Influencing factors on single-cell protein production by submerged fermentation: a review

Since more than twenty years ago, some species of bacteria and fungi have been used to produce protein biomass or single-cell protein (SCP), with inexpensive feedstock and wastes being used as their sources of carbon and energy. The role of SCP as a safe food and feed is being highlighted more because of the worldwide protein scarcity. Even though SCP has been successfully commercialized in the UK for decades, study of optimal fermentation conditions, various potential substrates, and a broad range of microorganisms is still being pursued by many researchers. In this article, commonly used methods for the production of SCP and different fermentation systems are briefly reviewed, with submerged fermentation being highlighted as a more commonly used method. Emphasis is given to the effect of influencing factors on the biomass yield and productivity in an effort to provide a comprehensive review for researchers in related fields of interest.

A novel cost-effective medium for in vitro cultivation of Gentiana kurroo Royle using sugarcane bagasse

Objective: To develop a simple, cost-effective, and efficient medium by using sugarcane bagasse (SB) as abase material to replace the conventional Murashige and Skoog (MS) medium.Materials and Methods: Water extracts of SB along with some macronutrients and plant growth regulators weregelled with 0.7% agar-agar powder. Nodal segments of Gentiana kurroo were used as explants and inoculatedin the medium and placed in a growth chamber under standard conditions of light and temperature. Out of thetested combinations of plant growth regulators, 0.5 mg/l each of kinetin (KN) and 6-Benzylaminopurine (BAP)showed the excellent shoot multiplication and proliferation rate on the bagasse medium with the same potentialas on the MS medium with an average of 5–6 shoots/explant. In vitro rooting was obtained on half strength MSmedium supplemented with IBA (0.5 mg/l) with an average length of 7–8 cm and 20–25 roots/explant. Theplants were hardened in a mixture of clay loam and farmyard manure in 1:1(w/w) with 70%–80% survival ratewithout any phenotypic aberrations.Conclusion: The results from the present investigation indicate that SB can be used as a cost-effective substituteof MS medium for in vitro propagation of G. kurroo.

Green synthesis of gold nanoparticles from waste macadamia nut shells and their antimicrobial activity against Escherichia coli and Staphylococcus epidermis

Background: The study for the first time demonstrates an eco-friendly and room temperature procedure for biosynthesizing gold (Au) nanoparticles from waste Macadamia nut shells. Currently Australia contributes around 40% to the global market and generates around AUS $150 million of export revenue. However, a consequence of large nut production is the generation of large quantities of waste nut shells. The green chemistry-based method is clean, nontoxic and eco-friendly. The method presented in this study produced a variety of Au nanoparticle sizes and shapes.Methods: The straightforward green chemistry-based technique used waste Macadamia nut shells to generate Au nanoparticles, which were subsequently studied using several advanced characterization techniques. Furthermore, the Kirby-Bauer sensitivity method was used to evaluate the antibacterial properties of the extracts and synthesized gold nanoparticles.Results: Advanced characterisation revealed the Au nanoparticles were crystalline, ranged in size from 50nm up to 2µm, and had spherical, triangular and hexagonal morphology. The gram-negative bacteria Escherichia coli produced a maximum inhibition zone of 11mm, while Staphylococcus epidermidis produced a maximum inhibition zone of 9mm.Conclusions: The study has shown that waste Macadamia nut shell extracts have no antibacterial activity, but the synthesised Au nanoparticles did display antibacterial activity to both Escherichia coli and Staphylococcus epidermidis. Thus, the present work has demonstrated a waste valorisation strategy that can be used to produce high-value Au nanoparticles with antimicrobial properties for use in future pharmaceuticals.

GIS-Based Estimate of GHG Emission from Livestock in Anambra State of Nigeria

The need for improved livestock waste management in developing countries has been emphasized by various researchers. Consideration has been given globally to advocacy for a transition from fossil energy system to Renewable Energy (RE), based on several socio-economic and environmental advantages. Green House Gas (GHG) from agricultural sector of Anambra State, with appropriate waste management strategy such as Anaerobic Digestion (AD) will definitely mitigate Methane emission hazards and will as well supply the much needed energy for domestic and industrial uses. An investigation was carried out in this study to estimate the Methane Emission Potential (MEP) of the study area as a result of poor livestock waste management system practiced in the area. This was achieved by incorporating Geographical Information System (GIS) capability to the Methane estimation. The result of the study shows that two Local Government Areas (LGA) which are Anambra West and Anambra East were the least in MEP with virtually none and 0.000646 Gg/year respectively. Idemili North LGA with MEP of 0.017962 Gg/year was observed to be the highest in Methane emission. On incorporating spatial density mapping on MEP, Onitsha North and Idemili North LGA were identified as the highest risk LGAs, with MEP of 0.00018 Gg/year and 0.000272 Gg/year respectively. The study suggests that an improved livestock waste management system using AD should be incorporated in the study area especially in the high risk zones of Onitsha and Idemili North LGA.

Eucalyptus wood and coffee parchment for particleboard production: Physical and mechanical properties / Madeira de eucalipto e pergaminho de café na produção de aglomerados: Propriedades físicas e mecânicas

ABSTRACT The wood panel industry is constantly growing, being necessary the innovation in technologies and raw materials to improve the quality of the final product. Considering the shortage and pressure to decrease the dependence of wood, there is an interest in other renewable materials such as agricultural wastes. Among these wastes, coffee parchment is one which deserves notoriety. An alternative use for coffee parchment could be for production of particleboard in association with wood particles. This study aimed to evaluate the feasibility of using coffee parchment for production of particleboard. The following percentages of wastes were used: 0, 10, 20, 30, 40 and 50% in association to eucalyptus wood. The panels were produced with 8% of urea formaldehyde (based on dry weight of particles). The pressing cycle consisted by: pre-pressing of 0.5 MPa for 10 minutes followed by pressing of 4.0 MPa, and temperature of 160° C for 15 minutes. The compaction ratio of particleboards produced using higher quantities of parchment improved the physical properties. The properties of Water Absorption (2 and 24 h) and Thickness Swelling (2 h) decreased with increasing percentage of coffee parchment. The Thickness Swelling (24 h) showed not significant effect with an increase of coffee waste. The Modulus of Elasticity for coffee parchment particleboards was in the range 646.49 ± 112.65 to 402.03 ± 66.24 MPa, while the Modulus of Rupture ranged from 8.18 ± 1.39 to 4.45 ± 0.75 MPa. The results showed that 10% of coffee parchment could be added for production of particleboards.

RESUMO A indústria de painéis de madeira vem em constante crescimento, sendo necessária a inovação em tecnologias e matéria-prima para melhorar a qualidade do produto final. Considerando a escassez e pressão na diminuição da dependência por madeira, existe um interesse em outros materiais renováveis, como os resíduos agrícolas. Entre esses resíduos, o pergaminho de café merece destaque. Uma alternativa para utilização do pergaminho de café poderia ser na produção de particulados, em associação com partículas de madeira. O objetivo deste trabalho foi avaliar a viabilidade de utilização do pergaminho de café para produção de aglomerados. As porcentagens de resíduo utilizadas foram: 0, 10, 20, 30, 40 e 50% em associação com madeira de eucalipto. Os painéis foram produzidos com 8% de uréia-formaldeído (base massa seca de partículas). O ciclo de prensagem consistiu de: pré-prensagem de 0,5 MPa por 10 minutos, seguido por prensagem de 4,0 MPa e temperatura de 160° C por 15 minutos. A razão de compactação dos painéis produzidos com maiores quantidades de pergaminho melhorou as propriedades físicas. As propriedades de absorção de água (2 e 24 h) e inchamento em espessura (2 h) diminuíram com o aumento da porcentagem de pergaminho de café. O inchamento em espessura (24 h) não apresentou diferenças significativas com o aumento de resíduo de café. O Módulo de Elasticidade dos painéis variou de 646,49 ± 112,65 até 402,03 ± 66,24 MPa, enquanto o Módulo de Ruptura variou de 8,18 ± 1,39 até 4,45 ± 0,75 MPa. Os resultados mostraram que até 10% de pergaminho de café poderia ser adicionados para a produção de painéis aglomerados.

Maintenance culture medium and inoculum based on peach palm leaves for Pleurotus spp. production / Meio de manutenção e inóculo a partir de folhas de pupunheira para a produção de Pleurotus spp

This study evaluated the use of immersion water from peach palm leaves (PPLDA) as a component of the culture medium for the maintenance of Pleurotus spp. and the use of agricultural waste, peach palm leaves, as inoculum support for the fungi. The performance of the inoculum based on peach palm leaves (PPL) for the production of Pleurotus spp. fruiting bodies was compared with that using wheat grains (WG) as inoculum support. PPLDA culture medium (immersion water of peach palm leaves, dextrose, and agar) showed a lower radial velocity of mycelial growth for both fungi than that obtained with the culture medium WDA (wheat extract, dextrose and agar), commonly used as maintenance medium for Pleurotus spp. However, the type of inoculum support does not significantly influence the linear velocity of P. ostreatus mycelial growth, reaching 6.71 mm/day on wheat grains and 6.18 mm/day on peach palm leaves. Thus, when the inoculum based on peach palm leaves is utilized, the immersion water used for preparing this support can be used for preparing the PPLDA maintenance culture medium, diminishing the production costs of Pleurotus mushrooms. Data also showed that when Pleurotus sajor-caju was cultivated on peach palm leaves, using PPL as inoculum support, the fruiting bodies production parameters (Y = 47%, BE = 3% and Pr = 0.2 g/day) did not differ from that obtained using WG.(AU)

Este trabalho avaliou a utilização da água de imersão das folhas de pupunheira como componente do meio de cultivo para manutenção da cepa fúngica e a produção de inóculo de Pleurotus spp. utilizando como suporte folhas de pupunheira, um resíduo agrícola. Ainda, para verificar a capacidade do inóculo à base de folhas de pupunheira (FP) de produzir corpos frutíferos, foi realizado um experimento comparando FP com o inóculo à base de grãos de trigo (GT). Para tanto, realizou-se a comparação das velocidades de crescimento radial entre o meio de cultivo TDA (extrato de trigo, dextrose e ágar) utilizado para a manutenção de fungos do gênero Pleurotus e o meio FPDA (água de imersão de folhas de pupunheira, dextrose e ágar), e a comparação das velocidades de crescimento linear entre os grãos de trigo, utilizados como suporte para o inóculo de fungos do gênero Pleurotus e as folhas de pupunheira. O meio de cultivo TDA apresentou velocidade radial superior ao meio FPDA para as duas espécies, no entanto, o tipo de suporte não influenciou significativamente a velocidade de crescimento linear de P. ostreatus , que apresentou 6,71 mm/dia em grãos de trigo e 6,18 mm/dia em folhas de pupunheira. Assim, quando o inóculo à base de folhas de pupunheira é utilizado, a água de imersão deste suporte pode ser aproveitada para a confecção do meio de cultivo de manutenção (FPDA), diminuindo os custos produção. Observou-se que Pleurotus sajor-caju , quando cultivado em folhas de pupunheira utilizando inóculo FP, apresentou cerca de 47% de rendimento, 3% de eficiência biológica e 0,2 g/dia de produtividade, sem diferença significativa com o inóculo GT.(AU)

Enhanced production of prodigiosin by Serratia marcescens MO-1 using ram horn peptone

This work addresses the production of prodigiosin from ram horn peptone (RHP) using MO-1, a local isolate in submerged culture. First, a novel gram-negative and rod-shaped bacterial strain, MO-1, was isolated from the body of the grasshopper (Poecilemon tauricola Ramme 1951), which was collected from pesticide-contaminated fields. Sequence analysis of 16S rDNA classified the microbe as Serratia marcescens. The substrate utilization potential (BIOLOG) and fatty acid methyl ester profile (FAME) of S. marcescens were also determined. The effect of RHP on the production of prodigiosin by S. marcescens MO-1 was investigated, and the results showed that RHP supplementation promoted the growth of MO-1 and increased the production of prodigiosin. A concentration of 0.4% (w/v) RHP resulted in the greatest yield of prodigiosin (277.74 mg/L) after 48 h when mannitol was used as the sole source of carbon. The pigment yield was also influenced by the types of carbon sources and peptones. As a result, RHP was demonstrated to be a suitable substrate for prodigiosin production. These results revealed that prodigiosin could be produced efficiently by S. marcescens using RHP.

Identification of Suitable Condition for Mannanase Production by Bacillus sp. GA2(1).

Aims: The effects of 1% (w/v) supplementation of additional 5 agricultural wastes, corn cob, bagasses, coffee residues, soybean meal, and copra meal for mannanase production by Bacillus sp.GA2(1) were studied. Hence, partial characterization of mannanase was determined. Methodology: The 1%(v/v) overnight cultured of Bacillus sp. GA2(1) was transferred into the basal medium and shaken at 150 rpm for 18 h at 37ºC. The additional of 5 AWs, corn cob, bagasses, coffee residues, soybean meal, and copra meal for the mannanase production were investigated. The cell suspension was centrifuged, and the crude mannanases were collected and stored at – 20ºC for enzyme assay. The mannanase activities were measured by the dinitrosalicylic acid method. The optimal pH of mannanase were studied by measuring enzyme activity at pH 3-10 using 50 mM of following buffers; citrate (pH 3.0-6.0), phosphate (pH 6.0-8.0), and glycine-NaOH (pH 8.0-10.0). The optimal temperature was measured at 30-80ºC. Under standard assay conditions, locust bean gum was used as substrate to determine the optimal pH and temperature of the reaction. Thermostability was determined by preincubating the enzyme at different temperatures (30-80ºC) for 1 h. The residual mannanase activities were measured under standard condition. Results: Among bagasses, coffee residues, soybean meal, corn cob and copra meal, the coffee residues was the most effective carbon source, the maximum yield of mannanase activity was 0.26 U/ml. The optimal temperature and pH for mannanase activity was pH 6.0 and 50ºC of 0.44 and 0.35 U/ml, respectively. The stability of enzyme was determined at 30-80ºC for 60 min. The results revealed that mannanase retained more than 96% of remaining activity after incubation of 60 min at 50ºC. Conclusion: The maximum mannanase production was found when the medium was supplemented with coffee residues. Crude mannanase showed the highest activities of 0.44 U/ml at pH 6.0 and of 0.35 U/ml at 50ºC. The mannanase from Bacillus sp. GA2(1) retained more than 90% of theirs activities at 30-60ºC after preincubated for 60 min and then rapidly decreased.

The hydrolysis of agro-industrial residues by holocellulose-degrading enzymes

Holocellulose structures from agro-industrial residues rely on main and side chain attacking enzymes with different specificities for complete hydrolysis. Combinations of crude enzymatic extracts from different fungal species, including Aspergillus terreus, Aspergillus oryzae, Aspergillus niger and Trichoderma longibrachiatum, were applied to sugar cane bagasse, banana stem and dirty cotton residue to investigate the hydrolysis of holocellulose structures. A. terreus and A. oryzae were the best producers of FPase and xylanase activities. A combination of A. terreus and A. oryzae extracts in a 50% proportion provided optimal hydrolysis of dirty cotton residue and banana stem. For the hydrolysis of sugar cane bagasse, the best results were obtained with samples only containing A. terreus crude extract.

Influência da composição química do substrato no cultivo de Pleurotus florida / Influence of the chemical composition of the substrate in the cultivation of Pleurotus florida

Com o objetivo de avaliar a influência da composição química do substrato no cultivo do cogumelo comestível Pleurotus florida, seis resíduos agrícolas foram testados: palha de arroz, palha de feijão, palha de trigo, folha de bananeira, palha de sorgo e sabugo de milho. O substrato palha de feijão apresentou resultados semelhantes para a produção (189,8 g kg-1), eficiência biológica (89,2 por cento) e número de cogumelos (12) à palha de arroz, substrato utilizado tradicionalmente no cultivo de Pleurotus em escala comercial. Não foi possível atribuir apenas a um fator químico as altas produções e eficiências biológicas observadas em palha de arroz e palha de feijão e muito menos para a baixa produção em palha de sorgo (77,8 g kg-1) e sabugo de milho (53,2 g g-1). No geral, substratos com relação C/N em torno de 45 (N = 1,0 por cento), maior conteúdo de cinzas, acrescido de altos teores de P, K, Ca, Mg and Mn foram os melhores para o cultivo de P. florida.

The purpose of this work was to evaluate the influence of the chemical composition of the substrate in the cultivation of the edible mushroom Pleurotus florida. Six agricultural by-products were tested: rice straw, bean straw, wheat straw, banana leaf, sorghum straw and maize cobs. Using bean straw as the substrate showed similar results for yield (189.8 g kg-1), biological efficiency (89.2 percent) and number of mushrooms (12) as rice straw substrates traditionally used for the cultivation of Pleurotus on a commercial scale. It was not possible to attribute the high yields and biological efficiency observed in rice and bean straw solely to chemical factors and, even less so for the low yields presented by sorghum straw (77.8 g kg-1) and maize cobs (53.2 g kg-1). In general, substrates with C/N ratio around 45 (N = 1.0 percent), high ash content and high levels of P, K, Ca, Mg and Mn were the best for the cultivation of P. florida.

Study on the removal of cresol for the agricultural waste water treatment / 日本農村医学会雑誌

Concerning the agricultural waste water treatment, adsorption removal of cresol which is one of disinfectants by commercial activated carbon was investigated.<BR>It was not found the significant correlation between amount of cresol adsorbed and physical properties of eight kinds of activated carbon. The intraparticle diffusivity of cresol onto the pores of activated carbon was significantly related to the mesopore volume.<BR>In the treatment of agricultural waste water, it is concluded that the activated carbon which is rich in mesopore volume is suitable for the adsorption removal of cresol from the standpoint of adsorption rate.

Study on the phenol removal for the security of water quality in rural areas / 日本農村医学会雑誌

For the security of water quality in rural areas, adsorption removal of phenol which is one of disinfectants for excretions by six kinds of commercial activated carbon was investigated.<BR>At equilibrium concentration of 1 and 10 ppm, activated carbon indicated pH 10.19 adsorbed phenol as much as 2.17 and 1.84 times compared with activated carbon indicated pH 3.06, respectively. At low equilibrium concentration of phenol, the amount adsorbed was significantly influenced by surface pH of activated carbon (p <0.05).<BR>These results suggest that the difference in amount of phenol adsorbed onto activated carbon is due to the interaction between phenol and surface oxygen groups on the adsorbent. Therefore, it is concluded that the activated carbon of which surface is basic suitable for the adsorption removal of phenol in the agricultural waste waters.