Optimal Size for Maximal Energy Efficiency in Information Processing of Biological Systems Due to Bistability

Energy efficiency is closely related to the evolution of biological systems and is important to their information processing. In this work, we calculate the excitation probability of a simple model of a bistable biological unit in response to pulsatile inputs, and its spontaneous excitation rate due to noise perturbation. Then we analytically calculate the mutual information, energy cost, and energy efficiency of an array of these bistable units. We find that the optimal number of units could maximize this array＇s energy efficiency in encoding pulse inputs, which depends on the fixed energy cost. We conclude that demand for energy efficiency in biological systems may strongly influence the size of these systems under the pressure of natural selection.

Cultivation of different strains of Lentinus tigrinus from selected areas of Luzon Island,Philippines

Lentinus tigrinus is a wood-decaying species of macrofungi that belongs to family Polyporaceae.This mushroom is known to be edible and with medicinal attributes.In this study,cultivation of different strains of Lentinus tigrinus using rice straw-sawdust based substrate is reported.Results showed that the shortest incubation period was observed in strain 10(16.60 days),and the longest was noted in strain 1(40.50 days).However,strain 10 showed the earliest appearance of fruiting initials(20.70 days),and strain 1 had the longest period(44 days).In terms of fruiting body size,strain 6 recorded the widest mean pileus diameter(72.2 mm),and strain 10 had the longest mean stipe length(41.22 mm).Moreover,strain 6 produced the highest yield of 81.83 g and biological efficiency of 16.37%.Interestingly,although they belong to the same species,cultivation phase and fruiting body performance of different strains of L.tigrinus may also vary depending on geographical origin,which is very important to consider in strain selection.

Advances in Biological Water-saving Research:Challenge and Perspectives

Increasing the efficiency of water use by crops continues to escalate as a topic of concem because drought is a restrictive environmental factor for crop productivity woridwide .Greater yield per unit rainfall is one of the most important challenges in water-saving agriculture Besides water-saving by irrigation engineering and conservation tillage, a good understanding of factors limiting and/or regulating yleld now provides us with an opportunity to identify and then precisely seiect for physiciogical and breeding traits that increase the efficiency of water use and drought tolerance under water-limited conditions, biological water-saving is one means of achieving this goal, A definition of bilogical water-saving measures is proposed which embraces improvements in water use efficiency （WUE） and drought tolerance, by genetic improvement and physiological regulation. The preponderance of bilogical water-saving measures is discussed and strategies identified for working within natural resource constraints. The technology and future perspectives of bilogical water saving could provide not only new water-saving techniques but also a scientific base for application of water-saving irrigation and conservation tillage.

Cultivating Pleurotus ostreatus and Pleurotus eryngii mushroom strains onagro-industrial residues in solid-state fermentation. Part II: Effect onproductivity and quality of carposomes

The potential of selected Pleurotus ostreatus and P. eryngii wild-type and commercial strains to colonize andproduce carposomes after solid-state fermentation of five substrates constituted of agro-residues namely wheatstraw (WS), beech wood shavings (BWS), coffee residue (CR), barley and oats straw (BOS), rice bark (RB),supplemented with wheat bran was investigated. The effect of substrate composition on bioprocess feasibilitywas assessed for the different strains by quantitative (i.e., mushroom yield and Biological Efficiency-BE %) andcarposome qualitative parameters (i.e., weight, size, colour, firmness). P. ostreatus strains produced carposomesearlier than P. eryngii ones. Early fruiting formation was promoted in WS for P. ostreatus strains, whereas forP. eryngii the lowest values of earliness were observed on BOS substrate. As for crop productivity, P. ostreatusstrain AMRL 150 provided the highest BE (>70%) in all substrates except for RB, while P. ostreatus strain AMRL144 achieved the highest yield and BE in BOS and BWS (75.30 and 64.26%, respectively). P. eryngii stainsproduced less number but heavier carposomes. The highest values of BE% for these strains were recorded on WSand BOS substrates. The BE was further correlated to growth parameters of fungal vegetative phase. As formushroom colour, P. ostreatus were lighter than P. eryngii and BOS substrate promoted lightness in both strains.Firmer P. ostreatus mushrooms were produced at CR. No differences in the whiteness and firmness were detectedamong P. eryngii mushrooms and at any substrate used. The data included in this paper showed that Pleurotusmushrooms can be cultivated on low- or zero-value agro-industrial residues of great financial and environmentalimportance towards the production of value-added food products.

Evaluation of ligninolytic activity in spent mushroom substrate from four cultivated mushrooms

Spent mushroom substrate(SMS)is an abundant residue generated by the mushroom industry,which is mostly discarded.In this study,the SMS of four cultivated mushrooms were evaluated as potential sources of ligninolytic enzymes.Pleurotus ostreatus,P.eryngii,P.djamor and Ganoderma lucidum were cultivated in two different substrates to determine growth,mushroom yields and ligninolytic activity of laccase(Lac)and manganese peroxidase(MnP).Maximum activities in the SMS were 3.731 U/g Lac and 0.191 U/g MnP,both for P.eryngii.Colonized mushroom substrates were also analyzed,and higher activities were found in almost all samples.A correlation test between mushroom yields and ligninolytic activities of each culture was made,and we found that high enzymatic activity in the substrate did not result in high mushroom productivity or vice versa.The SMS was a good source of ligninolytic enzymes.Enzymatic activity depended on the mushroom species and its affinity to the substrate,and it was not influenced by the mushroom yields.Production of mushrooms in diverse lignocellulosic substrates is gaining interest,and ob-taining ligninolytic enzymes from residual SMS is an excellent alternative in the circular economy concept.

Utilization of spent substrates and waste products of mushroom cultivation to produce new crops of Pleurotus ostreatus,Pleurotus eryngii and Agaricus bisporus

Five agro-industrial residues,their corresponding spent mushroom substrates(SMS),commercial fresh and spent mushroom compost of Agaricus(SMC)and Pleurotus ostreatus(SMS GZ)cultivation,Pleurotus and Agaricus waste(stipes/mishappen mushrooms)were combined and re-utilized as novel substrates for the cultivation of P.ostreatus,P.eryngii and A.bisporus mushrooms.SMSs/SMC were used up to 40%(treatment 1 and 2),while 20%of mushroom waste were added in fresh and spent substrates(treatment 3 and 4).The impact of different substrates on mycelial growth rate and biomass production was examined.Then,Pleurotus spp.were cultivated on the most promising substrates and essential cultivation aspects(earliness,total mushroom yield,biological efficiency-BE)and carposomes’quality parameters(weight,morphological characteristics)were evaluated.Laccase and endoglucanase production by Pleurotus species were also determined at 50 and 100%of colonization stages.All species showed their fastest mycelial growth rate(up to 5 mm/day)on substrates consisted of SMC,whereas many combinations of species/substrate enhanced biomass production.The SMS GZ supplementation positively affected laccase activity;in the cultures of P.ostreatus and P.eryngii the highest values were 62,539 and 17,584 U/g d.w.,respectively.On the contrary,small amounts of endoglucanase were produced(0.007 to 0.322 U/g d.w.);the greatest production was recorded for P.ostreatus at full colonization.Regarding fermentation in bags,significant amount of total mushroom yield was produced in all substrates and those with SMS GZ supported the fastest earliness period and the highest BE for both Pleurotus species.BE values ranged from 54 to 133%for P.ostreatus and from 53 to 121%for P.eryngii.Concerning morphological characteristics,mushroom waste addition seemed to affect them positively.The data included in this paper support the effective re-utilization of different types of SMS and mushroom waste for fungal mass and enzymes’production and for new high quality Pleurotus spp.carposomes.