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Showing papers in "Journal of Agricultural Chemistry and Environment in 2019"


Journal ArticleDOI
TL;DR: In this paper, a pot experiment was conducted to investigate the effect of cow dung, rice husks, calcium chloride and gypsum on soil reclamation and compare the effect the organic and inorganic amendments on soil Reclamation during the period of 5th March to 20th April 2017.
Abstract: A pot experiment was conducted to investigate the effect of cow dung, rice husks, calcium chloride and gypsum on soil reclamation and compare the effect of organic and inorganic amendments on soil reclamation during the period of 5th March to 20th April, 2017. The experiment was laid to fit a completely randomized design (CRD) with seven treatments [Reference soil (T0), Cow dung (T1), Rice husk (T2), Gypsum (T3), Calcium chloride (T4), Cow dung + Rice husk (T5) and Gypsum + Calcium chloride (T6)] each having three replications for this experiment. After incubation (45 days), the laboratory investigation was carried out in the Soil, Water and Environment Discipline, Khulna University, Khulna, Bangladesh. Results indicate that the individual or combined effect of gypsum (T3) was more effective in changing EC and SAR. Gypsum application in combination with calcium chloride (T6) improved the soil chemical properties by reducing the EC. Among the treatment, calcium chloride (T4) had a remarkable effect in reducing sodium adsorption ratio and gypsum had a remarkable effect in reducing pH. Cow dung (T1), rice husk (T2), combination of cow dung and rice husk (T5) were less effective to reduce EC, pH and SAR. It’s measured for soils of different soil amendments varied significantly (P < 0.05) and also with the reference soil.

11 citations


Journal ArticleDOI
TL;DR: The major concern of food and feed industries is the contamination of food products and animal feed supplies by these mycotoxins, which are capable of causing health hazards and death for both human and animals by effecting mammalian cells, causing a number of problems in normal cell function and a wide variety of clinical symptoms of diseases as mentioned in this paper.
Abstract: Mycotoxins are toxic secondary metabolites produced by fungus kingdom. Fungi (molds) under aerobic and optimum conditions of humidity and temperature consume nutrients for proliferation and mycotoxin production (secretion). There are seven major groups of mycotoxins produced by different species of toxigenic fungal genus. Mycotoxins production from these toxigenic fungi depends on the surrounding intrinsic and extrinsic environments. These seven mycotoxins groups that contaminate grains, foods and animal feeds are: Aflatoxins, Trichothecene, Ochratoxins, Ergot alkaloid (Ergolin), Fumonisins, Patulin, and Zearalenone. These mycotoxins are capable of causing health hazards and death for both human and animals by effecting mammalian cells, causing a number of problems in normal cell function and a wide variety of clinical symptoms of diseases. These mycotoxins are varied in their toxicity depending on the infected host (human or animal) and the host susceptibility (immunity). The major concern of food and feed industries is the contamination of food products and animal feed supplies by these mycotoxins. Worldwide Health Organization (WHO), and Food and Agriculture Organization (FAO) are responsible to regulate the acceptable (tolerable) levels of these mycotoxins in grains, food and feed supplies to ensure the safety and health for both human and animals. Understanding fungal ecology and factors that affect fungal proliferation and mycotoxins production by these toxigenic fungi in agriculture crops as raw materials for both human food and animal feed products, plus understanding the chemistry and property of these mycotoxins, methods of detection, illness symptoms, and comply with regulatory guidance established by World Health Organization (WHO)/Food and Agriculture Organization (FAO) are key factors to prevent or minimize foods/feeds contamination and the toxicity of these mycotoxins for both human and animals health, plus reducing economical loss.

5 citations


Journal ArticleDOI
TL;DR: One of the most important recently used methods is push-pull which consists of semiochemicals called Herbi-vore-Induced Plant Volatiles (HIPVs) which has been used to pre-vent pest and attract natural enemies.
Abstract: Biological control through habitat management leads to sustainable insect pest control. Different types of land composition such as multiple landscapes, patchiness of landscapes enhance the natural enemies which ultimately lead to control of insect pest. Plant characteristics such as flower shape, flower color and blooming period ensures excess food for natural enemies like nectar and pollen. Moreover, some agricultural practices such as tillage, crop rotation, and intercropping influence the natural enemies especially parasitoid and preda-tors. Consequently, they increase longevity and fecundity of parasitoid and predator that help to control insect pest. One of the most important recently used methods is push-pull which consists of semiochemicals called Herbi-vore-Induced Plant Volatiles (HIPVs). This compound has been used to pre-vent pest and attract natural enemies.

5 citations


Journal ArticleDOI
TL;DR: In this article, the authors used an atomic absorption spectrophotometer to determine the metal ions concentrations absorbed in the plants and found that all the vegetables absorbed significant amounts of the metal ion.
Abstract: The effect of anthropogenic activity relating to industrial and economic development has had a detrimental impact on the environment and human health, and hence the need for continued research. Five common African vegetables—Murraya koenigii, Ocimum gratissimum, Amaranthus hybridus, Capsicum annuum and Moringa oleifera were used to study absorption of Lead, Cadmium, Cobalt and Zinc from soils inoculated with metal ions. 0.1 M and 0.5 M solutions of the metal ions were used in the inoculation. Each of the plants was collected in the first instance at 8 weeks, and then at 10 weeks of inoculating. Atomic Absorption spectrophotometer was used to determine the metal ions concentrations absorbed in the plants. Cd2+ was most and Moringa oleifera the least absorbed of the four metal ions, with a highest value of 34.801 ± 0.805 mg/kg occurring in Capsicum annuum. Co2+ was the least absorbed of the four metal ions, Amaranthus hybridus showed highest absorption of Co2+ with mean absorption values of 5.566 ± 0.324 mg/kg and 5.670 ± 0.210 mg/kg for 0.1 M and 0.5 M solution of Co2+ respectively. Ocimum gratissimum absorbed Pb2+ most with the highest mean absorption of 5.290 ± 0.180 mg/kg and 6.354 ± 0.366 mg/kg for 0.1 M and 0.5 M respectively. Absorption increased as the concentration of the inoculant solution increased for all the plants, and decreased on moving from 8 weeks’ to 10 weeks’ for all the plants except Moringa oleifera. This could as a result of Phytovolatilization against the report of Padmavathiamma and Li, 2007 [1] that phytovolatilization occurs in As, Hg and Se. Ocimum gratissimum showed highest absorption with the mean value of 9.334 ± 0.312 mg/kg, when the inoculants concentration increased to 0.5 M, Capsicum annuum showed highest absorption with mean absorption value of 9.916 ± 0.614 mg/kg at 10th week. Also absorption increased as the concentration of the inoculant solution increased, and also on moving from 8 weeks’ to 10 weeks’ for all the plants. From the results obtained, all the vegetables absorbed significant amounts of the metal ions. This raises a lot of health concern about the vegetables consumed in most developing countries like Nigeria where vegetables are grown anywhere, without any consideration of the environment.

5 citations


Journal ArticleDOI
TL;DR: Pyrichalasin H isolated from Pyricularia grisea, a pathogen infecting B. eruciformis (signal grass) was shown to be phytotoxic and fungicidal to Colletotrichum fragariae and this is the first report of antifungal activity of pyrichAlasin H against phytopathogens.
Abstract: Brachiaria eruciformis (sm.) Griseb, locally known as “signal grass”, is a common weed in lawns and turfs in Mississippi, USA. During late spring and early summer months, leaves of B. eruciformis are infected with a fungus causing necrosis. The infected leaves ultimately turn brown and wither. As part of our search for potential new natural product-based agrochemicals, we studied this plant pathogen in order to investigate phytotoxic and fungitoxic metabolites produced by the fungus. The causative fungus was isolated from an infected leaf of B. eruciformis, cultured in potato dextrose agar plates and identified via molecular techniques as Pyricularia grisea. A phytotoxic compound was isolated from Czapek-Dox broth liquid culture medium and identified as pyrichalasin H by spectroscopic techniques. Pyrichalasin H was toxic to the fungal plant pathogen Colletotrichum fragariae in a TLC bioautography assay and phytotoxic to two monocot and one dicot plants. This is the first report of antifungal activity of pyrichalasin H against phytopathogens. Pyrichalasin H isolated from Pyricularia grisea, a pathogen infecting B. eruciformis (signal grass) was shown to be phytotoxic and fungicidal to Colletotrichum fragariae.

5 citations


Journal ArticleDOI
TL;DR: In this paper, the degradation of starch-based bioplastics was investigated in the presence of weather parameters such as rainfall, temperature, relative humidity, sunshine intensity and sunshine hours.
Abstract: The threat posed by plastics to the environment has prompted the development of bioplastics. Starch plasticized by glycerol is a key renewable resource in the production of high-quality bioplastics. Previous studies have availed information on the mechanical quality of starch-based bioplastics however there is limited information about their degradation pattern in the natural environment which this research presents. Bioplastics were buried in holes in loam sandy soil and weekly photographic data and weight were collected to reveal the effect of degradation. Weather parameters of rainfall, temperature, relative humidity, sunshine intensity and sunshine hours were recorded to establish influence of weather on degradation. A control set up in the laboratory was used to compare the results. Over time the tests revealed that as the hydrophilic enzymes break down the bioplastic, its weight initially increases (up to 87%) due to absorption of moisture and after saturation, the bioplastic is disintegrated which initiates decomposition and the bioplastic weight is steadily reduced. Degradation was further enhanced by invasion of soil organisms like worms, termites among other soil microbes. Rainfall (r = 0.857) increased the moisture in the soil which initially increased the weight of the bioplastic up to a point when the hydrophilic enzymes set into breakdown the bioplastic then the weight started to drop. This was the same case for relative humidity (r = ﹣0.04) however; the sunlight intensity (r = 515) and hours of illumination indirectly affect the process by influencing microbial activity. An increase in the sunshine intensity increased the activity of soil organisms up to a point beyond which increased exposure caused the organisms to burrow deeper in the soil. Increase in microbial activity increased the rate of degradation of the buried bioplastics which took five to ten weeks to fully decompose (98.3%). The reduced time of degradation means that starch-based bioplastics have a high potential as sustainable substitute for petroleum-based plastics.

5 citations


Journal ArticleDOI
TL;DR: In this paper, the authors examined the possibility of wood biomass for preparing organic soil and constructed reproducible and stable organic standard soil from base soils and additive materials based on the recommended values of the soil fertility index (SOFIX).
Abstract: Possibility of wood biomass for preparing organic soil was examined to construct reproducible and stable organic standard soil. Seven organic soils were constructed from base soils and additive materials based on the recommended values of the soil fertility index (SOFIX) (total carbon ≥ 25,000 mg/kg, total nitrogen ≥ 1500 mg/kg, total phosphorus ≥ 1100, and total potassium of 2500 to 10,000 mg/kg). Base soils were prepared from two types of wood biomass (big- and small-sized wood chips) at 50%, 60%, and 70% (v/v) and other organic materials such as peat moss, black soil, and mountain soil. Additive materials (soybean meal, oil cake, cow manure, and bone meal) were amended into all organic soils at the same amount. Incubation experiment showed that bacterial biomass in all organic soil was greater than 6 × 108 cells/g-soil after addition of 30% of water content for 1 week. In addition, polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) analysis resulted in a stable bacterial diversity of the organic soil prepared from the small size wood chip at 70%. Chemical properties of all organic soils were within the recommended values of SOFIX. The plant cultivation experiment showed that fresh Brassica rapa var. peruviridis weights in the organic soils with 50%, 60%, and 70% of small-sized wood chip were 5%, 16%, and 27% higher than that of the chemical fertilizer-amended soil. The organic soil with 70% of small wood chip was the best in the seven organic soils in this study.

4 citations


Journal ArticleDOI
TL;DR: Murraya koenigii, Ocimum gratissimum, Solanum nigrum, Zingiber officinale can be used in iodine biofortification using KI and KIO3 at concentration The overall result may be very significant, when it is considered that Iodine is a micronutrient, with a daily intake requirement of 100 - 150 μg/kg.
Abstract: Iodine Deficiency Diseases (IDDs) occupy important positions in the health problems of developing countries. Salt Iodisation has been the common approach to solving these problems. However, apart from the problems of lack of compliance by salt manufacturers, and inculturation of the consumers, health conditions aggravated by high salt intake by humans have become increasingly relevant. These problems can be eliminated if the commonly produced and consumed plants are fortified with Iodine. The prospects are in the inclusion of Iodine-containing compounds in the inorganic fertilizers used by farmers. In this study, Potassium Iodide and Potassium Iodate were used as inoculants. Five different concentrations—0.1 M, 0.2 M, 0.3 M, 0.4 M, and 0.5 M of Potassium Iodide and Potassium Iodate solutions were used to inoculate the soils on which the following edible African plants were planted: Murraya koenigii; Ocimum gratissimum; Cucurbita pepo; Solanum nigrum; Amaranthus hybridus and Abelmoschus esclentus, Corchorous olitoruis, Solanum lycopersicum, Zingiber officinale, Telfairia occidentalis, Talinium triangulare, Solanum melongena. Controls were also planted. After 14 days, alkaline dry ash method was used to determine the Iodine concentrations in the plants. The results showed that Murraya koenigii showed the highest absorption of Iodine 6.90 mg/kg at 0.3 M using KI, followed by Amaranthus hybridus 6.40 mg/kg at 0.1 M. Solanum nigrum, Ocimum gratissimum and Zingiber officinale also showed good absorption. Other plants except Murraya koenigii, Ocimum gratissimum, Solanum nigrum and Zingiber officinale showed very low tolerance to KI absorption. The result also showed that Telfairia occidentalis showed the highest absorption of iodine 8.20 mg/kg at 0.2 M of KIO3 followed by Cucurbita pepo 6.40 mg/kg at also 0.2 M of KIO3. Murraya koenigii, Ocimum gratissimum, Solanum nigrum, Zingiber officinale also showed good absorption of KIO3. Some of the plants were not able to tolerate the absorption at higher concentration for both KI and KIO3. All the plants were poisoned at concentration of 0.5 M for both Ki and KIO3. Murraya koenigii, Ocimum gratissimum, Solanum nigrum, Zingiber officinale can be used in iodine biofortification using KI and KIO3 at concentration The overall result may be very significant, when it is considered that Iodine is a micronutrient, with a daily intake requirement of 100 - 150 μg/kg. It can be seen that there is hope in achieving this kind of biofortification.

3 citations


Journal ArticleDOI
TL;DR: In this article, the presence and concentration of persistent organochlorine pesticides (OCPs) residues in cow milk from Ekiti State University Agricultural farm in Ado-Ekiti, Nigeria was determined.
Abstract: Background: The study determined the presence and concentration of persistent organochlorine pesticides (OCPs) residues in cow milk from Ekiti State University Agricultural farm in Ado-Ekiti, Nigeria. The study was investigated in order to monitor consumer’s exposure to these chemicals pesticides. Methods: Qualitative identification and quantification evaluation of the extracted pesticides after clean-up on silica gel were done with a Gas Chromatography coupled with an Electron Capture Detector (GC-ECD). Results: The results revealed the presence of 11 OCPs residues in the milk samples, with concentration range of 0.001 - 0.189 mg/l, while α-BHC, endrin, endrin aldehyde, endosulfan II, endosulfan sulphate and methoxychlor were not detected. The analysis of variance revealed no significant variation in the levels of all the analysed pesticides except dieldrin. Conclusion: The hazard indices (HIs) were significantly lower than 1 with the range of 0.00063 - 0.107, indicating no potential health risk.

3 citations


Journal ArticleDOI
TL;DR: In this paper, raw and fried plantain chips obtained from the use and re-use of olive, refined palm olein and coconut oils were investigated for the proximate, mineral compositions, computed mineral ratios and the mineral safety index using standard analytical methods.
Abstract: Raw and fried plantain chips obtained from the use and re-use of olive, refined palm olein and coconut oils were investigated for the proximate, mineral compositions, computed mineral ratios and the mineral safety index using standard analytical methods. For the selected oils (both use and re-use): first and second re-use and the fresh plantain chips (unprocessed plantain chips; UPC) had the following range results: proximate composition (%) (moisture: 8.20 - 12.3, crude protein: 9.70 - 8.60, fat: 7.40 - 12.9, fibre: 3.50 - 4.90, ash: 2.80 - 3.80 and carbohydrates: 63.5 - 64.8), % energy contributions (PEC: 63.4 - 70.8, PEF: 20.2 - 28.6, PEP: 8.03 - 9.66, UEDP: 4.49 - 5.08). The mineral composition (mg/100g) of the samples had the following greater than 80.0: Ca, Mg, K and P; Fe, Cu, Mn and Zn recorded values ranging between 1.00 and 4.00; Co, Se and Ni had their concentrations between 0.00 and 0.0363 whereas Pb and Cd recorded levels lower than 0.0006. In the mineral ratios, only K/(Ca + Mg) values fell within the acceptable ideal range. No MSI aberration was observed for the minerals from all the samples obtained from the various oils. The chi-square analysis showed that on parameter wise comparisons, there were no significant differences among the levels as treated based on the various oils except gross energy, Mg, K, P, Ca/P, Fe/Pb and K/Co. Also on pairwise comparison from linear correlation and regression, all these parameters were significantly different at r = 0.01 between the unprocessed and fried plantain samples: proximate, percentage energy distribution, mineral and mineral ratios. Generally, the first (day) frying showed fairly high nutrient concentration than the first and second re-use oils products. Therefore, for optimum nutrient preservation from fried plantain chips re-use of oil for frying should be sparingly allowed. However, olive showed highest level of nutrients in terms of proximate and mineral compositions.

3 citations


Journal ArticleDOI
TL;DR: In this article, the physicochemical and organoleptic properties of virgin olive oil in the region of Tlemcen have been compared with traditional extraction and industrial extraction, and they concluded on the advantages and disadvantages of each of the two processes.
Abstract: Virgin olive oil is obtained from the fruit of the olive tree, and only using physical processes, without resorting to refining steps, the absence of the latter allows the olive oil to retain all its antioxidants. This work is a contribution to the characterization of the properties of olive oil in the region of Tlemcen. They relate more particularly to the comparison of the physicochemical properties of two oils, one from traditional extraction and the other from industrial extraction. To do this, the first objective of studies of the two chains of transformation (traditional and industrial) was made followed by a physicochemical and organoleptic comparison of these two oils of olives, to conclude on the advantages and disadvantages of each of the two processes.

Journal ArticleDOI
TL;DR: In this paper, a study was conducted in cultivated and uncultivated saline soil, in order to assay soil organic carbon, its particle-size fractions and their influence on cultivation and soil fertility at Sundarbans costal area in Bangladesh.
Abstract: Assessment of soil organic matter fractions can be instrumental in understanding the causes of limited nitrogen supply, and thus soil fertility restoration. A study was conducted in cultivated and uncultivated saline soil, in order to assay soil organic carbon (SOC), its particle-size fractions and their influence on cultivation and soil fertility at Sundarbans costal area in Bangladesh. Soil samples were taken from the 0 - 15 and 15 - 30 cm depths from four cultivated fields and from four nearby sites in a native mangrove forest as references. Soil samples were physically fractionated into sand (2000-50 μm), silt (50-2 μm) and clay ( silt > sand. The SOC pool and N in the clay-sized fraction were correlated to soil fertility indicators. More N was stored in the silt + clay size fractions, a generally more stable pool, than in the more labile sand-sized pool. The SOC pool in sand size fractions was far below in cultivated soils than in a reference uncultivated soil. Thus, the sand-sized pool emerged as the most likely cause of limited N supply in cultivated soils.

Journal ArticleDOI
TL;DR: In this article, chemical structures of some frequently used commercial fertilizers (compost, DAP, and TSP) and their phosphate-metal interaction chemistry were studied employing both analytical and theoretical methods.
Abstract: Fertilizers are the indispensable materials for farming and one of the major components of the current world economy. It is essential to understand the chemical structures of fertilizers to provide best quality products to the consumers. In this study, chemical structures of some frequently used commercial fertilizers (compost, DAP, and TSP) and their phosphate-metal interaction chemistry were studied employing both analytical and theoretical methods. Three types of fertilizer samples from the mid-southern part of Bangladesh were collected to quantify the content of two micronutrient metals (iron and zinc) and two non-essential metals (scandium and samarium). Neutron activation analysis (NAA) coupled with γ-ray spectrometry was employed to analyze the content of the metals where three standard reference materials, namely IAEA-SL-1 (Lake Sediment), IAEA-Soil-7, and NIST Coal Fly Ash 1633b, were used. Concentration of Fe (2964 - 24,485) mg/kg, Sc (3.50 - 11.80) mg/kg, Sm (2.19 - 26.69) mg/kg, and Zn (243 - 4426) mg/kg were determined in the fertilizer samples. Extremely high concentrations of Fe and Zn were quantified in some of the compost and phosphate fertilizers in comparison with other studies of different countries. Quantum mechanical calculations were performed to understand the molecular level interactions of Fe and Zn with triple super phosphate (TSP) and diammonium phosphate (DAP) fertilizers by employing DFT-B3LYP/SDD level theory. Results showed that both Fe and Zn have high affinity with the phosphate fertilizers, but Fe compound showed stronger binding affinity than the Zn compounds, which supported the experimental results. Another interesting finding was that the compounds of Fe and Zn attached to the oxygen of the phosphate group of the fertilizers by covalent-like bonding. HOMO-LUMO gaps of the Fe-DAP/TSP complexes were observed significantly lower than the Zn-DAP/TSP, which also demonstrated that Fe compound could have higher affinity to attach with the phosphate group of DAP and TSP fertilizers.

Journal ArticleDOI
TL;DR: Chitosan/coconut composite membranes were successfully prepared by the cross-linking reaction with glutaraldehyde and they were applied in eliminating heavy metals from aqueous solutions as discussed by the authors.
Abstract: Chitosan/coconut (CTS/coconut) composite membranes were successfully prepared by the cross-linking reaction with glutaraldehyde and they were applied in eliminating heavy metals from aqueous solutions. The cross-linked membranes were obtained at the ratios of 1/1, 1/1.5 and 1/2 and the coconut fiber was chemically treated by NaOCl/NaOH. The best ratio of CTS/coconut fiber is found to be 1/1.5 which has a relatively high stability with the degree of swelling (DS) and solvent content (SC) of membrane to be 13.33% and 69.88%, respectively. The results also indicate that the CTS membranes showed preferential separation of heavy metals for blend CTS/coconut membranes.

Journal ArticleDOI
TL;DR: In this paper, the authors proposed an optimized process for farm product convective drying, and showed that product internal parameters and drying proceedings must be taken into account during the evaluation of their convective driings.
Abstract: In this paper, we propose an optimized process for farm product convective drying. Above and beyond the influence of the air parameters on foodstuff convective drying, this work shows that product internal parameters and drying proceedings must be taken into account during the evaluation of their convective drying. Results indicate that okra maturity influences its convective drying. It dries faster when it is too young or when it is advanced age. Drying time of okra of 1, 2, 3, 4 and 5 days old is respectively 580 min, 780 min, 990 min, 1200 min and 850 min. Also, one observes that considering okra on its three zones according it length, i.e. its base, middle and extremity parts have not the same resistance to transfers during convective drying. These three zones have respectively 400 min, 520 min and 600 min of drying time. Okra cut reveals a major importance on its convective drying evaluation. The longitudinal cut di-viding okra on four parts, sliced with 5 mm and 10 mm of thickness and the whole okra put respectively 150 min, 200 min, 280 min and 400 min for their drying. At last, three (03) different constituents of okra, namely, the skin, the seeds and central material behave differently during convective drying. The drying time of the central material, the seeds and the skin is about 70 min, 150 min and 190 min respectively, against 400 min for the whole okra.

Journal ArticleDOI
TL;DR: In this article, the authors investigated the co-digestion of corn stalks with cow dung and poultry droppings in anaerobic conditions, and concluded that co digestion of chicken droppings is beneficial for improving biodigestibility and Biogas yield from corn stalk.
Abstract: The Anaerobic digestion of Corn Stalk (CS) with Cow Dung (CD) and Poultry Droppings (PD) was investigated. Batch mono-digestion and Co-digestion experiments were performed with initial total solid loading of 37.5%. The main objective of this work was to investigate the biogas yield at different CS to CD ratios and CS to PD ratios. Results show that the highest Cumulative Gas Yield (CGY) of 6833 mL/g of biomass was achieved in 21 days for CS-CD ratio of 2:1. Similarly high CGY of 6107 mL/g, 6100 mL/g and 5333 mL/g were obtained for CS-PD ratio of 2:1, CS-CD ratio of 1:1 and CS-PD ratio of 1:1 respectively. It is concluded that co-digestion of Cow dung or poultry droppings is beneficial for improving bio-digestibility and Biogas yield from corn stalk. The results of this work provide useful information to improve the efficiency of co-digestion of CS with CD and PD under anaerobic conditions.