Highest Total Phenolic Content Research Articles

Untargeted metabolomics reveals the mechanism of ultrasound combined with L-cysteine treatment inhibiting the browning of fresh-cut potatoes

Freshly cut potatoes tend to brown during processing and preservation, which is an important issue worldwide. Ultrasound (US) combined with L-cysteine (L-Cys) treatment (US-L-Cys) has been reported to inhibit the browning of fresh-cut potatoes in our laboratory. However, the underlying mechanism remains to be elucidated. Untargeted metabolomics, a popular high-throughput technique, has been used to investigate the biochemical changes that are closely associated with the browning of fresh-cut fruits and vegetables. The present study investigated the effect of US-L-Cys treatment on the browning index (BI), related enzyme activities, total phenolic content, antioxidant capacity, malondialdehyde (MDA) content, and relative electrical conductivity of fresh-cut potatoes during 6-d storage. Metabolomics was used to compare the metabolites of US-L-Cys-treated and control samples on days 0 and 6. The results showed that US-L-Cys treatment reduced BI; decreased polyphenol oxidase, peroxidase, and phenylalanine ammonia-lyase activities; maintained high total phenolic content; increased antioxidant capacity; and decreased MDA content and relative electrical conductivity in fresh-cut potatoes during storage. Metabolomic analysis revealed that tyrosine and amino acid metabolisms were enriched. Higher levels of alanine and lower levels of dopamine were observed in US-L-Cys-treated samples compared with control samples. Therefore, depressed tyrosine and activated alanine metabolisms may be involved in the mechanism through which US-L-Cys inhibits the enzymatic browning of fresh-cut potatoes during storage.

Investigation of chemical constituents, antioxidant, anti-inflammatory and nutritional properties of oil of Persea americana (Avocado) seeds

This study investigated the phytochemical composition, in vitro antioxidant, and anti-inflammatory properties of the oil of Persea americana seeds (OPAS). The flavonoid and total phenol compositions were quantified using standard colorimetric methods; the antioxidant potentials of the seed were determined using 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays, while the anti-inflammatory potentials were investigated using membrane stabilization (hypotonicity) and heat-induced hemolysis of human red blood cells (HRBC) assays. In addition, gas chromatography-mass spectrometry (GC–MS) analysis was employed to characterize the phytochemicals in the oil. The nutritional indices (atherogenic index, thrombogenic index, and polyene index) were also calculated. Results indicated high total phenolic and flavonoid contents (25.78 ± 0.68 mg gallic acid equivalent per gram (GAE/g) and 72.69 ± 1.11 mg quercetin equivalent per 100 mg (QE/100 mg), respectively). The oil of P. americana seeds showed dose-dependent (25–400 μg/mL) antioxidant and anti-inflammatory activities compared to the standard agents used (olive oil and ascorbic acid). The GC–MS analysis showed the presence of fatty acids including tetradecanoic acid (33.33 %), 9, 12-octadecadienoic acid, methyl ester (20.12 %), n-hexadecenoic acid (7.07 %), and oleic acid (11.60 %). Nutritional indices showed that OPAS had a very low polyunsaturated/saturated (PUFA/SFA) ratio (0.45), hypocholesterolemic/hypercholesterolemic (0.26), but high atherogenicity index (IA) (4.13) and thrombogenicity index IT (9.47) values. The beneficial potentials of OPAS revealed in this study suggest that it can be harnessed as a potent antioxidant and anti-inflammatory agent in phytomedicine. However, the nutritional quality and culinary suitability of OPAS with different oils require further study.

Methyl jasmonate advances fruit ripening, colour development, and improves antioxidant quality of ‘Yoho’ and ‘Jiro’ persimmon

Methyl jasmonate (MJ) has potential to regulate fruit ripening and quality. ‘Yoho’ and ‘Jiro’ persimmons were sprayed with MJ (0, 2, 4, and 6 mM), four weeks before anticipated harvest to evaluate its effects on fruit colour and bioactive compounds. Preharvest MJ application significantly improved fruit colour with increased a*, b*, chroma, and colour index. The MJ 6 mM application had significantly enhanced soluble solids content (SSC), reduced total chlorophyll content in peel and pulp, and soluble and total tannins in persimmons. MJ treatments exhibited higher contents of total phenolics, flavonoids, carotenoids, and antioxidant activities. Additionally, MJ treatments enhanced the activities of shikimate dehydrogenase (SKDH), phenylalanine ammonia-lyase (PAL), catalase (CAT), superoxide dismutase (SOD), peroxidase (POD) and lipoxygenase (LOX) enzymes. Overall, pre-harvest MJ application at 6 mM four weeks before anticipated harvest could be useful for advancing colour and improving bioactive compounds in ‘Yoho’ and ‘Jiro’ persimmons.

In vitro antioxidant and antibacterial activities of aqueous extract of microalgae strain MRB-1, MRB-2, and MRB-3

Abstract The awareness growth of human health encourages market demand of functional food. Microalgae are promoted as natural resources for functional food, food additives and food preservatives, considering their metabolites and nutrient-rich components with diverse pharmacological activities. This study aims to evaluate the phytochemicals, antioxidant, and antibacterial activities of aqueous extracts of microalgae strain MRB-1, MRB-2, and MRB-3. The morphological surface of microalgae cells was analyzed using Scanning Electron Microscopy (SEM). The metabolites of the extract were conducted using Liquid Chromatography-High Resolution Mass Spectroscopy (LC-HRMS) with positive and negative ion modes. In addition, the antioxidant activity was evaluated using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and the antibacterial activity was assessed using the agar disk-diffusion method against gram-positive bacteria (Staphylococcus aureus ATCC 25923) and gram-negative bacteria (Escherichia coli ATCC 8739). The total phenolic contents (TPC) of the extract was determined using the Folin-Ciocalteu assay. The result revealed that the aqueous extract of microalgae strain MRB-1 had the highest scavenging activity toward DPPH radicals with a value of 24.33±1.44% at 0.8 mg/mL. This data was in accordance with the TPC of the extract, whereas the highest TPC was also obtained from strain MRB-1 extract (17.73±0.64 mg GAE/g extract). Meanwhile, the MRB-2 extract had the highest inhibition activity against S. aureus, with a value of 11.78±2.06 mm at 18 mg/mL. The results of this study indicated that microalgae from the peatlands potentially benefit to human health as a natural antioxidant and antibacterial source.

Effect of aqueous extraction method on total water-soluble polysaccharides content and phytochemical properties of white oyster mushroom (Pleurotus ostreatus)

Abstract White oyster mushroom (Pleurotus ostreatus) is an important raw material for nutraceuticals because it contains various bioactive substances, including polysaccharides, vitamins, phenolic acids, terpenoids, and sterols. P. ostreatus mushroom polysaccharides possess diverse biological activities (antioxidant, hyperglycemic effects, and immunomodulatory). The extraction process impacts the yield, affecting the biological function of natural active ingredients. In this study, aqueous extraction methods, i.e., ultrasonic-assisted extraction (UAE), microwave-assisted extraction (MAE), and kinetic-assisted hot extraction (KAHE), were applied to investigate the impact of extraction methods on polysaccharides crude extract from the fruiting bodies of P. ostreatus mushroom and their phytochemical properties. Water-soluble polysaccharides content, total polyphenolic content, total terpenoid content, and antioxidant level were analyzed using the spectrophotometric method by phenol-sulfuric acid, Follin-Ciocalteau’s reagent, vanillin-perchloric acid, and 1,2-diphenyl-2-picrylhydrazyl (DPPH) scavenging assay, respectively. After the extraction process, the morphological alterations on the surface of mushroom residues were observed using Scanning Electron Microscopy (SEM). The investigation has shown that aqueous extraction methods significantly affect the yields of polysaccharides crude extract and other phytochemical properties, i.e., total phenolic content, terpenoid content, and the DPPH free radical scavenging activity. The sample from MAE had the highest total water-soluble polysaccharide content (61,73±1,35% w/w DW) and the highest total phenolic content (3,44±0,75 %w/w DW). MAE method has the best potential and efficiency compared to UAE and KAHE for extracting polysaccharides while maintaining their phytochemical properties.

Effect of Drying Methods on the Phenolic Compounds and Antioxidant Activity of Leaf of Agarwood (Aquilaria malaccensis Lam.)

This study is a preliminary analysis of the effect of various drying techniques on the phenolic components and antioxidant capability for developing protocols to produce herbal products from Aquilaria malaccensis. Aquilaria leaf samples (ALS) were subjected to different drying methods such as air-dry (AD), oven-dry (OD), sun-dry (SD), drying with food dehydrator (DD), and a combination of air-dry and use of dehydrator (CAD). After drying and grinding, samples were infused with hot water. Different parameters such as water extract, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activities were evaluated. Results revealed that there was no significant difference in the water extract of ALS among different methods. High TPC concentrations were recorded at SD, OD, and DD. The highest TFC concentration was observed in CAD and was significantly different among the drying treatments. Further, using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, the dehydrated-ALS possessed the highest antioxidant capacity of 524.33 ± 0.04 μmol TEAC/g among the treated samples. Meanwhile, based on the cupric reducing antioxidant capacity (CUPRAC) assay, the highest antioxidant activity among the treatments was sundried-ALS with a value of 391.70 ± 0.037 μmol TEAC/g sample. Based on these findings, the drying methods – particularly utilizing a dehydrator, sun- drying, or a combination of air-drying and using a dehydrator – all preserve the phenolics and antioxidant properties of A. malaccensis. Overall, the drying process significantly influenced the chemical characteristics and antioxidant activity of A. malaccensis tea.

Pengaruh Lama Perebusan Kedelai (Glycine max. L) Menggunakan Autoclave Terhadap Senyawa Fitokimia Tempe

Tempe is a traditional Indonesian food, a processed product made from soybeans which is formed from the Rhizopus Sp type mold, especially from the R. oligosporus species through a fermentation process. The tempeh production process needs to be improved in terms of time efficiency, cost, workmanship effectiveness and nutrition. This improvement can be done by boiling the soybeans in an autoclave. Soybeans contain antioxidant compounds in the form of isoflavones, tocopherol and ascorbate. Antioxidants are really needed by the body as an antidote to free radicals because they work by donating one electron to compounds that are oxidants so that the negative impact of oxidants can be inhibited. The aim of this research was to determine the effect of boiling time for soybeans (Glycine max L.) in an autoclave on phytochemical compounds (total polyphenols, total flavonoids and antioxidants) as well as the sensory properties (color and compactness) of soybean tempeh. This research method uses a non-factorial experimental design prepared with RAL (Completely Randomized Design) which consists of 1 factor, namely the length of boiling soybeans in an autoclave with 4 treatment levels P1 (5 minutes), P2 (10 minutes), P3 (20 minutes), P4 (30 minutes) and each treatment was repeated 3 times. The results showed that the highest total phenolic content and total flavonoid content were obtained from soybean tempeh with soybean tempeh treatment in an autoclave for 5 minutes, namely 5.33 mgGAE/g and 0.121 mgQE/g, while the highest antioxidant activity was obtained from soybean tempeh with boiling treatment. soya bean. in an autoclave for 30 minutes, namely 11.32%

PHYTOCHEMICAL AND ANTIOXIDANT ASSESSMENT OF ALLIUM HYPSISTUM, ALLIUM PRZEWALSKIANUM AND ALLIUM WALLICHII

High altitude plants are tremendously used mostly as food and traditional medicine for their role on prevention and treatment of several diseases. Thus, this study focused on comprehensive analysis of the phyto-constituents and the antioxidant activities of three plants; .Allium hypsistum, Allium przewalskanium, and Allium wallichii. Upon analysis, the phytoconstituents such as alkaloids, terpenoids, steroidal compounds, glycosides, carbohydrates and aminoacids were identified in ethanolic, n-hexane and aqueous extracts of the plant whereas saponins and quinones were not detected at all. Other photochemicals like flavonoids, phenolic compound, and tannins were found in ethanolic and water extracts but not in the n-hexane extract. The antioxidant activities were evaluated using total phenolic content (TPC) and 2, 2-diphenyl -1-picrylhydrazyl (DPPH) radical scavenging assay. TPC was assayed by Folin-Ciocalteu reagent method. The phenolic compounds were present in all three types of extracts; however, the highest TPC was estimated only in ethanolic extract of A. hypsistum i.e. 172mgGAE/100g. Among the extracts, ethanol extract of A. hypsistum showed the highest DPPH free radical scavenging property 59.44 %RSA (radical scavenging activity) when compared to the reference molecule ascorbic acid that had 75.11 %RSA. Among selected three plants, both TPC and %RSA revealing the antioxidant activities were found to be higher in A. hypsistum followed by A. prsewalskanium and A. wallichii. Furthermore, relationship between TPC and DPPH activity (%RSA) were established and found weak to strong correlation but they were statistical non-significant. From this study, such findings may help to know chemical constituents and medicinal values of Allium species which may lead to develop new phytomedicines and use of these plants in herbal therapy.

Characterization and screening of cotton (Gossypium hirsutum L.) germplasm for leafhopper (Amrasca biguttula biguttula (Ishida)) resistance

BackgroundCotton (Gossypium hirsutum L.) is one of the most significant fibre and cash crops and plays an important role in Indian industrial and agricultural economies. However, over the years quantity and quality have been hampered by the pest leafhopper. Leafhopper alone has been shown to cause yield losses of up to 40%. In this study, screening and evaluation were performed to identify and categorize 100 cotton genotypes along with 5 checks as resistant, moderately resistant, sensitive and highly sensitive to leafhoppers.ResultsA total of hundred genotypes were evaluated along with five checks for leafhopper resistance. Based on the screening results, a total of 19 genotypes were resistant to leafhoppers, which was on par with the findings of the check KC 3. The contents of total soluble sugar, total soluble protein, and total free amino acids were significantly positively correlated with the mean grade, whereas total phenols content and trichome density were significantly negatively correlated with the susceptibility grade. However, based on screening and biochemical analysis, the genotypes KC 2, JR-23, Samaru-26-T, D 4, TCH 1728, RS 253, and B-61-1862 exhibited high resistance to leafhopper.ConclusionAccording to the findings of this study, choosing genotypes with high total phenolics content together with high trichome density and low contents of total soluble sugar, total soluble protein, and free amino acids may aid in the development of resistant genotypes.

Varietal Susceptibility of Olive to Pseudomonas savastanoi pv. savastanoi and the Antibacterial Potential of Plant-Based Agents.

Olive knot disease, caused by the bacterium Pseudomonas savastanoi pv. savastanoi, causes great damage in olive orchards. While control measures of P. savastanoi pv. savastanoi in olive orchards primarily rely on pruning and copper-based treatments, the use of antibiotics as bactericidal preparations in agriculture is limited and highly restricted. However, plants are naturally endowed with protective molecules, such as phenolic compounds, which defend them against herbivores, insects, and microorganisms. This research aimed to test the virulence of five strains of P. savastanoi pv. savastanoi isolated from different growing regions and olive varieties, and to examine whether there is a difference in plant susceptibility based on the variety. An additional goal was to test the antimicrobial activity of olive mill wastewater, known for its high content of phenolic compounds, and aqueous garlic hydrolysate, as well as to compare them with a commercial copper-based product, pure hydroxytyrosol, and a standard antibiotic as references. Analysis of knot characteristics showed variations in the virulence of the P. savastanoi pv. savastanoi strains, with the highest virulence being observed for the strain I7L and the lowest virulence for the strain B45C-PR. The olive cultivar Rosinjola displayed higher susceptibility compared to Frantoio, Buža, and Leccino, while cv. Istarska bjelica exhibited the least susceptibility compared to the other investigated olive cultivars. In an attempt to explore alternative solutions for disease control, in vitro tests revealed that the phenol HTyr, GE, and the wastewater with the highest total phenolic content (cv. Istarska bjelica) possess the highest antibacterial activity. This supports the role of polyphenols in host defense, aligning with previous field observations of lower susceptibility of cv. Istarska bjelica to olive knot disease. These findings highlight the complex nature of olive knot interactions with bacterial strains and olive cultivars, simultaneously accentuating and underscoring the importance of considering the host's defenses as well as bacterial virulence in disease management strategies.

Polyphenolic Profiling and Antioxidant Activity in Berry Extracts of Pyracantha Wild Varieties from the Mediterranean Region.

Pyracantha is a genus of wild perennial shrubs native in an area extending from Southwest Europe to Southeast Asia, and it is used in traditional medicine for the diuretic, cardiac, and tonic properties of its fruits, which can also be cooked to make jellies, jams, and sauces. This work aims to study and compare the antioxidant activity and the phenolic and anthocyanin composition of three varieties of Pyracantha coccinea: Red Column (PCR), Orange Glow (PCO), and Soleil d'Or (PCS), and one of Pyracantha angustifolia: Orange glow (PAO), collected from the spontaneous flora of the Mediterranean region (Southern Italy). Two different extraction processes were tested using methanol and an aqueous methanol solution (80% MeOH) to evaluate the polyphenolic content and antioxidant activity of freeze-dried berries. The highest total phenolic content was found in PCR and PAO berries (174.21 ± 0.149 and 168.01 ± 0.691 mg of gallic acid equivalent per gram of dry matter, respectively) extracted with an aqueous methanol solution (80% MeOH). Polyphenolic extracts analyzed by HPLC-DAD-ESI/MS confirmed the presence of rutin, quercetin hexose, neoeriocitrin, procyanidin B, and resveratrol. Moreover, the total antioxidant activity of the berries' extracts was measured by comparing two different spectrophotometric methods (ABTS and DPPH), showing that the varieties with the highest total phenolic content, PCR and PAO, also had the highest scavenging activity. Finally, a suitable extraction process was chosen for the evaluation of the anthocyanins' composition of all frozen berries, and in all MS spectra of Pyracantha varieties, two ionic species at 449 m/z attributable to two cyanidin derivatives were found.

The Impact of Chlorella vulgaris Fortification on the Nutritional Composition and Quality Characteristics of Beef Burgers.

Chlorella vulgaris (C.V) is known for its high protein and nutrient contents and has been touted as a potential functional ingredient in food products. For this study, beef burgers were formulated with varying levels of Chlorella vulgaris fortification (0%, 0.5%, 1%, and 1.5% by weight). The nutritional composition, including proximate analysis and mineral content, was determined for each treatment group. The quality characteristics evaluated included thiobarbituric acid (TBA), total volatile base nitrogen (TVBN), pH, and total acidity. The study included extracting the active substances from Chlorella vulgaris using three solvents, 50% ethanol, 95% ethanol, and water, to evaluate the effect on the antimicrobial and antioxidant activity. The results showed that the water extract had the highest total phenolic content (183.5 mg gallic acid equivalent per gram) and the highest flavonoid content (54 mg quercetin per gram). The aqueous extract had the highest content of total antioxidants, followed by the 95% ethanol and 50% ethanol extracts. Meanwhile, the 50% ethanol extract showed the best antimicrobial activity, while the aqueous extract had less of an effect on Gram-positive bacteria and no effect on E. coli. For the burger treatments, at the end of the storage period, it was observed that the microbial load of the treatments decreased compared to the control, and there was a high stability in the total volatile base nitrogen (TVBN) values for the treatments compared to the control, reaching a value of 22.4 at month 5, which is well above the acceptable limit, indicating spoilage. The pH values were higher for all of the treatments, with a lower total acidity for all of the treatments compared to the control. In conclusion, utilizing Chlorella vulgaris algae as a natural preservative to extend the freshness of burgers is a sustainable and innovative approach to food preservation. By harnessing the power of this green superfood, we not only enhance the shelf life of our food products but also contribute to a healthier and more environmentally friendly food industry.

Evaluation of Hedera species as herbal medicine raw materials

This study aimed to evaluate the potential of Hedera colchica as an alternative to Hedera helix species for the treatment of mild inflammatory conditions of the upper respiratory tract and chronic inflammatory bronchial diseases. The H. colchica extract with the highest saponin content (C3S; 468.19 ± 16.01 mg HE/g dry weight) and the extract with the highest total phenol content (C1F; 108.60 ± 5.61 mg GAE/g dry weight). Chemical analysis and standardisation of the extract with the highest selective COX-2 inhibitory effect was performed using the LC-MS/MS technique. It was determined that the substances found in the highest ratio in the C1F extract were quinic acid (45.909 µg/g extract) and hesperidin (37.077 µg/g extract). As a result, secondary metabolites, in addition to saponins, found in Hedera species may also contribute to the extract’s effectiveness, more potent extracts can be obtained compared to the total extract-containing preparations available in the market.

Characterization of the Byproducts of Myrciaria dubia and Psidium guajava and Optimization of the Extraction of Their Bioactive Compounds by Ultrasound-Assisted Extraction and Mechanical Agitation

The food industry generates considerable byproducts that are often discarded and have high contents of usable bioactive compounds. The aim of this study was to characterize the byproducts of camu-camu (Myrciaria dubia) (shell and seed) and guava (Psidium guajava) (shell) production. The extraction and stabilization of the bioactive compounds of camu-camu and guava were also optimized. The variables of ultrasound-assisted extraction (UAE) (shaking time, sonication time and volume–mass ratio) and mechanical shaking-based extraction (MS) (shaking speed, volume–mass ratio and shaking time) were optimized with the surface response method and a Box–Behnken design. The responses studied were total phenolic content (TPC) and antioxidant capacity (AC) evaluated by the degradation of the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) technique and by the ferric reducing antioxidant powder (FRAP) test. For ultrasound-assisted extraction, the optimal sonication time was 15 min for both the M. dubia and P. guajava shells, and the volume–mass ratios were 50 mL/g for the M. dubia shell and 60 mL/g for the P. guajava shell. However, for M. dubia seeds, there was an agitation time of 3 h, a sonication time of 4.4 min and a volume–mass ratio of 50 mL/g. During extraction by mechanical stirring, the optimal volume–mass ratio for both M. dubia seeds and P. guajava shells was 60 mL/g, while for M. dubia shells, it was 50 mL/g. For the shells and seeds of M. dubia and the shells of P. guajava, the optimal stirring times were 2, 6.4 and 7.7 h, respectively, and the optimal stirring speeds were 172.2, 250 and 256.3 rpm, respectively. Under these optimal conditions, the highest total phenolic content (TPC) results were acquired from the cuma-cuma peel (CCP) extract (26.2 mg gallic acid equivalent (GAE)/g sample) obtained by UAE and from guava peel (GP) extract (27.9 mg GAE/g sample) obtained by MS. The optimized models showed that MS was more efficient than UAE for obtaining bioactive compounds from byproducts of M. dubia and P. guajava. However, UAE required much shorter extraction times than MS. In conclusion, the models obtained for the recovery of bioactive compounds could be applied in large-scale industries to fully exploit the byproducts studied.

Repurposing Castanea sativa Spiny Burr By-Products Extract as a Potentially Effective Anti-Inflammatory Agent for Novel Future Biotechnological Applications.

The concept of a "circular bioeconomy" holds great promise for the health, cosmetic, and nutrition sectors by re-using Castanea sativa (Mill.) by-products. This sustainable resource is rich in bioactive secondary metabolites with antioxidant and anti-inflammatory properties. By transforming these by-products into high-value products for human health, we can promote sustainable economic growth and reduce the environmental impact of traditional waste disposal, adding value to previously underutilized resources. In the present study, we investigated the antioxidant capacity, phytochemical composition, and in vitro antioxidant and anti-inflammatory activity of C. sativa burr (CSB) aqueous extract. The spectrophotometric study revealed high total phenolic content (TPC) values with significant antioxidant and anti-radical properties. Using UPLC-MS/MS techniques, the phytochemical investigation identified 56 metabolites, confirming the presence of phenolic compounds in CSBs. In addition, CSBs significantly downregulated pro-inflammatory mediators in LPS-stimulated RAW 264.7 macrophage cells without significant cell toxicity. Lastly, in silico studies pinpointed three kinases from RAW 264.7 cells as binding partners with ellagic acid, the predominant compound found in our extract. These findings strongly advocate for the recycling and valorization of C. sativa by-products, challenging their conventional classification as mere "waste".

Phytotoxicity of phenolic compounds of Pistacia vera leaves and its potential use as bioherbicide

In recent years, the intensive and uncontrolled use of synthetic herbicides has resulted in severe soil and water contamination, inducing herbicide resistance and damage to living organisms. The aim of this work was to study the potential bioherbicidal effect of extracts obtained from pistachio leaves. Aqueous extracts (3, 6, 12, and 25%) were prepared and their inhibitory effect on three weed species (Lolium rigidum, Solanum nigrum, and Lactuca serriola) and four crops (maize cv. Celestquatro, barley cv. Yurico, wheat cv. Rimbaud, and lentil cv. Castellana) was studied. Germination bioassays in Petri dishes and in vivo tests on organic and inert substrates were carried out with the extracts. In addition, the phenolic compounds present in the extracts were analysed and germination bioassays of the pure and individual compounds identified were performed. The results showed that the extracts caused a significant suppression of germination in weeds, being more remarkable for broadleaf species. For crops, no adverse effects on germination rates were observed. Inert substrate experiments showed a stronger inhibitory influence on weed germination, whereas organic substrate did not. Autumn leaf extracts showed a higher content of total phenols. Component analysis and bioassay showed that gallic acid, catechin, myricetin, and rutin were identified as individual phenolic compounds in the extracts and demonstrated some allelopathic activity. It may be concluded that pistachio leaf extracts had season-varied allelopathic activity, which is attributed to the combined bioactivity with those individual phenolic compounds.

Nutritional and bioactive compound analysis of mangosteen fruit in hill and flat land plantations, during both the season and off-season, in provinces along the Gulf of Thailand and the Andaman Sea

This study examined the nutritional, physicochemical, and bioactive compounds in mangosteen grown in southern Thailand from 2022 to 2024, encompassing hilly areas (Nakhon Si Thammarat range, Tenasserim range) and flat lands during both the fruit season and off-season. The influence of coastal regions (Gulf of Thailand and Andaman coast) on mangosteen nutrition was explored. The impact of high-level plantation and harvesting (during the fruit season) on mangosteen size and levels of bioactive compounds with high antioxidant capacity in mangosteen flesh was found to be greater than that of flat plantations (during the off-season). Mangosteens grown in flatlands during the fruit season exhibited brighter flesh color and faster ripening compared to those grown in hilly areas. Mangosteens from these results contained carbohydrates ranging from 10.3% to 16.9%. Mangosteens cultivated along the Andaman coast exhibited elevated levels of minerals (K 349 mg/100 g, Na 7.76 mg/100 g, and Mn 1.63 mg/100 g) and vitamins, especially B2 (0.10 mg/kg), B6 (0.20 mg/kg), B12 (0.03 mg/kg), and vitamin C (9.25 mg/kg). Conversely, the highest total phenolic content, flavonoids, and antioxidant activity were observed in hilly areas during the fruit season along the Gulf of Thailand (55 mg GAE/100 g, 32 mg QE/100 g, and ABTS values of 88%, respectively). However, mangosteens from hilly areas ripened faster than those from flatlands due to higher total soluble solids and lower fruit firmness. These findings provide valuable insights into the effects of the environment and location, enhancing understanding for year-round mangosteen plantation preparation.

Uncovering the nutraceutical potentials of fermented sago starch “Lemantak” by endophytic fungi

Fermentation food has been widely consumed since ancient times due to its many beneficial properties as well as improved texture and taste. Raw sago starch “lemantak” (RSS “lemantak”) is one of the staple foods in the state of Sarawak. Derived from the bark of Metroxylon sagu, this starch has yet to be investigated in terms of its phytochemical and nutraceutical properties after being subjected to fermentation. This study investigated the nutraceutical of fermented RSS “lemantak” in its phenolic content and antioxidant activity in different fermentation conditions by selected endophytic fungi, Aspergillus niger, Penicillium chermesinum and Fusarium equiseti. This study compared two different fermentation modes and also investigated phenolic production by manipulating the fungal consortia, incubation period as well as the solvent used. It was determined that the best endophyte culture was consortia of Aspergillus niger and Penicillium chermesinum under solid state fermentation (SSF) while monoculture Aspergillus niger was the best fungal culture under SMF. It was found that the dual cultures of Aspergillus niger and Penicillium chermesinum (AP) showed high total phenolic content of 174.95 mg GAE/g and high antioxidant activity at different concentrations ranging from 90.21-76.17% under solid-state fermentation at day 7. In contrast, under submerged fermentation, it was found that consortia of Aspergillus niger and Penicillium chermesinum produced low phenolic content of 11.54 mg GAE/g and had lower antioxidant capacity with the range values of 39.26-34.03%. On the other hand, monoculture Aspergillus niger strives best under SMF at 203.65 mg GAE/g and has good antioxidant activity of 90.72-14.15% of scavenging activity. Nevertheless, it was determined that the dual culture of AP showed high potential based on the phenolic content antioxidant activity under SSF while monoculture A. niger showed potential as a phenolic content producer and antioxidant activity. This study ascertained that the best conditions for fermented RSS “lemantak” with higher phenolic content and antioxidant properties are the methanol extract of fermented RSS inoculated with dual cultures Aspergillus niger and Penicillium chermesinum for a period of 7 days of incubation under SSF.

Investigation of antibiofilm and biological activities of Vaccinium arctostaphylos L.

This study investigated the total phenolic and flavonoid contents and the antioxidant, antimicrobial, antibiofilm and α-glucosidase inhibitory activities of methanol extract from Vaccinium arctostaphylos L. leaf and fruit parts. The highest antioxidant activity with 53 µM TEAC and 0.0084 mg/mL SC50 using the ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays, respectively determined in leaf part. The data indicated that the leaf of the plant had the higher total phenolic content (49 µg/mL GAE) and total flavonoid content (0.071 µg/mL QAE) compared to fruit. The α-glucosidase enzyme activity of the leaves (0.179 mg/mL IC₅₀) was observed to be higher than that of the fruits (0.386 mg/mL IC₅₀). The MIC values of the leaf and fruit parts of blueberry were 6.25 mg/ml and 3.125 mg/ml, respectively. The results of this study indicate that the leaf extract was found to significantly reduce the biofilm-forming capacity of the Acinetobacter baumannii isolate by approximately 3-fold, whereas the fruit extract was observed to have only a marginal effect, reducing the biofilm-forming capacity by approximately 1.4-fold. The effects of plant extracts on microbial biofilms may be examined with a view to combating antibiotic resistance. Also results suggesting that it might be an effective and safety medical plant to prevent or treat diseases associated with oxidative damage and bacterial infections. Consequently, further research on natural substances may lead to the development of treatment options.

Antioxidant and antimicrobial characteristics of mangosteen peel extract and synergistic capacity in beef burger preservation

SummaryThis study aimed to investigate the efficiency of mangosteen peel extract (MPE) in preservation of beef burgers. MPE was first evaluated for its total phenolic content (TPC), total flavonoid content (TFC) and antioxidant and antimicrobial activities. Subsequently, beef burgers were prepared with different MPE amounts (0–1%) and stored for 1 day, 3 days and 5 days. The synthetic antioxidant 2,6‐di‐tert‐butyl‐4‐methyl phenol (BHT) and synthetic antimicrobial sodium benzoate (SB) were used for comparison. The changes of burgers in physicochemical parameters (moisture, cooking loss, storage loss and pH), lipid and protein oxidation (peroxide value, PV; thiobarbituric acid reactive substances, TBARS and carbonyl content), microbiological (total viable count, TVC) and sensory characteristics were assessed. The results revealed that MPE contained a high TPC of 128.93 mg gallic acid equivalent g−1 dry extract and TFC of 62.98 mg rutin equivalent g−1 dry extract. These bioactive compounds rendered MPE with its antioxidant activity approximately equivalent to ascorbic acid and antimicrobial activities against Escherichia coli and Staphylococcus aureus comparable with SB. MPE‐combined burger samples had higher moisture and cooking loss (P < 0.05) but almost equal storage loss and pH value compared with the control samples (P > 0.05). However, the incorporation of MPE into beef burgers did not affect the sensory attributes and preferences of consumers (P > 0.05). The burger with 1% MPE had lower values of PV, TBARS and carbonyl content than all other samples (P < 0.05), including the one added with BHT, indicating the strong potential of MPE as natural antioxidant alternative to prevent the oxidation of lipids and proteins. Through the TVC test, 1% MPE was demonstrated to result in the safe preservation of burgers up to 5 days of storage, equivalent to SB (P > 0.05). Therefore, MPE could become a natural synergistic alternative to both synthetic antioxidant and antimicrobial in the preservation of meat and meat products.