Recent Patents on Biotechnology (v.10, #3)

Meet Our Editorial Board Member by Ryuichi Morishita (227-227).

Background: The interaction of man with the ecosystem is a major factor causing environmental pollution and its attendant consequences such as climate change in our world today. Patents relating to nematodes' relevance in soil quality management and their significance as biomarkers in aquatic substrates were reviewed. Nematodes are useful in rapid, easy and inexpensive method for testing the toxicity of substance (e.g. aquatic substrates).
Objective: This review paper sets out to examine and discuss the issue of soil pollution, functions of nematodes in soil and aquatic substrates as well as bio-indicators in soil health management in terrestrial ecology.
Methods: The information used were on the basis of secondary sources from previous research.
Conclusion: It is abundantly clear that the population dynamics of plant parasitic or free-living nematodes have useful potentials as biomonitor for soil health and other forms of environmental contamination through agricultural activities, industrial pollution and oil spillage, and the analysis of nematode community structure could be used as complementary information obtained from conventional soil testing approaches.

Background: Unraveling the comprehensive networks of molecular signaling in various cellular processes and redesign/rewire them as per human wish is the ultimate dream of the biomedical researchers. Recent advances in the experimental and computational biophysics have provided us with enormous amount of protein sequences and a wide variety of structural information. Protein engineering is a fledging field and a creative process to design the target proteins or signaling networks with desirable structure and functions.
Objective: Protein engineering has been a powerful tool in bioengineering for last couple of decades for generating vast numbers of useful enzymes/proteins that possess huge therapeutic and industrial potential. Now it is the high time to review the existing technologies and tune these methods for a desirable purpose as per the demand of biotechnological/biomedical applications.
Results: Numerous engineering approaches have been developed to generate synthetic protein universe with desired specificity and enhanced performance in comparison to their natural counterparts. The current review provides a glimpse of several of the important computational and experimental methods that are being widely used under the categories of rational design, de novo design, directed evolution and combinatorial approach.
Conclusions: This review shed light on the technicalities, advantages and pitfalls of the existing methodologies along with their applications, recent patents obtained using the engineered proteins and the current and future perspectives of protein engineering techniques.

Heavy Metal Concentration in Periwinkle - Tympanotomus fuscatus in Iko River Estuary, Nigeria by Nsikak O. Abiaobo, Sifon Udi, Ofonmbuk I. Obot (264-271).
Background: Heavy metals are intrinsic, natural constituents of our environment and are generally present in small amounts in natural aquatic environments. Humans may be contaminated by organic and inorganic pollutants associated with aquatic systems by consumption of contaminated aquatic foods from the environment. Relevant patents relating to heavy metal concentration in aquatic molluscs were reviewed. Gastropods; a promising bio-indicator and bio-monitoring subject, abound in brackish ecosystems in the Niger Delta, and are easily available for collection. Iko River Estuary, in Niger Delta zone, is one of the popular coastal areas of Nigeria where massive oil exploitation, exploration, production and refining processes take place.
Methods: The concentration of five heavy metals; Cadmium (Cd), Copper (Cu), Lead (Pb), Mercury (Hg) and Zinc (Zn) in the tissues of periwinkle; Typanotonus fuscatus, a gastropod bought from fishers fishing along the coast of Iko River Estuary was determined using UNICAM Solar Atomic Absorption Spectrophotometer 969 model for five months.
Results: The results showed that Cd ranged from 68.83-130.5mg/kg with a mean value of 104.47±23.85mg/kg, Cu ranged from 34.9-73.62mg/kg with a mean value of 57.70±17.19mg/kg, Pb ranged between 54.27-102.54mg/kg with a mean value of 85.03±18.52mg/kg, Mercury ranged from 0.01-1.84mg/kg with a mean value of 0.41±0.80mg/kg and Zn ranged from 270.2-508.16mg/kg with a mean of 384.99±103.99mg/kg. The sequence of heavy metal concentration in the tissue of periwinkle was; Zn ? Cd ? Pb ? Cu ? Hg while the sequence of non-essential metals was Cd ? Pb ? Hg.
Conclusion: Except for Mercury, the mean concentration of the metals was above the maximum permissible limits recommended by relevant bodies and organizations. Hence, there is need for regular monitoring of heavy metal concentrations in this water body and the aquatic organism inhabitants because of the long term effects.

Background. This study raises awareness to the use of toxic pesticides and reiterates the well-known danger of these pesticides. The acute toxicity of two pesticides, dichlorvos and lindane against the African air-breathing catfish, Heterobranchus longifilis fingerlings was investigated under static bioassay in the laboratory. Relevant patents relating to acute toxicity of pesticides against fish were reviewed. Invention concerning the detection of biomarkers in material from a living organism relates to a method of testing whether a living organism has been exposed to stress, such as pesticide exposure.
Methods. Range finding bioassays were conducted to get the range of concentrations for the definitive bioassays. The range of concentrations of test media for dichlorvos was 0.2 - 1.5 mg l-1 while that of lindane was 35 - 80 mg l-1. The median lethal concentrations were determined using probit analysis.
Results. The test pesticides were found to be differentially toxic to the test species. The 96h LC50 values of 0.8187 and 41.566 mg l-1 for dichlorvos and lindane respectively indicated that dichlorvos was highly toxic while lindane was slightly toxic to the test species. Computed toxicity factor showed that dichlorvos was 50.8 times more toxic than lindane. The unpaired t-test showed that dichlorvos was significantly (p < 0.05) more toxic than lindane. The physical and chemical parameters data showed that over the 96h periods, the test pesticides caused slight increase in temperature, dissolved oxygen and ammonia of the test media, when compared with the untreated control. But they differentially altered pH, conductivity and alkalinity.
Conclusion. Since H. longifilis is sensitive to the test pesticides, it can therefore be considered as a good test species for the determination of acute toxicity and poisoning resulting from the pesticides and possibly for other compounds with similar intrinsic characteristics.

Local Anaesthetic Effect of Methanolic Leaves Extract of Lannea schimperi (Hoschst. Ex Rich) Eng by Hudu G. Mikail, David D. Akumka, Muhammed Adamu (279-286).
Background: Local anaesthetics provide relief from pain when applied locally to nerve tissue by blocking conduction of sensory nerve impulse from the receptor to the brain cortex.
Objective: This study aimed at evaluating local anaesthetic activity of the methanolic leaves extract of Lannea schimperi.
Methods: Six groups of five animals were used; groups I-IV were used for intracutaneous wheal test in guinea pigs for infiltration anaesthesia, while group V and VI were used for guinea pig corneal reflex method of surface anaesthesia.
Results: The result indicated a significant (P<0.05) dose dependent local anaesthetic activity of the methanolic leaves extract of Lannea schimperi with faster onset and longer duration of action at 24 mg/ml than at 12 mg/ml of the extract. Additions of 5 ?g of adrenaline into the 24 mg/ml preparation also prolonged the duration of local anaesthetic activity of the extract. The extract at 24 mg/ml significantly (P>0.05) inhibited corneal reflex, lidocaine was used as a standard drug in positive control group, while normal saline was used as negative control in all the treated groups.
Conclusion: The patent data therefore revealed that the methanolic leaves extract Lannea schimperi possess local anaesthetic principles that may require further scientific elucidation.

Background: Although many studies have been conducted on heavy metals in fish, there is no available information on the bioconcentration of lead in the African, air-breathing catfish, Heterobranchus longifilis (Valenciennes, 1840). Relevant patents relating to bioconcentration of lead in fish species were reviewed. Fish are useful in the evaluation of bioconcentration of lead and other metal pollutants in water.
Methods: The bioconcentration (uptake and depuration) of lead was determined by exposure of Heterobranchus longifilis (Valenciennes, 1840) fingerlings to untreated control and five sublethal concentrations of lead (0.0 - 0.3 mg l-1) in three replicates under laboratory conditions. After acclimation of the test species for 7 days, the experiments were undertaken in two phases for 28 days, comprising 14 days for uptake and 14 days for depuration. Samples of fish were taken out at three-day intervals for lead analysis. Lead concentrations were determined using Flame Atomic Absorption Spectrophotometer (UNICAM 969 model).
Results: Essential physical and chemical parameters of test media were determined, and the results were within the international standards. Generally, the concentration of lead increased from 0.0001 mg kg-1 (control) from 1st day of the experiment to 0.3305 mg kg-1 on the 14th day of uptake phase, and decreased to 0.3019 mg kg-1 on the 28th day of the depuration phase.
Conclusion: This study indicated that H. longifilis showed potential to accumulate and depurate lead.

Heavy Metal Concentrations in Some Edible Vegetables: A Case Study in Uyo and Ibesikpo Asutan Local Government Areas of Akwa-Ibom State by Ogbemudia F. Okpako, Iziegbe L. Igbinosun, Mbong E. Okon, Tochi G. Chilaka (295-303).
Background: This study assessed the level of heavy metals (Zn, Cu, Mn, Hg and Fe) accumulation in the leaves of five vegetables viz: Telfairia occidentalis, Heinsia crinata, Gnetum africanum, Talinum triangulare and Vernonia amygdalina planted in different gardens in Ibesikpo Asutan and Uyo L.G.As in Akwa Ibom State, Nigeria using standard scientific methods and reviewing latest patents.
Methods: Soil samples were obtained at a depth of 0 - 10 cm each at the base of each vegetable using soil auger.
Results: The results obtained from this study showed that the nutrient status and heavy metals concentrations of the soil of the two Local Government Areas were not significantly (P= 0.05) different. However, the levels of the heavy metals contents of the leaves of the vegetables were observed to fall within World Health Organisation (WHO) permissible concentration range. This observation indicated that there are little or no anthropogenic activities in or around the garden leading to the emission of heavy metals into the environment. Also, the result attributes the low heavy metals accumulation in the soil and poor translocation to the use of organic supplements in the gardens.
Conclusion: The finding of this study certifies that there is no risk associated with the consumption of vegetables from these farms. This result is discussed in line with current global trends in pollution management and dietetics.

Patent Selection (304-305).