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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.

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.

The purpose of this study was to develop an environment-friendly finishing process for coloring and functionalizing fabrics using the extracts from aronia fruit (AF) and/or aronia leaf (AL).

Coloring and functional compounds were extracted from both AF and AL to prepare dyeing and finishing agents for textiles. The bioactive compounds were identified, and their concentrations were determined by spectrophotometry and high-performance liquid chromatography. The extracts were then used to dye and finish natural fibers. The cotton and wool fabrics treated with AF, AL and a combination of AF + AL extracts were investigated in terms of coloring properties and functionalities, specifically antioxidant capacity and antibacterial property.

According to the obtained results, AF extracts contained significant amounts of anthocyanins and phenols while AL extracts contained higher amounts of phenols with very low levels of anthocyanins. It was successfully demonstrated that the AF and AL extracts can be used to dye fabrics with good color properties. Moreover, textiles treated with aronia extracts inhibited the growth of gram-negative and gram-positive bacteria and exhibited antioxidant properties.

AF extract showed superior coloring and functional properties compared to AL extract. However, the treatment solution containing both AF and AL extracts demonstrated significant synergic effects on the antibacterial and antioxidant properties of the treated fabrics.

The purpose of this study was to examined the health effects of raw and cooked aqueous and methanol extracts of Vigna unguiculata on kidney function in Wistar rats.

Thirty-six Wistar rats (weighing 160 ± 10 g) were randomly assigned into nine (9) groups (n = 4). Group I (control): no extract. Groups II and III (aqueous extract of the cooked 350 mg/kg and 550 mg/kg). Groups IV and V (methanol extracts of cooked 350 mg/kg and 550 mg/kg). Groups VI and VII (methanol extracts of raw 350 mg/kg and 550 mg/kg). Groups VIII and IX (aqueous extract of raw 350 mg/kg and 550 mg/kg). After the seventh day of the trial, the rats were euthanized with chloroform, and blood samples were collected for biochemical analysis.

Results showed that the doses applied for cooked and raw V. unguiculata significantly (p < 0.05) enhanced kidney functions by increasing the body weight, glucose level, concentration of serum urea, creatinine, total protein, potassium and chloride in test groups compared with control. The packed cell volume and haemoglobin concentrations of raw aqueous extract at 550 mg/kg (36.5 ± 5.1; 12.3 ± 2.8) were significantly (p = 0.001) higher (29.8 ± 11.8; 10.3 ± 3.9) than the 350 mg/kg dose of the same extract, and cooked aqueous extract at 350 mg/kg dose was significantly (p = 0.001) higher (28.0 ± 10.1; 9.3 ± 3.4) than that of 550 mg/kg (25.8 ± 4.9; 8.8 ± 3.9) dose of the extracts.

The nutritional content of V. unguiculata potentially can augment the nutritional content of a diet and to a large extent, the regular consumers’ health. Essentially, V. unguiculata is composed of both macro and micronutrients capable of promoting normal kidney function.

The purpose of this paper is to propose an automatic metadata extraction and retrieval system to extract bibliographical information from digital academic documents in portable document formats (PDFs).

The authors use PDFBox to extract text and font size information, a rule-based method to identify titles, and an Hidden Markov Model (HMM) to extract the titles and authors. Finally, the extracted titles and authors (possibly incorrect or incomplete) are sent as query strings to digital libraries (e.g. ACM, IEEE, CiteSeerX, SDOS, and Google Scholar) to retrieve the rest of metadata.

Four experiments are conducted to examine the feasibility of the proposed system. The first experiment compares two different HMM models: multi-state model and one state model (the proposed model). The result shows that one state model can have a comparable performance with multi-state model, but is more suitable to deal with real-world unknown states. The second experiment shows that our proposed model (without the aid of online query) can achieve as good performance as other researcher's model on Cora paper header dataset. In the third experiment the paper examines the performance of our system on a small dataset of 43 real PDF research papers. The result shows that our proposed system (with online query) can perform pretty well on bibliographical data extraction and even outperform the free citation management tool Zotero 3.0. Finally, the paper conducts the fourth experiment with a larger dataset of 103 papers to compare our system with Zotero 4.0. The result shows that our system significantly outperforms Zotero 4.0. The feasibility of the proposed model is thus justified.

For academic implication, the system is unique in two folds: first, the system only uses Cora header set for HMM training, without using other tagged datasets or gazetteers resources, which means the system is light and scalable. Second, the system is workable and can be applied to extracting metadata of real-world PDF files. The extracted bibliographical data can then be imported into citation software such as endnote or refworks to increase researchers’ productivity.

For practical implication, the system can outperform the existing tool, Zotero v4.0. This provides practitioners good chances to develop similar products in real applications; though it might require some knowledge about HMM implementation.

The HMM implementation is not novel. What is innovative is that it actually combines two HMM models. The main model is adapted from Freitag and Mccallum (1999) and the authors add word features of the Nymble HMM (Bikel et al, 1997) to it. The system is workable even without manually tagging the datasets before training the model (the authors just use cora dataset to train and test on real-world PDF papers), as this is significantly different from what other works have done so far. The experimental results have shown sufficient evidence about the feasibility of our proposed method in this aspect.

This paper aims to evaluate the antimicrobial and antioxidant activity of ethanol, methanol and aqueous extracts of the jujube fruit.

The fruit samples were harvested from Ziziphus lotus L. in three regions of Morocco: Aïn Chifae (Immouzer), Saiss (Fez) and Guercif. The fruit extracts were obtained by Soxhlet method using ethanol, methanol and water, and then a phytochemical screening was done for each extract. Total phenolic and total flavonoids contents were also determined. Afterward, the antimicrobial activity of the studied extracts was evaluated using the broth microdilution method. To estimate the total antioxidant effect of these extracts, the DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging and phosphomolybdate tests were performed.

Results showed that the highest content of polyphenols and flavonoids was found for ethanol and methanol extracts, while the lowest content was found in the aqueous extracts for all populations studied. Thus, results showed that the highest content of phenolic compounds was recorded in the population of Fez. Methanol extract of this population was the richest in polyphenols (30.36 mg/g) and in flavonoids (13.03 mg/g). The antimicrobial tests showed that Enterococcus faecalis and Pseudomonas aeruginosa were the most sensitive (6.25 mg/ml), compared to the other tested strains. Based on the minimal bactericidal concentrations/minimal fungicidal concentration or MFC/MIC ratio, it seems that ethanol extracts showed a bactericidal effect against Escherichia coli, Staphylococcus aureus and Bacillus subtillis, and a bacteriostatic effect against Enterococcus faecalis. On the other hand, the methanol extract showed bacteriostatic effect against Enterococcus faecalis and Pseudomonas aeruginosa. In addition, methanol extracts of Ziziphus lotus have significant antioxidant potent.

Methanol and ethanol extracts of Ziziphus lotus fruit have demonstrated strong antimicrobial effect. Moreover, the authors were able to show that the extract of Ziziphus lotus fruit has a very important antioxidant power.