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Fulltext Antifreeze Proteins and Their Practical Utilization in Industry, Medicine, and Agriculture

Eskandari A, Leow TC, Rahman MBA, Oslan SN

Biomolecules, 2020 12 09;10(12).
PMID: 33317024 DOI: 10.3390/biom10121649

Antifreeze proteins (AFPs) are specific proteins, glycopeptides, and peptides made by different organisms to allow cells to survive in sub-zero conditions. AFPs function by reducing the water's freezing point and avoiding ice crystals' growth in the frozen stage. Their capability in modifying ice growth leads to the stabilization of ice crystals within a given temperature range and the inhibition of ice recrystallization that decreases the drip loss during thawing. This review presents the potential applications of AFPs from different sources and types. AFPs can be found in diverse sources such as fish, yeast, plants, bacteria, and insects. Various sources reveal different α-helices and β-sheets structures. Recently, analysis of AFPs has been conducted through bioinformatics tools to analyze their functions within proper time. AFPs can be used widely in various aspects of application and have significant industrial functions, encompassing the enhancement of foods' freezing and liquefying properties, protection of frost plants, enhancement of ice cream's texture, cryosurgery, and cryopreservation of cells and tissues. In conclusion, these applications and physical properties of AFPs can be further explored to meet other industrial players. Designing the peptide-based AFP can also be done to subsequently improve its function.

Matched MeSH terms: Ice Cream
Vortex-assisted liquid-liquid-liquid microextraction followed by high performance liquid chromatography for the simultaneous determination of fourteen phenolic acids in honey, iced tea and canned coffee drinks

Shalash M, Makahleh A, Salhimi SM, Saad B

Talanta, 2017 Nov 01;174:428-435.
PMID: 28738603 DOI: 10.1016/j.talanta.2017.06.039

A vortex-assisted liquid-liquid-liquid microextraction method followed by high performance liquid chromatography-diode array detection for the determination of fourteen phenolic acids (cinnamic, m-coumaric, chlorogenic, syringic, ferulic, o-coumaric, p-coumaric, vanillic, p-hydroxybenzoic, caffeic, 2, 4-dihydroxybenzoic, sinapic, gentisic and gallic acids) in honey, iced tea and canned coffee drink samples has been developed. The separation was achieved using a Poroshell 120-EC-C18 column under a gradient elution at a flow rate of 0.6mLmin-1 and mobile phase composed of methanol and acetic acid (1%, v/v). Under the optimum chromatographic conditions, the fourteen phenolic acids were separated in less than 32min. The extraction was performed using a small volume (400µL) of ternary organic solvents (1-pentanol, propyl acetate and 1-hexanol) dispersed into the aqueous sample (10mL) and assisted by vortex agitation (2500rpm for 45s), the analytes were next back-extracted from the organic solvent using 0.02M KOH (40µL) with vortex speed and time of 2500rpm and 60s, respectively. Under these conditions, enrichment factors of 30-193-fold were achieved. The limits of detection (LODs) were 0.05-0.68µgL-1. Recoveries in honey, iced tea and canned coffee drinks were in the range 72.2-112%. The method was successfully applied for the determination of the phenolic acids in honey, iced tea and canned coffee drinks.

Matched MeSH terms: Ice
A comparison between ice and salt storages on bacteriological quality of Asian seabass (Lates calcarifer)

Rahman MM, Nasrun M, Hossain MY, Aa'zamuddin M

Pak J Biol Sci, 2012 Jun 15;15(12):583-8.
PMID: 24191620

The study compares the bacteriological quality on Asian seabass (Lates calcarifer) between ice and salt storage methods. The main objectives of the study were to identify different bacteria constituents and quantitative bacterial load in Asian seabass when preserved with ice and sea salt. For the purpose of this study, Asian seabass was stored in two different conditions of ice-chilled and salted for 2 days. All fish samples were analyzed by performing bacteriological analysis and the isolated bacteria were identified by using API identification system. In case of the quantity of bacteria in the flesh, Chilling and salting had no significant difference to the quantity of bacteria on fish flesh. As for the skin, salt-preserved fish showed higher quantity of bacteria than ice-preserved fish. Acinetobacter baumannii and Pseudomonas fluorescens had been identified from skin sample of ice-chilled fish. Besides P. fluorescens and A. baumannii other isolates identified include Vibrio and Myxobacteria. All bacteria were cocci-shaped except a few bacilli. In term of bacteria number and morphological characteristics, ice-chilled preserved fish was better than salt preserved fish. Overall, less number of bacteria was observed in both ice-chilled and sea salt preserved fish. The result of this study indicated that the quick preservation is a very important factor to control bacterial load in the preserved fish.

Matched MeSH terms: Ice
Fulltext Acne vulgaris and its association with dietary intake: a Malaysian perspective

Suppiah TSS, Sundram TKM, Tan ESS, Lee CK, Bustami NA, Tan CK

Asia Pac J Clin Nutr, 2018 10 3;27(5):1141-1145.
PMID: 30272862 DOI: 10.6133/apjcn.072018.01

BACKGROUND AND OBJECTIVES: Acne vulgaris is a common skin condition among adolescents and young adults. Its relationship with the dietary intake is highly debatable and equivocal. This study aimed to identify the association between acne vulgaris and dietary intake among Malaysians.
METHODS AND STUDY DESIGN: A case-control study was conducted involving 57 acne vulgaris patients and 57 age-, gender- and ethnicity-matched controls. All participants were aged 14 and above. The Comprehensive Acne Severity Scale (CASS) was used to categorise patients (grades 2 to 5) and controls (grades 0 to 1). Information such as the demographics, family history, smoking habits and dietary intake were collected using a self-administered questionnaire.
RESULTS: In the patient arm, the gender ratio of male to female was 1.5:1. 43 patients (75.4%) had a family history of acne vulgaris. No significant association was found for acne in patients with a history of smoking. Milk consumption was significantly higher in patients (63.2%, n=36) versus controls (43.9%, n=25), (OR=2.19, p<0.05). In addition, chocolate consumption was also significantly higher in patients (43.9%, n=25) versus controls (24.6%, n=14), (OR=2.4, p<0.05). No significant association was found with the intakes of sweets, potatoes, chips, nuts, yoghurt, ice-cream or carbonated drinks.
CONCLUSIONS: Dietary intake of milk and chocolate may play a role in acne vulgaris. Prospective cohort and intervention studies are recommended to explore whether a causal relationship might obtain.

Matched MeSH terms: Ice Cream
Fulltext Solution structures, dynamics, and ice growth inhibitory activity of peptide fragments derived from an antarctic yeast protein

Shah SH, Kar RK, Asmawi AA, Rahman MB, Murad AM, Mahadi NM, et al.

PLoS One, 2012;7(11):e49788.
PMID: 23209600 DOI: 10.1371/journal.pone.0049788

Exotic functions of antifreeze proteins (AFP) and antifreeze glycopeptides (AFGP) have recently been attracted with much interest to develop them as commercial products. AFPs and AFGPs inhibit ice crystal growth by lowering the water freezing point without changing the water melting point. Our group isolated the Antarctic yeast Glaciozyma antarctica that expresses antifreeze protein to assist it in its survival mechanism at sub-zero temperatures. The protein is unique and novel, indicated by its low sequence homology compared to those of other AFPs. We explore the structure-function relationship of G. antarctica AFP using various approaches ranging from protein structure prediction, peptide design and antifreeze activity assays, nuclear magnetic resonance (NMR) studies and molecular dynamics simulation. The predicted secondary structure of G. antarctica AFP shows several α-helices, assumed to be responsible for its antifreeze activity. We designed several peptide fragments derived from the amino acid sequences of α-helical regions of the parent AFP and they also showed substantial antifreeze activities, below that of the original AFP. The relationship between peptide structure and activity was explored by NMR spectroscopy and molecular dynamics simulation. NMR results show that the antifreeze activity of the peptides correlates with their helicity and geometrical straightforwardness. Furthermore, molecular dynamics simulation also suggests that the activity of the designed peptides can be explained in terms of the structural rigidity/flexibility, i.e., the most active peptide demonstrates higher structural stability, lower flexibility than that of the other peptides with lower activities, and of lower rigidity. This report represents the first detailed report of downsizing a yeast AFP into its peptide fragments with measurable antifreeze activities.

Matched MeSH terms: Ice
Functional and structural analyses of an expansin-like protein from the antarctic yeast Glaciozyma antarctica PI12 reveal strategies of nutrient scavenging in the sea ice environment

Mohamad Nor N, Hashim NHF, Quay DHX, Mahadi NM, Illias RM, Abu Bakar FD, et al.

Int J Biol Macromol, 2020 Feb 01;144:231-241.
PMID: 31843615 DOI: 10.1016/j.ijbiomac.2019.12.099

Genome data mining of the Antarctic yeast, Glaciozyma antarctica PI12 revealed an expansin-like protein encoding sequence (GaEXLX1). The GaEXLX1 protein is 24.8 kDa with a high alkaline pI of 9.81. Homology modeling of GaEXLX1 showed complete D1 and D2 domains of a conventional expansin. The protein exhibited 36% sequence similarity to Clavibacter michiganensis EXLX1 (PDB: 4JCW). Subsequently, a recombinant GaEXLX1 protein was produced using Escherichia coli expression system. Incubation with Avicel, filter paper and cotton fiber showed that the protein can disrupt the surface of crystalline and pure cellulose, suggesting a cell wall modification activity usually exhibited by expansin-like proteins. Binding assays displayed that GaEXLX1 can bind to polymeric substrates, including those postulated to be present in the sea ice ecosystem such as crab chitin and moss lichenan. GaEXLX1 may assist in the recognition and loosening of these substrates in the sea ice prior to hydrolysis by other extracellular enzymes. Similar loosening mechanism to classical expansin-like protein has been postulated for this psychrophilic protein based on several conserved residues of GaEXLX1 involved in binding interaction identified by docking analyses.

Matched MeSH terms: Ice Cover
Fulltext Forest contraction in north equatorial Southeast Asia during the Last Glacial Period

Wurster CM, Bird MI, Bull ID, Creed F, Bryant C, Dungait JA, et al.

Proc Natl Acad Sci U S A, 2010 Aug 31;107(35):15508-11.
PMID: 20660748 DOI: 10.1073/pnas.1005507107

Today, insular Southeast Asia is important for both its remarkably rich biodiversity and globally significant roles in atmospheric and oceanic circulation. Despite the fundamental importance of environmental history for diversity and conservation, there is little primary evidence concerning the nature of vegetation in north equatorial Southeast Asia during the Last Glacial Period (LGP). As a result, even the general distribution of vegetation during the Last Glacial Maximum is debated. Here we show, using the stable carbon isotope composition of ancient cave guano profiles, that there was a substantial forest contraction during the LGP on both peninsular Malaysia and Palawan, while rainforest was maintained in northern Borneo. These results directly support rainforest "refugia" hypotheses and provide evidence that environmental barriers likely reduced genetic mixing between Borneo and Sumatra flora and fauna. Moreover, it sheds light on possible early human dispersal events.

Matched MeSH terms: Ice Cover
Oral Cryotherapy: Prevention of Oral Mucositis and Pain Among Patients With Colorectal Cancer Undergoing Chemotherapy

Idayu Mat Nawi R, Lei Chui P, Wan Ishak WZ, Hsien Chan CM

Clin J Oncol Nurs, 2018 10 01;22(5):555-560.
PMID: 30239519 DOI: 10.1188/18.CJON.555-560

BACKGROUND: Evidence remains mixed on the benefits of oral cryotherapy in the prevention of oral mucositis and pain associated with fluorouracil-based chemotherapy.
OBJECTIVES: The intent of this article is to evaluate the effect of oral cryotherapy on the prevention of oral mucositis and pain among patients with colorectal cancer undergoing fluorouracil-based chemotherapy.
METHODS: Using an experimental study design, the authors randomly assigned 80 patients to either the intervention (n = 40) or usual care group (n = 40). Intervention group participants received oral cryotherapy in the form of ice chips held in their mouths during chemotherapy infusion. Both groups used sodium bicarbonate mouthwash postchemotherapy until the next cycle.
FINDINGS: In the usual care group, most participants reported grade 2 (moderate to life-threatening) or greater mucositis. Pain associated with mucositis was lower using oral cryotherapy, with the majority of participants in the intervention group reporting no pain.

Matched MeSH terms: Ice