KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Settings

Author: search.filters.author.Pilasombut, KomkhaeSubject: search.filters.subject.Antioxidant

Search Results

Now showing 1 - 2 of 2
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Siamese neem tree as a natural preservative: Chemical profile, antioxidant properties, and antibacterial efficacy against foodborne pathogens and spoilage bacteria
    (2025-03-01)
    Puttongsiri, Tongchai
    ;
    Manichart, Nutcha
    ;
    Teerarak, Montinee
    ;
    Sikhao, Potjana
    ;
    Somala, Naphat
    The objective of the present study was to investigate the effect of various ethanol in water solvent systems (0, 25, 50, 75 and 100 % v/v) on the extraction crude yield, total phenolic content, total flavonoid content, and chemical profile of Azadirachta indica (Siamese neem tree) leaf extracts. In addition, the antioxidant and antimicrobial properties were investigated using in vitro assays. Crude yield was highest for the water extract (5.78 g/100 g DW) and decreased with increased ethanol. Total phenolic and flavonoid contents were highest in the 75 % ethanol extract (26.95 mg GAE/g crude and 23.73 mg QE/g crude, respectively). GC-MS analysis of the 75 % ethanol extract revealed 33 bioactive compounds, accounting for 96.33 % of the total area. Significant components included benzene, 1,4-bis(phenylmethyl)- (15.05 %), and naphthalene, 1,6-dimethyl- (10.98 %); also present were sterols, fatty acids, hydrocarbons, aromatic, and heterocyclic compounds, indicating a complex chemical profile. In antioxidant assays, the 75 % ethanol extract revealed the highest DPPH radical scavenging activity (IC<inf>50</inf>: 143.03 mg/L), reducing power (IC<inf>50</inf>: 378.69 mg/L), and lipid peroxidation (IC<inf>50</inf>: 526.25 mg/L). However, the absolute ethanol extract exhibited both the highest metal chelating activity (IC<inf>50</inf>: 382.60 mg/L) and the strongest antimicrobial activity, inhibiting all 11 tested foodborne pathogenic and spoilage bacteria. The lowest minimum inhibitory concentration (MIC) of 25 mg/mL was observed for Staphylococcus aureus, Aeromonas hydrophila, Pseudomonas fluorescens, Latilactobacillus sakei, Streptococcus sp., and Lactococcus cremoris, with inhibition zone diameters of 27.21, 28.79, 28.19, 17.60, 15.09 and 11.20 mm, respectively. Similarly, the lowest minimum bactericidal concentration (MBC) of 25 mg/mL was obtained for S. aureus and L. sakei, indicating potent antibacterial effects against these species. Future studies should include direct comparative analyses of neem extracts and synthetic preservatives to evaluate further their relative efficacy and applicability in real-world food systems.
  • Loading...
    Thumbnail Image
    Some of the metrics are blocked by your 
    consent settings
    Item type:Publication,
    Potential antioxidant and lipid peroxidation inhibition of Phyllanthus acidus leaf extract in minced pork
    (2017-09-01)
    Nguyen, Tuyen Thi Kim
    ;
    Laosinwattana, Chamroon
    ;
    Teerarak, Montinee
    ;
    Pilasombut, Komkhae
    Objective: This study investigated the effect of extraction solvents on antioxidant bio-active compounds as well as potential antioxidant and lipid peroxidation inhibition of Phyllanthus acidus (P. acidus) leaf extract in minced pork. Methods: The effect of various solvent systems of water, 25%, 50%, 75% (v/v) ethanol in water and absolute ethanol on the extraction crude yield, total phenolic content, total flavonoid content and in vitro antioxidant activities of P. acidus leaves was determined. In addition, antioxidant activities of the addition of crude extract from P. aciuds leaves at 2.5 and 5 g/kg in minced pork on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical cation decolorization, reducing power and inhibition of lipid peroxidation (thiobarbituric acid reactive substances; TBARS) were determined. Moreover, sensory evaluation of the samples was undertaken by using a 7-point hedonic scale. Results: The results showed that the highest crude yield (2.8 g/100 g dry weight) was obtained from water which also had the highest recovery yield for total phenolic content, total flavonoid content and the strongest antioxidant activity. The addition of crude water extract from P. acidus leaves was more effective in retarding lipid peroxidation and higher antioxidant activity than control and butylated hydroxytoluene in minced pork. In particular, the samples containing P. acidus extract had no significant effect on the sensory scores of overall appearance, color, odor, texture, flavor, and overall acceptability compared to the control. Conclusion: Water solvent was an optimally appropriate solvent for P. acidus leaf extraction because of its ability to yield the highest amount of bio-active compounds and in vitro antioxidant property. Particularly, P. acidus crude water extract also strongly expressed the capacity to retard lipid oxidation, radical scavenging, radical cation decolorization and reducing power in minced pork. The results of this study indicated that P. acidus leaf extract could be used as natural antioxidant in the pork industry.