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This study aims to produce a new type of healthy functional kefir by adding olive (Olea europaea) leaf extract and to determine its potential effect on the quality (physicochemical, sensory, phenolic contents and antioxidant properties) of kefir samples during storage at 4°C for 21 days.

For this purpose, four kefir samples were produced by using olive leaf extract in different amounts (A: 0% (control), B: 0.1%, C: 0.15% and D: 0.35%). The physicochemical, sensory, phenolic contents and antioxidant properties of kefir samples were investigated during Days 1, 7, 14 and 21 of storage. The study was conducted to optimize the olive leaf extract addition level to obtain better-quality kefir functional food.

From the results, it was determined that the addition of olive leaf extract affected the entire chemical components of the kefir samples (p < 0.05). It was found that the pH value decreased during storage. By contrast, it was observed that titration acidity values increased. The kefir sample with 0.35% olive leaf extract (D) had the highest total phenolic and antioxidant activity content (1,292.75 mg GAE/L and 10.20 mM TE, respectively) among the samples (p < 0.05). In the sensory analyses, the kefir sample with the highest score – in terms of sensory attributes – was the kefir sample containing 0.15% olive leaf extract (C).

Thus, it was concluded that kefir with added olive leaf extract could serve as a functional kefir of benefit to human health. When we looked at the enrichment studies on kefir as a functional product, no study has been found on the use of olive (Olea europaea) leaf extract, especially with kefir. In this sense, it is thought that the study will contribute to published literature.

This study aims to compare the antioxidant and antimicrobial activity of different parts (tip, mid and base portion) of lemongrass leaves for application as a natural ingredient in the functional drink.

Lemongrass leaf powder was prepared from different parts of leaves and evaluated for nutritional composition. Additionally, the extracts of different portions of lemongrass leaves were analyzed for total phenolics, free radical scavenging activities, ferric reducing antioxidant potential (FRAP) and antimicrobial activities for their application in food products.

Tip portion of lemongrass leaf anticipated significantly (p < 0.05) higher contents of ash, protein, calcium, potassium and iron i.e. 6.2 mg/100 g, 18 mg/100 g, 340 ppm, 819 ppm and 32 ppm, respectively. Maximum (p < 0.05) phenolics (14.7 mg GAE/100 g), 2,2-diphenyl-1-picryl-hydroxyl (86.3%) and FRAP (200 mmol/100 g) were observed in lemongrass leaf tip methanolic extracts. Moreover, lemongrass leaf tip hydro-methanolic extracts portrayed maximum zone of inhibition against E. coli and Staphylococcus aureus i.e. 16.7 and 18.2 mm, respectively.

This study demonstrated higher antimicrobial and antioxidant activities of the tip of lemongrass leaves as compared with mid and base portions, hence suggesting its role in the improvement of physicochemical, antimicrobial and antioxidant properties of food products. Consequently, the application of lemongrass methanolic extract up to 10% remarkably enhanced the nutritional value and sensorial acceptance of the beverages.

The present research draws evidence from laboratory analysis of fresh lemongrass grown in Pakistan. The findings suggest that lemongrass methanolic extracts could be used as a nutritionally rich source of antioxidant activity in functional drinks.

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 paper aims to study the effect of orange peel and moringa leaves extracts on microbiological safety, sensory quality, lipid oxidation and color properties of chicken sausages under frozen storage.

Chicken sausages were prepared by using orange peel, moringa leaves extracts and butylated hydroxytoluene (BHT). The sausages were stored in a freezer at −18°C. Samples were taken at a regular interval of 20 days from the day of production to spoilage of sausages and analyzed for microbiological safety, sensory quality, lipid oxidation and color properties.

In comparison to the control sausage, sausages having BHT, orange peel and moringa leaves extract had a significantly (p < 0.05) lower bacterial, yeast and mold count. All the sausages were microbiologically safe for consumption till the 100th day, and the results of the 120th day crossed the permissible limits. Sensory acceptability scores of sausages were good (>6) throughout the storage period. The color values of sausages were not affected by the addition of orange peel and moringa leaves extract. The extent of lipid oxidation increased during storage, and sausages with BHT, orange peel and moringa leaves extract had significantly (p < 0.05) lower values of thiobarbituric acid reactive substances and free fatty acids (FFAs) toward the end of the storage period.

The observations of this paper endorse the use of orange peel and moringa leaves extract in meat products formulation for acceptable storage stability under frozen conditions.

Moringa oleifera (MO) is a herbal remedy that is rich in essential amino acids and phytochemicals in the leaves, seeds and pods. It is becoming a famous food in various ethnic groups, and the consumption is increasing worldwide. However, there is no safety profile of the hydroalcoholic MO leaf extracts, or documented teratogenicity aspect. This study was sought to compare the antioxidant activity and the teratogenicity of hydroalcoholic MO leaf extracts in the zebrafish embryo.

MO leaves were extracted with aqueous alcohols (ethanol or methanol: water, 80:20 v/v) using the Soxhlet method. The antioxidant capacity was determined using DPPH assay. The concentrations of extracts ranging from 3 to 1,000 µg/mL were used to examine the toxicity and teratogenicity on the zebrafish embryo.

Both hydroalcoholic MO leaf extracts were positive for alkaloids, terpenoids, steroids, tannins, flavonoids, phenols, coumarins, quinones and glycosides, except saponins only absent in aqueous methanol extract. The antioxidant capacity based on lC₅₀, was 15.92 ± 3.62 mg/mL for aqueous methanolic and 25.28 ± 2.89 mg/mL for aqueous ethanolic extract. For acute toxicity, the aqueous methanolic extract has lower LC₅₀ (163.87 ± 12.88 µg/mL) compared to aqueous ethanolic extract (337.48 ± 30.04 µg/mL). The embryo treated with aqueous methanolic extract showed phenotypic defect but not on the aqueous ethanolic extract.

This study suggests that aqueous methanol of MO leaves extract has better antioxidant capacity compared to ethanol, and ethanolic leaf extract is safer (higher LC50 and no teratogenicity) than methanolic extract.

This paper aims to extract the dye colourant from teak leaves using different aqueous mediums (Alkaline, Neutral and Acidic); to characterize the dye in terms of yield %; ash content and moisture content; to standardize the conditions of application of dye extracted from teak leaves on selected natural and synthetic fabrics using selected natural and chemical mordants; to assess the colour value (K/S, L*, c*/ h*, a*, b*) and fastness properties of the dyed samples in terms of wash, rub, light and perspiration fastness; and to develop dyed and printed designs using combinations of mordant and extracted dye.

Stage 1 – Extraction of dye from teak leaves; and characterization of dye: yield% ash content and moisture content. Stage 2 – Preparation of fabrics for dyeing; optimization of mordanting parameters using pre mordanting method followed by post mordanting; and optimization of dyeing parameters. Stage 3 – Testing of dyed fabric – Colour Measurement; K/S L*a*b*/L*c*h*; fastness properties; wash fastness done in the Laundrometer using ISO 2 standard test method; crock fastness done by Crockmeter using AATCC 116–1995 test method; perspiration fastness tested by perspirometer using AATCC 15– 2007 test method; and light fastness assessment in Mercury Bulb Tungsten Filament (MBTF) light fastness tester using AATCC Test Method 16–2004.

The findings of the study show that waste teak leaves can be used as an effective dye for natural as well as synthetic fabrics giving a wide range of colours on wool, silk and nylon. The maximum relative colour strength of the extracted dye on unmordanted dyed samples was found to be at pH 5 on wool and silk and at pH 7 on nylon. A range of shades was obtained with the use of different mordants. The extracted dye showed moderate to good fastness properties in terms of light, wash, rub and perspiration on wool and silk and excellent on nylon. Fastness properties were found to improve with the application of mordants both as pre and post method. Various combinations of mordants and dye result in obtaining pleasing and harmonious colours which were used aesthetically for printing.

Due to time constrains, extraction in an organic medium could not be done, which could be a further scope for study.

Dyeing using teak leaves is a step towards sustainability and effective waste utilization with promising potential for application on natural as well as synthetic fabrics. Good colour with added properties will provide excellent solutions for eco-friendly methods of dyeing.

This paper demonstrates the new possibilities offered by innovative uses of by-products of the timber industry and open good prospects for alternatives to synthetic colourants and new markets for the textile industry. It offers a new tool for the development of slow fashion.

It is a common practice to prune the tree branches to improve wood quality; thus, leaves are easily available as by product from pruning and also from wood harvesting. In the present study, waste teak leaves (Tectona grandis L.) were used for the extraction of dye.

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 aim of this study was to evaluate anti-bacterial anti-fungal activity of six Lamiaceae family coleus plants based on their traditional uses (breast-milk stimulants) from two Asian countries (Malaysia and Indonesia).

Plants leaves of coleus species were collected from Kuantan (Malaysia) and Jakarta (Indonesia). From Kuantan, Coleus aromaticus – Malaysia (CATM), Pogostemon cablin – Malaysia (PCM), Coleus blumei-purple leaves – Malaysia (CBPM), Coleus blumei-red leaves – Malaysia (CBRM), Coleus amboinicus – Malaysia (CALM) and from Jakarta Coleus amboinicus – Indonesia (CALI) were collected freeze dried and extracted with aqueous methanol. The antimicrobial activity of the extract was determined by making use of macro dilution and disc diffusion methods. The selected bacteria and fungus used were namely Bacillus subtilis and Staphylococcus aureus (gram positive) and Escherichia coli and Pseudomonas aeruginosa (gram negative) and Candida albicans (a fungi).

All leaf extracts showed activity at least against one strain of bacteria and the result shows that there were significant differences (p<0.05) between the activities on microorganism. The minimum inhibitory concentration of all leaves extracts ranged from 1.0 to 2.0 mg/ml in inhibiting the growth of S. aureus, E. coli, P. aeruginosa and B. subtilis. This study shows that the coleus plants leaves can be used as anti-bacterial anti-fungal agent apart from the breast-milk stimulation properties.

This research was carried out with a limited grant and it was not possible to study some more aspects, for example, the composition and the active components isolation, etc. Furthermore, to establish the relationship among the components and bacteria or fungus, etc.

This research would have greater impact since the leaves of coleus plants are already in use in some communities for the purpose of breast-milk stimulation and insect bite therapy and many more.

This research takes into consideration the effect of coleus plants on a few bacteria and a fungus which have never been studied before.

Innovative health-promoting approaches of the era have verified phytoceutics as one of the prime therapeutic tools to alleviate numerous health-related ailments. The purpose of this paper is to probe the nutraceutic potential of ginger flowers and leaves against hyperglycemia.

The aqueous extracts of ginger flowers and leaves were observed on Sprague Dawley rats for 8 weeks. Two parallel studies were carried out based on dietary regimes: control and hyperglycemic diets. At the end of the experimental modus, the overnight fed rats were killed to determine the concentration of glucose and insulin in serum. The insulin resistance and insulin secretions were also calculated by formulae by considering fasting glucose and fasting insulin concentrations. Furthermore, the feed and drink intakes, body weight gain and hematological analysis were also carried out.

In streptozotocin-induced hyperglycemic rats, the ginger flowers extract depicted 5.62% reduction; however, ginger leaves extract reduced the glucose concentration up to 7.11% (p = 0.001). Similarly, ginger flowers extract uplifted the insulin concentration up to 3.07%, while, by ginger leaves extract, the insulin value increased to 4.11% (p = 0.002). For the insulin resistance, the ginger flower showed 5.32% decrease; however, the insulin resistance was reduced to 6.48% by ginger leaves (p = 0.014). Moreover, the insulin secretion increased to 18.9% by flower extract and 21.8% by ginger leave extract (p = 0.001). The feed intake and body weight gain increased momentously by the addition of ginger flowers and leaves; however, the drink intake and hematological analysis remained non-significant by the addition of ginger parts.

Conclusively, it was revealed that leaves have more hypoglycemic potential as compared to flowers.

This study aims at extracting and characterizing palm leaf fibers from Elaeis guineensis species of palm trees found in Ethiopia.

The fibers were extracted using three methods: manually, through water retting and chemically with sodium hydroxide. Physical parameters of the extracted fibers were evaluated, including tensile strength, fiber fineness, moisture content, degradation point and functional groups. Its cellulose, hemicellulose and lignin contents were also analyzed.

The results showed that the palm leaf fibers have a comparable fiber strength (170-450 MPa), elongation (0.95-1.25 per cent), fiber length (230-500 mm) and moisture regain (8-10 per cent) to jute, sisal and flax and thus can be used for technical textile application.

The fibers extracted using the water retting method had better properties than the other extraction methods. Its fiber length of 307 mm, cellulose content of 58 per cent, strength of 439 MPa and elongation of 1.24 per cent were the highest for all the extracted fibers. When compared with other fibers, palm leaf fiber properties such as tensile strength (439 MPa), elongation (1.24 per cent), moisture content (7.9-10.4 per cent and degradation point (360-380°C) were consistent with those of jute, sisal and ramie fibers. Hence, palm leaf fibers can be used for technical textile applications such as composite reinforcement.