Agro-waste Materials Research Articles

Lycopene nanoparticles ameliorate the antioxidant, antimicrobial and anticancer potencies of tomato pomace.

Nanoparticles are the basic essential element of nanotechnology and it exhibits characteristic features based on their properties such as size, morphology and other size dependent properties. Their applications on agriculture, food and medicine are widely used nowadays. Agro-waste materials cause a global environmental problem worldwide. Maximizing the benefits of such waste material is a very important issue. The present investigation aimed to use nano-formulation techniques by using polyethylene glycol 8000 to produce nano-lycopene extracted from tomato waste (pomace) as well as evaluation the antioxidant, antimicrobial and anticancer activity of produced lycopene-NPs. The results of antioxidant activity using ABTS and DPPH assays revealed that nano-formulation of Lycopene increases the scavenging activity compared with lycopene. Also, both lycopene and lycopene-NPs showed antibacterial activity against all tested bacteria and antifungal activity against tested fungal species. MIC for lycopene and lycopene-NPs was determined. DNA damage induced by oxidative stress protection analysis indicated that lycopene-NPs has a great potential in DNA damage prevention compared to their respective controls. The MTT assay exhibited cytotoxic activity against three cancerous cell lines, MCF-7, HCT-116 and HepG2. As well as lycopene-NPs biosafety was tested against normal cell lines (BJ-1 and MCF-12F) compared to lycopene.

Statistical Optimization of Poly-β-Hydroxybutyrate Biosynthesis Using the Spent Mushroom Substrate by Bacillus tequilensis PSR-2

Poly-β-hydroxybutyrate (PHB) belonging to the polyhydroxyalkanoates family is a natural polyester used as a biodegradable plastic for various commercial applications. In this study, soil samples from the vegetable oil processing industry were used to screen for PHB-producing bacteria using Sudan black B staining. Among the isolated bacteria, PHB positive PSR-2 isolate was chosen as a potent PHB producer. The phylogenetic tree revealed that the PSR-2 isolate has a high 16S rRNA gene sequence similarity of 99.9% with Bacillus tequilensis. The PHB content of 2.8 ± 0.09 g/L was produced by PSR-2 isolate in 48 h in a nutrient broth medium containing 1% glucose compared to the PHB production of 1.6 ± 0.08% by the reference strain, Bacillus circulans. Taguchi method was used to optimize PHB production using the alkali-pretreated spent mushroom substrate of sugarcane bagasse (SMS-SB) as an additional carbon substrate along with other energy sources. The optimized factors in the contribution of PHB production from the highest- to the lowest-ranking are as follows: alkali-pretreated SMS-SB, glucose, glycerol, peptone, ammonium chloride, and potassium dihydrogen phosphate at 30 oC, pH 7.0, which resulted in the production of 12.4 ± 0.95 g/L PHB was higher than the predicted value of 11.59 g/L. The synthesized PHB was characterized using Ultraviolet–visible spectrophotometry, Fourier transform infrared spectrometry, differential scanning calorimetry, thermogravimetric analysis, nuclear magnetic resonance spectroscopy, and gas chromatography-mass spectrometry. The results revealed the presence of hydroxyl (–OH), methyl (–CH3), methine (=CH–), methylene (–CH2–) and ester carbonyl (>C=O) groups, which confirmed the PHB structure. Thus, alkali-pretreated SMS-SB plays a significant role as an energy substrate for the production of PHB. This gives the knowledge to utilize cost-effective lignocellulosic agro-waste materials as a feedstock for the sustainable production of biodegradable PHB for many biomedical applications.

Alternative adsorbent to remove Cr (VI) ions from industrial wastewater

Heavy metals which are discharged from industries in the environment with wastewater causes serious problems for the living organisms. To save the water bodies from the heavy metal contamination, many treatment processes are there. But most used is Adsorption processes where Activated Carbon is used as Adsorbent. As the activated carbon is costly, the treatment is expensive. So, low-cost alternate adsorbents are to be identified in the present scenario. The locally available agro waste material namely Teak Leaves (botanical name is Tectona Grandis) is used as low-cost adsorbent Teak leaves (TL) with pretreatment have been used to study for their potential use to remove chromium (VI) from wastewater by Adsorption. Contact time, Adsorbent dose, pH, initial Cr (VI) ions concentration and particle size have been studied for batch process. The optimum pH, agitation time, Cr (VI) ions conc. adsorbent dose and particle size were found 2.0, 75 minutes, 175 milligrams/l, 25 gm./l and 150 – 300 microns respectively at the room temperature (30 ± 2° C) and achieved 69.1 % to remove Cr (VI). Whereas, the powdered activated carbon (PAC), the removal was 78% at optimum conditions 2.0, 60 min, 125 mg/l, 15 gm/l and <75 micron respectively. The adsorption equilibrium data was used to fit into, Freundlich, Langmuir and modified Freundlich isotherm. But Freundlich isotherm fitted well compared to other two. A distinct advantage of TL as bio-sorbent is that these are locally and easily available agricultural waste and can be used with minor chemical treatment. This process is cost effective and eco-friendly.

Physicomechanical Properties of Rice Husk/Coco Peat Reinforced Acrylonitrile Butadiene Styrene Blend Composites.

Utilizing agro-waste material such as rice husk (RH) and coco peat (CP) reinforced with thermoplastic resin to produce low-cost green composites is a fascinating discovery. In this study, the effectiveness of these blended biocomposites was evaluated for their physical, mechanical, and thermal properties. Initially, the samples were fabricated by using a combination of melt blend internal mixer and injection molding techniques. Increasing in RH content increased the coupons density. However, it reduced the water vapor kinetics sorption of the biocomposite. Moisture absorption studies disclosed that water uptake was significantly increased with the increase of coco peat (CP) filler. It showed that the mechanical properties, including tensile modulus, flexural modulus, and impact strength of the 15% RH—5% CP reinforced acrylonitrile-butadiene-styrene (ABS), gave the highest value. Results also revealed that all RH/CP filled composites exhibited a brittle fracture manner. Observation on the tensile morphology surfaces by using a scanning electron microscope (SEM) affirmed the above finding to be satisfactory. Therefore, it can be concluded that blend-agriculture waste reinforced ABS biocomposite can be exploited as a biodegradable material for short life engineering application where good mechanical and thermal properties are paramount.

Scale-up process for xylose reductase production using rice straw hydrolysate

Xylose reductase (XR), an industrially important enzyme, catalyzes the hydrogenation of xylose into xylitol. Xylitol, a polyol sugar, has tremendous applications in different industries due to its significant properties. XR is mainly produced from yeasts and molds, and limited studies have been reported on bacteria. The present study explores the potential of newly isolated bacteria, i.e., Pseudomonas putida BSX-46 for XR synthesis through process scale-up by tailoring its nutritional and cultural requirements. A simple media containing only four ingredients was designed for the production of XR in a short incubation time of 24 h. A process for pretreatment of rice straw was developed to achieve hydrolysate with a good amount of xylose (140 g/kg of rice straw). The enhanced XR production of 213.14±0.47 IU/mg of cells was achieved at bioreactor level using waste rice straw hydrolysate as compared to 94.26±0.62 IU/mg of cells at flask level. The developed bioprocess using efficient bacterial source and economical raw material would provide a low-cost substitute for XR production from xylose-based agro-waste materials at the industrial level.

Agro-Waste Generated Pd/CAP-Ash Catalyzed Ligand-Free Approach for Suzuki–Miyaura Coupling Reaction

We converted agro-waste Custard Apple Peels (CAP) to ash via thermal treatment, on which Pd(OAc)2 was immobilized easily that produced a low-cost, highly efficient Pd/CAP-ash catalyst. The prepared catalyst was fully characterized by using FT-IR, SEM, EDX, XRF, DSC-TGA, BET, HR-TEM, and XPS techniques. The Pd/CAP-ash catalyst was conveniently applied for the Suzuki–Miyaura coupling reaction under external base free and ligand-free conditions in an aqueous-organic solvent to produce biphenyls in good to excellent yields. The main attraction of our protocol an application of palladium-supported agro-waste material which is easily recoverable and recyclable provides mono and bis-coupled derivatives in a short reaction time.

Low-formaldehyde emission composite particleboard manufactured from waste chestnut bur

Chestnut bur is an agro-waste material generated in the chestnut production. It is a tannin-rich lignocellulosic material which might be a promising raw material for low-formaldehyde composite particleboard production when using urea–formaldehyde (UF) as bonding adhesive. In this study, the characteristics of chestnut bur were analyzed to assess its application value for composite panel. Five-type particleboards were manufactured from the mixture of chestnut bur/poplar particles with the weight ratios of 0/100, 25/75, 50/50, 75/25 and 100/0, UF resin was used as bonding adhesive. The effects of the addition amount of chestnut bur on the physical, mechanical properties and formaldehyde emission of particleboard were studied. The results showed as follows: (1) chestnut bur showed low cellulose, hemicelluloses and lignin contents, but high extractives and ash contents compared with poplar wood. Chestnut bur and poplar wood had the similar fiber morphology. (2) Composite board with relatively good performances could be manufactured with mix particles of chestnut bur and poplar wood. With the increasing of chestnut bur content, the mechanical properties of the composite board decreased, whereas the dimensional stability increased. (3) The total phenol content in the chestnut bur was as high as 13.79%. The phenolic substance in the chestnut burs could react with free formaldehyde. Hence, the free formaldehyde emission of particleboard was effectively reduced. In summary, waste chestnut bur is a suitable material which can not only be utilized as the base material, but also a natural free formaldehyde scavenger for composite particleboard production.

Preclinical assessment of stem of Nicotiana tabacum on excision wound model

Agro-waste material derived from N. tabacum has shown enormous potential antioxidant and antimicrobial activity. Hence in the present study, we investigated the wound healing efficacy of ethanolic extract of stem of Nicotiana tabacum on wistar rat model. Ethanolic extract prepared from defatted stem was to check various phytochemicals using spectrophotometric and chromatographic technique. The antioxidant potential was determined by FRAP and Reducing Power assay in extract. Cytotoxicity of extracts was determined using mouse fibroblast L929 cell lines by MTT assay. In vivo angiogenic activity was observed on chick chorioallantoic membrane (CAM) model by observing blood vessels formation and its branching. In vivo wound healing activity was observed on excision wounds in rat model by quantifying percentage of wound contraction, antioxidant activity and histopathology studies. From the present study, polyphenols, tannins and alkaloids were found to be determined in the ethanolic extract by means of spectrophotometric and chromatographic analysis against standards. Antioxidant assay revealed maximum antioxidant potential in ethanolic extract. Cytotoxic effect of extract has not been shown on L929 cell line. From CAM model, extract has shown growth of blood vessels formation at concentration of 480 µg/ml. Topical application of extracts on excision wounds, revealed wound healing activity i.e. 98.7% ± 0.002 on 14th day as well as enzymatic activity (SOD, CAT, GST) and non enzyme content (GSH and Lipid peroxidation) has been found to be high in granulated tissue. Hisopathological studies confirmed the re-epithelization in skin wounds. It can be concluded that stem of N. tabacum can be used as herbal remedy in wound healing process as a topical application.

Recent insights, applications and prospects of xylose reductase: a futuristic enzyme for xylitol production

Xylose reductase (XR) is an intermediate inducible enzyme of xylose metabolism responsible for the reduction of xylose into xylitol. It is an intracellular enzyme present in various facultative bacteria, yeasts, molds and algae in their cytoplasm. The active site of enzyme is polar in nature which is responsible for acid–base catalysis. The enzyme is folded into (β/α)8 barrel and its substrate specificity is through C-terminal region. XR is an emerging industrially important food enzyme due to its major application in production of xylitol. Xylitol has shown remarkable applications in other industrial sectors such as food, biofuels, pharmaceutical, medical, odontological, textiles and cosmetics. This enzyme has been purified and characterized to understand its physico-chemical properties and stability. Further, robust microbial strains with tolerance towards high substrate concentration and toxic compounds are required to be developed for successful exploitation of XR at industrial level using agrowaste materials.

Adsorption of textile industry effluent in a fixed bed column using activated carbon prepared from agro-waste materials

Abstract Activated carbon prepared from agro-waste material i.e. green coconut shell and bamboo using ZnCl2 as an activation agent in an adsorption column (fixed bed) was studied for the treatment of textile industry effluent. The experiment with the fixed-bed column was performed by different process parameters such as 200, 400 and 600 mg/L as different initial concentration of dye, at different bed heights of 100 mm, 200 mm, and 300 mm, and 10, 15, and 20 mL/min as different flow rates. The findings demonstrated that both breakthrough and exhaust times increase, with the height of the bed being increased, but decrease with the concentration of the dye inlet. The breakthrough point was found to depend upon the bed height and flow rate. The maximum uptake capacity was obtained when a 200 mm bed depth was used at an inlet concentration of dye 200 mg/L with a flow rate of 15 mL/minute. It was observed that the bamboo activated carbon BAC has high carbon content, and has a high potential for dyes removal and may become capable substitutes for costly activated carbon. The adsorption capacities of BAC, GCSAC are at par with respect to each other, the overall process scheme may become economical as these materials are available as wastes and practically free of cost.

Comparative studies of removal of hazardous dyes, methylene blue (MB) and malachite green (MG) from solutions by low cost activated carbon

The removal of two hazardous dyes, MB and MG newly synthesized economic activated carbon. The adsorbent was synthesized from an agro waste material. The activated carbon has been characterized by XRD, FTIR, SEM, and surface area. A comparative study of the removal of selected dyes was reported. The process of removal for both the dyes is optimized for important parameters. It has been observed that removal of the dyes is maximum in alkaline range of pH. Both for MB and MG, the removal is controlled by first order kinetics. Mass transfer studies for both the dyes have been reported and the values of coefficient of mass transfer are found to be 2.25×10-5 cm/s and 1.92 cm/s respectively at 30°C. The rates of transfer of dyes onto the adsorbent surface were significant both the cases. The process of removal is endothermic and in both the cases higher temperature favoured the removal. Equilibrium data fitted Freundlich adsorption isotherm and the values of constants are found to be 0.59 and 3.01 mg/g for the removal of selected dyes. The results show suitability of the synthesized material for both the systems and can serve as baseline data for dyes removal.

Uncontaminating Concrete Mix Using Sugarcane Bagasse Ash: A Review on its Hardened Properties

Concrete is one among the most used material for construction other than water. Cement is the important constituent of concrete. During the production of cement high amount of carbon dioxide is emitted and is responsible for global warming. High amount of cement production is causing environmental problem. Use of agro-waste materials like bagasse ash, increases the strength characteristics of concrete and also causes proper disposal of the waste materials. In this paper, use of sugarcane bagasse ash, an agro-waste product, as a partial replacement of the cement in concrete mix and its effect on the strength parameters of concrete are also identified on the basis of compressive strength, spilt tensile strength and flexural strength. This waste usage is very economical and also have positive impacts on minimizing environmental pollutions.

Physical and Mechanical Study of Palm Oil Fuel Ash (POFA) based Geopolymer as a Stabilizer for Soft Soil

Construction of structures on soft soil is a challenging task and considered as one of the biggest concerns in geotechnical engineering. Binders that are environmentally friendly such as fly ash based geopolymer have been explored widely. In this study, the agro-waste material, Palm Oil Fuel Ash (POFA) was used to produce an environmentally friendly geopolymer binder to be used in soft soil stabilization. POFA was used in three ratios; 10%, 20% and 30% of dry weight of soil to produce geopolymer. Sodium hydroxide (NaOH) was used as an alkali activator at 12 molarity along with sodium silicate (Na2SiO3). Physical properties of soil (Atterberg Limits, Plasticity Index, and Linear Shrinkage Limit) and compaction assessment; before and after mixing with the geopolymer binder were investigated. The studied soil was classified as an inorganic high plasticity silt (MH), according to the Unified Soil Classification System (USCS). From compaction results; optimum moisture content (OMC) values showed a decreased pattern from 24.7% to 17.5%; and maximum dry density (MDD) increased from 1.37 Mg/m3 to 1.73 Mg/m3 for geopolymer with POFA ranging from 0% to 30% of the dry weight of soil, respectively. The optimum dosage of POFA based geopolymer was found to be 30% according to all tests mentioned. These properties suggest the potential use of the agro-waste based geopolymer binder to stabilize the soft soil.

Removal of fluoride with rice husk derived adsorbent from agro waste materials

Elimination of fluoride from water sample is an imperative stimulus for the betterment of society. Based on WHO policy, the fluoride level superior than 1.5 miligram/litre causes dental and bone scarcity to living entities. In order to prevent these issues, the proper deflouridation technique was chosen. In the present investigations highlighted the elimination percentage of Fluoride from water with the aid of low-cost material, rice husk. Various physical and chemical deflouridation methods were developed to treat high concentrations of fluoride in ground water. Those deflouridation methods need to be built which this will be cost-efficient, and biodegradable. Rice husk is used to detoxify fluoride-rich water and making it safe for human use. 0.5 g/100 mL of adsorbent accomplished 87% of fluoride removal.

Investigation on sliding wear behaviour of walnut shell powder (WSP) filled polyester composites using finite element method

Walnut shell powder (WSP) is an agro-waste material generated in all over the world, primarily has no important use. In this study, an attempt has been made to utilize this waste as reinforcement in particulate filled polymer composite. Such polymer composite samples are fabricated with varying proportions of WSP filler content and unsaturated polyester resin. WSP-polyester composite samples are subjected to dry sliding wear test by pin-on-disc test machine according to L9 orthogonal array of Taguchi’s experimental design. The impact of different input factors on the wear behaviour of the WSP-polyester composites has been analyzed and also the best possible combination of these factors for the minimum specific wear rate is determined. Commercially available FEM-based simulation software is also utilized to assess the specific wear rate of the WSP-polyester composites. The wear values predicted by ANSYS 19.R2 are validated with the measured data and found to be in with close agreement.

Morphological investigation and mechanical behaviour of agrowaste reinforced aluminium alloy 8011 for service life improvement

Aluminium composite materials are beneficial in most engineering applications, most notably, because of their lightweight to strength ratio amongst many others. This study reports the reinforcement of aluminium alloy 8011 with cow horn and corncob in varying weight percentages of 5wt%, 10wt%, 15wt% and 20wt%. This study adopted the Stir casting method based on availability and cost-effectiveness as the cheapest method amongst others. The developed composite materials were in eight different samples alongside one control sample of the aluminium alloy base material. The samples used for this experimental study were tested for tensile strength, hardness and microstructural analysis. The outcome of the study shows that the sample with 20wt% of cow horn reinforcement gave the best-improved properties in terms of yield strength, ultimate tensile strength (UTS) and hardness with percentage improvement of 57%, 52.6% and 54.4% respectively. Hardness was also improved with 52.6% over the control sample with the 15wt% cow horn reinforced sample. Cow horn of 10wt% reinforcement improved the material by 61%. The results shown have justified the relevant effect of agro-waste materials in composite development.

Removal of heavy metal ions from water using adsorbents from agro waste materials

When discharged without adequate treatment into water resources, hazardous metal ions found in industrial wastewater influence the risk to human and environmental health. Low-cost adsorbents with a high metal-binding potential are widely used for heavy metal removal. Intrinsic physico-chemical structural features of adsorbents significantly affect their potential for adsorption. The influence of physico-chemical properties on the adsorption capacity is comparable for all three metal cations namely Cu2+, Co2+, and Zn2+. Acidic surface functionalities were bound with Cu2+ and Co2+. Carboxylic groups were involved in adsorption of Cu2+ and Zn2+ whereas lactonic groups were interact with Zn2+ and convert into complexation. The pH effect demonstrated a dramatic increase in adsorption efficiency by rising the solution pH from 3 to 6. It was proven that adsorbent could be used as an effective adsorbent for removal of Ni(II) ions from water solutions as an alternative to commercial activated carbons.

Hyper Production and Eco-Friendly Bleaching of Kraft Pulp by Xylanase From Bacillus pumilus SV-205 Using Agro Waste Material

Hyper production of an extra cellular, alkali stable, cellulase free and thermostable xylanase have been produced from Bacillus pumilus SV-205 using wheat bran as a substrate under solid state fermentation. Enzyme production under optimized conditions enhanced the production level from 4510 to 65,130 ± 1000 IU/g dry substrate, which was 14.4 fold as compared to production under un-optimized conditions. The application of crude xylanase was investigated in pulp bio bleaching. The bio-bleaching of kraft pulp with xylanase was the most effective at an enzyme dose of 12.5 IU/g oven dried pulp, pH 10.0 and 120 min incubation at 60 °C. Under the optimized conditions, xylanase pre-treatment reduced Kappa number by 0.8 points and increased brightness by 1.08 points as compared with the control. The pre-treatment of pulp with xylanase resulted in 19.01% reduction in chlorine consumption by maintaining the same brightness as in control. These results clearly demonstrated that the B. pumilus SV-85S xylanase was effective as a pulp bio-bleaching agent. The decrease in chlorine consumption by pre-treatment of pulp with xylanase apparently made the bio-bleaching process not only economical but also eco-friendly. The xylanase from B. pumilus SV-205 exhibit remarkable properties which are suitable for application in paper pulp bleaching and an elevated production of xylanase by B. pumilus SV-205 under solid state fermentation over wheat bran, a cheap and easily available agro-residue would apparently reduce the enzyme cost substantially.

Modified wheat straw-derived graphene for the removal of Eriochrome Black T: characterization, isotherm, and kinetic studies.

A cost-effective and environment-benign adsorbent was prepared from an abundant agro-waste material. Wheat straw was reduced to graphene and then modified by crosslinking to epichlorohydrin. During the conversion process of wheat straw to graphene, the specific surface area increased more than 100 times (from 4 to 415 m2 g-1). The adsorption efficiency of raw wheat straw, graphene nanosheets, and modified graphene against Eriochrome Black T (EBT) were 8.0, 34.7, and 74.4%, respectively. The modified graphene was further investigated for the effect of environmental condition, i.e., pH (3 to 11), EBT concentration (25-100 mg L-1), adsorbent dosage (0.25-0.75 g L-1), contact time (5-60 min), and solution temperature (30-60 °C). The dye removal remained at a high level under a wide range of pH from 3 to 9. The EBT removal decreased from 87.3 to 54.5 by increasing dye concentration and increased from 38.2 to 85.4% by increasing adsorbent dose in the studied ranges. Dye removal also increased by mixing time from 5 to 30 min, whereas a slight drop was observed by continuing agitation up to 60 min. Conducting experiments at various temperatures revealed an endothermic process. Pseudo-first-order and pseudo-second-order models were adequate to represent the adsorption kinetics. Isotherm models suggest a multilayer adsorption of EBT molecules on heterogeneous modified graphene surface with a maximum adsorption capacity of 146.2 mg g-1. The present work demonstrated that the modified graphene obtained from available and low-cost agro-wastes could be used effectively as adsorbent against EBT from aqueous media.

A novel non-enzymatic glucose sensor based on gold-nickel bimetallic nanoparticles doped aluminosilicate framework prepared from agro-waste material

Functionalizedporous nanomaterials have been introduced as novel substrates with high surface area and large porosity for the construction of efficient catalysts in sensors. In this regard, nano X zeolite (NX), as a kind of aluminosilicate framework material, can be used as a hosting material for nanocatalysts in the design and fabrication of electrochemical sensors. Herein, a sensor based on multi-walled carbon nanotube (MWCNT) and NX material as a substrate for AuNi bimetallic nanoparticles obtained from agro-waste stem sweep was fabricated to detect nanomolar concenteration of glucose. The catalyst has provided a desired analytical performance for the glucose sensor with low limit of detection (0.063 µM) in the linear range of 1–1900 µM and sensitivity of 662.93 µA mM−1. The results depend on the presence of NX in the sensor and confirm the preference of a porous host existence for the AuNi catalyst in the sensing process. In AuNi/NX/MWCNT electrocatalyst, the disaggregation of Au nanoparticles by decorating on sacrificial Ni and the creation of abundant active sites through NX make the acceptable results for non-enzymatic detection of glucose in the human serum samples.