Digital library

  • A UK Roadmap for Algal Technologies

    Algae have attracted considerable interest globally as a potential feedstock for a biobased economy. The industrial and research communities in the UK have much to offer in this space: UK companies and academics have laid the foundations for several now globally-used algal biotechnology and engineering advances, and as an island nation we have a strong history in macroalgal commercial activities.

    This roadmap has been commissioned by the NERC-TSB Algal Bioenergy Special Interest Group, to complement its Strategic Research Agenda of 2012. It focuses on the commercialisation potential of algaerelated products, processes and services for the UK, being mindful of environmental implications. It builds on the outcomes of two workshops held by AB-SIG in October and November 2012 with a variety of stakeholders, whose contributions are gratefully acknowledged.

    The report signposts the strengths of the UK science base, gives a snapshot of UK and global algal industries, and presents an overview of trends and opportunities for algae–derived products and services. Based on these, it assesses the UK’s potential for profiting from international markets, and highlights actions required to compete in a global marketplace. It then presents seven sectors which the workshop participants had identified as being of particular relevance and value for the UK. Examples of products or processes in each sector are given in case studies which evaluate their commercial, technical and environmental strengths and weaknesses. 

    Author(s): B. Schlarb-Ridley , B. Parker

  • Ability of sandfish (Holothuria scabra) to utilise organic matter in black tiger shrimp ponds

    Due to frequent viral disease outbreaks, a large proportion of shrimp aquaculture in South-East Asian countries has switched from black tiger shrimp (Penaeus monodon) to P. vannamei, an exotic species originally imported from Latin America. One of the causes of disease outbreaks is thought to be poor water and sediment conditions in the shrimp ponds, which may aggravate disease symptoms. To obtain basic information for co-culture methods of black tiger shrimp and sandfish (Holothuria scabra) for possible mitigation of shrimp-pond eutrophication and prevention of disease outbreaks, basic laboratory experiments were conducted at the Southeast Asian Fisheries Development Center—Aquaculture Department in Iloilo, the Philippines. A feeding trial of juvenile sandfish showed that they do not grow well with fresh shrimp feed on hard substrate. Another trial indicated that sand substrate enhances the growth of juvenile sandfish fed with shrimp feed. A feeding trial using shrimp tank detritus, shrimp faeces and Navicula ramosissima (a benthic diatom) as food sources showed that sandfish grew fastest with the faeces, followed by detritus and N. ramosissima. Dissolved oxygen consumption and acid-volatile sulfur levels in the shrimp tank detritus were reduced by sandfish feeding. This suggests that sandfish are capable of growing with organic matter in shrimp ponds, and can bioremediate shrimp-pond sediment.

    Author(s): Satoshi Watanabe, Masashi Kodama, Jacques M. Zarate, Maria J.H. Lebata-Ramos, Marie F.J. Nievales

  • Acclimation Responses to Salinity of Three Estuarine Red Algae from New Jersey

    The effects of salinity and acclimation time on the net photosynthetic responses of 3 estuarine red algae, Bostrychia radicans Mont., Caloglossa leprieurii (Mont.) J. Ag., and Polysiphonia subtilissima Mont., from Great Bay Estuary, New Jersey, USA, were investigated. The algae were cultured in a series of synthetic seawater media of 5, 15, 25 and 35% S for acclimation periods of 0, 2, 4, 8, and 16 days prior to determining their photosynthetic responses. All species were euryhaline, and demonstrated photosynthesis at all the above salinities. B. radicans, which was more common towards the mouth of the estuary, had a maximum photosynthetic rate at 25% S, whilst C. leprieurii and P. subtilissima, which were more common towards the head of the estuary, had photosynthetic maxima between 15 and 25%, and at 15%, respectively. The curves relating net photosynthesis to salinity were usually similar within a species at different acclimation periods, although statistically significant differences were sometimes noted. The acclimation periods producing maximal net photosynthesis were 0, 2 and 4 days for B. radicans, and 4 days for C. leprieurii, whilst for P. subtilissima there was no significant difference in response for any acclimation period over the range of salinities studied.The effects of salinity and acclimation time on the net photosynthetic responses of 3 estuarine red algae, Bostrychia radicans Mont., Caloglossa leprieurii (Mont.) J. Ag., and Polysiphonia subtilissima Mont., from Great Bay Estuary, New Jersey, USA, were investigated. The algae were cultured in a series of synthetic seawater media of 5, 15, 25 and 35% S for acclimation periods of 0, 2, 4, 8, and 16 days prior to determining their photosynthetic responses. All species were euryhaline, and demonstrated photosynthesis at all the above salinities. B. radicans, which was more common towards the mouth of the estuary, had a maximum photosynthetic rate at 25% S, whilst C. leprieurii and P. subtilissima, which were more common towards the head of the estuary, had photosynthetic maxima between 15 and 25%, and at 15%, respectively. The curves relating net photosynthesis to salinity were usually similar within a species at different acclimation periods, although statistically significant differences were sometimes noted. The acclimation periods producing maximal net photosynthesis were 0, 2 and 4 days for B. radicans, and 4 days for C. leprieurii, whilst for P. subtilissima there was no significant difference in response for any acclimation period over the range of salinities studied.

    Author(s): S. Casey, P. Edwards, C. Yarish

  • Additions to the algal flora of the Gulf of Mannar and Palk Bay from Mandapam area

    As early as 1927, Prof. M. O. P. Iyengar gave a brief account of the flora of Krusadai Island and other collecting grounds in the Gulf of Mannar and Palk Bay areas near Mandapam. Later on, Boergesen (1937a, b ; 1938) reported a large number of the algae occurring around Mandapam in his contributions on south Indian algal flora, but the green algae of this area were not included in this work. Since then, detailed attempts have not been made to study the algal flora of Mandapam, but for a provisional list of algae of Krusadai Island (Chacko et ah, 1955) and a paper on a new species of Halicystis (Iyengar & Ramanathan, 1954). While working on some ecological aspects of marine algae of Mandapam, the author had the opportunity to collect algae in the different seasons of the year, in the vicinity of Mandapam (79°8' E, 9''17' N) and nearby places like Pudumadam and Kilakarai. Among the collections made since 1964 some plants have not been previously recorded from Mandapam area ; a list of these algae is given in this report with brief notes on their distribution.

    Author(s): Rao, M Umamaheswara

  • Adsorption of Methylene blue and Malachite Green in Aqueous Solution using Jack Fruit Leaf Ash as Low Cost Adsorbent

    The adsorption of mixture of two basic dyes methylene blue and malachite green in aqueous solution onto jack fruit leaf ash in a batch system with respect to initial dye concentrations, pH, contact time, shaker speed and adsorbent doses was investigated.. The pseudo-first-order and pseudo-second- order kinetics model were used to describe the kinetic data. The rate constants at different pH values (3-9.1) were evaluated. The experimental data fitted well with the pseudo-second-order kinetic model. Equilibrium isotherms were analyzed by Langmuir, Freundlich and Temkin isotherm models. Maximum adsorption capacity was 20.41mg/g was achieved by Langmuir isotherm model. Error analysis was done to find the best model that described the experimental data well and it was the Langmuir model. The result indicated that jack fruit leaf ash could be fruitfully employed as low cost adsorbent for the removal of mixture of two basic dyes MB and MG from the wastewater.

    Author(s): Siddhartha Datta, Anupam Debsarkar, Soumitra Banerjee

  • Agar factory discharge as fuel and manure

    Agar factory waste was tried as fuel for cooking and manure for cow pea. Seedlings of cow pea (Vigna ungiculata) supplied with agar factory waste powder, showed improved seedling vigour. The total length of the seedlings (85 - 87%), wet weight (194 - 329%), number of leaves (31 - 38 %) and number of root nodules (42 - 92%) increased than those of control. Out of the two treatments of basal application of agar waste powder, one time application at the time of sowing seeds registered maximum vigour over the control as well as the other treatment which received similar quantity in three intervals. As the 'fuel cakes' prepared out of agar factory waste registered high energy content (19 %), high ash content (20 %) and high rate of combustibility (5 min and 20 sec), these ' fuel cakes' can be ideally used as fuel for cooking.

    Author(s): Kunda , Sumanth Kumar, Kaladharan, P

  • Agar production from Gracilaria with improved qualities

    Agar is manufactured from the red algae Gelidium and Gracilaria. It is one of the commercially important marine products. The agar produced from Gelidium and Gelidiella is considered as the first grade agar and fetches high price. The presence of sulphate content in Gracilaria agar affects the quality of the agar and it is usually sold low price. It is used only as food grade agar. The different Indian and foreign technologies for production of Gracilaria agar with improved yield and quality are given in this paper.

    Author(s): Ramalingam , J R , Kaliaperumal, N, Kalimuthu, S

  • Agar, algin and mannitol from some seaweeds of Lakshadweep

    Studies were made on the yield and physical properties of agar from Gelidiella aceiosa, Gracilaria arcuata and G. edulis and algin and mannitol from Padim boergesenii, Chnoospom implexa, Sargassum duplkatum, Turbimria conoides and T, ormta growing in eight islands of Lakshadweep. The yield of agar ranged from 16.9 to 43.1 % and gel strength from 42 to 278 gm/cm* in G. acerosa, G. arcuala and G. edulis. Algin varied from 4.4 to 27.3%and mannitol from 1.4 to 9.5% in the brown algae studied. The agar and algin yielding seaweeds can be exploited from Lakshadweep Islands as an additional resource of raw material to the Indian seaweed industries.

    Author(s): Kaliaperumal, N, Kalimuthu, S, Ramalingam, J R

  • Agri-offshore wind: How seaweed cultivation and offshore wind farms could help feed the world, create new revenue streams for power operators
    A pioneering project in the Netherlands aims to determine whether offshore wind developments could double up as seaweed farms. The end result could be a nice revenue stream to wind farm operations, at relatively low cost, which is likely to be of interest to renewable power companies. 
    Author(s): Jason Deign

  • ALGAE AS NUTRITION, MEDICINE AND COSMETIC: THE FORGOTTEN HISTORY, PRESENT STATUS AND FUTURE TRENDS

    Marine algae have been known and utilized from the ancient era. It is the source of chemical compounds mainly useful as a food for their richness in protein, fatty acids, minerals and vitamins. Physiologically active compounds also have a great potential to play an important role as cosmetic, medicine and as a pharmaceutical aid. In this review, the provided information will play an important role in the medicinal and cosmeceutical production in future.

    Author(s): Maryam Anis, Salman Ahmed, Muhammad Mohtasheemul Hasan

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