Husk Extract Research Articles

PENGARUH SUHU DAN WAKTU MASERASI TERHADAP AKTIVITAS ANTIOKSIDAN EKSTRAK KULIT BUAH KAKAO (Theobroma cacao L.)

Cocoa pod husk is a by-product of cocoa processing which is quite abundant and has not been used optimally. Cacao pod husk can be used more optimally by extracting, its content of polyphenol compounds which can be used as natural antioxidants. The aim of this study were to determine the effect of temperature and maceration time of cocoa pod husk extract as a source of antioxidants and to determine the best type of temperature and maceration time to produce cocoa pod husk extract as a source of antioxidants. This experiment was designed by using factorial randomized block design. The first factor was type of maceration temperature consisting of 30±2°C, 45±2°C and 60±2°C. The second factor was maceration time, which were done for 24, 36 and 48 h. The data were analyzed with analysis of variance and continued with the Tukey test. The results showed that the temperature and time of maceration had a very significant effect on yield, total phenolic and antioxidant capacity of cocoa pod husk extract. Interactions between treatments had a very significant effect on total phenolic and antioxidant capacity but did not significantly affect the yield of cocoa pod husk extract. The best treatment for producing cocoa pod husk extract as a source of antioxidants was using maceration temperature 60±2°C and maceration time for 36 h with yield characteristics 5,28±0,15%, total phenolic at 168.16±0,06 mg GAE/g and capacity antioxidant 130.94±0.84 mg GAEAC/g.
 Keywords: Cocoa pod husk, extraction, temperature, time, antioxidants.

Simultaneous quantification of five bioactive 16-deoxybarringtogenol C triterpenoid saponins in rat plasma by HPLC-MS: Application to a pharmacokinetic study after oral administration of Xanthoceras sorbifolia Bunge husks extract

AbstractIn this study, a simple and rapid liquid chromatography-mass spectrometry method was developed to simultaneously determinate five 16-deoxybarringtogenol C triterpenoid saponins with the potential of neuroprotection in rat plasma following the oral administration of the Xanthoceras sorbifolia Bunge husks extract. With digoxin as the internal standard, the plasma samples were pre-treated by ethyl acetate-isopropanol (1:1, v/v). The chromatographic separation of the five analytes was performed using a Phenomenex C18 column (250 mm × 4.6 mm, 5.0 mm) with a mobile phase of 0.05% formic acid (A)-acetonitrile (B). The mass spectrometric detection was carried out in the selected ion mode in positive ionization. The extraction recoveries of the five analytes were all over 71.28%. The established method was fully validated in line with the ICH and Food and Drug Administration (FDA) guidelines and successfully applied to the pharmacokinetic study on the five analytes in rat plasma. The terminal half-life (t1/2) of the five analytes was 2.92 ± 0.57, 5.52 ± 1.75, 2.48 ± 0.62, 2.95 ± 0.94, and 2.34 ± 0.81, respectively. This study was purposed to investigate the oral pharmacokinetic parameters and gain an in-depth insight into the reasonable preclinical use of the husks extract derived from X. sorbifolia Bunge.

Theoretical and surface/electrochemical investigations of walnut fruit green husk extract as effective inhibitor for mild-steel corrosion in 1M HCl electrolyte

The present paper has studied the corrosion inhibition property of Juglone extracted from walnut (Juglans regia L.) green husk for mild steel samples exposed to an acid electrolyte (1 M HCl). Besides, via computer modelings, the attraction forces of the inhibitors/metal surface were explored. The corrosion inhibition efficiency of the organic inhibitor was evaluated using potentiodynamic polarization as well as EIS techniques. In addition, XPS, FT-IR, SEM, AFM, and UV–visible spectroscopy have been used to study the inhibition mechanism of the agricultural waste extract in the corrosive media. Quantum chemical calculations based on DFT theory and molecular dynamic simulations were investigated on the adsorbed Juglone inhibitors. The obtained results indicated that the efficiency of the used inhibitor was enhanced with increasing the concentration of green corrosion inhibitor (GCI) and reached 95% in the presence of 800 ppm after 8 h immersion. Moreover, the average roughness of the exposed metal to the corrosive electrolyte decreased from 68.2 ± 8.3 nm for the blank solution to 3.4 ± 0.3 nm for the solution containing 800 ppm GCI. Furthermore, the Tafel extrapolated polarization results revealed that the extracted GCI functioned as a mixed-type corrosion inhibitor. Finally, the obtained analysis results are supported by theoretical data.

Exploring natural colorant behavior of husk of durum (Triticum durum Desf.) and bread (Triticum aestivum L.) wheat species for sustainable cotton fabric dyeing.

Revival of natural colorants in textile dyeing is one of the important strategies to reduce synthetic chemical-based environmental pollution. The study has been conducted to explore the coloring potential of durum (Triticum durum Desf.) and bread (Triticum astivum L.) wheat husk for fabric dyeing. The results showed that both wheat species husk could be an excellent source of natural dye, if extracted in alkaline medium. It has been observed that durum wheat husk based dye worked best at 70°C with a pH 11.0 and salt concentration of 8.0 g/100 ml of solution. Similarly, alkaline extract of bread wheat husk worked better at 80°C with dyeing solution pH 9.0 and salt concentration of 8.0 g/100 ml. Bio-mordanting experiments results revealed pomegranate rind (7%) as most effective bio-mordant to obtain high color strength of wheat husk treated fabric. In chemical-mordanting, tannic acid (5%) as pre-mordant and chrome (5%) as post-mordant have improved the color strength more than all other quantities of employed mordants. FTIR analysis indicated the presence of flavonoids as major colorant compounds in wheat husk-based natural dye. Suggested ISO standards for colorfastness illustrated good color strength ratings of husk-based dyed fabric when treated with bio-mordants as compared to chemical counterparts. Hence, husk of both bread and durum wheat species has great potential to be used as source of eco-friendly natural colorant for cotton dyeing.

Dependence of the Ripeness Stage on the Antioxidant and Antimicrobial Properties of Walnut (Juglans regia L.) Green Husk Extracts from Industrial By-Products.

Walnut green husk (WGH) is a waste generated by the walnut (Juglans regia L.) harvest industry. It represents a natural source of polyphenols, compounds with antioxidant and antimicrobial activities, but their activity could be dependent on the ripeness stage of the raw material. In this study, the effect of the different ripeness stages—open (OH) and closed (CH) husks—on the antioxidant and antimicrobial properties of WGH extracts were analyzed, emphasizing the influence of the extracts in inhibiting Escherichia coli growth. The ripeness stage of WGH significantly affected the antioxidant activity of the extracts. This was attributed to the different polyphenol profiles related to the mechanical stress when the husk opened compared to the closed sample. The antimicrobial activity showed inhibition of E. coli growth. OH-extracts at 96 µg/mL caused the lowest specific growth rate (µmax = 0.003 h−1) and the greatest inhibition percentage (I = 93%) compared to CH-extract (µmax = 0.01 h−1; I = 69%). The obtained results showed the potential of the walnut green husk, principally open husk, as an economical source of antioxidant and antimicrobial agents with potential use in the food industry.

Development of alternative medicinal sources from golden berry, bananas and carrot wastes as antioxidant, cytotoxic and antimicrobial agents

Discovering new medicinal sources from food wastes is a beneficial and valuable way instead of their disposal. Fruits and vegetables waste can be an inexpensive and readily available source of bioactive compounds to be used in pharmaceutical industries. The aim of this study is to highlight the in vitro antioxidant, cytotoxic, and antimicrobial activities of the total extracts of banana peels (Musa acuminate), carrot peels (Daucus carota) and golden berry husk (Physalis peruviana) besides evaluating their in vivo acute and chronic toxicity profiles as well as their antimutagenic activity. Also, we investigated their phenolic and flavonoid contents spectrophotometrically and by HPLC. Results showed that D. carota peels revealed the highest antioxidant activity (29.903 mg TE/g) using DPPH free radical scavenging assay. Cytotoxic outcomes (SulphoRhodamine-B method) showed that the highest cytotoxic activity of M. acuminate peels (IC50: 20.7 μg/mL) was exerted on HEPG2 cell line, where D. carota peels (IC50: 18.8 μg/mL) showed the highest cytotoxic activity on PC-3 cell line. In addition, pH. peruviana husk (IC50: 10.5 ± 1.0 μg/mL) showed a potent cytotoxic activity on HCT-116 that is non-significant from the standard Doxorubicin (IC50: 11.5 ± 0.8 μg/mL). For the antimicrobial activity (agar diffusion assay), most of the total extracts revealed notable activities against all tested pathogens relative to the standards; ciprofloxacin and ketoconazole, specially Ph. peruviana husk that showed a potent inhibitory activity (inhibition zone diameter of 29 mm.) against C. albicans even more than the standard ketoconazole (inhibition zone diameter of 28 mm.). These promising biological activities are mainly related to the high content of flavonoids and phenolic compounds identified and quantified in their total extracts. Moreover, the three extracts proved their in vivo safety on the short and long terms as well as their possible antimutagenic effect on the genotoxicity of the drug cyclophosphamide (CP) in both bone marrow cells and spermatocyte cells.

Application of the thin-layer chromatography method for analysis of plant antioxidant activity

Plants are a rich source of effective non-toxic biologically active substances. Various physicochemical methods of analysis are used for evaluation of plant antioxidant activity. Composition of ethanol extracts of red, yellow and white onion husks, dried rosemary, basil, and chaga were studied by high performance thin layer chromatography (HPTLC) method. The antioxidant activity of the obtained fractions on a chromatographic plate was assessed by subsequent DPPH screening. The extracts red and yellow onion husk and rosemary demonstrated the highest antioxidant activity, variability of the qualitative composition and similarity of antioxidant profiles, while extract of white onion husks did not contain any antioxidant classes. Intensive spots with Rf of 0.13-0.97 were observed along the whole chromatogram track corresponding to red onion husks. It was also found that all tested extract, excepting white onion husk and chaga, contained spots with varying degrees of intensity in the Rf range of 0.96-0.98, which corresponded quercetin Rf value.

In vitro studies of antioxidant, antidiabetic, and antibacterial activities of Theobroma cacao, Anonna muricata and Clitoria ternatea

The present study explored the total phenolic contents, antioxidant, antibacterial, and antidiabetic activities of four Indonesian plants, namely Theobroma cacao pod husk (yellow variant and purple variant of pod husk), Annona muricata leaves, and Clitoria ternatea flower. Antioxidant properties of the extracts and fractions were evaluated using a DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay, and their antibacterial activity against Staphylococcus aureus and Escherichia coli by the microdilution method using resazurin as a colouring agent. The antidiabetic assay was performed by an α-glucosidase inhibitory activity using a glucosidase from Saccharomyces cerevisiae. The results revealed that the pod husk extract of T. cacao of both variants (yellow and purple) had good antioxidant activity and antidiabetic activity with IC50 as of 41.3 and 44.5 μg/mL for the DPPH assay, and 41.6 and 27.7 μg/mL for the α-glucosidase inhibitory assay, respectively. Meanwhile, for antibacterial test, T. cacao pod husk of both variants also possessed the most active extracts with MIC (minimum inhibitory concentration) as of 0.62 mg/mL against S. aureus. Moreover, the FTIR (Fourier Transform Infrared Spectroscopy) analysis suggested the presence of phenolic molecules containing in the extracts. This study revealed that T. cacao pod husk could be a potentially rich source of naturally occurring antibacterial, antioxidant, and antidiabetic medicine.

Antibacterial Properties of Different Husk Extracts of Cocos nucifera (Linn) in South Western Nigeria

Aim: The husk of coconut is part of drupe which have enormous benefit to humanity. However, what constitute the antimicrobial activity has not been fully investigated, and this is the basis for the study.
 Materials and Methods: The husk of coconut collected from local growers subjected to extraction process. The antimicrobial activity was investigated against bacterial strains; Staphylococcus aureus, Escherichia coli, Proteus mirabilis, Salmonella typhi, Enterococcus faecalis, Klebsiella aerogene, Pseudomonas aeruginosa, Streptococcus pneumoniae by agar well diffusion method using n-hexane, ethanol and distilled water as solvents.
 Results: Aqueous extracts of coconut showed inhibitory effect against the different tested bacteria organisms with variable zone of inhibition range 7 to 22 mm.
 Conclusion: The aqueous extracts of coconut exhibited the presence of highly effective bioactive ingredients in these extracts. This can be identified, assay and characterize to be used as synthetic drug which would be available for treatment of bacterial infection.

In vitro Evaluation of the Nutraceutical Potential of Theobroma cacao pod Husk and Leaf Extracts for Small Ruminants.

Some agroindustrial by-products could be used as nutraceutical materials for small ruminants helping with their nutrition while controlling their gastrointestinal nematodes. This study evaluated the potential invitro nutraceutical value of pod husks and leaves of three varieties of Theobroma cacao using two Haemonchus contortus isolates with different polyphenol susceptibility. Leaves and husks from three T. cacao varieties (AZT, CAL and CEY) were evaluated for their bromatological composition, invitro dry matter digestibility and polyphenol content. Acetone:water extracts (70:30) of each plant variety were evaluated using the egg hatch and larval exsheathment inhibition tests, using two isolates (FESC and PARAISO) of H. contortus. Effective concentrations 50% (EC50) were determined for both tests. The role of polyphenols was confirmed using polyvinylpolypyrrolidone. L3 exposed to CAL leaf extract were submitted to transmission electron microscopy. Both plant materials showed a good nutritional value to complement protein-rich diets for small ruminants. Extracts inhibited exsheathment of H. contortus L3 more effectively than the egg hatching, and the leaf extracts were more active than husk extracts in the L3 exsheathment inhibition. The FESC isolate was more sensitive to extracts. Polyphenols blocked exsheathment inhibition of leaf extracts. Structural damage was observed in the sheath and muscles of L3 exposed to CAL leaf extracts. The two T. cacao materials tested showed their potential to be used as ruminant feeds. Extracts affected H. contortus by blocking L3 exsheathment, particularly with the leaf extracts. The in vivo nutraceutical value should be confirmed in small ruminants.

Karakteristik Ekstrak Kulit Biji Kakao (Theobroma cacao L.) sebagai Sumber Antioksidan pada Perlakuan Suhu dan Waktu Maserasi

Cocoa bean husk is a waste of cocoa processing that is large enough and has not been used optimally. Cocoa bean husk can be used as a natural antioxidant by extracting the polyphenol compounds. This research aim to find out the effect of temperature and maceration time on the of cocoa bean husk extracts as a source of antioxidants and to determine the best temperature and time of maceration to produce cocoa bean husk extract as a source of antioxidants. This experiment used a factorial randomized block design with two factors. The first factor was maceration temperature consisting of 30±2?C, 40±2?C, dan 50±2?C. The second factor was maceration time consisting of 24, 36 and 48 hours. The data was analysed by analysis of variant and continued with the Tukey test. The results showed that maceration temperature had a very significant effect, while maceration time had a significant effect on yield, total phenolic, and antioxidant capacity. whereas the interaction between treatments had no significant effect on yield, total phenolic, and antioxidant capacity. The best treatment to produce cocoa bean husk extract as a source of antioxidants is to use a maceration temperature of 50±2?C and a maceration time of 48 hours with a yield characteristic of 2,77 percent, a total phenolic value of 72,35 mg GAE / g, and a capacity antioxidants amounting to 17,45 mg GAEAC / g,
 Keywords : cocoa bean husk, extraction, polyphenol, antioxidant.

Proanthocyanidins with Corrosion Inhibition Activity for AISI 1020 Carbon Steel under Neutral pH Conditions of Coconut (Cocos nucifera L.) Husk Fibers.

Cocos nucifera L. is a palm tree (Arecaceae) with a high economic value. The coconut husk fibers are nonedible, thick, and abrasion-resistant and correspond up to 85% of biomass discarded as solid waste residue. Therefore, the husk fibers are an underexploited byproduct with a high content of extractives of unreported nature. Two varieties of C. nucifera L. husk extracts were investigated to uncover bioactive metabolites and their possible application as a green corrosion inhibitor for carbon steel AISI 1020 under neutral pH conditions. The chemical analysis indicated 3% (w/w) of proanthocyanidins in the husk fibers with a high B-type procyanidin content. The husk fibers’ crude extract showed promising results as an eco-friendly corrosion inhibitor for carbon steel AISI 1020 under neutral pH conditions. Although it formed a film on the metal surface in all tested concentrations (0.4, 0.8, 1.2, and 1.6 g L–1), the highest protective efficiency was shown at a concentration of 1.2 g L–1, determined by electrochemical techniques and mass loss. This was the first comprehensive report on coconut husk fibers’ chemical composition, which was similar between the two varieties with potential for industrial application.

Effect of saline condition and application of rice husk silica extract on lettuce growth in hydroponics

The development of hydroponic vegetable production in coastal areas is faced with the constraints of irrigation water quality that has high NaCl. The purpose of this research is to study the interaction of NaCl concentration in the planting media and the concentration of silica extract of rice husk on the growth of lettuce plants. The study was conducted in April 2019-June 2019 at the greenhouse Palasari-Cibiru Bandung city with altitude + 800 m above sea level. This study used a factorial complete randomized design consisting of 2 factors with three replications. The first factor is the concentration of NaCl (n1 = 0 ppm, n2 = 1,460 ppm, n3 = 2920 ppm, n4 = 4380 ppm, and n5 5850 ppm) and the second factor is the concentration of silica extract of rice husk (s1 = 0 ml l−1, 30 ml l−1, and 45 ml l−1). Growth parameters observed were plant height, number of leaves, leaf area, root length, and plant fresh weight. The results showed that there was an independent effect on the concentration of NaCl on fresh plant weight. In the condition of saline media with a concentration of NaCl 1,460 ppm-2,920 ppm and the concentration of silica extract of rice husk, 30 ml l-1 lettuce plants can grow in good condition.

Characterization of bio-fabricated silver nanoparticles for distinct anti-fungal activity against sugarcane phytopathogens.

Advanced research, development, and application of silver nanoparticles is proceeding in recent times due to their incredible utilization in various fields. Present study was focused on the production, characterization, and antifungal activities of silver nanoparticles (AgNPs). An environment friendly extracellular biosynthetic approach was adopted to produce the AgNPs by using bacteria, fungi, and sugarcane husk. Agents used for reduction of silver to nanoparticles were taken from culture filtrate of plant growth promoting bacteria, Fusarium oxysporum and supernatant extract of sugarcane husk. Nanoparticles were also characterized by scanning electron microscopy (SEM). Synthesis of colloidal AgNPs was observed by UV-Visible diffused reflectance spectroscopy (UV-Vis DRS). Primary peak of surface plasmon resonance band was noticed around 339.782, 336.735, and 338.258 nm for bacterial, fungal, and sugarcane husk produced AgNPs. Structure of all biologically produced nanoparticles were crystalline cubic with nano size of 45.41, 49.06, and 42.75 nm for bacterial, fungal, and sugarcane husk-based nanoparticles, respectively as calculated by Debye-Scherrer equation using XRD. Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of various compounds that aid in the reduction, capping, and stability of AgNPs. The antifungal activity of AgNPs was also investigated for sugarcane fungal pathogens Colletotricum falcatum and Fusarium moniliforme. All nanoparticles exhibit prominent antifungal activities. Maximum zone of fungal inhibition was noticed about 18, 19, and 21 mm for C. falcatum while 21, 20, and 24 mm for F. moniliforme in case of bacterial, fungal, and plant-based nanoparticles (15 ppm), respectively. Best fungal inhibition was observed under application of sugarcane husk based AgNPs. Moreover, biologically produced AgNPs responded better towards the suppression of F. moniliforme in comparison to C. falcatum. Mentioned sources in present study can be ecofriendly nano-factories for biosynthesis of AgNPs and mankind should benefit from their commercial application.

Antioxidant effect of ethanolic onion (Allium cepa) husk extract in ageing rats.

The role of natural antioxidants in preventing of age-relating diseases is evident. The vegetable industry generates a large amount of waste, which is a good source of antioxidants.The aim of the study was the investigation of the antioxidant effect of long-term consumption of ethanolic yellow onion husk extract in ageing laboratory rodents.Twenty male Wistar albino rats were divided randomly into two groups (n = 10): a control group and an experimental group that received ethanolic yellow onion husk extract (2 mL/rat diluted with distilled water; activity of 4.44 µmol-equiv. quercetin) for 188 days. Oxygen radical absorbance capacity and ferric reducing antioxidant power assays were used to determine the total antioxidant capacity of the extract, which amounted to 941.4 ± 32.7 µmol equiv. Trolox/g raw material and 167.4 ± 16.4 µmol-equiv. quercetin/g raw material, respectively. Oral intake of the onion husk extract affected the indicators of the antioxidant system of the liver and the brain but not of the blood and plasma, mainly due to elevations in the activity of catalase and superoxide dismutase in the liver by 44.4% and 79.1%, respectively, and in the brain by three-fold and 79.1%, respectively.The availability, cheapness and high antioxidant potential of onion waste qualifies it a good source of functional ingredients and bioactive substances applicable in the food and pharmaceutical industries.

Synthesis and growth of spherical ZnO nanoparticles using different amount of plant extract

The use of plant extracts has become an interesting ecofriendly method to synthesize and stabilize the different structures nanoparticles (NPs). This work investigated the effect of plant extract as a reducing and stabilizing agent on the growth and morphology of ZnO nanoparticles (ZnO-NPs). Green synthesis and growth of spherical ZnONPs was carried out by co-precipitation method using a Zinc acetate salt and various amounts of Azadirachta indica seed husk extract (20 ml and 40 ml). The synthesized ZnO-NPs were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM-EDX), and transmission electron microscopy (TEM). The FTIR analyses revealed the presence of Phenolic alcohol, amines and carboxylic acid groups and ZnO in synthesized NPs with more intense peaks at higher amount (40 ml) of A. indica extract. Also, structural morphology analyses using SEM revealed uniform spherical shaped particles with diameter from 25 to 60 nm (20 ml of extract) and 19 to 35 nm (40 ml of extract) for ZnO-NPs. The EDX spectral revealed that the required phase of Zn and O was present 69.54% (Zn) and 30.46% (O) at 20 ml of extract, also 73.71% (Zn), 26.26% (O) at 40 ml of extract respectively and confirmed high purity for the synthesized ZnO NPs. TEM revealed spherical shaped NPs with diameter ranging from 28 to 52 nm (20 ml of extract) and 8.2 to 11.9 nm (40 ml of extract) respectively, with a trend reduction in particle size of NPs at higher amount of A. indica seed extract (40 ml) and growth of more uniform particles with no agglomeration. The study showed successful growth of spherical ZnO-NPs with required properties at a higher amount of extract.

Onion husk (Állium cépa) as a promising source of natural antioxidants

The search for new sources of natural antioxidants is an important area of research. The total antioxidant capacities (TAC) of ethanol and aqueous extracts of yellow, red and white onion husks, rosemary and basil were determined by the Oxygen Radical Absorbance Capacity method using fluorometer Fluoroskan Ascent FL and the Ferric Reducing/Antioxidant Power spectrophotometer SF-2000 and expressed in µmol-equiv. Trolox/g of a sample and µmol-equiv. dihydroquercetin / g of a sample, respectively. Ethanol and aqueous extracts of red onion husk demonstrated the greatest TACs and amounted to 709.17±21.68 µmol-equiv. Trolox/g and 2048.83±64.97 µmol-equiv. Trolox/g, and these significantly exceeded the TACs of such popular spices in the food industry as basil and rosemary. TACs of both extracts of yellow onion husk were approximately equivalent to rosemary. Ethanol extracts of red and yellow onion husk demonstrated the greatest TACs and amounted to 2005.64±33.59 µmol-equiv. dihydroquercetin /g and 941.39±65.43 µmol-equiv. dihydroquercetin /g, respectively, and these significantly exceeded the corresponding TACs of basil and rosemary. TACs of aqueous extracts were approximately equivalent to rosemary, but below the TAC of basil. The absence of bright taste and aroma of red and yellow onion husk extracts, high total antioxidant capacity for neutralization of free radicals by both mechanisms of interaction, as well as the availability of raw materials in large scale confirms that this waste of the fruit and vegetable industry is a promising source of natural antioxidants.

Synthesis of ZnO nanoparticles using Theobroma cacao L. pod husks, and their antibacterial activities against foodborne pathogens

Zinc oxide nanoparticles (ZnONPs) with antimicrobial properties have potential applications in the food industry. In the present work, the biosynthesis of ZnONPs was carried out using Theobroma cacao L. pod husk extract. UV-Vis spectroscopy confirmed NP formation by the presence of a peak in the range of 390 - 360 nm. Different parameters affecting the biosynthesis were assessed. A temperature of 28°C and pH of 7 were the best conditions for the formation of small-sized NPs. The antibacterial activity of ZnONPs was evaluated using the resazurin microtiter assay. The minimum inhibitory concentrations of ZnONPs for Escherichia coli and Staphylococcus aureus were 6.25 and 12.5 μg/mL, respectively. ZnONPs were more potent than chloramphenicol, suggesting that they are effective against chloramphenicol-resistant bacteria. Based on scanning electron microscopy and transmission electron microscopy, the ZnONPs were irregular in shape, with an average size of 81 nm. The results of the present work provide a simple, cost-effective, and eco-friendly method for the large-scale production of ZnONPs. Moreover, the study highlights the potential of ZnONPs as an antimicrobial agent that can be applied to food packaging systems, textiles, and medical devices.

Adsorption, kinetics, and thermodynamic studies of cacao husk extracts in waterless sustainable dyeing of cotton fabric

Natural dyes exhibit a low dye uptake when cellulosic fiber dyeing is carried out using a conventional water bath dyeing process. In this research, cotton fabric was exhaust dyed in a microemulsion dyebath containing cacao husk extracts dye and decamethylcyclopentasiloxane (D5) to achieve higher dye exhaustion percentage on cotton fiber, which is an environmentally beneficial dyeing process. The adsorption behavior of cacao husk extract dye in a D5 microemulsion system was investigated under conditions of varied dye mass (1–8% o.w.f), dyeing time (5–500 min), and dyeing temperatures (333–373 K). Kinetic modelling of cacao husk extracts dye/D5 adsorption on cotton fiber was studied by fitting experimental data to pseudo first-order and pseudo second-order kinetics, and the intraparticle diffusion model. Early results indicated that the kinetic model of adsorption of cacao husk extracts dye on cotton fiber followed the pseudo second-order model. Langmuir, Freundlich, and Dubinin–Radushkevich adsorption isotherm models were employed to analyze the adsorption isotherms, and the results showed that the adsorption process fit well with the Langmuir model compared to the Freundlich isotherm. The mean adsorption energy from the Dubinin–Radushkevich isotherm model implied that adsorption of the cacao husk extracts onto cotton was accompanied with a physical process. The values of standard enthalpy (ΔH° > 0), standard entropy (ΔS° > 0), and Gibbs free energy (ΔG° < 0) strongly reflected that the adsorption of the cacao husk extracts onto cotton was thermodynamically favourable and feasible. Thus, waterless dyeing of cotton fabric using a natural dye/D5 system explores a sustainable dyeing technology with higher dye exhaustion percentage.

Inhibitory Effect of Thai Purple Rice Husk Extract on Chemically Induced Carcinogenesis in Rats.

This study investigated the cancer chemopreventive effects of an acidic methanol extract of purple rice husk on chemically induced carcinogenesis in rats. This purple rice husk extract (PRHE) had high polyphenol contents. Vanillic acid was a major phenolic compound in PRHE. Three major anthocyanins found in PRHE were malvidin-3-glucoside, peonidin-3-glucoside and cyanidin-3-glucoside. PRHE was not toxic and clastogenic in rats. The LD50 of PRHE was greater than 2000 mg kg−1 body weight (BW). The oral administration of 300 or 1000 mg kg−1 BW of PRHE for 28 days significantly decreased the number of micronucleated hepatocytes in diethylnitrosamine-initiated rats. The inhibitory mechanisms were associated with the reduction of cytochrome P450 2E1 expression and induction of some detoxifying enzymes in the liver. In addition, treatment with 500 mg kg−1 BW of PRHE for eight weeks did not induce preneoplastic lesions in the liver and colon. It significantly inhibited hepatic glutathione-S-transferase positive foci formation induced by diethylnitrosamine and 1,2-dimethylhydrazine by suppression of hepatocyte proliferation and induction of apoptosis. In conclusion, PRHE did not present toxicity, clastogenicity or carcinogenicity in rats. It exhibited cancer chemopreventive properties against chemically induced early stages rat hepatocarcinogenesis. Anthocyanins and vanillic acid might be candidate anticarcinogenic compounds in purple rice husk.