Applied Animal Science, Faculty of Veterinary Science, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Mastitis is the most prevalent global illness affecting dairy cows. This bacterial infection damages and inflames the udder tissues. Several plant extracts have demonstrated synergistic antibacterial activities with standard drugs in mastitis treatment. Scant information exists on L. This study evaluated the antibacterial activity of extract and its interaction with antibacterial drugs against common mastitis pathogens including , coagulase-negative Staphylococci (CNS), , and . Anti-inflammatory activities in LPS-stimulated RAW264.7 macrophage cells were also studied. The extract exhibited antibacterial activities against , CNS, and with minimum inhibitory concentration (MIC) ranging from 3.9 to 31.2 µg/mL and minimum bactericidal concentration (MBC) ranging from 15.6 to 500 µg/mL. Combinations of with penicillin or amoxicillin-clavulanic acid showed synergistic effects against all tested strains but an additive effect with cefazolin and gentamicin. Pretreatment of the extract significantly decreased the expression of inflammatory molecules (IL-6, TNF-α, IL-1β, iNOS, COX-2, and PGE2) generated by LPS in macrophages. Results suggested effectiveness against various Gram-positive mastitis bacteria, with the potential to reduce antibacterial doses and combat inflammation.
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http://dx.doi.org/10.3390/antibiotics11040510DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9029753PMC
April 2022

Road to The Red Carpet of Edible Crickets through Integration into the Human Food Chain with Biofunctions and Sustainability: A Review.

Int J Mol Sci 2022 Feb 4;23(3). Epub 2022 Feb 4.

Food and Nutrition Academic and Research Cluster, Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

The Food and Agriculture Organization of the United Nations (FAO) estimates that more than 500 million people, especially in Asia and Africa, are suffering from malnutrition. Recently, livestock farming has increased to supply high-quality protein, with consequent impact on the global environment. Alternative food sources with high nutritive values that can substitute livestock demands are urgently required. Recently, edible crickets have been promoted by the FAO to ameliorate the food crisis. In this review, the distribution, nutritive values, health-promoting properties (antioxidant, anti-inflammatory, anti-diabetic and anti-obesity), safety, allergenicity as well as the potential hazards and risks for human consumption are summarized. Cricket farming may help to realize the United Nations sustainable development goal No. 2 Zero Hunger. The sustainability of cricket farming is also discussed in comparison with other livestock. The findings imply that edible crickets are safe for daily intake as a healthy alternative diet due to their high protein content and health-promoting properties. Appropriate use of edible crickets in the food and nutraceutical industries represents a global business potential. However, people who are allergic to shellfish should pay attention on cricket allergy. Thus, the objective of this review was to present in-depth and up-to-date information on edible crickets to advocate and enhance public perception of cricket-based food.
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http://dx.doi.org/10.3390/ijms23031801DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8836810PMC
February 2022

Impact of Drying Processes on Phenolics and In Vitro Health-Related Activities of Indigenous Plants in Thailand.

Plants (Basel) 2022 Jan 22;11(3). Epub 2022 Jan 22.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Thailand has vast areas of tropical forests with many indigenous plants, but limited information is available on their phytochemical profile and in vitro inhibitions of enzymatic and nonenzymatic reactions. This study investigated phenolic profiles using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), antioxidant activities, and in vitro inhibitory activities of 10 indigenous plants on key enzymes related to obesity (lipase), diabetes (α-amylase and α-glucosidase), and Alzheimer's disease (cholinesterases and β-secretase). The nonenzymatic anti-glycation reaction was also investigated. The 10 indigenous plants were (L.) Benth, (Burm.) Roscoe, Roxb., (Retz.) Swartz, Wall., Kurz., , L., Roxb, and J. Mood & T. Theleide. Preparations were made by either freeze-drying or oven-drying processes. Results suggested that the drying processes had a minor impact on in vitro inhibitions of enzymatic and nonenzymatic reactions (<4-fold difference). was the most potent antioxidant provider with high anti-glycation activity (>80% inhibition using the extract concentration of ≤6 mg/mL), while effectively inhibited β-secretase activity (>80% inhibition using the extract concentration of 10 mg/mL). exhibited the highest inhibitory activities against lipase (47-51% inhibition using the extract concentration of 1 mg/mL) and cholinesterases (>60% inhibition using the extract concentration of 2 mg/mL), while dominantly provided α-amylase and α-glucosidase inhibitors (>80% inhibition using the extract concentration of ≤2 mg/mL). Information obtained from this research may support usage of the oven-drying method due to its lower cost and easier preparation step for these studied plant species and plant parts. Furthermore, the information on in vitro inhibitions of enzymatic and nonenzymatic reactions could be used as fundamental knowledge for further investigations into other biological activities such as cell culture or in vivo experiments of these health-beneficial plants.
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http://dx.doi.org/10.3390/plants11030294DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8838347PMC
January 2022

Diplazium esculentum (Retz.) Sw. reduces BACE-1 activities and amyloid peptides accumulation in Drosophila models of Alzheimer's disease.

Sci Rep 2021 12 10;11(1):23796. Epub 2021 Dec 10.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, 73170, Nakhon Pathom, Thailand.

Alzheimer's disease (AD), one type of dementia, is a complex disease affecting people globally with limited drug treatment. Thus, natural products are currently of interest as promising candidates because of their cost-effectiveness and multi-target abilities. Diplazium esculentum (Retz.) Sw., an edible fern, inhibited acetylcholinesterase in vitro, inferring that it might be a promising candidate for AD treatment by supporting cholinergic neurons. However, evidence demonstrating anti-AD properties of this edible plant via inhibiting of neurotoxic peptides production, amyloid beta (Aβ), both in vitro and in vivo is lacking. Thus, the anti-AD properties of D. esculentum extract both in vitro and in Drosophila models of Aβ-mediated toxicity were elucidated. Findings showed that an ethanolic extract exhibited high phenolics and flavonoids, contributing to antioxidant and inhibitory activities against AD-related enzymes. Notably, the extract acted as a BACE-1 blocker and reduced amyloid beta 42 (Aβ42) peptides in Drosophila models, resulting in improved locomotor behaviors. Information gained from this study suggested that D. esculentum showed potential for AD amelioration and prevention. Further investigations in vertebrates or humans are required to determine the effective doses of D. esculentum against AD, particularly via amyloidogenic pathway.
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http://dx.doi.org/10.1038/s41598-021-03142-wDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8664832PMC
December 2021

Influence of Plant Origins and Seasonal Variations on Nutritive Values, Phenolics and Antioxidant Activities of Craib., an Endangered Species from Thailand.

Foods 2021 Nov 14;10(11). Epub 2021 Nov 14.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Craib. is an indigenous plant found in Thailand, Cambodia and Vietnam that has become threatened owing to lack of knowledge about its agricultural management. This plant is now rare in the wild and was registered in the Plant Genetic Conservation Project under the initiation of Her Royal Highness Princess Maha Chakri Sirindhorn (RSPG) to promote sustainable conservation and optimally beneficial utilization. has a long history of utilization as a nutrient-rich source with medicinal properties but scientific evidence of the veracity of these claims is limited. Here, the nutritional compositions, phenolic contents and antioxidant activities of different plant parts (young shoots and old leaves) of were investigated using plants collected from four areas of Thailand as Kamphaeng Phet (KP), Muang Nakhon Ratchasima (MN), Pakchong Nakhon Ratchasima (PN) and Uthai Thani (UT) at different harvesting periods (March-April, May-June and July-August). Results indicated that young shoots provided higher energy, protein, fat, dietary fiber, phosphorus, sodium, and zinc than old leaves. By contrast, nutrients such as total sugar, vitamin C, carotenoids, potassium, calcium, magnesium, and iron contents were higher in old leaves that also exhibited higher phenolic contents and most antioxidant activities than young shoots. Generally, most nutrients, phenolic contents, and antioxidant activities exhibited no clear trend among different plant origins. The harvesting period of July-August provided a suitable climate for biosynthesis of most nutrients, while high phenolics were mainly found in samples harvested in March-April. No clear trend was observed in the prevalence of antioxidant activities that varied according to assay techniques.
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http://dx.doi.org/10.3390/foods10112799DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8623237PMC
November 2021

Analysis of Phytonutrients, Anti-Mutagenic and Chemopreventive Effects of Tropical Fruit Extracts.

Foods 2021 Oct 27;10(11). Epub 2021 Oct 27.

Food and Nutrition Academic and Research Cluster, Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Thailand is located in the tropics and a wide variety of fruits are grown commercially. However, studies regarding the phytonutrients, anti-mutagenic and chemopreventive effects of these fruits are limited. Thus, phytochemical profiles and inhibition of key enzymes involved in obesity and diabetes, together with anti-mutagenic and chemopreventive properties of eight tropical fruit extracts cultivated in Thailand, including 'Kimju', 'Keenok', 'Pattavia', 'Phulae', 'Chanee', 'Monthong', 'Khaekdum' and 'Namdokmai' were investigated. Different cultivars were also compared. Results showed that 'Namdokmai' was the most antioxidant-rich extract containing abundant 4-hydroxybenzoic acid and its derivative, gallic acid, as the main phenolics. 'Namdokmai' also exhibited high inhibitory capacities (>60% inhibition under studied conditions) against lipase, α-amylase and α-glucosidase, key enzymes as drug targets for controlling obesity and type 2 diabetes. Interestingly, all fruit extracts suppressed food mutagen-induced DNA mutations assayed by the Ames test, especially 'Namdokmai' and 'Khaekdum' (>50% inhibition at 200 µg/plate). The 'Namdokmai' was also the most potent extract for suppression of cancer promotion (>90% inhibition at 200 µg/mL) followed by 'Kimju', 'Keenok' and 'Khaekdum'. Results potentially indicated that fruit intake after overcooked meat consumption might supplement nutrients and fiber and also reduce DNA mutation sources.
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http://dx.doi.org/10.3390/foods10112600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8621897PMC
October 2021

Phytochemicals and In Vitro Bioactivities of Aqueous Ethanolic Extracts from Common Vegetables in Thai Food.

Plants (Basel) 2021 Jul 29;10(8). Epub 2021 Jul 29.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Non-communicable diseases (NCDs) are the leading global cause of death. The World Health Organization (WHO) has endorsed the consumption of fruits and vegetables because they are rich in phytochemicals that sustainably ameliorate the occurrence of NCDs. Thai food contains many spices and vegetables with recognized health benefits. Quality control of plant samples encountered a bottleneck in the field and comparative studies of plant control origins including species or cultivar identification, growing area and appropriate harvesting time are limited. To address this issue, all plant samples used in this study were cultivated and controlled by the Department of Agriculture, Ministry of Agriculture and Cooperatives, Thailand. The samples were phytochemically screened and determined their health-promoting bioactivities via antioxidant activities and inhibition of NCD-related enzymes including lipase (obesity), α-amylase and α-glucosidase (diabetes), angiotensin-converting enzyme (hypertension), as well as acetylcholinesterase, butyrylcholinesterase and β-secretase (Alzheimer's disease). The non-enzymatic reaction toward glycation was also evaluated. The results showed that subsp. (Lace) Maslin, Seigler & Ebinger, DC. and 'Kermit' extracts exhibited high antioxidant activities. Moreover, DC. extract was a potent inhibitor against lipase, angiotensin-converting enzyme and butyrylcholinesterase, while L. and (L.) DC. were potent anti-diabetic agents and subsp. (Lace) Maslin, and Seigler & Ebinger was a potent anti-glycation agent. Our data provide a comparative analysis of ten vegetables to encourage healthy food consumption and development to control NCDs in Thailand in the future.
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http://dx.doi.org/10.3390/plants10081563DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8400534PMC
July 2021

Development of Chrysin Loaded Oil-in-Water Nanoemulsion for Improving Bioaccessibility.

Foods 2021 Aug 18;10(8). Epub 2021 Aug 18.

Nano Agricultural Chemistry and Processing Research Team, National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Klong Luang, Pathum Thani 12120, Thailand.

Chrysin (5,7-dihydroxyflavone) is a remarkable flavonoid exhibiting many health-promoting activities, such as antioxidant, anti-inflammatory, and anti-Alzheimer's disease (AD). Nevertheless, chrysin has been addressed regarding its limited applications, due to low bioaccessibility. Therefore, to improve chrysin bioaccessibility, a colloidal delivery system involving nanoemulsion was developed as chrysin nanoemulsion (chrysin-NE) using an oil-in-water system. Our results show that chrysin can be loaded by approximately 174.21 µg/g nanoemulsion (100.29 ± 0.53% ) when medium chain triglyceride (MCT) oil was used as an oil phase. The nanocolloidal size, polydispersity index, and surface charge of chrysin-NE were approximately 161 nm, 0.21, and -32 mV, respectively. These properties were stable for at least five weeks at room temperature. Furthermore, in vitro chrysin bioactivities regarding antioxidant and anti-AD were maintained as pure chrysin, suggesting that multistep formulation could not affect chrysin properties. Interestingly, the developed chrysin-NE was more tolerant of gastrointestinal digestion and significantly absorbed by the human intestinal cells (Caco-2) than pure chrysin. These findings demonstrate that the encapsulation of chrysin using oil-in-water nanoemulsion could enhance the bioaccessibility of chrysin, which might be subsequently applied to food and nutraceutical industries.
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http://dx.doi.org/10.3390/foods10081912DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8392734PMC
August 2021

A Comparison of the Nutritional and Biochemical Quality of Date Palm Fruits Obtained Using Different Planting Techniques.

Molecules 2021 Apr 13;26(8). Epub 2021 Apr 13.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Date palm fruit ( L.) is commonly consumed around the world and has recently become an economical crop in Eastern Thailand, especially the Barhi cultivar that can be consumed as fresh fruit. To maintain genetic qualities, date palm is populated through cell culture. This leads to high production costs, while access to this technique is limited. Increasing date palm population by simple seed planting is currently of interest as an alternative for local farmers. Nevertheless, information on nutritive values, bioactive compounds, and health-promoting bioactivities of seed originating from date palm fruit is unavailable. Effects of different planting origins (cell culture origin (CO) and seed origin (SO)) of date palm fruits at the Khalal stage of Barhi cultivar were investigated for nutritive values, bioactive compounds, and in vitro health-promoting properties via key enzyme inhibitions against obesity (lipase), diabetes (α-amylase, α-glucosidase, and dipeptidyl peptidase-IV), Alzheimer's disease (cholinesterases and β-secretase), and hypertension (angiotensin-converting enzyme). Waste seeds as a by-product from date palm production were also examined regarding these properties to increase seed marketing opportunities for future food applications and other health-related products. CO and SO exhibited insignificant differences in energy, fat, and carbohydrate contents. SO had higher protein, dietary fiber, vitamin A, vitamin E, and calcium contents than CO, while CO contained higher contents of fructose, glucose and maltose. Higher phenolic contents in SO led to greater enzyme inhibitory activities than CO. Interestingly, seeds of date palm fruits mostly contained higher nutritive values than the flesh. No carotenoids were detected in seeds but higher phenolic contents resulted in greater enzyme inhibitory activities than recorded for fruit flesh. Results suggest that appropriate planting of date palm can support the development of novel date palm fruit products, leading to expansion of economic opportunities and investment in date palm fruit agriculture.
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http://dx.doi.org/10.3390/molecules26082245DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8069938PMC
April 2021

Health-promoting bioactivity and in vivo genotoxicity evaluation of a hemiepiphyte fig, .

Food Sci Nutr 2021 Apr 3;9(4):2269-2279. Epub 2021 Mar 3.

Institute of Nutrition Mahidol University Salaya, Phuttamonthon Nakhon Pathom Thailand.

species have been used as a typical component in food and folk medicine in Asia for centuries. However, little is known regarding the bioactivity and genotoxicity of the recently identified (FD), an indigenous plant of the tropical evergreen rain forest. FD is unique from other species because of its highly sought-after red-brown latex. Antioxidant properties together with phenolic and flavonoid contents of FD were elucidated. Health-promoting characteristics were examined by studying the inhibition of enzymes as a drug target for diabetes, hypertension, Alzheimer's disease, and obesity, together with anticancer ability against human colorectal adenocarcinoma, human hepatocellular carcinoma, human ovarian carcinoma, human prostate adenocarcinoma, and human lung carcinoma. Besides, FD genotoxicity was tested using the wing spot test. Results showed that both FD root and latex exhibited antioxidant activity due to the presence of phenolics and flavonoids, specifically caffeic acid and cyanidin. The ethanolic fraction of FD root demonstrated a potent antidiabetic mechanism underlying α-glucosidase inhibitory activity similar to acarbose. This fraction also suppressed lung and ovarian cancer growth, possibly by G1 and G2/M arrest, respectively. All tested fractions lacked mutagenicity in vivo. Results indicated that FD can be developed as novel antidiabetic compounds; however, its bioactive compounds should be further identified.
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http://dx.doi.org/10.1002/fsn3.2205DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020917PMC
April 2021

In Vitro Phytotherapeutic Properties of Aqueous Extracted Craib. towards Civilization Diseases.

Molecules 2021 Feb 18;26(4). Epub 2021 Feb 18.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Craib. is an indigenous edible plant that became an endangered species due to limited consumption of the local population with unknown reproduction and growth conditions. The plant is used as a traditional herb; however, its health applications lack scientific-based evidence. Craib. plant parts (old leaves and young shoots) from four areas as Kamphaeng Phet (KP), Muang Nakhon Ratchasima (MN), Pakchong Nakhon Ratchasima (PN), and Uthai Thani (UT) origins were investigated for phenolic compositions and in vitro health properties through the inhibition of key enzymes relevant to obesity (lipase), diabetes (α-glucosidase and dipeptidyl peptidase-IV), Alzheimer's disease (cholinesterases and β-secretase), and hypertension (angiotensin-converting enzyme). Phenolics including -coumaric acid, sinapic acid, naringenin, and apigenin were detected in old leaves and young shoots in all plant origins. Old leaves exhibited higher total phenolic contents (TPCs) and total flavonoid contents (TFCs), leading to higher enzyme inhibitory activities than young shoots. Besides, PN and MN with higher TPCs and TFCs tended to exhibit greater enzyme inhibitory activities than others. These results will be useful to promote this plant as a healthy food with valuable medicinal capacities to support its consumption and agricultural stimulation, leading to sustainable conservation of this endangered species.
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http://dx.doi.org/10.3390/molecules26041082DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7922288PMC
February 2021

The Effect of Steaming and Fermentation on Nutritive Values, Antioxidant Activities, and Inhibitory Properties of Tea Leaves.

Foods 2021 Jan 8;10(1). Epub 2021 Jan 8.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Fermented tea (Cha-miang in Thai) is a local product made by traditional food preservation processes in Northern Thailand that involve steaming fresh tea leaves followed by fermenting in the dark. Information on changes in nutritive values, bioactive compounds, antioxidant activities, and health properties that occur during the steaming and fermenting processes of tea leaves is, however, limited. Changes in nutritive values, phenolics, antioxidant activities, and in vitro health properties through inhibition of key enzymes that control obesity (lipase), diabetes (α-amylase and α-glucosidase), hypertension (angiotensin-converting enzyme (ACE)), and Alzheimer's disease (cholinesterases (ChEs) and β-secretase (BACE-1)) of fermented tea were compared to the corresponding fresh and steamed tea leaves. Results showed that energy, carbohydrate, and vitamin B1 increased after steaming, while most nutrients including protein, dietary fiber, vitamins (B2, B3, and C), and minerals (Na, K, Ca, Mg, Fe, and Zn) decreased after the steaming process. After fermentation, energy, fat, sodium, potassium, and iron contents increased, while calcium and vitamins (B1, B2, B3, and C) decreased compared to steamed tea leaves. However, the contents of vitamin B1 and iron were insignificantly different between fresh and fermented tea leaves. Five flavonoids (quercetin, kaempferol, cyanidin, myricetin, and apigenin) and three phenolic acids (gallic acid, caffeic acid, and -coumaric acid) were identified in the tea samples. Total phenolic content (TPC) and antioxidant activities increased significantly after steaming and fermentation, suggesting structural changes in bioactive compounds during these processes. Steamed tea exhibited high inhibition against lipase, α-amylase, and α-glucosidase, while fermented tea possessed high anti-ChE and anti-ACE activities. Fresh tea exhibited high BACE-1 inhibitory activity. Results suggest that tea preparations (steaming and fermentation) play a significant role in the amounts of nutrients and bioactive compounds, which, in turn, affect the in vitro health properties. Knowledge gained from this research will support future investigations on in vivo health properties of fermented tea, as well as promote future food development of fermented tea as a healthy food.
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http://dx.doi.org/10.3390/foods10010117DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7827290PMC
January 2021

Investigation of Anthocyanidins and Anthocyanins for Targeting α-Glucosidase in Diabetes Mellitus.

Prev Nutr Food Sci 2020 Sep;25(3):263-271

Institute of Nutrition, Mahidol University, Phutthamonthon, Nakhon Pathom 73170, Thailand.

Anthocyanidins are bioactive compounds found mostly in colored plants and fruits. Consumption of anthocyanidin-rich foods has been shown to reduce the risk of diabetes. However, limited information is available regarding the inhibitory effect and interactions of anthocyanidins on α-glucosidase, the key enzyme that controls diabetes through degrading carbohydrate. Therefore, we used computational docking analysis to investigate the degree and type of inhibition by α-glucosidase, and the structural interactions of enzyme-selected anthocyanidins. The results suggested that anthocyanidins exhibit half maximal inhibitory concentration of 4∼55 μM; the strongest and weakest α-glucosidase inhibitors were delphinidin and malvidin, respectively. Indeed, delphinidin inhibits α-glucosidase in a mixed type, close to non-competitive manner with an inhibitory constant of 78 nM. Addition of a glycoside (glucoside or galactoside) at C3 on the C ring of delphinidin significantly decreased inhibitory activity, and addition of glycosides at C3 on the C ring and C5 on the A ring of delphinidin prevented all inhibitory activity. Molecular docking and free binding energy accurately confirmed the mode of inhibition determined by enzyme kinetics. These data will inform the use of alternative sources of anthocyanidins in functional foods and dietary supplements for prevention of diabetes. The results provide useful information for evaluating possible molecular models using anthocyanins/anthocyanidins as templates and α-glucosidase as the key enzyme in management of diabetes.
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http://dx.doi.org/10.3746/pnf.2020.25.3.263DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7541926PMC
September 2020

Inhibitory effects of Gymnema inodorum (Lour.) Decne leaf extracts and its triterpene saponin on carbohydrate digestion and intestinal glucose absorption.

J Ethnopharmacol 2021 Feb 21;266:113398. Epub 2020 Sep 21.

National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, Thailand. Electronic address:

Ethnopharmacological Relevance: Chiang-Da, Gymnema inodorum (Lour.) Decne. (GI), is an ethnomedicinal plant that has been used for diabetic treatment since ancient times. One of the anti-diabetic mechanisms is possibly related to the actions of triterpene glycoside, (3β, 16β)-16,28-dihydroxyolean-12-en-3-yl-O-β-D-glucopyranosyl-β-D-glucopyranosiduronic acid (GIA1) in decreasing carbohydrate digestive enzymes and intestinal glucose absorption in the gut system.

Aims Of The Study: To observe the amount of GIA1 in GI leaf extracts obtained from different ethanol concentrations and to investigate the anti-hyperglycemic mechanisms of the extracts and GIA1.

Materials And Methods: The crude extracts were prepared using 50%v/v to 95%v/v ethanol solutions and used for GIA1 isolation. The anti-hyperglycemic models included in our study examined the inhibitory activities of α-amylase/α-glucosidase and intestinal glucose absorption related to sodium glucose cotransporter type 1 (SGLT1) using Caco-2 cells.

Results: GIA1 was found about 8%w/w to 18%w/w in the GI extract depending on ethanol concentrations. The GI extracts and GIA1 showed less inhibitory activities on α-amylase. The extracts from 75%v/v and 95%v/v ethanol and GIA1 significantly delayed the glycemic absorption by lowering α-glucosidase activity and glucose transportation of SGLT1. However, the 50%v/v ethanolic extract markedly decreased the α-glucosidase activity than the SGLT1 function.

Conclusion: Differences in the GIA1 contents and anti-glycemic properties of the GI leaf extract was dependent on ethanol concentrations. Furthermore, the inhibitory effects of the 75%v/v and 95%v/v ethanolic extracts on α-glucosidase and SGLT1 were relevant to GIA1 content.
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http://dx.doi.org/10.1016/j.jep.2020.113398DOI Listing
February 2021

Phenolic Profiles, Antioxidant, and Inhibitory Activities of (Roxb.) Craib and (Lem.) A.C. Sm.

Foods 2020 Sep 2;9(9). Epub 2020 Sep 2.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

spp. in the Schisandraceae family are woody vine plants, which produce edible red fruits that are rich in nutrients and antioxidant activities. Despite their valuable food applications, spp. are only able to grow naturally in the forest, and reproduction handled by botanists is still in progress with a very low growth rate. Subsequently, spp. were listed as endangered species by the International Union for Conservation of Nature and Natural Resources (IUCN) in 2011. Two different spp., including (Lem.) A.C. Sm. and (Roxb.) Craib, are mostly found in northern Thailand. These rare, wild fruits are unrecognizable to outsiders, and there have only been limited investigations into its biological properties. This study, therefore, aimed to comparatively investigate the phenolic profiles, antioxidant activities, and inhibitory activities against the key enzymes involved in diabetes (α-glucosidase and α-amylase) and Alzheimer's disease (acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and beta-secretase 1 (BACE-1)) in different fruit parts (exocarp, mesocarp (edible part), seed, and core) of (Lem.) A.C. Sm. and (Roxb.) Craib. The results suggested that Kadsura spp. extracts were rich in flavonol (quercetin), flavanone (naringenin), anthocyanidins (cyanidin and delphinidin), and anthocyanins (cyanidin 3--glucoside (kuromanin), cyanidin 3--galactoside (ideain), cyanidin 3--rutinoside (keracyanin), and cyanidin 3,5-di--glucoside (cyanin)). These flavonoids were found to be responsible for the high antioxidant activities and key enzyme inhibitions detected in spp. extracts. The findings of the present study can support further development of spp. as a potential source of phenolics and anti-oxidative agents with health benefits against diabetes and Alzheimer's disease. Besides, exocarp and the core of Kadsura spp. exhibited higher phenolic contents, antioxidant activities, and key enzyme inhibitory activities compared to the mesocarp and seeds, respectively. This information can promote the use of fruit parts other than the edible mesocarp for future food applications using spp. rather than these being wasted.
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http://dx.doi.org/10.3390/foods9091222DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7555767PMC
September 2020

The Effect of Sacred Lotus () and Its Mixtures on Phenolic Profiles, Antioxidant Activities, and Inhibitions of the Key Enzymes Relevant to Alzheimer's Disease.

Molecules 2020 Aug 14;25(16). Epub 2020 Aug 14.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Sacred lotus () has long been used as a food source and ingredient for traditional herbal remedies. Plant parts contain neuroprotective agents that interact with specific targets to inhibit Alzheimer's disease (AD). Organic solvents including methanol, ethyl acetate, hexane, and -butanol, are widely employed for extraction of sacred lotus but impact food safety. Seed embryo, flower stalk, stamen, old leaf, petal, and leaf stalk of sacred lotus were extracted using hot water (aqueous extraction). The extractions were analyzed for their bioactive constituents, antioxidant and anti-AD properties as key enzyme inhibitory activities toward acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-secretase 1 (BACE-1). Results showed that the sacred lotus stamen exhibited significant amounts of phenolics, including phenolic acids and flavonoids, that contributed to high antioxidant activity via both single electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms, with anti-AChE, anti-BChE, and anti-BACE-1 activities. To enhance utilization of other sacred lotus parts, a combination of stamen, old leaf and petal as the three sacred lotus plant components with the highest phenolic contents, antioxidant activities, and enzyme inhibitory properties was analyzed. Antagonist interaction was observed, possibly from flavonoids-flavonoids interaction. Further in-depth elucidation of this issue is required. Findings demonstrated that an aqueous extract of the stamen has potential for application as a functional food to mitigate the onset of Alzheimer's disease.
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http://dx.doi.org/10.3390/molecules25163713DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7463813PMC
August 2020

Nutritional composition of conserved spp. plants in Northern Thailand.

Heliyon 2020 Jul 16;6(7):e04451. Epub 2020 Jul 16.

Institute of Nutrition, Mahidol University, Phutthamonthon, Nakhon Pathom, 73170, Thailand.

The genus comprises woody vine plants belonging to the family . Species are found mostly in Northern Thailand and widely consumed by the local population. Occurrences of these wild fruits are rare as they only grow naturally in forest areas. Nutritive values of spp. remain unclear, leading to improper management for food applications. Nutritional composition of spp. was evaluated to promote sustainable conservation. Nutritive values in different fruits parts (exocarp, mesocarp, seed and core) of two species as (Lem.) A.C. Sm. and (Roxb.) Craib, from Chiang Rai Province, Thailand were assessed. When comparing nutritional contents based on per 100 g dry weight, results suggested that exhibited higher carbohydrate (1-2 times), sugar (1-2 times) and vitamin C (3-4 times) contents than , while the latter possessed higher fat (1-2 times), protein (1.6-1.9 times), and dietary fiber (1.5-1.8 times) contents. Considering each fruit part, the mesocarp (the only edible fruit part) and exocarp of both species provided high dietary fiber (11.6-20.9% recommended dietary fiber) and vitamin C (as high as 73% recommended per day) but were low in energy (30-40 kcal/100 g fresh weight), protein (0.6-1.2% recommended per day), fat (0.5-1.8% recommended per day) and sugar (2.4-5.4% recommended per day). Interestingly, seed contained higher energy (1-2 times), protein (2-3 times) and fat (4-50 times) than the other fruit parts. Results support the potential consumption of spp. as a healthy fruit that can be used for future food applications. Seed and exocarp from spp. also showed potential for new product development.
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http://dx.doi.org/10.1016/j.heliyon.2020.e04451DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7365980PMC
July 2020

Comparison of Phytochemicals, Antioxidant, and In Vitro Anti-Alzheimer Properties of Twenty-Seven spp. Cultivated in Thailand.

Molecules 2020 Jun 3;25(11). Epub 2020 Jun 3.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder. To fight the disease, natural products, including mulberry, with antioxidant activities and inhibitory activities against key enzymes (acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and beta-secretase 1 (BACE-1)) are of interest. However, even in the same cultivars, mulberry trees grown in different populated locations might possess disparate amounts of phytochemical profiles, leading to dissimilar health properties, which cause problems when comparing different cultivars of mulberry. Therefore, this study aimed to comparatively investigate the phytochemicals, antioxidant activities, and inhibitory activities against AChE, BChE, and BACE-1, of twenty-seven spp. cultivated in the same planting area in Thailand. The results suggested that fruit samples were rich in phenolics, especially cyanidin, kuromanin, and keracyanin. Besides, the aqueous fruit extracts exhibited antioxidant activities, both in single electron transfer (SET) and hydrogen atom transfer (HAT) mechanisms, while strong inhibitory activities against AD key enzymes were observed. Interestingly, among the twenty-seven spp., sp. code SKSM 810191 with high phytochemicals, antioxidant activities and in vitro anti-AD properties is a promising cultivar for further developed as a potential mulberry resource with health benefits against AD.
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http://dx.doi.org/10.3390/molecules25112600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7321130PMC
June 2020

Mulberry Fruit Cultivar 'Chiang Mai' Prevents Beta-Amyloid Toxicity in PC12 Neuronal Cells and in a Model of Alzheimer's Disease.

Molecules 2020 Apr 16;25(8). Epub 2020 Apr 16.

Institute of Nutrition, Mahidol University, Salaya, Phuttamonthon, Nakhon Pathom 73170, Thailand.

Alzheimer's disease (AD) is the most common form of dementia, characterized by chronic neuron loss and cognitive problems. Aggregated amyloid beta (Aβ) peptides, a product of cleaved amyloid precursor protein (APP) by beta-secretase 1 (BACE-1), have been indicated for the progressive pathogenesis of AD. Currently, screening for anti-AD compounds in foodstuffs is increasing, with promising results. Hence, the purpose of this study was to investigate the extraction conditions, phytochemical contents, and anti-AD properties, targeting Aβ peptides of cf. 'Chiang Mai' (MNCM) both in vitro and in vivo. Data showed that the aqueous extract of MNCM contained high amounts of cyanidin, keracyanin, and kuromanin as anthocyanidin and anthocyanins. The extract also strongly inhibited cholinesterases and BACE-1 in vitro. Moreover, MNCM extract prevented Aβ-induced neurotoxicity and promoted neurite outgrowth in neuronal cells. Interestingly, MNCM extract reduced Aβ peptides and improved locomotory coordination of co-expressing human APP and BACE-1, specifically in the brain. These findings suggest that MNCM may be useful as an AD preventive agent by targeting Aβ formation.
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http://dx.doi.org/10.3390/molecules25081837DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7221829PMC
April 2020

Bioactive Compounds, Antioxidant Activity and Inhibition of Key Enzymes Relevant to Alzheimer's Disease from Sweet Pepper () Extracts.

Prev Nutr Food Sci 2019 Sep 30;24(3):327-337. Epub 2019 Sep 30.

Institute of Nutrition, Mahidol University, Phutthamonthon, Nakhon Pathom 73170, Thailand.

Sweet pepper is a non-pungent chili of the species and is an important ingredient in daily diets due to its characteristics such as pungency, aromas, and flavors. Sweet pepper is a rich source of bioactive compounds such as phenols, carotenoids, and flavonoids, which can promote potential health benefits against various non-communicable diseases. However, research focused on anti-Alzheimer's disease (AD) properties of sweet peppers is limited. Thus, this study aimed investigate bioactive compounds (flavonoids, phenolic acids, and carotenoids), antioxidant activity and anti-AD properties of four colored sweet peppers (green, red, orange, and yellow) via their abilities to inhibit key enzymes relevant to AD [acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-secretase (BACE1)]. Extraction solvents [hexane, ethyl acetate, and 70% (v/v) aqueous ethanol] were also investigated. Results suggested that yellow sweet pepper have the highest content of flavonoids, while green sweet pepper have the highest contents of phenolic acids and red sweet peppers have the highest content of carotenoids. In terms of anti-AD properties, green sweet peppers exhibited the highest antioxidant, anti-BChE, and anti-BACE1 activities; however, yellow sweet pepper extract exhibited the highest amounts of AChE inhibition. Bioactive compounds in sweet red peppers may therefore have anti-AD properties, and may be useful for AD prevention.
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http://dx.doi.org/10.3746/pnf.2019.24.3.327DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6779089PMC
September 2019

The Effect of Coconut Jelly with Stevia as a Natural Sweetener on Blood Glucose, Insulin and C-Peptide Responses in Twelve Healthy Subjects.

Recent Pat Food Nutr Agric 2018 ;9(2):127-133

Institute of Nutrition, Mahidol University, 999 Phutthamonthon 4 Rd., Salaya, Phutthamonthon, Nakhon Pathom 73170, Thailand.

Background: Coconut jelly is a popular dessert among Asian people. However, it contains high levels of sugar. The recent patents on steviol glycoside (WO2015014969A1), steviol glycoside compositions for oral ingestion or use (WO2017095932A1) and sweetener composition for preventing and improving obesity, containing glycolysis inhibitor ingredient (EP2756764B1) help to select the sweetener for development of coconut jelly.

Objective: Therefore, the purposes of this study were to develop a healthier coconut jelly formula by using stevia as a natural sweetener as well as to investigate the short-term effects of Modified Coconut Jelly (MCJ) compared to Control Formula (CCJ) consumption on glycemic and insulin responses in twelve healthy participants.

Methods: The sensory evaluation found that MCJ with 50% sugar replacement using stevia obtained the highest acceptability score compared to other formulas. In a cross-over design, participants were required to consume MCJ and CCJ containing 50 g of available carbohydrates. Blood samples were collected at 0 (baseline), 30, 60, 90 and 120 minutes for postprandial blood glucose, insulin, and C-peptide.

Results: The incremental Areas Under the Curve (iAUC) of blood glucose and insulin of MCJ had a lower trend than CCJ by 15.7 and 5.4 percent, respectively. MCJ consumption had blood glucose slowly decline after 60 to 120 minute. MCJ tended to decrease in postprandial blood glucose level without inducing insulin secretion.

Conclusion: This might be an effect of stevia. Nutrient composition is lower in total sugar and higher in fiber, which has been reported as antihyperglycemia in humans. Therefore, MCJ might be an optional food product for healthy people or patients with Non-Communicable Diseases (NCDs) such as diabetes mellitus.
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http://dx.doi.org/10.2174/2212798410666180717163852DOI Listing
January 2019

Impact of Genetic Polymorphism on LDL-C Response to Plant Stanol Ester Intake.

J Med Assoc Thai 2016 Jun;99(6):723-31

Background: The high blood cholesterol level could be prevented by plant stanol ester (Staest) consumption. In addition, the genetic polymorphism of cholesterol transporters might be related with lipid profile and subsequently response to Staest intake.

Objective: To investigate the effect of single nucleotide polymorphism in ATP-binding cassette hetero-dimeric G5/G8 (ABCG5/G8) and Niemann-Pick C1 Like1 protein (NPC1L1) gene on LDL-C response subsequent to plant Staest intake in Thai Subjects.

Material And Method: The blood samples were collected from 113 subjects for genotyping. The single nucleotide polymorphisms (SNPs) of ABCG5/G8 positions; rs6720173 (Q604E), rs4148211 (C54Y), rs4148217 (T400K), rs3806471 (5’UTR-145), and NPC1L1; positon; rs2072183 (L272L) were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Results: After Staest intake, the subjects with QE genotype (Q604E of ABCG5) showed a 4-fold significant decrease in LDL-C level (14.17±10.67%) compared to subjects with QQ genotype (3.50±10.65%) (p = 0.003). Moreover, the pronounced effect of Q604E polymorphism was observed in subjects after intake of Staest with meal. However, no significant difference in these markers was observed in subjects carrying other mutations.

Conclusion: Thus, it could be suggested that non-synonymous gene polymorphism resulted substitution of uncharged glutamine (Q) with negatively charged glutamic acid (E) at position 604, thereby possibly alter the function of transporter proteins. Besides, the genetic variation in these genes might be related with serum lipid profiles. Moreover, Q604E mutation of ABCG5 in each individual with meal effect could lead to particular response towards LDL-C level after Staest intervention.
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June 2016

Modulating glyoxalase I metal selectivity by deletional mutagenesis: underlying structural factors contributing to nickel activation profiles.

Metallomics 2015 Apr;7(4):605-12

Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada.

Metabolically produced methylglyoxal is a cytotoxic compound that can lead to covalent modification of cellular DNA, RNA and protein. One pathway to detoxify this compound is via the glyoxalase enzyme system. The first enzyme of this detoxification system, glyoxalase I (GlxI), can be divided into two classes according to its metal activation profile, a Zn(2+)-activated class and a Ni(2+)-activated class. In order to elucidate some of the key structural features required for selective metal activation by these two classes of GlxI, deletional mutagenesis was utilized to remove, in a step-wise fashion, a key α-helix (residues 73-87) and two small loop regions (residues 99-103 and 111-114) from the Zn(2+)-activated Pseudomonas aeruginosa GlxI (GloA3) in order to mimic the smaller Ni(2+)-activated GlxI (GloA2) from the same organism. This approach was observed to clearly shift the metal activation profile of a Zn(2+)-activated class GlxI into a Ni(2+)-activated class GlxI enzyme. The α-helix structural component was found to contribute significantly toward GlxI metal specificity, while the two small loop regions were observed to play a more crucial role in the magnitude of the enzymatic activity. The current study should provide additional information on the fundamental relationship of protein structure to metal selectivity in these metalloenzymes.
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http://dx.doi.org/10.1039/c4mt00299gDOI Listing
April 2015

The crystal structure of a homodimeric Pseudomonas glyoxalase I enzyme reveals asymmetric metallation commensurate with half-of-sites activity.

Chemistry 2015 Jan 19;21(2):541-4. Epub 2014 Nov 19.

School of Chemistry and Biochemistry, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Western Australia (Australia).

The Zn inactive class of glyoxalase I (Glo1) metalloenzymes are typically homodimeric with two metal-dependent active sites. While the two active sites share identical amino acid composition, this class of enzyme is optimally active with only one metal per homodimer. We have determined the X-ray crystal structure of GloA2, a Zn inactive Glo1 enzyme from Pseudomonas aeruginosa. The presented structures exhibit an unprecedented metal-binding arrangement consistent with half-of-sites activity: one active site contains a single activating Ni(2+) ion, whereas the other contains two inactivating Zn(2+) ions. Enzymological experiments prompted by the binuclear Zn(2+) site identified a novel catalytic property of GloA2. The enzyme can function as a Zn(2+) /Co(2+) -dependent hydrolase, in addition to its previously determined glyoxalase I activity. The presented findings demonstrate that GloA2 can accommodate two distinct metal-binding arrangements simultaneously, each of which catalyzes a different reaction.
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http://dx.doi.org/10.1002/chem.201405402DOI Listing
January 2015

Ni2+-activated glyoxalase I from Escherichia coli: substrate specificity, kinetic isotope effects and evolution within the βαβββ superfamily.

J Inorg Biochem 2012 Mar 28;108:133-40. Epub 2011 Nov 28.

Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada.

The Escherichia coli glyoxalase system consists of the metalloenzymes glyoxalase I and glyoxalase II. Little is known regarding Ni(2+)-activated E. coli glyoxalase I substrate specificity, its thiol cofactor preference, the presence or absence of any substrate kinetic isotope effects on the enzyme mechanism, or whether glyoxalase I might catalyze additional reactions similar to those exhibited by related βαβββ structural superfamily members. The current investigation has shown that this two-enzyme system is capable of utilizing the thiol cofactors glutathionylspermidine and trypanothione, in addition to the known tripeptide glutathione, to convert substrate methylglyoxal to non-toxic D-lactate in the presence of Ni(2+) ion. E. coli glyoxalase I, reconstituted with either Ni(2+) or Cd(2+), was observed to efficiently process deuterated and non-deuterated phenylglyoxal utilizing glutathione as cofactor. Interestingly, a substrate kinetic isotope effect for the Ni(2+)-substituted enzyme was not detected; however, the proton transfer step was observed to be partially rate limiting for the Cd(2+)-substituted enzyme. This is the first non-Zn(2+)-activated GlxI where a metal ion-dependent kinetic isotope effect using deuterium-labelled substrate has been observed. Attempts to detect a glutathione conjugation reaction with the antibiotic fosfomycin, similar to the reaction catalyzed by the related superfamily member FosA, were unsuccessful when utilizing the E. coli glyoxalase I E56A mutein.
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http://dx.doi.org/10.1016/j.jinorgbio.2011.11.008DOI Listing
March 2012

Structural variation in bacterial glyoxalase I enzymes: investigation of the metalloenzyme glyoxalase I from Clostridium acetobutylicum.

J Biol Chem 2011 Nov 13;286(44):38367-38374. Epub 2011 Sep 13.

Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada. Electronic address:

The glyoxalase system catalyzes the conversion of toxic, metabolically produced α-ketoaldehydes, such as methylglyoxal, into their corresponding nontoxic 2-hydroxycarboxylic acids, leading to detoxification of these cellular metabolites. Previous studies on the first enzyme in the glyoxalase system, glyoxalase I (GlxI), from yeast, protozoa, animals, humans, plants, and Gram-negative bacteria, have suggested two metal activation classes, Zn(2+) and non-Zn(2+) activation. Here, we report a biochemical and structural investigation of the GlxI from Clostridium acetobutylicum, which is the first GlxI enzyme from Gram-positive bacteria that has been fully characterized as to its three-dimensional structure and its detailed metal specificity. It is a Ni(2+)/Co(2+)-activated enzyme, in which the active site geometry forms an octahedral coordination with one metal atom, two water molecules, and four metal-binding ligands, although its inactive Zn(2+)-bound form possesses a trigonal bipyramidal geometry with only one water molecule liganded to the metal center. This enzyme also possesses a unique dimeric molecular structure. Unlike other small homodimeric GlxI where two active sites are located at the dimeric interface, the C. acetobutylicum dimeric GlxI enzyme also forms two active sites but each within single subunits. Interestingly, even though this enzyme possesses a different dimeric structure from previously studied GlxI, its metal activation characteristics are consistent with properties of other GlxI. These findings indicate that metal activation profiles in this class of enzyme hold true across diverse quaternary structure arrangements.
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http://dx.doi.org/10.1074/jbc.M111.251603DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3207458PMC
November 2011

Bacterial glyoxalase enzymes.

Semin Cell Dev Biol 2011 May 15;22(3):285-92. Epub 2011 Feb 15.

Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada.

The glyoxalase system is composed of two metalloenzymes, Glyoxalase I and Glyoxalase II. This system is important in the detoxification of methylglyoxal, among other roles. Detailed studies have determined that a number of bacterial Glyoxalase I enzymes are maximally activated by Ni(2+) and Co(2+) ions, but are inactive in the presence of Zn(2+). This is in contrast to the Glyoxalase I enzyme from humans, which is catalytically active with Zn(2+) as well as a number of other metal ions. The structure-activity relationships between these two classes of Glyoxalase I are serving as important clues to how the molecular structures of these proteins control metal activation profiles as well as to clarify the mechanistic chemistry of these catalysts. In addition, the possibility of targeting inhibitors against the bacterial versus human enzyme has the potential to lead to new approaches to combat bacterial infections.
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http://dx.doi.org/10.1016/j.semcdb.2011.02.004DOI Listing
May 2011
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