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This study investigated the growing environmental concern of particulate matter (PM)-induced pulmonary injury and explored novel preventive strategies. In particular, it evaluated the protective effects of Atractylodes japonica Koidz. ex. Kitam root extract (AJ), which is known for its anti-inflammatory and antioxidant properties, against PM2.5-induced subacute pulmonary injuries in Balb/c mice. The experimental design involved administering AJ at a concentration from 400 to 100 mg/kg over a ten-day period, with comparisons made to the mucolytic agent ambroxol hydrochloride (AX). The results revealed that AJ significantly alleviated PM2.5-induced pulmonary injuries, mucus overproduction, and respiratory acidosis in a dose-dependent manner. Notably, body surface redness was reduced by up to 55% at a concentration of 100 mg/kg compared to the control. These effects were evidenced by reduced mRNA expression of the mucus-associated genes MUC5B and MUC5AC and increased concentrations of substance P (up to 475%) and acetylcholine (up to 355%) in the lungs at 400 mg/kg, compared to the intact vehicle control. Particularly, the 400 mg/kg dose of AJ demonstrated comparable effectiveness to AX, highlighting its potent mucolytic and expectorant activities. The results of this study highlight the fact that AJ could act as a promising alternative for respiratory protection, with potential applications as a functional food ingredient. This study substantiates AJ's role in enhancing respiratory health, emphasizing its capacity as a candidate for further development into therapeutic agents against toxic environmental exposure. [ABSTRACT FROM AUTHOR]

This study focuses on developing a fried fish cake prototype with improved quality and extended shelf-life, enabling room-temperature distribution through an innovative high-temperature and high-process retort method. Surimi-based products typically necessitate cold storage and a refrigerated distribution system, affecting their physical properties and flavor while escalating costs. By incorporating Transglutaminase (TGase), trehalose, and herbal oils, and optimizing the heating process using the response surface methodology, this research addresses challenges related to changes in physical properties, color, and off-flavors during high-temperature and high-pressure treatment. The addition of 0.37% ACTIVA-K TGase significantly enhanced gel strength by promoting protein cross-linking, while 0.75% trehalose improved color stability by suppressing browning, thus enhancing visual appeal. A 0.1% concentration of bay oil effectively enhanced the flavor profile by masking undesirable odors without compromising the sensory quality. Optimized processing conditions maximized DPPH radical scavenging activity, whiteness, and gel strength, ensuring superior product quality and safety. Nutritional analysis confirmed a balanced composition of moisture, protein, essential amino acids, and minerals, in accordance with Korean national standards for acid values. Microstructural examination revealed a uniform network structure, contributing to excellent texture and sensory evaluations. Shelf-life predictions indicated a storage duration of approximately 19 months, surpassing commercially available products and offering a competitive edge. This novel approach allows surimi-based products to be stored and distributed at room temperature, while also providing the potential for increased profitability. [ABSTRACT FROM AUTHOR]

Fish muscle and byproducts represent a valuable source of bioactive compounds, with their protein hydrolysates exhibiting noteworthy antioxidant properties. This study assessed the antioxidant activity of protein hydrolysates derived from the muscle and byproducts of redlip mullet (Chelon haematocheilus), utilizing different proteases (Neutrase, Alcalase, and Protamex). Hydrolysates were prepared from various parts of the fish, including muscle (white and red meat) and byproducts (frames, head, viscera, fins, skin, and scales). The enzymatic hydrolysis resulted in the highest degree of hydrolysis, achieving 83.24 ± 1.45% for skin at 60 min and 82.14 ± 4.35% for head at 30 min, when treated with Neutrase. Frames treated with Neutrase exhibited the highest protein concentration, measured at 1873.01 ± 71.11 µg/mL at 15 min. Significantly, skin hydrolysates treated with Protamex showed the highest DPPH• scavenging activity (70.07 ± 3.99% at 120 min), while those treated with Alcalase demonstrated the highest ABTS• scavenging activity (93.47 ± 0.02% at 15 min). The highest superoxide dismutase (SOD) activity (92.01 ± 1.47%) was observed in head hydrolysates treated with Protamex after 90 min. These results suggest that C. haematocheilus protein hydrolysates possess significant antioxidant activity within a short time frame of less than 120 min. [ABSTRACT FROM AUTHOR]

Climacteric symptoms, as well as postmenopausal estrogen deficiency, have been associated with many psychological problems and the risk of osteoporosis and heart disease. Therefore, in this study, we aimed to evaluate, for the first time, the dose-dependent effect of water chestnut (WC), also known as Trapa bicornis, a fruit extract, on ovariectomy (OVX)-induced menopause in ICR mice. After bilateral OVX surgery, 200, 100, and 50 mg/kg of WC and 200 mg/kg of pomegranate concentrate powder (PCP) were administered orally for 84 days from 4 weeks after OVX operation. Then, anti-climacteric activities were evaluated in five groups: (1) estrogenic, (2) anti-obesity, (3) hypolipidemic, (4) hepatoprotective, and (5) anti-osteoporosis effects. Different biochemical assays, histopathological and morphological inspections, and mRNA expression findings showed that OVX-induced estrogen deficiency-related AMPK decrease was associated with climacteric symptoms such as obesity, hyperlipidemia, hepatic steatosis, and osteoporosis in ICR mice. However, these climacteric effects were reversed in OVX rats by treating them with WC at a dose relative to the same dose of PCP in OVX-ICR mice (200 and 100 mg/kg). Water chestnut fruit extract demonstrated promise as a complementary treatment for menopausal symptoms, indicating possible uses in the health of women through supplements or prescription drugs. [ABSTRACT FROM AUTHOR]

Simple Summary: This study addresses the challenges of waste generated in ready-to-eat (RTE) food production, with a focus on mackerel processing. By-products such as head and intestine are often discarded as waste, prompting the investigation of an eco-friendly solution using black soldier fly larvae (BSF larvae) as bio-converters. In this study, BSF larvae efficiently transformed mackerel heads (MH) into valuable biomass, with the most substantial growth occurring when BSF larvae were fed a diet containing 20% MH waste. Beyond this concentration, the growth rate declined, indicating an optimal waste conversion point. These findings hold societal value on multiple fronts. Firstly, this study introduces an innovative and eco-friendly approach for seafood industry waste management by converting MH waste into valuable biomass and reducing the environmental impact of waste disposal. Furthermore, the research underscores the potential of BSF larvae as a sustainable alternative animal feed source, potentially decreasing reliance on conventional feeds. In conclusion, this study offers a practical solution for waste management and sustainable food production, aligning with broader efforts to establish an eco-friendly and efficient food industry. The seafood processing industry generates significant waste, including mackerel heads (MH), constituting 20–32% of total waste. This study explored the potential of utilizing MH as a feed source for black soldier fly larvae (BSF larvae). BSF larvae are known for their ability to efficiently convert organic materials into nutrient-rich biomass. Five concentrations of MH (0, 10, 20, 30, 40, and 50% in chicken feed) were fed to BSF larvae for eight days. After harvesting, their growth, MH conversion efficiency, nutritional content, and heavy metals reduction potential were measured. BSF larvae showed optimal growth when fed with a feed containing 20% MH, resulting in a 14.36-fold increase in weight compared to the control group, as determined by the Fisher's Least Significant Difference Test. BSF larvae maintained a survival rate of 99.33%. With the lowest feed conversion ratio (FCR) of 2.09 at 20% MH, feed efficiency was improved by up to 65.15%, and feed reduction up to 73.53%. MH enhanced lipid and protein content in BSF larvae. Furthermore, BSF larvae in this study showed higher polyunsaturated fatty acids (PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as other amino acids which are required for breeding animals. The current study highlights the potential of MH as a feed source for BSF larvae, improving nutritional biomass. It also suggests BSF larvae as an eco-friendly option for handling seafood processing waste and as an alternative feed source for animals. [ABSTRACT FROM AUTHOR]

The edible brown seaweed, Ecklonia cava, is highly valued for its bioactive compounds, and is widely used in food supplements and functional foods. The increasing demand for this seaweed in the food industry emphasizes the necessity for sustainable cultivation practices. This study focused on inducing callus in the meristem and stipe of E. cava using different culture media: Provasoli's enriched seawater medium (PESI), enriched artificial seawater medium (ESAW), artificial enriched seawater medium (ASP2), or Von Stosch's enriched seawater medium (VS). Various abiotic stress factors (photoperiod, agar concentration, and temperature), growth regulators, carbon sources, polyamines, and plasma treatments were explored for their impact on callus induction. Both stipe and meristem explants developed callus within three to six weeks across all media except ASP2. Callus development was favored at temperatures between 8 to 13 °C and in the absence of light. Stipe explants showed a higher callus induction rate (up to 65.59 ± 6.24%) compared to meristem (up to 57.53 ± 8.32%). Meristem explants showed optimal callus induction in PESI medium with a low concentration of indole-3-acetic acid (IAA; 40.93 ± 8.65%). However, higher concentrations of IAA and 1-naphthaleneacetic acid (NAA) reduced meristem callus induction. Stipe showed high induced-callus (up to 50.37 ± 5.17%) in PESI medium with low concentrations of IAA, NAA, and 6-benzylaminopurine (BAP). Both stipe and meristem explants induced largest callus at 2% sucrose, but higher carbon source concentrations reduced callus induction. Spermine (Spm) at 1 µM resulted in high induced calluses; however, increasing Spm concentrations decreased callus induction. This tissue culture technique not only supports mass cultivation of E. cava, but also holds potential for extending to other seaweed species, contributing to the sustainability of seaweed stocks for the food industry. [ABSTRACT FROM AUTHOR]

The deep-sea whelk Buccinum tenuissimum Kuroda is highly sought-after as food in East Asian countries, notably, Korea and Japan. However, it lacks official recognition as a food product in Korea. This study aimed to assess its nutritional composition and safety for the potential development of seafood products. The nutritional analysis revealed high protein (13.54–20.47 g/100 g whelk), fat (0.85–8.59 g/100 g whelk), carbohydrate (1.55–12.81 g/100 g whelk), and dietary fiber (1.25–1.95 g/100 g whelk) contents in both muscle and gut samples, with energy contents ranging from 339.11 ± 1.64 to 692.00 ± 3.21 kJ/100 g. Key minerals, including iron, potassium, calcium, and sodium, and essential fatty acids, including eicosapentaenoic acid, docosahexaenoic acid, arachidonic acid, omega-3, and omega-6 fatty acids, were abundant, making it a potential supplementary food. Notably, heavy metal levels met the Korean standards for seafood safety. No trans fats, radioactivity concerning the radioactive isotopes 134Cs/137Cs and 131I, or pathogenic bacteria were detected. This confirms the safety and nutritional value of deep-sea whelks, suggesting their potential for developing seafood products rich in beneficial components, which could enhance nutrition and food security while contributing to economic growth. [ABSTRACT FROM AUTHOR]

Surimi-based products typically demand cold storage and a cold chain distribution system, which not only affects their physical properties and flavor but also escalates production costs. In this study, we introduced a novel high-temperature and high-pressure retort processing method to enable room temperature storage and distribution of a surimi-based product, a fish paste cake. Our optimization efforts focused on refining the processing conditions for the fish paste cake. This included incorporating transglutaminase, sugar additives, natural herbal or seaweed extracts, and optimizing retort processing conditions to enhance textural properties, minimize browning and off flavor, and extend the shelf-life of the product. Our results demonstrated that the addition of 0.3% ACTIVA TG-K, 1.0% trehalose, and 0.5% sea tangle extract during the production process significantly enhanced the gel strength, minimized browning, and improved the overall flavor of the fish paste cake prototype. Importantly, the developed prototype exhibited favorable biochemical, textual, nutritional, and sensory properties, extending the shelf-life up to 160 days without compromising physical, chemical, or sensory attributes. In addition, the developed prototype exhibited improved elasticity, compared to control groups. The innovative process not only facilitates room temperature storage and distribution of surimi-based products but also holds potential for generating additional profits. [ABSTRACT FROM AUTHOR]

The effects of coffee (Coffea arabica L.) berry pulp extracts (CBP extracts) on the improvement of diabetes, obesity, and non-alcoholic fatty liver disease (NAFLD) were evaluated using various in vitro antioxidant activity assays and through a high-fat diet-induced mild diabetic obese mouse model. After an 84-day oral administration of CBP extracts (400–100 mg/kg), bioactivities were evaluated. The in vitro analysis showed the highest DPPH● scavenging activity of 73.10 ± 4.27%, ABTS● scavenging activity of 41.18 ± 1.14%, and SOD activity of 56.24 ± 2.81%, at a CBP extract concentration of 1000 µg/mL. The in vivo analysis of the CBP extracts showed favorable and dose-dependent anti-obesity, anti-diabetic, NAFLD, nephropathy, and hyperlipidemia refinement effects through hepatic glucose enzyme activity, 5′-AMP-activated protein kinase (AMPK) up-regulation, antioxidant activity, lipid metabolism-related gene expression, and pancreatic lipid digestion enzyme modulatory activities. This study shows that an appropriate oral dosage of CBP extracts could function as a potent herbal formulation for a refinement agent or medicinal food ingredient to control type 2 diabetes and related complications. [ABSTRACT FROM AUTHOR]

Obesity is implicated as a factor in several serious metabolic conditions, including hypertension, cardiovascular disease, and type II diabetes. This study aimed at the development of more potent and safer alternative medications to address these metabolic diseases with minimal side effects. Following oral administration of 400, 200, and 100 of mg/kg fermented Schizandrae fructus pomace extracts (fSFP) once daily for 84 days to high-fat diet (HFD)-supplied ICR mice, respectively, we measured liver enzyme activity related to glucose metabolism, gene expression related to fat metabolism, anti-obesity effect, liver and kidney protection effect, and anti-diabetic effect to confirm the effect of fSFP on improving related complications including obesity and diabetes. In the HFD control group, significant obesity and type II diabetes symptoms were developed. However, oral administration of 200 mg/kg of fSFP showed a protective effect on kidney damage and diabetes complications related to insulin-resistant type II diabetes mellitus, as well as oxidative stress-induced abnormalities in glucose and fat metabolism, comparable to that of metformin 250 mg/kg, a positive control. The major bioactive substance in fSFP was identified as shizandrin, which was quantitated as 1.25 mg/g (w/w). Therefore, fSFP extracts can be taken as a medicinal food in combating obesity and diabetes, two current major health concerns. [ABSTRACT FROM AUTHOR]

We prepared a long-arm octopus Jangjorim prototype (LOJP) by optimizing the ratio of ingredients for seasoning and establishing heat sterilization parameters. The optimal amounts of purified water (2.9–56.6%, A), starch syrup (0.3–37.8%, B), and soy sauce (25.5–71.5%, C) for the production of seasoning soy sauce were obtained using response surface analysis. The LOJP was prepared by combining A, B, and C under the optimal conditions and evaluated for consumer preferences and physicochemical, nutritional, and microbiological properties and compared with Korea's legal management standards for geriatric nutrition. The hardness of the LOJP produced using the optimal mixing ratio of purified water (51.2%, 154.0 g), starch syrup (29.3%, 308.0 g), and soy sauce (19.5%, 256.9 g) was 36.7 × 1000 N/m2. This value was lower than the hardness of raw octopus (2153.6 × 1000 N/m2) by 2116.9 × 1000 N/m2. It received the highest score (8.7) in the preference evaluation of older consumers. The LOJP was classified as level 2, allowing consumption through the gums of elderly consumers per Korea's food standards for the elderly. The LOJP was the product highly preferred by elderly consumers with chewing disorders due to its ease of intake and nutritional content. [ABSTRACT FROM AUTHOR]

Background and Objectives: This study evaluated the in vitro anti-adipogenic and anti-inflammatory properties of black cumin (Nigella sativa L.) seed extract (BCS extract) as a potential candidate for developing herbal formulations targeting metabolic disorders. Materials and Methods: We evaluated the BCS extract by assessing its 2,2-diphenyl-1-picrohydrazyl (DPPH) radical scavenging activity, levels of prostaglandin E2 (PGE2) and nitric oxide (NO), and mRNA expression levels of key pro-inflammatory mediators. We also quantified the phosphorylation of nuclear factor kappa light chain enhancer of activated B cells (NF-κB) and mitogen-activated protein kinases (MAPK) signaling molecules. To assess anti-adipogenic effects, we used differentiated 3T3-L1 cells and BCS extract in doses from 10 to 100 μg/mL. We also determined mRNA levels of key adipogenic genes, including peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhancer binding protein α (C/BEPα), adipocyte protein 2 (aP2), lipoprotein lipase (LPL), fatty acid synthase (FAS), and sterol-regulated element-binding protein 1c (SREBP-1c) using real-time quantitative polymerase chain reaction (qPCR). Results: This study showed a concentration-dependent DPPH radical scavenging activity and no toxicity at concentrations up to 30 μg/mL in Raw264.7 cells. BCS extract showed an IC50 of 328.77 ± 20.52 μg/mL. Notably, pre-treatment with BCS extract (30 μg/mL) significantly enhanced cell viability in lipopolysaccharide (LPS)-treated Raw264.7 cells. BCS extract treatment effectively inhibited LPS-induced production of PGE2 and NO, as well as the expression of monocyte chemoattractant protein-1 (MCP-1), tumor necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), inducible NO synthase (iNOS), interleukin (IL)-1β and IL-6, possibly by limiting the phosphorylation of p38, p65, inhibitory κBα (I-κBα), and c-Jun N-terminal kinase (JNK). It also significantly attenuated lipid accumulation and key adipogenic genes in 3T3-L1 cells. Conclusions: This study highlights the in vitro anti-adipogenic and anti-inflammatory potential of BCS extract, underscoring its potential as a promising candidate for managing metabolic disorders. [ABSTRACT FROM AUTHOR]

Featured Application: A sausage for elderly consumers with chewing disorders, which complies with nutritional and safety standards, was developed. Modern consumers, especially the elderly, have a keen interest in healthy food choices. This study was conducted with the objective of developing squid paste sausages that are easily consumable by elderly individuals while also fulfilling their nutritional requirements. Response surface methodology (RSM) was employed to determine the ideal proportions for mixing raw common squid (RCS; 2.9–56.6%, A), isolated soy protein paste (ISPP; 0.3–37.8%, B), and surimi paste (SP; 25.5–64.7%, C) in order to create a common squid paste sausage prototype (CSPSP). The CSPSP underwent a comprehensive evaluation, encompassing its physicochemical, nutritional, and microbiological attributes, as well as consumer preferences, and was compared to Republic of Korea's standards for senior-friendly foods. The optimal mixing ratios derived through RSM were as follows: RCSF, 38.7%; ISPP, 21.2%; and SP, 40.1%. Consequently, the hardness of CSPSP (CSPSP-A) prepared with these ratios was measured at 27.8 × 1000 N/m2, a remarkable 95.0% reduction compared to CSPSP-N. Moreover, the texture preference for CSPSP-A was rated at 8.5, signifying the highest level of preference. As a result, CSPSP-A earned a second-grade rating, indicating its suitability for safe consumption by elderly individuals with chewing disorders. [ABSTRACT FROM AUTHOR]

Considering the need for developing new senior-friendly processed seafood, this study aimed to develop octopus pulpo with high preference and excellent quality characteristics for elderly individuals by optimizing the vinegar immersion and sous vide softening treatment conditions for octopus (Octopus vulgaris) arms. The optimal sous vide heating temperature (70.0–100.0 °C), time (69.5–170.5 min), and vinegar concentration (0.2–0.8%) were established using response surface methodology (RSM). The pulpo prototype was produced using an octopus arm softened under optimal conditions and seasoned with a potato and olive oil sauce. The physicochemical and nutritional properties of the prototype were evaluated, followed by sensory evaluation and safety assessments. The hardness of softened octopuses obtained by 0.48% vinegar immersion and sous vide treatment (84.3 °C, 139.8 min), determined using RSM, was 394.5 × 1000 N/m2, showing a reduction of 83.0%; this was confirmed by electron microscopic observation. The texture of the pulpo prototype with softened octopus arms showed the highest preference (8.4 points) and high physicochemical and nutritional properties. Overall, the octopus pulpo a La Gallega prototype produced using texture-modified octopus arms was suitable for consumption by elderly people with chewing disorders and could help improve their quality of life. [ABSTRACT FROM AUTHOR]

The use of natural products in developing respiratory-function-protective pharmaceuticals is actively progressing. However, in this context, the improvement effects of young Asian pear (Pyrus pyrifolia Nakai) extracts have not been evaluated yet. Thus, this study investigated the anti-inflammatory and lung damage improvement effects of immature Asian pear extract (IAP; 400, 200, and 100 mg/kg) using a particulate matter 2.5 μm (PM2.5)-induced sub-acute lung injury mouse model. The experimental results were compared with dexamethasone (0.75 mg/kg), used as a control drug. After two intranasal instillations of PM2.5 and ten doses of IAP extract for eight days, changes in macroscopic lung autopsy, leukocyte fractionation from bronchoalveolar lavage fluid, lung antioxidant defense system, lung histopathology, and mRNA expression in lung tissue were confirmed. Stress-induced inflammatory lung damage through the increased expression of PM2.5-induced PI3K/Akt and p38 MAPK mRNA was significantly suppressed via the administration of IAP extract (400–100 mg/kg). Furthermore, IAP extract administration promoted serous fluid production in lung tissue, increased substance P and ACh levels, and decreased mucus-production-related expression of MUC5AC and MUC5B mRNA. Interestingly, the observed effects showed a dose-dependent manner without serious hepatotoxicity. The results of this study indicate that a proper oral administration of IAP extract could be helpful in protecting against lung diseases, positioning IAP extract as a potential candidate for an alternative agent to safeguard the respiratory system. [ABSTRACT FROM AUTHOR]

Allergic asthma is a chronic inflammatory disease characterized by the infiltration of leukocytes, particularly eosinophils, into the airways, resulting in respiratory dysfunction. To develop new asthma treatment materials with minimal side effects and excellent bioactivities, we evaluated the efficacy of immature Asian pear extract (IAP extract; 400–100 mg/kg) in alleviating ovalbumin (OVA)-induced asthma in female C57BL/6J mice. This study assesses various parameters associated with OVA-induced allergic asthma including lung weight, macroscopic necropsy findings, the total cell count in bronchoalveolar lavage fluid (BALF), the total leukocyte count and leukocyte differential count, serum ovalbumin-specific Ig E (OVA-sIg E) levels, interleukin (IL)-4 and IL-5 contents in BALF, histopathological changes in the lungs, and alterations in oxidative stress and inflammation-related mRNA expressions. The results of this study demonstrate clear asthma-related findings in the OVA control group. However, the oral administration of IAP extract (at doses ranging from 400 to 100 mg/kg) significantly suppressed the anti-inflammatory and antioxidant activities by regulating the expressions of phosphoinositide 3-kinase/protein kinase B/phosphatase and TENsin homolog deleted on chromosome 10 (PI3K/Akt/PTEN), p38 mitogen-activated protein kinase (p38 MAPK), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in a dose-dependent manner. These effects are comparable to those observed with dexamethasone at a concentration of 0.75 mg/kg. As a result, the oral administration of an appropriate dose of IAP extract holds promise as a potential natural drug or health-functional food material for improving respiratory function. [ABSTRACT FROM AUTHOR]

This study investigated the expectorant effects of immature Asian pear extract (IAP; Pyrus pyrifolia Nakai) on subacute pulmonary injuries in Balb/c mice induced by particulate matter with a diameter of approximately 2.5 μm (PM2.5). IAP was administered at three doses, namely, 400, 200, and 100 mg/kg. The body weight and weight gain changes, lung weights, lung and body surface gross inspections, tracheal secretions, and substance P and ACh content in lung tissue homogenate were observed one day after the tenth IAP administration. The mRNA expression of the genes related to mucus production and lung histopathology was compared with that of the negative and positive controls. Favorable pulmonary protective effects on PM2.5-induced subacute pulmonary injuries, mucus overproduction, and respiratory acidosis were observed in groups treated with IAP at all three doses, possibly through potent anti-inflammatory and mucolytic expectorant activities mediated by the increase in the content of lung substances P and ACh and the downregulation of lung MUC5AC and MUC5B mRNA expression in a dose-dependent manner. The results of this study show that an appropriate oral administration of IAP has sufficient pulmonary protective effects and can be used as a candidate for the development of functional food ingredients. [ABSTRACT FROM AUTHOR]

The present study was aimed at investigating the optimization of extraction variables for food grade quality agar from Gracilaria tenuistipitata, so far, the first study on Bangladeshi seaweed. Water (native)‐ and NaOH (alkali)‐pretreated agars were comparatively analyzed by several physicochemical parameters. All extraction variables significantly affected the agar yield in both extraction conditions. Alkali‐pretreated agar provided a better yield (12–13% w/w) and gel strength (201 g/cm2) in extraction conditions as followed by 2% NaOH pretreatment at 30°C for 3 h, seaweed to water ratio at 1:150, and extraction temperature at 100°C for 2 h. Gelling and melting temperatures, color, and pH values of both agars were found to be comparable with commercial agar. Significantly higher sulfate contents including organic and inorganic and total carotenoids were reported in native (3.14% and 1.29 μg/mL) than that in alkali‐pretreated agar (1.27% and 0.62 μg/mL). FTIR spectrum demonstrated the purity of the agar as characterized by the stronger relative intensity with higher degree of conversion of L‐galactose 6‐sulfate to 3,6‐anhydrogalactose in alkali pretreatment group than that of native ones. Moreover, antioxidant activity (% DPPH scavenging) was observed and confirmed by IC50 values of 5.42 and 9.02 mg/mL in water‐ and alkali‐pretreated agars, respectively. The results suggested that agar from G. tenuistipitata with optimized alkali extraction conditions could promote cost‐effective yield with improved physicochemical characteristics and biofunctional values upon consumption by the consumers as food materials. [ABSTRACT FROM AUTHOR]