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The purpose of this paper is to study the inhibitive and adsorption characteristics of ethanol extract of Garcinia kola and Cola nitida for the corrosion of mild steel in H₂SO₄ solutions.

The inhibition efficiencies were evaluated using weight loss and thermometric methods while the adsorption properties were studied using IR spectroscopy.

The inhibition efficiencies of ethanol extracts of Garcinia kola and Cola nitida were comparable and vary with concentration of the extract, period of immersion and with temperature. The extracts act as adsorption inhibitors because of its phytochemical composition. The extracts are adsorbed spontaneously on the surface of mild steel according to Langmuir adsorption isotherms. The mechanism of physical adsorption is proposed from the trend of the inhibition efficiency with temperature and the values of activation energy and some thermodynamic parameters obtained.

The study provides information on the use of ethanol extract of Garcinia kola and Cola nitida as corrosion inhibitors for mild steel. Electrochemical studies such as polarisation and AC impedance spectra will illuminate the mechanistic aspects of the extract.

Ethanol extract of Garcinia kola and Cola nitida are environmentally friendly inhibitors for the corrosion of mild steel in H₂SO₄.

These environmentally friendly inhibitors may find possible applications in metal surface anodising and surface coatings.

To investigate the inhibitive effect of Delonix regia extracts to reduce the corrosion rate of aluminium in acidic media. The study was a trial to find a low cost and environmentally safe inhibitor to reduce the corrosion rate of aluminium.

The inhibition efficiency was evaluated using the hydrogen evolution technique at 30°C. The mechanism of adsorption inhibition and type of adsorption isotherm was characterised from trends of inhibition efficiency and kinetic data.

Delonix regia extracts inhibited the corrosion of aluminium in hydrochloric acid solutions. The inhibition efficiency increased with increasing concentration of the inhibitor but decreased with increase in exposure time. The acid extracts (hydrochloric acid seeds extract (HSE) and hydrochloric acid leaf extract (HLE)) were found to be more effective than the ethanolic extracts (ethanol seeds extract (ASE) and ethanol leaves extract (ALE)) and the inhibition followed the order: HSE (93.6 per cent) > HLE (83.5 per cent) > ASE (63.9 per cent) > ALE (60.4 per cent). The low negative values of ΔG_ad: −20.14 kJ mol⁻¹ for HSE, −18.08 kJ mol⁻¹ for HLE, −15.96 kJ mol⁻¹ for ASE and −15.12 kJ mol⁻¹ for ALE, as calculated from the Langmuir isotherm, indicated that the inhibitor molecules adsorbed onto aluminium by a physiosorption‐based mechanism. A first‐order type of reaction mechanism was obtained from the kinetic treatment of the H₂ gas evolution data.

Further investigations involving electrochemical studies such as polarization method should shed further light on the mechanistic aspects of the corrosion inhibition.

This paper provides new information on the possible application of Delonix regia as an environmentally friendly corrosion inhibitor under the specified conditions. This environmentally friendly inhibitor could find possible applications in metal surface anodizing and surface coatings.

The purpose of this paper is to study the inhibitive and adsorptive characteristics of ethanol extract of Heinsia crinata for the corrosion of mild steel in H₂SO₄ solutions.

The inhibition efficiencies were evaluated using weight loss, thermometric and hydrogen evolution techniques while adsorption properties were studied using IR spectroscopy.

The inhibition efficiency of ethanol extract of Heinsia crinata varies with concentration of the extract, period of immersion and with temperature. The extract acts as an adsorption inhibitor because of its phytochemical composition. The extract is adsorbed spontaneously on the surface of mild steel according to Temkin and Frumkin adsorption isotherms. The mechanism of physical adsorption is proposed from the trend of the inhibition efficiency with temperature and the values of some kinetic and thermodynamic parameters obtained.

The paper provides information on the use of ethanol extract of Heinsia crinata as a corrosion inhibitor. Electrochemical studies such as polarisation and AC impedance spectra will throw more light on the mechanistic aspects of the corrosion inhibition.

Ethanol extract of Heinsia crinata can be used as an environmentally friendly inhibitor for the corrosion of mild steel in H₂SO₄. This environmentally friendly inhibitor could find possible applications in metal surface anodising and surface coatings.

The paper provides information on an environmentally‐friendly corrosion inhibitor.

The purpose of this paper is to evaluate the inhibition activity of Tribulus terrestris L. (T. terrestris) fruits extracts with solvents of increasing polarity against α-glucosidase and α-amylase, and to determine the inhibition mode of the most effective extract against both enzymes.

Hexane, acetone, ethanol and aqueous extracts of T. terrestris fruits were prepared using ultrasonic sequential extraction and analyzed for their α-amylase and α-glucosidase inhibitory activities by specific assay for each enzyme. The modes of inhibitions were detected using Lineweaver–Burk plots.

T. terrestris fruits extracts showed inhibition activity against α-glucosidase and α-amylase which was in the dose-dependent manner. Hexane extract had the highest α-glucosidase inhibition activity (IC₅₀ = 27.28 μg/ml, p = 0.003), followed by acetone and ethanol extracts (IC₅₀ = 60.58 μg/ml and IC₅₀ = 84.21 μg/ml, respectively). The inhibition mode of hexane extract was noncompetitive. While acetone extract showed the highest inhibition activity against α-amylase (IC₅₀ = 6.18 mg/ml, p = 0.002), hexane and ethanol extracts showed no significant difference (IC₅₀ = 13.04 mg/ml and IC₅₀ = 14.20 mg/ml, respectively, p = 0.09). The inhibition mode of acetone extract was competitive.

T. terrestris fruits extracts had strong inhibition activity against α-glucosidase and α-amylase, and they can be used as a promising anti-diabetic agent.

The purpose of this paper is to investigate various extracts of Annona squamosa L (Annonanceae) and Carica papaya L (Caricaceae) seeds for their antioxidant activity, free radical scavenging ability, total phenolic and flavonoid contents.

Samples from both the seeds were prepared by subjecting them to microwave‐assisted extraction. After determining their antioxidant properties and polyphenolic contents, correlation between them was also investigated.

Highest antioxidant activity (3,179.66 g gallic acid equivalent/g of dry extract) and phenol content were registered by chloroform:methanol extract of C. papaya seeds. Maximum radical scavenging activity (3,201.63 ascorbic acid equivalent antioxidant capacity g/100 g of dry extract) was exerted by water extract of A. squamosa seeds, whereas acetone extract of C. papaya registered highest flavonoid content among all extracts. Polar extracts were found to be better free radical scavengers compared with those less polar. Hexane extracts showed least DPPH radical scavenging activity. Acetone proved efficient in extracting flavonoids, whereas phenols were best extracted in a mixture of chloroform and methanol. Phenolic metabolites seem to be contributing significantly towards antioxidant activity of the C. papaya extracts, but less so in the case of A. squamosa.

There have been few reports on antioxidant activity of non‐edible parts of commonly consumed fruits. The research indicates that seeds may be a promising source of antioxidants, which may have therapeutic implications.

This study aims to assess the oxidative stability of avocado oil (AO) at various temperatures, using butylated hydroxytoluene (BHT) as an artificial antioxidant and different concentrations of ultrasonic extract of Chlorella vulgaris.

Extracts of C. vulgaris were obtained using four solvents: water, acetone, ethanol and 80% ethanol-aqueous. Standard techniques were used to conduct qualitative phytochemical screening of the extracts. The extracted samples were analyzed for total phenolics, total flavonoids, antioxidant activity and phenolic compound fractionation. Some physicochemical parameters of AO treated with various concentrations of C. vulgaris ultrasonic extract compared to a 200 ppm BHT and exposed to different temperatures were measured.

The highest phenolic, flavonoids content and antioxidant activity was achieved by 80% ethanolic extract of C. vulgaris . The results showed that exposure of AO to high temperatures led to significant changes in the oil's physicochemical properties. These changes increased as the temperature increased. On the other hand, adding 80% ethanolic extract of C. vulgaris into AO reduced the effect of heat treatment on the change in physicochemical properties.

Adding 80% ethanolic extract of C. vulgaris into AO can potentially reduce the impact of heat treatment on the alteration of physicochemical properties.

The purpose of this study is to extract and characterize a novel natural dye from the leaves of Lannea coromandelica and the extraction with finding ways of dyeing cotton fabric using three mordants.

The colouring agents were extracted from the leaves of Lannea coromandelica using an aqueous extraction method. The extract was characterized using analysis methods of pH, gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis) and cyclic voltammetry measurement. The extract was applied to cotton fabric samples using a non-mordant and three mordants under the two mordanting methods. The dyeing performance of the extracted colouring agent was evaluated using colour fastness properties, colour strength (K/S) and colour space (CIE Lab).

The aqueous dye extract showed reddish-brown colour, and its pH was 5.94. The GC-MS analysis revealed that the dye extract from the leaves of Lannea coromandelica contained active chemical compounds. The UV-vis and FTIR analyses found that groups influenced the reddish-brown colour of the dye extraction. The cyclic voltammetry measurements discovered the electrochemical properties of the dye extraction. The mordanted fabric samples showed better colour fastness properties than the non-mordanted fabric sample. The K/S and CIE Lab results indicate that the cotton fabric samples dyed with mordants showed more significant dye affinities than non-mordanted fabric samples.

Researchers have never discovered that the Lannea coromandelica leaf extract is a natural dye for cotton fabric dyeing. The findings of this study showed that natural dyes extracted from Lannea coromandelica leaf could be an efficient colouring agent for use in cotton fabric.

This study aims to investigate the potential use of potato peel extracts as antibacterial finishes for cotton fabrics against Staphylococcus aureus and Escherichia coli. Potato peels are abundant as waste and provide a natural, cheaper and sustainable alternative means of preventing the spread of bacterial infections on cotton fabric.

This research included the characterization of potato peel extracts, application of the extract onto cotton fabric and efficacy testing of the treated cotton fabric against bacteria. Phytochemical screening, agar well diffusion antibacterial test, minimum inhibitory concentration and Fourier transform infrared (FTIR) tests were used to characterize the extract. Antibacterial efficacy of the treated fabric was determined qualitatively using the disc diffusion assay and quantitatively using the bacteria reduction test.

Phytochemical screening confirmed the presence of several secondary metabolites including phenols and flavonoids. Antibacterial tests revealed a positive response in Escherichia coli and Staphylococcus aureus with a zone of inhibition of 6.50 mm and 5.60 mm, respectively. Additional peaks on the FTIR spectroscopy confirmed the presence of potato peel extract on the treated cotton fabric. The treated cotton fabrics showed efficacy against Staphylococcus aureus and Escherichia coli up to 20 washes.

This study introduced the application of potato peel extracts onto cotton fabrics and assessment of the antibacterial properties before and after washing. Results of this study suggest that potato peel extracts can be used as an organic eco-friendly antibacterial finish for cotton fabrics.

Natural extracts produced with Annona squamosa and Moringa oleifera leaves through the methanol-based solvent were coated on 100% cotton and 80%:20% polyester/cotton blends to improve the functional properties such as antimicrobial activity, wicking, stiffness and crease recovery of the fabric using an eco-friendly 1,2,3,4-butane tetracarboxylic acid (BTCA) crosslinking agent.

In this study, 100% cotton and 80:20% Polyester/Cotton fabrics with surface densities of 113.5 g/m2 and 101 g/m2 were treated BTCA. Eight different samples were produced by padding through the natural extracts. The FTIR investigation was performed on all the fabric samples. These coated fabrics were studied for their antimicrobial activity, wicking, stiffness and crease recovery properties.

It was found that the BTCA cross-linked fabrics showed higher antimicrobial activity against gram-positive and gram-negative bacteria. Similarly, the percentage crease recovery angle was higher for the Annona squamosa coated sample than for Moringa Oleifera leaf extract in both cotton and polyester cotton blend samples. Furthermore, no significant variation in stiffness values was discovered between the control samples of cotton and polyester cotton blend and its treatment one. It was interesting to note that treating the fabrics with cross-linker showed improved vertical wicking properties, which were closer to control fabric values. The study confirms that crosslinking the fabrics with BTCA has improved the functional properties of the fabrics. The zone of inhibition values of BTCA cross-linked moringa methanolic leaves extract coated cotton and polyester cotton blend were 6 to 6.5 cm, which was more than 50% higher than non-BTCA cross-linked fabric, and BTCA cross-linker has improved the vertical wicking properties.

The outcome of this study will help to gain a better understanding of BTCA cross-linkers for improving the functional coating on textile substrates.

This study was conducted to improve the natural extract coating on textile material with eco-friendly aspects, enhancing the commercial utility of these finished fabrics

The purpose of this paper is to systematically review the functionalities, safety regulations and product applications of herb Stevia rebaudiana extract. This plant material is embedded with multiple functionalities such as antioxidant, antidiabetics, anti-inflammation and antimicrobial. The regulations released from global authorities are covered to ensure the safety premise of stevia. Besides, the product applications of the extract of aerial parts of the herb S. rebaudiana helps us to recognize its value from commercial side.

Relevant literatures are selected and obtained from main scientific databases such as Google Scholar, Web of Science, PubMed and trade magazines published between 2000 and 2023. The keywords and their possible combinations such as sweetening, antioxidant, antidiabetics, anti-inflammation, safety and product development were used to ensure the preciseness and completeness of literature searching. Major data such as sweetness, total phenolic content and dose together with latter critical conclusions from searched publications were appropriately used and discussed. In this review, approximately 150 scientific literatures were meticulously ordered and analyzed. In applications, it is the first time that sentiment analysis was used to obtain a market assessment of the stevia-containing products.

This review paper helps rearrange the scientific affairs of those stevia extract’s functions like sweetening, antioxidant, antidiabetics and inflammation. Sweetness indexes of steviol glycosides were summarized together for comparison while various in vitro and in vivo approaches were reviewed to quantify those functions’ capacities and to depict the related mechanism. The regulation of steviol glycoside compounds such as rebaudioside A was established by global authorities such as US Food and Drug Administration and Joint FAO/World Health Organization Expert Committee to ensure the safety endorsement before commercialization. Then, this study discussed about the market performance of stevia ingredients or products with the self-developed data analytics. This study also investigated the product development progress of stevia-containing food products in the categories of beverage, bakery, dairy and confectionery. Those stevia-containing food consumer goods can be acceptable by certain consumers.

This review paper precisely presents the evidential information about the stevia’s multiple functionalities with mechanisms and global regulation milestones. To the best of the authors’ knowledge, it is then the first time to probe the stevia-containing products’ market performance through data analytics.